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1.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
2.
In this paper, an antimycobacterial component of extracellular metabolites of a gut bacterium Raoultella ornithinolytica from D. veneta earthworms was isolated and its antimycobacterial action was tested using Mycobacterium smegmatis. After incubation with the complex obtained, formation of pores and furrows in cell walls was observed using microscopic techniques. The cells lost their shape, stuck together and formed clusters. Surface‐enhanced Raman spectroscopy analysis showed that, after incubation, the complex was attached to the cell walls of the Mycobacterium. Analyses of the component performed with Fourier transform infrared spectroscopy demonstrated high similarity to a bacteriocin nisin, but energy dispersive X‐ray spectroscopy analysis revealed differences in the elemental composition of this antimicrobial peptide. The component with antimycobacterial activity was identified using mass spectrometry techniques as a glycolipid–peptide complex. As it exhibits no cytotoxicity on normal human fibroblasts, the glycolipid–peptide complex appears to be a promising compound for investigations of its activity against pathogenic mycobacteria.  相似文献   
3.
Psychiatric Quarterly - In the modern day, it is important to identify the determinants of Facebook addiction and game disorder. The main aim of our study is to examine the relationship between...  相似文献   
4.
Inflammation Research - A tumor growth depends on the potency of the tumor to support itself with nutrients and oxygen. The development of a vascular network within the tumor is key to its...  相似文献   
5.

Background

The removal of the olfactory bulbs has been attributed to behavioral changes and neuroplasticity manifesting themselves among others like increases in brain neurotrophin expression and neurogenesis. Earlier data presented that EMD386088, a 5-HT6 receptor partial agonist, exerts antidepressant-like properties after chronic administration in olfactory bulbectomy (OB) model as was it compared with amitriptyline (AMI). The aim of this study was to compare acute and chronic biochemical effects of EMD386088, administered in its antidepressant active (2.5 mg/kg) and non-active (1.25 mg/kg) doses, found in the open field test in OB rats, with those of AMI (10 mg/kg). The levels of 5-HT6 receptor protein and selected neurotrophins in prefrontal cortex (PFC) and hippocampus (Hp) of rats have been examined.

Methods

5-HT6 receptor protein and selected neurotrophins: brain-derived neurotrophic factor (BDNF), cAMP-response element binding protein (CREB), the product of the immediate early gene c-fos (cFos) protein levels were assessed using a Western blot analysis in PFC and Hp of bulbectomized rats after acute or chronic (14-day) EMD386088 or AMI intraperitoneal (ip) treatment.

Results

The acute treatment with EMD386088 caused significant increases in CREB and BDNF protein levels in PFC, and an increase in BDNF in Hp of OB rats, while AMI injection decreased CREB and did not change BDNF levels. After the chronic administration of EMD386088, the increasing levels of BDNF and CREB were still observed in PFC and Hp.

Conclusions

The antidepressant-like effect of EMD386088 may be associated with the neuroplasticity activation in PFC and Hp in rats.  相似文献   
6.
Objective: The pathogenesis of idiopathic growth hormone deficiency (GHD) in children, including possible cerebral metabolic alterations, remains unclear. The aim of the study was to evaluate metabolic changes within the normal appearing brain in children with GHD using MR spectroscopy (MRS) and to correlate MRS measurements with hormonal concentrations and with pituitary gland size. Methods: Seventy children with GHD (mean age 7.8 yrs) and 11 healthy controls (mean age 8.4 yrs) were enrolled in the study. The MRS examinations were performed on a 1.5T scanner. Voxels were located in the posterior cingulate gyrus (PCG) and the left parietal white matter (PWM). The NAA/Cr, Cho/Cr and mI/Cr ratios were analyzed. The metabolite ratios, pituitary gland size and hormonal concentrations: growth hormone (GH) in two stimulation tests and GH during the night, as well as IGF-1 (insulin-like growth factor) and IGFBP3 (insulin-like growth factor-binding protein) levels were also correlated. Results: There was a significant (p < 0.05) decrease of the NAA/Cr ratios in PCG and PWM in children with GHD compared to the normal subjects. Other metabolite ratios showed no significant differences. We also found significant positive correlations between NAA/Cr ratio in PWM and IGFBP3 level, as well as with GH concentration in a stimulation test with glucagon. Conclusions: The reduction of NAA/Cr ratios may suggest loss of neuronal activity within normal appearing gray and white matters in children with GHD. MRS could be a sensitive marker of cerebral metabolic disturbances associated with GHD and maybe used as an additional indicator for therapy with recombinant GH.  相似文献   
7.
Previous imaging studies that investigated morphometric group differences of subcortical regions outside the substantia nigra between non‐demented Parkinson's patients and controls either did not find any significant differences, or reported contradictory results. Here, we performed a comprehensive morphometric analysis of 20 cognitively normal, early‐stage PD patients and 19 matched control subjects. In addition to relatively standard analyses of whole‐brain grey matter volume and overall regional volumes, we examined subtle localized surface shape differences in striatal and limbic grey matter structures and tested their utility as a diagnostic marker. Voxel‐based morphometry and volumetric comparisons did not reveal significant group differences. Shape analysis, on the other hand, demonstrated significant between‐group shape differences for the right pallidum. Careful diffusion tractography analysis showed that the affected parts of the pallidum are connected subcortically with the subthalamic nucleus, the pedunculopontine nucleus, and the thalamus and cortically with the frontal lobe. Additionally, microstructural measurements along these pathways, but not along other pallidal connections, were significantly different between the two groups. Vertex‐wise linear discriminant analysis, however, revealed limited accuracy of pallidal shape for the discrimination between patients and controls. We conclude that localized disease‐related changes in the right pallidum in early Parkinson's disease, undetectable using standard voxel‐based morphometry or volumetry, are evident using sensitive shape analysis. However, the subtle nature of these changes makes it unlikely that shape analysis alone will be useful for early diagnosis. Hum Brain Mapp 35:1681–1690, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
8.
In many published studies, various modifications of the flanker task have been used. Regardless of the flanker task version, the conflict N2 component has been consistently reported and interpreted as evidence for the resolution of conflict introduced by incongruent flankers. However, ERP studies that used the most basic flanker task (i.e., a version with equiprobable congruent and incongruent conditions in which only congruency between the target and flankers is manipulated) have not provided compelling evidence for the conflict N2 component. We report the results of a large‐sample ERP study employing a basic flanker task that allowed us to revisit the mechanism underlying the resolution of conflict introduced by incongruent flankers. In the behavioral data, we observed the classic effect of congruency. In the ERP data, we found three conflict‐sensitive components: (a) an early frontal component, presumably corresponding to P2, (b) P300 for congruent trials, followed by (c) P300 for incongruent trials. We did not find evidence for the conflict N2 component. Based on a review of literature, we propose that the conflict N2 component observed in a basic flanker task might be a frontal aspect of the P300 component. Given previous attempts to attribute the functional role of the ERP components, the absence of the conflict N2 in the basic flanker task suggests that response inhibition may not be crucial for the resolution of conflict induced by incongruent flankers. Instead, the P2 component appears to indicate that selective attention might play an important role in resolving the flanker conflict.  相似文献   
9.

Objective

Exposure to air particulate matter (PM) is associated with chronic inflammatory and autoimmune diseases. Macrophages are responsible for the regulation of chronic inflammation. However, whether PM affects macrophage polarization remains unclear. The aim of this study was to evaluate whether nontoxic concentrations of urban PM are able to prime macrophages to altered inflammatory response upon LPS challenge.

Methods

We used two forms of the urban particulate matter SRM 1648a, intact PM and PM deprived of organic compounds (PM?C). Peritoneal murine macrophages were exposed to different concentrations of PM for 24 h and then challenged with LPS. Production of inflammatory mediators by macrophages was measured to test immunostimulatory/priming capacity of PM.

Results

Particulate matter used at non-cytotoxic concentrations induced a dose-dependent production of proinflammatory cytokines (TNF-α, IL-6, IL-12p40). By contrast, PM?C were not able to stimulate macrophages. However, macrophages primed with both forms of PM show proinflammatory response upon LPS challenge.

Conclusions

Our data indicate that exposure of macrophages to low concentrations of PM may prime the cells to hyperinflammatory response upon contact with LPS. Further studies are necessary to explain whether the exposure of patients suffering from chronic inflammatory diseases to particulate matter is responsible for the exacerbation of clinical symptoms during bacterial infections.
  相似文献   
10.
Context: Crataegus monogyna L. (Rosaceae) (CM), Equisetum telmateia L. (Equisataceae) (ET), Geranium purpureum Vil. (Geraniaceae) (GP), Mentha suaveolens Ehrh. (Lamiaceae) (MS), and Lavandula stoechas L. spp. luisieri (Lamiaceae) (LS) are all medicinal.

Objective: To evaluate the antioxidant, antiproliferative and antimicrobial activities of plant extracts and quantify individual phenolics and zinc.

Material and methods: Aerial part extracts were prepared with water (W), ethanol (E) and an 80% mixture (80EW). Antioxidant activity was measured with TAA, FRAP and RP methods. Phenolics were quantified with a HPLC. Zinc was quantified using voltammetry. Antibacterial activity (after 48?h) was tested using Enterococcus faecalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Listeria monocytogenes. Antiproliferative activity (after 24?h) was tested using HEP G2 cells and fibroblasts.

Results: Solvents influenced results; the best were E and 80EW. GP had the highest antioxidant activity (TAA and FRAP of 536.90?mg AAE/g dw and 783.48?mg TE/g dw, respectively). CM had the highest zinc concentration (37.21?mg/kg) and phenolic variety, with neochlorogenic acid as the most abundant (92.91?mg/100?g dw). LS was rich in rosmarinic acid (301.71?mg/100?g dw). GP and LS inhibited the most microorganisms: B. cereus, E. coli and S. aureus. GP also inhibited E. faecalis. CM had the lowest MIC: 5830?μg/mL. The antibacterial activity is explained by the phenolics present. LS and CM showed the most significant anti-proliferative activity, which is explained by their zinc content.

Conclusion: The most promising plants for further studies are CM, LS and GP.  相似文献   
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