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Purpose: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface.

Materials and methods: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA).

Results: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts.

Conclusions: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.  相似文献   

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Background: In a military or terrorist scenario, combination of organophosphorus compounds (OP) poisoning with physical trauma requiring surgical treatment and thus general anaesthesia are possible. Previous in vitro studies showed an altered potency of relevant anaesthetics during cholinergic crisis. Hence, it is not clear, which anaesthetics are suitable to achieve the necessary stage of surgical anaesthesia in OP poisoning.

Methods: In the present study, different anaesthetic regimens (ketamine-midazolam, propofol-fentanyl, thiopental-fentanyl), relevant in military emergency medicine, were examined in soman-poisoned rats. Clinical signs and cardiovascular variables were recorded continuously. Blood samples for acetylcholinesterase (AChE) activity were drawn. After euthanasia or death of the animals, brain and diaphragm were collected for cholinesterase assays.

Results: Propofol-fentanyl and thiopental-fentanyl resulted in surgical anaesthesia throughout the experiments. With ketamine-midazolam, surgical anaesthesia without respiratory impairment could not be achieved in pilot experiments (no soman challenge) and was therefore not included in the study. Soman-poisoned and control animals required a comparable amount of propofol-fentanyl or thiopental-fentanyl. In combination with atropine, significantly less propofol was needed. Survival rate was higher with thiopental compared to propofol. Atropine improved survival in both groups. Blood and tissue AChE activities were strongly inhibited after soman administration with and without atropine treatment.

Discussion: The current in vivo study did not confirm concerns of altered potency of existing anaesthetic protocols for the application of propofol or thiopental with fentanyl due to soman poisoning. Despite severe cholinergic crisis, sufficient anaesthetic depth could be achieved in all animals.

Conclusion: Further experiments in in vivo models closer to human pharmaco- and toxicokinetics (e.g., swine) are required for confirmation of the initial findings and for improving extrapolation to humans.  相似文献   

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Objectives: Internet gaming disorder (IGD) is associated with altered physiological reactivity to psychosocial stress. Findings from a previous study on alterations of basal hypothalamic–pituitary–adrenal (HPA) axis functioning, indexed by differences in hair hormone levels (i.e., cortisol) in IGD patients compared to matched controls, were limited by a small sample size.

Methods: Following the protocol of the previous study, male patients with IGD (n?=?31) and controls (n?=?31) matched for age, educational status and smoking were recruited. Sociodemographic and clinical characteristics were assessed using structured interviews and self-reports. Hair samples were taken for the analysis of cortisol, cortisone, testosterone, progesterone, dehydroepiandrosterone (DHEA), and corticosterone.

Results: Groups showed no significant differences on cortisol (d?=??0.10, 95%CI (?0.60; 0.40)), cortisone (d?=??0.10, 95%CI (?0.60; 0.40)), testosterone (d?=??0.00, 95%CI (?0.51; 0.51)), progesterone (d?=??0.46, 95%CI (?0.96; 0.05)), DHEA (d?=??0.04, 95%CI (?0.54; 0.47)) or corticosterone (d?=??0.19, 95%CI (?0.69; 0.32)). Associations between hair hormone concentrations, symptom severity and sociodemographic variables were weak and did not survive correction for multiple testing.

Conclusions: Unlike other psychiatric disorders, effects of IGD and associated psychopathology on basal HPA axis functioning, indexed by hair hormone levels, are negligible. Future studies need to rule out potential effects of sex, age and long-term pathology on these findings.  相似文献   
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Quality of Life Research - ADHD is regarded as a neurodevelopmental disorder associated with deficits in executive functions (EF). The presence of these deficits is associated with increased...  相似文献   
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