Fokus Neurochirurgische Intensivmedizin 2021/2022

Die Anaesthesiologie -     

Oligoarthritis Caused by Borrelia bavariensis,Austria, 2014

A case of Lyme oligoarthritis occurred in an 11-year-old boy in Vienna, Austria. DNA of Borrelia bavariensis was detected by PCR in 2 aspirates obtained from different joints. Complete recovery was achieved after a 4-week course with amoxicillin. Lyme arthritis must be considered in patients from Europe who have persisting joint effusions.     

Chronic Childhood Stress: Psychometric Properties of the Chronic Stress Questionnaire for Children and Adolescents (CSQ-CA) in Three Independent Samples

Stress in children and adolescents is common and related to many developmental problems. However, most studies have made no distinction between temporary or chronic stress due to the lack of a suitable questionnaire. This study tested the factor structure, reliability and validity of the 17-item self-report Chronic Stress Questionnaire for Children and Adolescents (CSQ-CA) in three samples, that is, 717 adolescents from the general population, 161 adolescents of parents with a severe chronic medical condition (CMC) like multiple sclerosis, and 113 adolescents with healthy parents. Results showed that a one-factor solution provided a reasonable fit overall. Reliability was good (α = .80 to .88). Convergent validity was supported by positive relations between total stress scores and internalizing and externalizing problem behaviors, experience of daily hassles, and maladaptive emotion regulation strategies and negative relations with quality of life, happiness, mindfulness, self-esteem, and coping skills. Adolescents from all samples, who themselves had a light CMC like asthma, showed higher chronic stress levels than those without a CMC. In line, adolescents of parents with a severe CMC reported more chronic stress than those of healthy parents, and adolescents with a chronic illness themselves and a parent with a chronic illness, showed the highest scores across the two family types. Overall, this study presents good psychometric properties of the first available measure of chronic stress in children and adolescents.     

Flavonoids inhibit both rice and sheep serotonin N‐acetyltransferases and reduce melatonin levels in plants

The plant melatonin biosynthetic pathway has been well characterized, but inhibitors of melatonin synthesis have not been well studied. Here, we found that flavonoids potently inhibited plant melatonin synthesis. For example, flavonoids including morin and myricetin significantly inhibited purified, recombinant sheep serotonin N‐acetyltransferase (SNAT). Flavonoids also dose‐dependently and potently inhibited purified rice SNAT1 and SNAT2. Thus, myricetin (100 μmol/L) reduced rice SNAT1 and SNAT2 activity 7‐ and 10‐fold, respectively, and also strongly inhibited the N‐acetylserotonin methyltransferase activity of purified, recombinant rice caffeic acid O‐methyltransferase. To explore the in vivo effects, rice leaves were treated with flavonoids and then cadmium. Flavonoid‐treated leaves had lower melatonin levels than the untreated control. To explore the direct roles of flavonoids in melatonin biosynthesis, we first functionally characterized a putative rice flavonol synthase (FLS) in vitro and generated flavonoid‐rich transgenic rice plants that overexpressed FLS. Such plants produced more flavonoids but less melatonin than the wild‐type, which suggests that flavonoids indeed inhibit plant melatonin biosynthesis.     

Antitumour activity of melatonin in a mouse model of human prostate cancer: relationship with hypoxia signalling

Melatonin is known to exert antitumour activity in several types of human cancers, but the underlying mechanisms as well as the efficacy of different doses of melatonin are not well defined. Here, we test the hypothesis whether melatonin in the nanomolar range is effective in exerting antitumour activity in vivo and examine the correlation with the hypoxia signalling mechanism, which may be a major molecular mechanism by which melatonin antagonizes cancer. To test this hypothesis, LNCaP human prostate cancer cells were xenografted into seven‐wk‐old Foxn1nu/nu male mice that were treated with melatonin (18 i.p. injections of 1 mg/kg in 41 days). Saline‐treated mice served as control. We found that the melatonin levels in plasma and xenografted tissue were 4× and 60× higher, respectively, than in control samples. Melatonin tended to restore the redox imbalance by increasing expression of Nrf2. As part of the phenotypic response to these perturbations, xenograft microvessel density was less in melatonin‐treated animals, indicative of lower angiogenesis, and the xenograft growth rate was slower (P < 0.0001). These changes were accompanied by a reduced expression of Ki67, elevated expression of HIF‐1α and increased phosphorylation of Akt in melatonin than saline‐treated mice. We conclude that the beneficial effect of melatonin in reducing cancer growth in vivo was evident at melatonin plasma levels as low as 4 nm and was associated with decreased angiogenesis. Higher HIF‐1α expression in xenograft tissue indicates that the antitumour effect cannot be due to a postulated antihypoxic effect, but may stem from lower angiogenesis potential.