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21.
Cortical spreading depression (CSD) is a brain electrical response related to neural activity and probably also related to diseases like migraine and epilepsy. Adverse conditions like malnutrition and exposure to a warm environment early-in-life can permanently alter brain development, changing electrophysiological features of the brain responses and rendering the brain prone to febrile seizures. Here we investigated the lasting effects of heat exposure on brain CSD propagation in well-nourished and malnourished developing rats. From postnatal days 10–29, rats were exposed to daily sessions (one session per day, five sessions per week during 3 weeks; total of 15 sessions) of a warm environment (40 ± 2 °C). At 30–40 days and 90–120 days of life (young and adult age-ranges, respectively), they were anesthetized (urethane + chloralose; 1000 + 40 mg/kg ip) and the electrocorticogram plus the slow potential change accompanying CSD were recorded on two parietal points for 4 h. Compared to controls (maintained on the normal environment temperature, 23 ± 2 °C), heat-exposed rats displayed higher CSD velocities of propagation (P < 0.05; ANOVA plus Tukey test) at both age-ranges and nutritional statuses. The mean ± S.D. CSD velocities (in mm/min) were: for control- and heat-exposed well-nourished rats, 3.75 ± 0.15 and 4.17 ± 0.19 (young groups), and 3.33 ± 0.06 and 3.88 ± 0.26 (adult); for the same control and heat exposure conditions in the malnourished rats, 4.30 ± 0.22 and 5.31 ± 0.46 (young), and 4.18 ± 0.20 and 4.88 ± 0.35 (adult). In contrast to early malnutrition, heat exposure did not affect body and brain weights. Data support the hypotheses that (1) early heat exposure long-lasting facilitates CSD propagation and (2) this effect is not modified by early malnutrition.  相似文献   
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To investigate race differences in retrospectively-reported early smoking experiences, we studied African-American (n = 48) and Caucasian (n = 155) current smokers who participated in a study designed to identify phenotypic and genotypic factors associated with smoking. Compared with Caucasian smokers, African-American smokers were less educated (mean ± s.e.m.: 13.3 ± 0.25 vs. 14.3 ± 0.16; p < .01), had higher BMI (28.9 ± 1.06 vs. 26.7 ± 0.52; p < .05), and smoked significantly fewer cigarettes/day (14.1 ± 1.00 vs. 18.4 ± 0.74; p < .01). Ninety percent of African-American smokers consumed menthol cigarettes, as opposed to 25% of Caucasian smokers. African-American smokers were significantly older than Caucasian smokers upon initial smoking experimentation (17.4 ± 1.1 vs. 14.7 ± 0.3; p < .05) and onset of regular smoking (19.7 ± 0.9 vs. 17.4 ± 0.4; p < .05). African-American smokers were significantly more likely than Caucasian smokers to endorse global pleasurable sensations (48% vs. 30%; p < .05), “pleasurable rush or buzz” (62% vs. 43%; p < .05), and “relaxing” (45% vs. 27%; p < .05) as early experiences with smoking, whereas Caucasian smokers were marginally more likely to report dizziness and difficulty inhaling (61% vs. 45%; p < .10 and 48% vs. 31%; p < .10, respectively). Caucasian smokers were significantly more likely to endorse friends (6.9 ± 0.2 vs. 4.8 ± 0.4; p < .0001) and “perk me up” (4.2 ± 0.3 vs. 3.1 ± 0.4; p < .05) and marginally more likely to endorse buzz (4.2 ± 0.2 vs. 3.4 ± 0.5; p < .10) as reasons for starting to smoke. Further research is needed to determine the relative contributions of genetic, developmental, and socio-cultural factors to these findings.  相似文献   
23.
Photodynamic diagnosis in urology: state-of-the-art   总被引:2,自引:0,他引:2  
OBJECTIVES: To provide an overview on the methodology and clinical relevance of fluorescence diagnosis with exogenous fluorochromes or fluorochrome prodrugs in urology. METHODS: The methodology is summarised on the basis of our experience and the relevant literature. Clinical results and perspectives are reported and concluded after we scanned and evaluated sources from PubMed. Search items were "aminolev*" or "hypericin" or "photodyn*" or "porphyrin" or "fluorescence" or "autofluorescence" and "bladder" or "prostate" or "kidney" or "peni*" or "condylo*". Some literature was also obtained from journals not indexed. RESULTS: A large number of clinical trials have shown that photodynamic diagnosis (PDD) improves the ability to detect inconspicuous urothelial carcinoma of the bladder. Fluorescence diagnosis has recently been approved in Europe for the detection of bladder cancer after instillation of a hexaminolevulinate (Hexvix) solution. PDD is recommended by the European Association of Urology for the diagnosis of carcinoma in situ of the bladder. To date, the major weakness of PDD for the detection of bladder cancer is its relatively low specificity. Initial results with PDD for the detection of penile carcinoma, prostate cancer, kidney tumours, and urethral condylomata are promising. CONCLUSIONS: To determine the actual impact of PDD on recurrence and progression rates of bladder cancer, further long-term observational studies are necessary. These studies also will clarify whether PDD is cost efficient.  相似文献   
24.
An illusory sensation of ownership over a surrogate limb or whole body can be induced through specific forms of multisensory stimulation, such as synchronous visuotactile tapping on the hidden real and visible rubber hand in the rubber hand illusion. Such methods have been used to induce ownership over a manikin and a virtual body that substitute the real body, as seen from first-person perspective, through a head-mounted display. However, the perceptual and behavioral consequences of such transformed body ownership have hardly been explored. In Exp. 1, immersive virtual reality was used to embody 30 adults as a 4-y-old child (condition C), and as an adult body scaled to the same height as the child (condition A), experienced from the first-person perspective, and with virtual and real body movements synchronized. The result was a strong body-ownership illusion equally for C and A. Moreover there was an overestimation of the sizes of objects compared with a nonembodied baseline, which was significantly greater for C compared with A. An implicit association test showed that C resulted in significantly faster reaction times for the classification of self with child-like compared with adult-like attributes. Exp. 2 with an additional 16 participants extinguished the ownership illusion by using visuomotor asynchrony, with all else equal. The size-estimation and implicit association test differences between C and A were also extinguished. We conclude that there are perceptual and probably behavioral correlates of body-ownership illusions that occur as a function of the type of body in which embodiment occurs.  相似文献   
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The way in which individuals attend to pain-related stimuli is thought to affect their pain experience. Early and late stages of processing, with shifts from attentional engagement to disengagement (avoidance), have been identified, but rarely investigated in the same protocol. Therefore, the present study aimed to consider 2 time frames that might be indicative of attentional engagement and disengagement. One hundred pain-free individuals performed a modified dot-probe task with pictorial stimuli displaying affective facial expressions (ie, pain, anger, joy, neutral face), presented either for 100 ms or for 500 ms. Because fear of pain has been found to moderate attentional processing of pain stimuli, the Fear of Pain Questionnaire (FPQ III) was also administered. Results indicated both early attentional engagement and later disengagement (avoidance) for negative facial expressions (anger, pain). This pattern was most prominent for pain faces and among those participants high in pain-related fear. Taken together, these findings provide evidence that the dot-probe task is suitable to investigate different stages of attentional processing for pain-related stimuli. In accordance with the vigilance-avoidance hypothesis, pain-related stimuli seem to attract attention quickly, but attentional avoidance may occur shortly after.PerspectiveWe focused on different stages of attentional processing of pain faces in pain-free individuals. Results highlight the importance of distinguishing between early (engagement) and later (disengagement) components of attention, as well as considering the role that fear of pain has in understanding the nature of these effects.  相似文献   
28.
TNF downmodulates the function of human CD4+CD25hi T-regulatory cells   总被引:15,自引:0,他引:15       下载免费PDF全文
CD4+CD25+ T-regulatory cells (Tregs) play an essential role in maintaining immunologic homeostasis and preventing autoimmunity. However, little is known about the exogenous factors that regulate their differentiation and function. Here, we report that TNF inhibits the suppressive function of both naturally occurring CD4+CD25+ Tregs and TGFbeta1-induced CD4+CD25+ T-regulatory cells. The mechanism of this inhibition involves signaling through TNFRII that is constitutively expressed selectively on unstimulated Tregs and that is up-regulated by TNF. TNF-mediated inhibition of suppressive function is related to a decrease in FoxP3 mRNA and protein expression by the Tregs. Notably, CD4+CD25hi Tregs isolated from patients with active rheumatoid arthritis (RA) expressed reduced levels of FoxP3 mRNA and protein and poorly suppressed the proliferation and cytokine secretion of CD4+ effector T cells in vitro. Treatment with anti-TNF antibody (infliximab) increased FOXP3 mRNA and protein expression by CD4+CD25hi Tregs and restored their suppressive function. Thus, TNF has a novel action in modulating autoimmunity, by inhibiting CD4+CD25+ Treg activity.  相似文献   
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OBJECTIVES:

The current study sought to identify macroscopic placental changes associated with clinical conditions in women with or without diabetes and their newborns.

METHODS:

The study population consisted of 62 pregnant women clinically diagnosed with diabetes and 62 healthy women (control group).

RESULTS:

Among the subjects with diabetes, 43 women (69.3%) were diagnosed with gestational diabetes mellitus, 15 had diabetes mellitus I (24.2%), and four had diabetes mellitus II (6.5%). The mean age of the women studied was 28.5±5.71 years, and the mean gestational age of the diabetic women was 38.51 weeks. Of the 62 placentas from diabetic pregnancies, 49 (79%) maternal surfaces and 59 (95.2%) fetal surfaces showed abnormalities, including calcium and fibrin deposits, placental infarction, hematoma, and fibrosis. A statistical association was found between newborn gender and fetal and maternal placental changes (p = 0.002). The mean weight of the newborns studied was 3,287±563 g for women with diabetes mellitus, 3,205±544 g for those with gestational diabetes mellitus, 3,563±696 g for those with diabetes mellitus II, and 3,095±451 g for those with diabetes mellitus I.

CONCLUSIONS:

Infarction, hematoma, calcification, and fibrin were found on the maternal and fetal placental surfaces in women with diabetes. Women with gestational diabetes and post-term infants had more calcium deposits on the maternal placental surface as compared to those with type I and type II diabetes.  相似文献   
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