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1.
N‐acyl‐dopamines are a novel class of biologically active lipids that have recently been identified in the brain and have the potential to interact with neural signaling pathways. This study seeks to determine the ability of N‐oleoyl‐dopamine, a synthetic amide of oleic acid and dopamine, to cross the blood brain barrier. We determined the tissue content of radioactivity in selected brain regions, in a short‐run study design, following injections of [3H]N‐oleoyl‐dopamine (0.4 µCi) into the internal carotid artery in the rat. These results were compared with intracarotid injections of [3H]dopamine and with intravenous injections of both radiolabeled compounds. The level of radioactivity was determined using liquid scintillation and was expressed as the percentage of its total dose injected per gram of tissue. We found that the 15‐min brain uptake of radioactivity, with no distinct regional variations, amounted to about 6% following the intracarotid [3H]N‐oleoyl‐dopamine, which was a significant 3–4‐fold increase over that following similar administration of [3H]dopamine. Intravenous injections of [3H]N‐oleoyl‐dopamine gave a much smaller yield of radioactivity in brain tissue samples which was still severalfold greater than that for intravenous [3H]dopamine. Qualitative thin‐layered chromatography screening showed the presence of unchanged N‐oleoyl‐dopamine in the brain following injections. We conclude that N‐oleoyl‐dopamine has an appreciable ability to cross the blood‐brain barrier, which contrasts the limited transfer of dopamine alone. N‐oleoyl‐dopamine might exert physiological effects due to its known affinity for the central vanilloid receptors or to better satisfying the brain tissue demand for dopamine. The study suggests a potential pharmacological role for N‐oleoyl‐dopamine delivered exogenously in helping regulate the brain function. Drug Dev. Res. 60:217–224, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
2.
Plasma alpha beta levels have been examined in sporadic Alzheimer's disease yielding conflicting results; both no difference and an increase in plasma concentrations of alpha beta42 and alpha beta40 in sporadic cases of AD as compared to controls have been reported. Elevated plasma alpha beta42 levels may be detected several years before the onset of symptoms (in mild cognitive impairment stadium). Levels of alpha beta40 and alpha beta42 were measured in plasma from 54 patients with AD, 39 subjects with MCI and 35 controls using a commercially available ELISA. Mean plasma alpha beta42 levels were significantly higher in MCI as compared to both AD (P < 0.001) and control subjects (P < 0.001), while alpha beta40 did not differ between the groups. No correlations were observed between alpha beta levels and age, MMSE scores or gender. According to ROC curve analysis the maximum accuracy in discriminating MCI versus both controls and AD subjects has been achieved using a cut-off value of 3.8.  相似文献   
3.
Lipooligosaccharides (LOS) isolated from Bordetella pertussis strains 186 and 606 were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-resolution magic angle spinning nuclear magnetic resonance (NMR). These analyses distinguished between the LOS of strains 186 and 606, suggesting that the structure of LOS in B. pertussis is heterogeneous. The pentasaccharide was selectively cleaved from LOS of B. pertussis strain 186, purified, and covalently linked to a monomer fraction of tetanus toxoid. Injection of rabbits with the neoglycoconjugate emulsified in complete Freund's adjuvant yielded immunoglobulin G antibodies that were reactive with the LOS. These antibodies reacted strongly with B. pertussis LOS possessing the complete dodecasaccharide, as determined by an enzyme-linked immunosorbent assay, immunoblotting, and flow cytometry with intact, live bacterial cells. The binding epitope within the pentasaccharide was investigated by saturation transfer difference (STD) NMR spectroscopy. Protons H-1 and H-4 of the terminal alpha-D-GlcpNAc and proton H-6 and protons of an N-methyl group at H-4 of 3-substituted beta-L-FucpNAc4NMe exhibited the largest saturation transfers. STD NMR experiments confirmed that the immunodominant epitope recognized by the antineoglycoconjugate antibodies is located predominantly in the distal trisaccharide of B. pertussis 186 LOS. The antipentasaccharide antibodies induced by the conjugate inhibited the secretion of tumor necrosis factor alpha, interleukin-6, and NO by LOS-stimulated J774A.1 cells.  相似文献   
4.
INTRODUCTION: Recent years have seen a rise in the importance of cytokine production and co-stimulatory/activatory molecule expression in the immune response in leukemia. The aim of our study was to assess the function of T lymphocytes in children with acute lymphoblastic leukemia (ALL) during remission induction based on selected cytokine and co-stimulatory/activatory molecule expression. MATERIAL/METHODS: The study group consisted of 50 children with ALL (B cell precursor). Peripheral blood samples were taken before treatment (day 0), after the prednisone prophase (day 8), and during (day 15) and after (day 33) remission induction. The percentages of T cells with interferon (IFN)-gamma (Th(1)), interleukin (IL)-4 (Th(2)) and IL-2 receptor (IL-2R), CD28, CTLA-4, CD38, ICAM-1, and HLA-DR expression were assessed by tricolor flow cytometry. RESULTS: At the time of diagnosis we noted higher percentages of T cells with adhesion molecule ICAM-1, activation molecule CD38 expression, and an increased population of Th(2 )cells (IL-4) compared with the control group. During and after remission induction we observed a decreased population of CD38(+) T cells, elevated percentages of helper T lymphocytes with IL-2R expression, and a rise in helper T lymphocytes producing IFN-gamma (Th(1)). During fever/infection, higher levels of activated T lymphocytes (CD4(+)HLA-DR(+), CD8(+)HLA-DR(+)), a rise in Th1, and no change in Th(2 )populations were observed. CONCLUSIONS: The results suggest T cell activation and Th(2 )predominance at the time of diagnosis and during remission induction in ALL in children. These results confirm the involvement of cellular immunity in the leukemic process and can be used in immune therapy in leukemia.  相似文献   
5.
The incidence of asthma and other allergic diseases continues to increase. In addition to genetic factors, environmental influences are thought to play an important role. The aim of this study was to identify factors that influence and drive the atopic march from atopic sensitization to asthma in children from Lód?. METHODS: 800 atopic children, aged 5-18 years, were included to our study. Parents filled in questionnaires and gave interviews about their children's diseases. 405 (43%) children have diagnosis of asthma. RESULTS: A significant association was observed between asthma and male sex, parents' history of atopy, parental highest school grade, maternal smoking during pregnancy, maternal chronic disease (especially chronic renal diseases), maternal allergen-sensitizing diet during breast-feeding, increased exposure to indoor humidity and moulds. Similar effect was seen for episodes of wheeze occurring in the first 3 years of life as followed: wheezing during an airway infection, wheezing not connected with respiratory tract infection, wheezing not related with physical exercise. Child's daycare attendance (nursery school) was associated with decreased risk of asthma.  相似文献   
6.
The aim of the present study was to investigate the effect of small unilateral lesions to the ventromedial portion of the prefrontal cortex on two memory functions: memory for objects and memory for object locations. Patients, who had undergone surgery of the anterior communicating artery aneurysm, and normal control subjects, participated in the study. The patients were subdivided into two groups: with and without unilateral resection of the gyrus rectus. Subjects were presented with two memory tests, that required remembering either simultaneously presented visual stimuli (object memory test; OMT) or locations of the stimuli (location memory test; LMT). In the OMT, patients with resection of the gyrus rectus were impaired in comparison to patients without resection and normal control subjects. In the LMT, the three groups did not differ from each other. Our results suggest that the ventromedial prefrontal cortex is specifically involved in memory for objects.  相似文献   
7.
Many data suggest involvement of inflammation in neurodegeneration. However, the exact mechanisms of this cooperation are poorly understood. We have previously shown that induction of inflammatory reaction, both before and after injury of the striatum, affects regeneration of dopaminergic neurons. In the present research we studied the role of inflammatory reaction in non-injured striatum. We used myelin oligodendrocyte glycoprotein (MOG) 35-55 in complete Freund's adjuvant (CFA) to elicit experimental autoimmune encephalomyelitis (EAE) mice model. As determined by HPLC, striatal dopamine (DA) and serotonin levels in mice treated with either MOG 35-55 in CFA or CFA alone were significantly higher compared to vehicle-treated controls on 13th day after induction. The ratio of homovanilic acid/dopamine (HVA/DA) and 3, 4 dihydroxyphenylacetic acid/dopamine (DOPAC/DA) were significantly lower in the MOG and CFA groups on 13th day, indicating decreased DA metabolism. Noradrenaline (NA) concentration did not differ between groups. Moreover, the striatal mRNA IL-1beta and TNF-alpha levels were elevated during induction phase of EAE in both groups, as determined by RT-PCR. Our data indicate regulatory connection between dopaminergic and immune systems.  相似文献   
8.
Patients suffering from Crohn’s disease and ulcerative colitis are at higher risk of osteoporosis due to lower bone mineral density. Risk factors of osteoporosis are divided into unmodifiable, namely, age, gender, genetic factors, as well as modifiable, including diet, level of physical activity, and the use of stimulants. Coffee and tea contain numerous compounds affecting bone metabolism. Certain substances such as antioxidants may protect bones; other substances may increase bone resorption. Nevertheless, the influence of coffee and tea on the development and course of inflammatory bowel diseases is contradictory.  相似文献   
9.
Sarcopenia is a disorder characterized by a loss of muscle mass which leads to the reduction of muscle strength and a decrease in the quality and quantity of muscle. It was previously thought that sarcopenia was specific to ageing. However, sarcopenia may affect patients suffering from chronic diseases throughout their entire lives. A decreased mass of muscle and bone is common among patients with inflammatory bowel disease (IBD). Since sarcopenia and osteoporosis are closely linked, they should be diagnosed as mutual consequences of IBD. Additionally, multidirectional treatment of sarcopenia and osteoporosis including nutrition, physical activity, and pharmacotherapy should include both disorders, referred to as osteosarcopenia.  相似文献   
10.
Polycystic ovary syndrome (PCOS) is an increasingly common problem for women in the reproductive age throughout the entire world. A reduction diet with a low glycaemic index (GI) has proved to support the treatment of PCOS. The aim of the study was to analyse the influence of the diet on the level of vitamins soluble in water. The study included 55 women, 40 of which suffered from PCOS (identified by means of the Rotterdam Criteria) and 15 healthy women of the Caucasian race. The level of vitamins before and after the dietary intervention was measured. The diet was a reduction diet with a reduced glycaemic index (GI). Biochemical analyses were made on the basis of liquid chromatography—Infinity 1260 Binary liquid chromatography (LC) Agilent Technology. The level of vitamins in the serum was analysed together with the consumption before and after the dietary intervention. A higher level of vitamin C in the plasma was observed before and after the dietary intervention in the PCOS group in comparison to the control group despite the lower intake of this vitamin in the PCOS group. The remaining vitamins were at a comparable or lower level (B1, B3, B5, B6 and B12). After the dietary intervention, only B1 and B9 were at a clearly lower level (a trend of p = 0.093 and p = 0.085). A properly balanced reduction diet with reduced GI improves the supply of vitamins in women with PCOS. An additional recommendation should be the additional supplementation of B1, niacinamide and the combination of folates with inositol. The level of vitamin C in the plasma may not be a good marker of its supply in the PCOS group.  相似文献   
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