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11.
Wastewater-based epidemiology (WBE) is a promising biomonitoring approach with the potential to provide direct information on human intake and exposure to food contaminants and environmental chemicals. The aim of this study was to apply WBE while employing the normalization method for exploring human exposure to selected mycotoxins according to population biomarker 5-hydroxyindoleacetic acid (5-HIAA). This type of normalization technique has been previously used to detect various other compounds. However, to the best of our knowledge, this is the first study tracking human exposure to mycotoxins. A sensitive analytical methodology was developed to achieve reliable quantification of deoxynivalenol, enniatins, and beauvericin in wastewater (WW) samples. The applicability of the method was evaluated by testing 29 WW samples collected at WW treatment plants in Latvia. With frequency of detection greater than 86%, enniatins B, B1, A, and A1 were revealed in WW samples. The estimated total daily intake for enniatins was in the range of 1.8–27.6 µg/day per person. Free deoxynivalenol (DON) was determined in all analysed WW samples. Based on the average 5-HIAA excretion level and the determined 5-HIAA content in the samples, the intake of DON by the human population of Riga was estimated at 325 ng/kg b.w. day.  相似文献   
12.
Alkali-activated systems (AAS) represent an ecologically and economically sustainable inorganic binder as an alternative to ordinary Portland cement (OPC). One of the main benefits of AAS is their durability in aggressive environments, which can be equal or even better than that of OPC. In this paper, the influence of the type of alkaline activator in alkali-activated blast furnace slag (AAS) in terms of resistance to sulfur dioxide corrosion was investigated. The durability testing process was based on the CSN EN ISO 3231 standard and simultaneously compared with mortar samples prepared by using Blastfurnace cement CEM III/A 32.5R. The degradation progress was evaluated by employing several different methods such as observing the compressive strength development, weight change evaluation, non-destructive testing methods like ultrasound or impact echo technique, or visual phenolphthalein technique. Subsequently, fundamental characterization of samples by the XRD method was performed during the degradation test. The obtained results indicate that none of the testing methods used could be prioritized over others to determine the resistance of AAS against the action of sulfur dioxide. For this reason, the durability testing of AAS remains an issue, and the development of specific standards considering the behavior of AAS seems necessary.  相似文献   
13.
The objective of the study was to assess and perceive the vocal and pharyngeal symptoms and acoustic changes of voice after short-term endotracheal intubation and to evaluate the relation between these changes and the endotracheal tube parameters, number of intubation attempts, duration of anaesthesia, experience of anaesthesiologist. A total of 108 patients were evaluated preoperatively, 1–2 and 24 h after extubation. The vocal and pharyngeal symptoms, voice acoustic characteristics and maximum phonation time (MPT) were evaluated to find the relationship with endotracheal tube parameters, number of intubation attempts, duration of anaesthesia, experience of anaesthesiologist. All vocal and pharyngeal symptoms increased significantly at 24 h and remained significantly increased at 24 h after general anaesthesia. The vocal acoustic parameters changed significantly at 1–2 h: decrease of MPT and increase relative average perturbation were recorded. The day after the short-term intubation: only noise to harmony ratio and habitual pitch remains significantly changed. The most important endotracheal tube parameters that affect significantly (P value <0.05) the vocal function were the size of tube, cuff volume and number of intubation attempts. In relation to the anaesthesia, the changes of the acoustic parameters did not associate significantly with the anaesthesia-related parameters. No statistically significant relationship between experience of an anaesthesiologist and changes of the voice after anaesthesia was detected. Though being short-term, endotracheal anaesthesia is an invasive procedure, and its temporary influence on vocal function is important.  相似文献   
14.
Clinical and psychosocial factors associated separately with primary and secondary fatigue in Parkinson’s disease (PD) patients have not been thoroughly studied before. The aim of our study was to assess factors associated with different fatigue domains in groups with primary and secondary fatigue in PD separately. We divided 165 non-demented PD patients according to the absence/presence of depression, anxiety and excessive somnolence into groups with primary fatigue (N = 63) and with secondary fatigue (N = 102). Fatigue domains examined using the multidimensional fatigue inventory were associated through multiple linear regression analyses for each group separately with sociodemographic data, disease duration, functional status as assessed by the Unified Parkinson’s Disease Rating Scale, treatment, depression, anxiety, excessive somnolence and sleep quality. Out of the assessed non-motor symptoms, fatigue was the most frequent (77.6 %). The prevalence of fatigue in the secondary fatigue group was significantly higher than in the primary fatigue group. Both fatigue groups differed significantly in factors associated with different fatigue domains. Functional status or other disease-related factors were not associated with primary fatigue. In the secondary fatigue group, we found associations between some fatigue domains and functional status, older age, male gender and higher anxiety scores. To our knowledge, this is the first study to separately describe clinical determinants and psychosocial factors associated with different fatigue domains in primary and secondary fatigue in PD, underlining the importance of distinguishing primary and secondary fatigue in future PD studies and clinical practice.  相似文献   
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16.
The purpose of this study is to assess the efficacy and safety of the selective serotonin-reuptake inhibitor (SSRI) citalopram in depressed epileptic patients. We evaluated 43 epileptic patients who suffered from depression and whose total score on the 21 items of the Hamilton Scale for Depression (HAMD 21) exceeded 15 points. These patients were examined by the psychiatrist and scaled before treatment and after 4 and 8 weeks of treatment with citalopram. The dose of citalopram was flexible, related to the actual condition of the patient. In each patient and in the whole group of patients we compared the monthly seizure frequency (total, partial seizures, generalized tonic–clonic seizures) recorded during treatment with citalopram with that recorded during the 2 months preceding the start of citalopram. During treatment we observed a decrease in the total score on the HAMD 21 from a mean initial value of 21.5 ± 2.9 (range, 17–26) prior to therapy 14.5 ± 2.9 (range, 10–19) (P < 0.001) after 4 weeks of treatment and to 9.9 ± 3.1 (range, 4–19) (P < 0.001) after 8 weeks of treatment. There were 9 (20.9%) responders after 4 weeks of treatment and 28 responders (65.1%) after 8 weeks, all of them with decrease on the HAMD 21 greater than 50%. Nausea was the most common adverse event in 7 patients (16.3%) during the first month of treatment and in 3 patients (6.9%) during the second month of treatment. Sexual dysfunction (decrease of libido) was reported in 2 (4.7%) male patients during the entire course of treatment. No seizure worsening was observed in our patients. Monthly seizure frequency did not change significantly: 2.24 (±0.76) seizures before treatment with citalopram, 2.29 (±0.81) seizures in the first month of treatment, 2.21 (±1.00) seizures in the second month of treatment. No occurrence of de novo generalized tonic–clonic seizures was recorded in individual patients. Citalopram is a safe and effective antidepressant in the treatment of depressed epileptic patients.  相似文献   
17.
The outlying mean index (OMI) method was used to test for seasonal microhabitat partitioning in Pseudodactylogyrus anguillae and Pseudodactylogyrus bini communities parasitising European eel ( Anguilla anguilla L.) in four seasons. No differences in the occurrence of parasites were found in different seasons or on different gill arches. The OMI analysis showed that hemibranch separation and gill segments were the main factors explaining the variation in parasite niche occupation for the first factorial axis, which was generally more significant than the second factorial axis. The OMI and tolerance indices were compared for both species in the seasons studied, and the main differences between species indices were recorded. P. anguillae and P. bini communities were partitioned in the seasons with high epidemiological parameters of the infection. In the seasons with low epidemiological parameters, or in seasons when the parasite species preferred gill arches, the characters of gill division (lower level of gill division than gill arches) were not important for the partitioning of the Pseudodactylogyrus communities.  相似文献   
18.
19.
The majority of nonantibacterial activities discovered for beta-lactam derivatives during the last 15 years are based on their ability to form a stable covalent complex with nucleophile in the active site of enzymes regulating fundamental physiological processes in mammalian organism such as serine and cysteine proteases, LDL phospholipase A(2), A-independent transacylase and some still indeciphered enzymes. Regulation of their catalytic activity both in vitro and in vivo by compounds designed on the cephalosporin, penicillin and 2-azetidinone base was successfully exploited in the treatment of inflammatory, respiratory, cardiovascular disorders, cancer and other pathologic processes. Availability of X-ray crystallographic data for target enzymes and computational molecular modelling in combination with wide possibilities of structural modifications for commercial natural and synthetic beta-lactams and the chiral blocks allow to consider this class of organic compounds as a perspective source of mechanism based nonantibacterial drugs.  相似文献   
20.
Dendritic cells (DCs) are antigen-presenting cells that play a critical role in the induction of cytotoxic T-lymphocytes. An optimal method for the generation of DC for clinical use remains to be established. The aim of our study was to find an optimal cytokine combination for DC generation from peripheral blood stem cells (PBSC) and peripheral blood mononuclear cells (PBMC) in serum-free conditions. Serial immunophenotyping enabled us to observe changes in DC content during the culture as well as the development of maturation and activation markers. As a source for DC culture, we used PBSC from patients with multiple myeloma after stem cell mobilization using cyclophosphamide and G-CSF, or PBMC from healthy donors without mobilization. The cells were cultured in a serum-free medium with different cytokine combinations including GM-CSF, TNF-alpha, Flt-3, CD40L, IFN-gamma, IL-1alpha, IL-6, PGE1, and IL-4. The cell cultures were evaluated by immunophenotyping. For PBMC, interleukin-12 assay was performed. For PBSC, the yield of DC as determined by CD83+ cell count ranged from 0. 6 x 10(5) to 30.1 x 10(4) (mean: 9.4 x 10(4)) of DC generated per 1 x 10(6) of initially plated nucleated cells from apheresis. This yield corresponded to (0.3-19.1) x 10(5) (mean: 4.3 x 10(5)) per 1 x 10(6) of CD34+ cells in the apheresis products. For PBMC, the yield was (0.4-24.8) x 10(4) (mean: 2.4 x 10(4)) of DC generated per 1 x 10(6) of initially plated mononuclear cells from venous blood. The cultured cells expressed the mature immunophenotype. No significant differences in cell yield or immunophenotype were detected when comparing different cytokine combinations.  相似文献   
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