Standardized extracts of flavonoids increase the viability of PC12 cells treated with hydrogen peroxide: effects on oxidative injury

Oxidative stress plays an important role in cell death associated with many diseases. In the present study, concentration-dependence of hydrogen peroxide on rat pheochromocytoma (PC12) cell viability was studied. Preventive effects of antioxidants on the viability of these cells treated with 2 mM hydrogen peroxide were compared. Trolox and Stobadine, as chain-breaking antioxidants were studied in comparison with standardized extracts of flavonoids of Ginkgo biloba and Pycnogenol, known as agents effective in several diseases. All antioxidants increased the viability of hydrogen peroxide-treated PC12 cells. Flavonoid extracts were more effective than Trolox and Stobadine. Antioxidants were most effective if present after the oxidative treatment. As expected, the preloading with antioxidants was without effect on cell viability. Correlations between viability increase induced by antioxidants, and content of oxidation products of proteins and lipids were studied at concentrations of antioxidants mostly effective in preventing cell death: Trolox (10 microM), Stobadine (30 microM), Ginkgo biloba (160 microg/ml), Pycnogenol (100 microg/ml). In these concentrations, antioxidants did not statistically significantly decrease the content of protein carbonyls, with exception of Stobadine, which had no effect. Ginkgo biloba, Trolox and Stobadine intensively decreased the content of malondialdehyde, a product of lipid peroxidation. Pycnogenol was without any preventive effect. Concentrations of antioxidants with a large effect on viability of PC12 cells were not effective in preventing oxygen radical-induced injury of proteins. Antioxidants prevented the oxidative injury of lipids more effectively than that of proteins.     

Regulation of CC chemokine receptor 5 in hepatitis G virus infection

INTRODUCTION: Epidemiological data demonstrate an association between hepatitis G virus (HGV) co-infection and improved survival of HIV-positive individuals. However, the mechanism by which HGV affects progression of HIV disease remains unclear. As down-regulation of CC chemokine receptor 5 (CCR5) delays HIV progression, we investigated whether CCR5 expression is altered by exposure of lymphocytes to HGV proteins. METHODS: A cross-sectional analysis of CCR5 expression was carried out on CD4 and CD8 T lymphocytes of 11 HGV-positive and 12 HGV-negative persons, who were homozygous for the CCR5 wild-type gene. Binding of the HGV E2 protein to CD81 was analysed by flow cytometry. Lymphocytes were stimulated with immobilized HGV E2, anti-CD81 or serum proteins from HGV-infected subjects and changes in CCR5 expression and CC chemokine secretion were determined. RESULTS: We demonstrate that the HGV envelope protein E2 specifically binds to CD81 on T lymphocytes. This interaction induces a dose-dependent release of RANTES and down-regulation of CCR5 surface expression with concomitant intra-cellular accumulation of CCR5 proteins. This effect of HGV E2 on CCR5 expression was confirmed when lymphocytes were incubated with serum proteins from HGV-infected subjects. Finally, our cross-sectional analysis revealed CCR5 expression to be reduced by 53% and 36% on CD4 and CD8 lymphocytes of HGV-infected subjects, respectively (P < 0.01). CONCLUSIONS: Our results demonstrate that an interaction of HGV E2 with CD81 leads to increased RANTES secretion and decreased CCR5 surface expression. This mechanism might contribute to the delayed progression of HIV-infection in HGV-coinfected patients.     

Postoperative colonic motility in patients following laparoscopic-assisted and open sigmoid colectomy

Clinical reports on laparoscopic-assisted sigmoid colectomy (LASC) suggest that the period of postoperative inhibition of gastrointestinal motility is shortened as compared to open sigmoid colectomy (OSC). We aimed to specifically investigate whether colonic motility increases more rapidly following LASC compared to OSC. LASC was performed in 11 patients and OSC in nine patients for recurrent diverticulitis or carcinoma. During surgery a manometry catheter was inserted into the colon via the anus, and the tip was placed in the splenic flexure. Continuous manometric recordings were performed from the day of surgery until postoperative day 3 with a four-channel microtransducer manometry system combined with a portable data logger. The postoperative colonic motility index was 101± 18, 199 ± 30, and 163 ±27 mm Hg/min on days 1,2, and 3 after LASC, respectively, which was increased compared to indexes of 53 ± 15, 71 ± 18, and 76 ± 23 following OSC (mean ± standard error of the mean; P < 0.05). The amplitude but not the frequency of contractions was higher following LASC compared to OSC. Following LASC, patients requested a similar amount of pain medication but resumed oral food more rapidly on postoperative days 2 and 3 (P < 0.05), and they were discharged from the hospital earlier (P < 0.05). Colonic motility in particular and the patient’s condition in general seem to improve more rapidly following LASC compared to the open procedure. Presented at the Forty-Fourth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Florida, May 17–22, 2003 (oral presentation).     

Decisions about sectioning and medicating of schizophrenic patients in Germany and England--results of a comparative study

Questionnaires with three case summaries have been presented to 143 psychiatrists in Germany and 27 in England. All three case summaries regard patients with schizophrenia who either show risk to themselves or others. The psychiatrists were asked whether they would recommend sectioning and furthermore whether they would recommend treatment against the patient's will. In the case regarding a risk to others there was widespread approval of sectioning and treatment (Germany 85 %, England 93 %) against the patient's will. Significant differences were seen in the cases of risk to the patients themselves with regards to treatment against the patient's will. This was the case with a scenario involving a young man with his first presentation of schizophrenia as well as in the case of a middle aged man presenting with chronic psychotic symptoms and self-neglect (approval in England: 96 % and 93 % respectively, in Germany: 63 % and 59 % respectively, p < 0.001 for both). When a logistic regression was performed the country of work was the most important predictive factor in deciding whether or not to treat a patient against his will.     

Impairment of protein homeostasis and decline of proteasome activity in microglial cells from adult Wistar rats

Common symptoms of different neurodegenerative diseases start to develop in the second half of the human life. Several of these diseases, including Alzheimer's and Parkinson's disease, are accompanied by severe disturbances of protein metabolism and homeostasis in the brain. Because microglial cells are, to some extent, responsible for the maintenance of this homeostasis, age-related functional changes of the microglia are important. We established, therefore, the preparation of cultures of primary microglial cells isolated from adult animals in comparison to the widely used standard model, primary microglial cells isolated from newborn animals. In addition, we investigated changes in the activation and in the protein homeostasis within these cells. The protein turnover seems to be significantly impaired in microglial cells isolated from adult animals and this seems to be accompanied by a decline in proteasomal function, but not in the protease content. We were also able to demonstrate higher cell surface molecule expression and a higher basal NO release of microglia isolated from adult animals in comparison to the microglia isolated from newborn rats; however, the PMA stimulated oxidative burst was abolished completely in cells from adult animals. Microglia from adult animals were also not able to upregulate their protein metabolism after activation. From these investigations it was concluded that microglial cells from adult animals have significantly different metabolic properties in comparison to the widely used microglial cells from newborn animals.     

Lack of creatine in muscle and brain in an adult with GAMT deficiency

Guanidinoacetate methyltransferase deficiency, which so far has been exclusively detected in children, was diagnosed in a 26-year-old man. The full-blown spectrum of clinical symptoms already had been present since infancy without progression of symptoms during adolescence. Cranial magnetic resonance imaging showed normal findings. Ophthalmological examination showed no retinal changes. Besides creatine deficiency in the brain, a distinct lack of phosphocreatine in skeletal muscle was proved by (31)P magnetic resonance spectroscopy. Creatine substitution combined with a guanidinoacetate-lowering diet introduced first at the age of 26 years was shown to be effective by an impressive improvement of epileptic seizures, mental capabilities, and general behavior and by normalization of the (31)P spectrum in the skeletal muscle.     

Allogeneic dendritic cells fused with tumor cells: preclinical results and outcome of a clinical phase I/II trial in patients with metastatic renal cell carcinoma

Therapeutic vaccination with dendritic cells (DC) can lead to tumor regression in animal models and has shown promising results in the first clinical trials of metastatic renal cell carcinoma and malignant melanoma. In vitro data and results of a clinical phase I/II trial using DC tumor fusions in patients with progressive metastatic renal cell carcinoma are presented here. In addition to toxicity and feasibility, complex immune monitoring was a point of interest. DC precursor cells were obtained from the peripheral blood mononuclear cells (PBMCs) of healthy donors and were fused with either allogeneic (8 patients) or autologous (4 patients) renal tumor cells. In total, 12 patients with progressive metastatic renal cell carcinoma were treated with an average of 2.8 x 10(7) tumor cells fused with 1.8 x 10(7) DC each administered on days 0, 28, and 56 intradermally. Fusion efficacy for the tumor cells used was 14.3% +/- 7.8%. Cell viability was 59.8% +/- 6.8% after fusion and irradiation. We observed no adverse effects and no difference in clinical outcome between the allogeneic and the autologous treatment. Eight patients remained in a progressive disease state and four patients in a stable disease state. T-cell immunity was carefully monitored before, during, and after treatment. Delayed-type hypersensitivity (DTH) reaction using tumor cells was positive after treatment in 7 of 12 patients, 2 of whom were found to have stable disease. An increase in the reactivity against recall antigens was seen in most patients. Interestingly, cytotoxicity of peripheral blood lymphocytes (PBLs) against renal cell carcinoma cells increased during treatment as well as the percentage of interferon-gamma-secreting cells. This effect was significantly enhanced within the group that had stable disease. The lack of adverse effects together with positive immunologic signs justifies further investigation of this novel therapeutic approach. Further studies are necessary to test for clinical effectiveness in patients with tumors, especially those with less advanced disease.     

Acute effects of alcohol on divided and covert attention in men

RATIONALE: While several studies identified divided attention to be sensitive to alcohol effects, the impact of alcohol on covert visual attention is still not clear, despite the latter's important role in perception. OBJECTIVES: The study tests the effect of acute moderate doses of alcohol on divided and covert attention in right-handed, male volunteers. METHODS: The design of the study involved a double-blind trial with an alcohol and a placebo condition; measurements were taken before and after an oral dose of 0.6 g/kg alcohol versus placebo. In the divided-attention task, simultaneous visuo-spatial and auditory stimulation was applied. In a test of covert attention, subjects had to shift their attentional focus according to a central cue, from one location in the visual field to another. RESULTS: Under the divided-attention condition, reaction times were significantly prolonged after alcohol ingestion compared to placebo. Covert attention pre-post change was also significantly different between the alcohol and placebo groups. There is a reduction of false-cueing disturbance for left-appearing stimuli under moderate alcohol but an increase of disturbance for rightward stimuli, i.e. we found a lateralised pattern of reaction for spatial orienting. In the placebo group, no significant differences in right-left performance were obtained. CONCLUSION: The results suggest that sensory-attentional mechanisms play a key role in altered visual perceptual performance after alcohol ingestion. Furthermore, differences between the right and left visual field in the cued target-detection task indicate that alcohol exerts an influence on right-hemispheric attentional priming.     

Simultaneous in vivo measurements of intranasal air and mucosal temperature

Nasal cavity volume and blood temperature along the nasal airways, reflecting the mucosal temperature, are considered to be the most important predictors of nasal air conditioning. The purpose of this study was to simultaneously in vivo measure intranasal air as well as mucosal temperature for the first time. Fifteen healthy subjects were enrolled into the study. Two combined miniaturized thermocouples were used for simultaneous recording of intranasal air and mucosal temperature within the anterior turbinate area close to the head of the middle turbinate without interruption of nasal breathing. The highest air and mucosal temperature values were detected at the end of expiration, the lowest values at the end of inspiration. The difference was statistically significant (P < 0.05). The mean mucosal temperature ranged from 30.2 ± 0.9 to 32.2 ± 0.8°C. The mean air temperature ranged from 28.5 ± 1.2 to 34.1 ± 0.7°C. The mean differences between air and mucosal temperature were 1.7 ± 0.5°C after inspiration and 1.9 ± 0.7°C after expiration. Simultaneous measurements of intranasal air and mucosal temperature are practicable. The detected temperature gradient between air and mucosa confirm a relevant heat exchange during inspiration and expiration. This gradient between air and mucosa is obligatory for heat and water exchange to ensure adequate nasal air conditioning.     

A longitudinal study of emotional experience,expressivity, and psychopathology in psychotherapy inpatients and psychologically healthy persons

The authors investigated changes of emotional experience and expressivity in 34 inpatients undergoing psychodynamic therapy and in 29 healthy persons who were assessed at parallel time intervals. Participants completed 2 measures of psychopathology (Symptom Checklist‐90 Revised and Inventory of Interpersonal Problems‐64) and took part in relationship episode interviews. The emotional experiences they reported and their nonverbal emotional expressivity during the interviews were assessed by independent raters. Regardless of when they were assessed, the patients reported a greater number of emotions and a greater variety of emotions. Psychopathology in the patient group decreased in the course of treatment, but there were no systematic changes in the emotional domain. The findings challenge the common notion of psychopathology being associated with impaired awareness and expression of emotions. © 2010 Wiley Periodicals, Inc. J Clin Psychol 66:1–17, 2010.