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101.
Estradiol rapidly modulates hippocampal synaptic plasticity and synaptic transmission; however, the contribution of the various estrogen receptors to rapid changes in synaptic function is unclear. This study examined the effect of estrogen receptor selective agonists on hippocampal synaptic transmission in slices obtained from 3–5‐month‐old wild type (WT), estrogen receptor alpha (ERαKO), and beta (ERβKO) knockout female ovariectomized mice. Hippocampal slices were prepared 10–16 days following ovariectomy and extracellular excitatory postsynaptic field potentials were recorded from CA3‐CA1 synaptic contacts before and following application of 17β‐estradiol‐3‐benzoate (EB, 100 pM), the G‐protein estrogen receptor 1 (GPER1) agonist G1 (100 nM), the ERα selective agonist propyl pyrazole triol (PPT, 100 nM), or the ERβ selective agonist diarylpropionitrile (DPN, 1 µM). Across all groups, EB and G1 increased the synaptic response to a similar extent. Furthermore, prior G1 application occluded the EB‐mediated enhancement of the synaptic response and the GPER1 antagonist, G15 (100 nM), inhibited the enhancement of the synaptic response induced by EB application. We confirmed that the ERα and ERβ selective agonists (PPT and DPN) had effects on synaptic responses specific to animals that expressed the relevant receptor; however, PPT and DPN produced only a small increase in synaptic transmission relative to EB or the GPER1 agonist. We demonstrate that the increase in synaptic transmission is blocked by inhibition of extracellular signal‐regulated kinase (ERK) activity. Furthermore, EB was able to increase ERK activity regardless of genotype. These results suggest that ERK activation and enhancement of synaptic transmission by EB involves multiple estrogen receptor subtypes. © 2015 Wiley Periodicals, Inc.  相似文献   
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ObjectiveExploration of the feasibility of serum protein profiles for monitoring tumor radioresponse in cervical cancers using HPLC-LIF system.Materials and methodsTwenty-one subjects were recruited in the study. Out of them 7 were healthy, 14 were cervical cancer patients who undertook fractionated radiotherapy (RT) with 2 Gy per fraction over 25 fractions, for 5 weeks followed by 2 applications of intracavitary brachytherapy once a week.Blood collected from above subjects was processed to obtain serum. Serum chromatograms of ‘normal’ (n=7) and conspicuous probes before RT (n=14, ‘malignant’) and 24 h after second fraction of RT (n=13, ‘2-RT’), were recorded using an In-house-built HPLC-LIF set-up. Data were analyzed in two approaches: (1) classical method using relative intensities of selected peaks, (2) principal component analysis (PCA).Clinical assessment of tumor radioresponse was carried out 4 months after first fraction of RT and the degree of the tumor shrinkage was determined as an index of radioresponsiveness (complete response (CR): 100% shrinkage, partial response (PR): ≥50% shrinkage, and no response (NR): ≤50% shrinkage) which was further correlated with the analysis of 2-RT serum chromatograms.ResultsNormal vs. malignant chromatograms demonstrated pronounced differences in the 800–1800 s region. Malignant vs. 2-RT chromatograms showed minute variations in the 1300–1800 s region. Our analysis, in both of the approaches, produced clear differentiation between ‘normal’ and ‘malignant’, whereas differentiation between ‘malignant’ and ‘2-RT’ was minimal. Clinical evaluation of the tumor radioresponse yielded that out of 13 patients (one patient discontinued the radiotherapy) ten showed CR, two showed PR and one NR. In case of prediction of tumor radioresponse, analysis of the 2-RT chromatograms produced only minor differentiation among CR, PR and NR groups.ConclusionProtein profiling of serum samples differentiated ‘normal’ from ‘malignant’, but could not differentiate ‘malignant’ from ‘2-RT’. Also this technique has limited application in prediction of tumor radioresponse.  相似文献   
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This study utilized data from the national ACCESS program (N = 7224) to investigate the prevalence of suicidal ideation and suicide attempts in a sample of homeless people with mental illness. The prevalence of suicidal ideation in this sample was high (66.2% lifetime prevalence). In addition, 51.3% of the sample reported that they had ever attempted suicide, 26.9% reported an attempt that resulted in a nonpsychiatric hospitalization, and 8% reported an attempt in the previous 30 days. Youth, substance abuse, and psychiatric symptoms were all significantly associated with suicide attempts. Those who reported a recent attempt also reported higher rates of mental health care utilization, particularly inpatient care. The authors conclude that homeless people with mental illness are at particularly high risk for suicidal behavior, however, only in part because of the high prevalence of traditional risk factors.  相似文献   
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BACKGROUND: Shoe dermatitis is a form of contact dermatitis resulting from exposure to shoes. Different chemicals, in conjunction with a hot and humid environment within the shoe, give rise to allergic or irritant dermatitis. Allergic shoe dermatitis is commonly caused by constituents of rubber, leather, adhesives, and rarely by linings and dyes. AIM: To determine the frequency of various allergens in shoe dermatitis in our patients. METHODS: One hundred and nine patients suspected of having contact dermatitis due to shoe allergens were included. All patients were patch tested with the Shoe series and European Standard series. Patches were applied on the upper back and removed after 48 h. Results were read at 48, 72, and 120 h and interpreted according to International Contact Dermatitis Research Group (ICDRG) criteria. RESULTS: Of the 119 patients, 87 (73%) reacted positively to various allergens, 48% of whom showed polysensitivity. Glues (33.6%), particularly para-tert-butylphenol formaldehyde resin (PTBP-FR) (26.9%), were the leading cause of shoe dermatitis. Other allergens were leather chemicals (26.4%), potassium dichromate (16.18%), rubber allergens (7.6%), and dyes (7.6%). Shoe scrapings tested positive in 26.3% of patients. Other common allergens were nickel sulfate (22.7%), neomycin sulfate (10.1%), and cobalt chloride (8.4%). CONCLUSIONS: Considering the diversity of allergens, all patients presenting with shoe dermatitis should be patch tested with the Shoe series and a standard series to determine the etiologic allergens.  相似文献   
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Relapsed and late-onset Nipah encephalitis   总被引:3,自引:0,他引:3  
An outbreak of infection with the Nipah virus, a novel paramyxovirus, occurred among pig farmers between September 1998 and June 1999 in Malaysia, involving 265 patients with 105 fatalities. This is a follow-up study 24 months after the outbreak. Twelve survivors (7.5%) of acute encephalitis had recurrent neurological disease (relapsed encephalitis). Of those who initially had acute nonencephalitic or asymptomatic infection, 10 patients (3.4%) had late-onset encephalitis. The mean interval between the first neurological episode and the time of initial infection was 8.4 months. Three patients had a second neurological episode. The onset of the relapsed or late-onset encephalitis was usually acute. Common clinical features were fever, headache, seizures, and focal neurological signs. Four of the 22 relapsed and late-onset encephalitis patients (18%) died. Magnetic resonance imaging typically showed patchy areas of confluent cortical lesions. Serial single-photon emission computed tomography showed the evolution of focal hyperperfusion to hypoperfusion in the corresponding areas. Necropsy of 2 patients showed changes of focal encephalitis with positive immunolocalization for Nipah virus antigens but no evidence of perivenous demyelination. We concluded that a unique relapsing and remitting encephalitis or late-onset encephalitis may result as a complication of persistent Nipah virus infection in the central nervous system.  相似文献   
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