Correction to: Who is the ocean? Preface to the future seas 2030 special issue

Reviews in Fish Biology and Fisheries - A correction to this paper has been published: https://doi.org/10.1007/s11160-021-09657-9     

Intraindividual validation of heart rate variability indexes to measure vagal effects on hearts

Heart rate variability (HRV) has been widely used as a measure of vagal activation in physiological, psychological, and clinical examinations. We studied the within-subject quantitative relationship between HRV and vagal effects on the heart in different body postures during a gradually decreasing vagal blockade. Electrocardiogram and respiratory frequency were measured in subjects (8 endurance athletes and 10 participants of nonendurance sports) in supine, sitting, and standing postures before the blockade, under vagal blockade (atropine sulfate, 0.04 mg/kg), and four times during a 150-min recovery from the blockade. Fast Fourier transform was used to calculate low-frequency power (LFP, 0.04-0.15 Hz), high-frequency power (HFP, 0.15-0.40 Hz), and total power (TP, 0.04-0.40 Hz). A within-subject linear regression analysis of recovery time on each HRV index was conducted. Complete vagal blockade decreased all HRV significantly, particularly HFP (P < 0.001). A linear fit explained a large portion of the within-subject variance between recovery time and natural log-transformed (ln) HRV indexes in every posture, with coefficients of determination (R2) in the supine posture [means (SD)]: 98 (SD 2)% for mean R-R interval, 87 (SD 10)% for lnLFP, 87 (SD 13)% for lnHFP, and 91 (SD 10)% for lnTP. Neither body posture nor endurance-training background had an impact on R2 values. There was marked between-subject variation in the R2 values, slopes, and intercepts. In conclusion, all HRV, particularly HFP, is predominantly under vagal control. Within subjects, lnLFP, lnHFP, and lnTP increased linearly with the gradually decreasing vagal blockade in all postures.     

Bifidobacterium microbiota and parameters of immune function in elderly subjects

Faecal and serum samples were collected over a period of 6 months from 55 institutionalized elderly subjects, who were enrolled in a double-blind placebo-controlled study. Participants were randomized in one of the three treatment groups: intervention (two probiotic Bifidobacterium longum strains: 2C and 46), placebo and commercial control (Bifidobacterium lactis Bb-12). The faecal Bifidobacterium microbiota was characterized by genus and species-specific PCR. Serum levels of the cytokines IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1 were determined by enzyme-linked immunosorbent assay. Each participant harboured on average approximately three different bifidobacterial species. The most frequently detected species were B. longum, Bifidobacterium adolescentis and Bifidobacterium bifidum. Depending on the treatment, the intervention resulted in specific changes in the levels of certain Bifidobacterium species, and positive correlations were found between the different species. Negative correlations were observed between the levels of Bifidobacterium species and the pro-inflammatory cytokine TNF-alpha and the regulatory cytokine IL-10. The presence of faecal B. longum and Bifidobacterium animalis correlated with reduced serum IL-10. The anti-inflammatory TGF-beta1 levels were increased over time in all three groups, and the presence of Bifidobacterium breve correlated with higher serum TGF-beta1 levels. This indicates that modulation of the faecal Bifidobacterium microbiota may provide a means of influencing inflammatory responses.     

Palmitoyl protein thioesterase 1 (PPT1) deficiency causes endocytic defects connected to abnormal saposin processing

Infantile neuronal ceroid lipofuscinosis (INCL) is a severe neurodegenerative disorder of the childhood caused by mutations in the gene encoding palmitoyl protein thioesterase 1 (PPT1). PPT1 localizes to late endosomes/lysosomes of non-neuronal cells and in neurons also to presynaptic areas. PPT1-deficiency causes massive death of cortical neurons and most tissues show an accumulation of saposins A and D. We have here studied endocytic pathways, saposin localization and processing in PPT1-deficient fibroblasts to elucidate the cellular defects resulting in accumulation of specific saposins. We show that PPT1-deficiency causes a defect in fluid-phase and receptor-mediated endocytosis, whereas marker uptake and recycling endocytosis remain intact. Furthermore, we show that saposins A and D are more abundant and relocalized in PPT-deficient fibroblasts and mouse primary neurons. Metabolic labeling and immunoprecipitation analyses revealed hypersecretion and abnormal processing of prosaposin, implying that the accumulation of saposins may result from endocytic defects. We show for the first time a connection between saposin storage and a defect in the endocytic pathway of INCL cells. These data provide new insights into the metabolism of PPT1-deficient cells and offer a basis for further studies on cellular processes causing neuronal death in INCL and other neurodegenerative diseases.     

Hepatitis C virus core, NS3, NS4B and NS5A are the major immunogenic proteins in humoral immunity in chronic HCV infection

Background

Light-dependent activities against enveloped viruses in St. John's Wort (Hypericum perforatum) extracts have been extensively studied. In contrast, light-independent antiviral activity from this species has not been investigated.

Results

Here, we identify the light-independent inhibition of human immunodeficiency virus-1 (HIV-1) by highly purified fractions of chloroform extracts of H. perforatum. Both cytotoxicity and antiviral activity were evident in initial chloroform extracts, but bioassay-guided fractionation produced fractions that inhibited HIV-1 with little to no cytotoxicity. Separation of these two biological activities has not been reported for constituents responsible for the light-dependent antiviral activities. Antiviral activity was associated with more polar subfractions. GC/MS analysis of the two most active subfractions identified 3-hydroxy lauric acid as predominant in one fraction and 3-hydroxy myristic acid as predominant in the other. Synthetic 3-hydroxy lauric acid inhibited HIV infectivity without cytotoxicity, suggesting that this modified fatty acid is likely responsible for observed antiviral activity present in that fraction. As production of 3-hydroxy fatty acids by plants remains controversial, H. perforatum seedlings were grown sterilely and evaluated for presence of 3-hydroxy fatty acids by GC/MS. Small quantities of some 3-hydroxy fatty acids were detected in sterile plants, whereas different 3-hydroxy fatty acids were detected in our chloroform extracts or field-grown material.

Conclusion

Through bioguided fractionation, we have identified that 3-hydroxy lauric acid found in field grown Hypericum perforatum has anti-HIV activity. This novel anti-HIV activity can be potentially developed into inexpensive therapies, expanding the current arsenal of anti-retroviral agents.     

Empowering her guardians to nurture our Ocean’s future

Reviews in Fish Biology and Fisheries - Coastal Indigenous and Traditional communities are starting to see changes to their lives from climate change, whether this is from species range changes or...     

Poleward bound: adapting to climate-driven species redistribution

Reviews in Fish Biology and Fisheries - One of the most pronounced effects of climate change on the world’s oceans is the (generally) poleward movement of species and fishery stocks in...     

Rapid homogeneous PCR assay for the detection of Chlamydia trachomatis in urine samples

Chlamydia trachomatis infection is the most common bacterial sexually transmitted disease and a major public health problem worldwide. Fast and sensitive point-of-care diagnostics including non-invasive sample collection would be of value for the prevention of C. trachomatis transmission. The aim of this study was to develop a fast, reliable, non-invasive and easy-to-use homogenous PCR assay for the detection of C. trachomatis. Bacteria were concentrated from urine by a simple and fast centrifugation-based urine pretreatment method. Novel automated GenomEra technology was utilized for the rapid closed-tube PCR including time-resolved fluorometric detection of the target using lanthanide chelate labeled probes. We have developed a rapid C. trachomatis assay which provides qualitative results in 1 h with diagnostic sensitivity and specificity of 98.7% and 97.3%, respectively. The novel assay can be performed with minimal laboratory expertise and without sophisticated DNA-extraction devices and has performance comparable to current gold standard assays.     

Exercise rehabilitation on home-dwelling patients with Alzheimer's disease - a randomized, controlled trial. Study protocol

Background

The Turkish population living in the Netherlands has a high prevalence of psychological complaints and has a high threshold for seeking professional help for these problems. Seeking help through the Internet can overcome these barriers. This project aims to evaluate the effectiveness of a guided self-help problem-solving intervention for depressed Turkish migrants that is culturally adapted and web-based.

Methods

This study is a randomized controlled trial with two arms: an experimental condition group and a wait list control group. The experimental condition obtains direct access to the guided web-based self-help intervention, which is based on Problem Solving Treatment (PST) and takes 6 weeks to complete. Turkish adults with mild to moderate depressive symptoms will be recruited from the general population and the participants can choose between a Turkish and a Dutch version. The primary outcome measure is the reduction of depressive symptoms, the secondary outcome measures are somatic symptoms, anxiety, acculturation, quality of life and satisfaction. Participants are assessed at baseline, post-test (6 weeks), and 4 months after baseline. Analysis will be conducted on the intention-to-treat sample.

Discussion

This study evaluates the effectiveness of a guided problem-solving intervention for Turkish adults living in the Netherlands that is culturally adapted and web-based.

Trial Registration

Nederlands Trial Register: NTR2303