Fast and User-Friendly Detection of Flatfish Species (Pleuronectes platessa and Solea solea) via Loop-Mediated Isothermal Amplification (LAMP).

The detection of a Cytochrome b gene (cytb) for species differentiation in fish is intensively used. A fast alternative to expensive and time-consuming DNA barcoding is loop-mediated isothermal amplification (LAMP) in combination with efficient readout systems. For this reason, we developed LAMP assays for rapid species detection of Pleuronectes platessa and Solea solea, two economically important flatfish species in Europe that are prone to mislabeling. Species-specific primer sets targeting cytb were designed, and LAMP assays were optimized. With the optimized LAMP assays, we were able to detect up to 0.1 and 0.01 ng of target DNA of P. platessa and S. solea, respectively, and in each case up to 1% (w/w) of target species in mixtures with nontarget species. For future on-site detection, a lateral flow assay and a pocket-sized lab-on-phone assay were used as readout systems. The lab-on-phone assay with the S. solea specific primer set revealed cross-reactivity to Solea senegalensis. The assay targeting P. platessa proved to be highly specific. Both assays could be performed within 45 min and provided rapid and easy detection of fish species.

A next-generation sequencing approach for the detection of mixed species in canned tuna.

Tuna cans are relevant seafood products for which mixtures of different tuna species are not allowed according to European regulations. In order to support the prevention of food fraud and mislabelling, a next-generation sequencing methodology based on mitochondrial cytochrome b and control region markers has been tested. Analyses of defined mixtures of DNA, fresh tissue and canned tissue revealed a qualitative and, to some extent, semiquantitative identification of tuna species. While the choice of the bioinformatic pipeline had no influence in the results (p = 0.71), quantitative differences occurred depending on the treatment of the sample, marker, species, and mixture (p < 0.01). The results revealed that matrix-specific calibrators or normalization models should also be used in NGS. The method represents an important step towards a semiquantitative method for routine control of this analytically challenging food matrix. Tests of commercial samples uncovered mixed species in some cans, being not in compliance with EU regulations.

Early intervention, treatment and rehabilitation of employees with common mental disorders by using psychotherapeutic consultation at work: study protocol of a randomised controlled multicentre trial (friaa project).

BACKGROUND: Common mental disorders are one of the leading causes for sickness absence and early retirement due to reduced health. Furthermore, a treatment gap for common mental disorders has been described worldwide. Within this study, psychotherapeutic consultation at work defined as a tailored, module-based and work-related psychotherapeutic intervention will be applied to improve mental health care. METHODS: This study comprises a randomised controlled multicentre trial with 1:1 allocation to an intervention and control group. In total, 520 employees with common mental disorders shall be recruited from companies being located around five study centres in Germany. Besides care as usual, the intervention group will receive up to 17 sessions of psychotherapy. The first session will include basics diagnostics and medical indication of treatment and the second session will include work-related diagnostics. Then, participants of the intervention group may receive work-related psychotherapeutic consultation for up to ten sessions. Further psychotherapeutic consultation during return to work for up to five sessions will be offered where appropriate. The control group will receive care as usual and the first intervention session of basic diagnostics and medical indication of treatment. After enrolment to the study, participants will be followed up after nine (first follow-up) and fifteen (second follow-up) months. Self-reported days of sickness absence within the last 6 months at the second follow-up will be used as the primary outcome and self-efficacy at the second follow-up as the secondary outcome. Furthermore, a cost-benefit assessment related to costs of common mental disorders for social insurances and companies will be performed. DISCUSSION: Psychotherapeutic consultation at work represents a low threshold care model aiming to overcome treatment gaps for employees with common mental disorders. If successfully implemented and evaluated, it might serve as a role model to the care of employees with common mental disorders and might be adopted in standard care in cooperation with sickness and pension insurances in Germany. TRIAL REGISTRATION: The friaa project was registered at the German Clinical Trial Register (DRKS) at 01.03.2021 (DRKS00023049): https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00023049 .

Tuna labels matter in Europe: Mislabelling rates in different tuna products.

Tuna fisheries and processing represent economic activities of paramount importance around the world. Most of these products are traded for human consumption and in general are highly demanded commodities. However, not all tuna products achieve the same market price, some consumers are willing to pay a huge amount of money for certain species (i.e. Japanese market for Bluefin tuna) while other species are rather affordable (i.e. Skipjack tuna), therefore mislabelling has been observed frequently. We collected and analysed 545 tuna samples in six European countries, including fresh, frozen and canned products, and we have investigated whether or not these products were correctly labelled under European and national legislations. We found an overall mislabelling rate of 6.79%; in particular, 6.70% of the fresh and frozen tuna products and 7.84% of canned tuna were mislabelled, and only in the case of fresh and frozen tuna samples significant differences among countries were found. Mislabelling rates for Atlantic Bluefin tuna labelled products were very high, ranging from 50 up to 100%. In general, mislabelling was higher when specific names were included in the labels. The "tuna" umbrella term is a very popular one with consumers, but also one that remains vulnerable to ambiguity, hampering efforts towards market transparency and with potential negative consequences to the adequate management of tuna species stocks.

Species identification in mixed tuna samples with next-generation sequencing targeting two short cytochrome b gene fragments.

Conventional Sanger sequencing of PCR products is the gold standard for species authentication of seafood products. However, this method is inappropriate for the analysis of products that might contain mixtures of species, such as tinned tuna. The purpose of this study was to test whether next-generation sequencing (NGS) can be a solution for the authentication of mixed products. Nine tuna samples containing mixtures of up to four species were prepared and subjected to an NGS approach targeting two short cytochrome b gene (cytb) fragments on the Illumina MiSeq platform. Sequence recovery was precise and admixtures of as low as 1% could be identified, depending on the species composition of the mixtures. Duplicate samples as well as two individual NGS runs produced very similar results. A first test of three commercial tinned tuna samples indicated the presence of different species in the same tin, although this is forbidden by EU law.

Natural Chemical Composition of Commercial Fish Species: Characterisation of Pangasius, Wild and Farmed Turbot and Barramundi.

To comply with the relevant legal requirements and correct labelling, it is necessary for business operators and inspection authorities to know the natural characteristics of the raw material. This study gives a comprehensive overview of muscle flesh composition of farmed and wild Atlantic turbot (Scophthalmus maximus) and barramundi (Lates calcarifer) and of farmed pangasius (Pangasianodon hypophthalmus). The proximate composition, di- and triphosphates and citric acid values are presented in order to evaluate possible indicators for a hidden treatment during processing to fillets. All moisture contents were ≤80%. Even for pangasius, protein values for deep skinned fillets of ≥18% were determined. Only small quantities of naturally occurring citric acid (up to 0.03 g·kg-1) were detectable. The lipid content was the most varying main component within the different species, ranging between 1.2% to 2.0% and 0.3% to 3.0% for farmed turbot and barramundi, respectively. Pangasius flesh had a mean lipid content of 7.8%. Trimming and separation of the red layer reduced the lipid content of the commercially sold white-flesh fillets to 2.7% to 3.5%. Fatty acids profiles, free amino acids, and minerals were analysed to show the nutritional quality of the aquaculture fish species and compared to wild turbot and barramundi. Despite some natural variation, these components can be considered as comparable.

Meat Composition and Quality Assessment of King Scallops (Pecten maximus) and Frozen Atlantic Sea Scallops (Placopecten magellanicus) on a Retail Level.

An enlarged range of scallop products on the market allows the consumer to buy lower priced alternatives, which often raises the question of quality and control. Frozen meat of king scallops (Pecten maximus) and Atlantic sea scallops (Placopecten magellanicus) were purchased on the German market and compared with fresh shell-on king scallops of various origin. The approximate composition, inclusive citric acid and phosphates, minerals, free amino acids (FAA) and fatty acid profiles were examined in the muscle to identify changes as a result of processing. The FAA glycine and taurine as well the fatty acids 20:5n-3 (EPA) and 22:6n-3 (DHA) were the most abundant, but were reduced in processed samples. Di- and triphosphate contents were not detectable (<0.01 g·kg-1) in untreated meats. Most frozen scallop products contained added citrates and polyphosphates and had distinctly higher water contents (up to 89%) and an increased moisture to protein ratio (M/P) (up to 9) compared with the fresh king scallops (78%, M/P < 5). Labelling of species, verified by PCR-based DNA analysis, and ingredients were not correct in each case. Overall results indicated no relevant differences in mineral content, except high sodium contents, resulting from additives. Labelling does not readily allow the consumer to recognize the extent of processing effects.

Transcranial sonography in the premotor diagnosis of Parkinson's disease.

Substantia nigra hyperechogenicity (SN+) is a common finding in transcranial ultrasound studies of parkinsonian patients. However, this echofeature is also found in 10% of healthy controls and is here associated with PD risk factors such as male gender and positive family history for PD, as well as with putative premotor symptoms such as hyposmia, depression, sleep disturbances, and subtle neuropsychological and motor impairment. SN+ is hypothesized to indicate an increased risk to develop PD during lifetime. PET studies substantiate this hypothesis, given that SN+ controls showed reduced striatal [(18)Fluoro] Dopa uptake in PET studies. First results of longitudinal follow-up studies show a higher relative risk for future PD in SN+ asymptomatic individuals.

Evidence for shoulder girdle dystonia in selected patients with cervical disc prolapse.

Some patients with cervical disc herniation suffer from persistent nuchal pain and muscle spasms after decompressive surgery despite the lack of clinical and radiological signs for actual spinal root compression. Sonographic examination of the brain in some of these patients showed increased echogenicity of the lentiform nuclei as described in patients with idiopathic dystonia. This has been linked to an altered Menkes protein level and copper metabolism. We suggest a relationship between persistent nuchal pain after adequate cervical disc surgery and dystonic movement disorders. Thirteen patients with persistent nonradicular nuchal pain after at least one cervical disc surgery and without evidence of continuing spinal root compression and 13 age-matched controls were included. All patients had a complete neurological examination, ultrasound, and MRI scan of the brain. In addition, Menkes protein mRNA levels of leucocytes were analyzed in patients and controls. All patients with persistent nuchal pain exhibited a constant tonic unilateral shoulder elevation associated with an ipsilateral hypertrophy of the trapezius muscle. Ultrasound examination showed an increased echogenicity of the lentiform nucleus in one patient unilaterally and in 10 patients bilaterally but in none of the controls. On MRI the T2-values of the lentiform nuclei were found to be higher in patients exhibiting a hyperechogenicity of the lentiform nuclei compared to controls (P = 0.01). In addition, Menkes protein mRNA levels were decreased in patients with cervical disc herniation (P = 0.03). Clinical, neuroimaging, and biochemical findings of this selected patient sample with chronic nuchal pain and muscle spasms after cervical disc surgery resemble alterations in patients with idiopathic cervical dystonia. This suggests a link between both disorders. A peripheral trauma to the nerve roots may precipitate dystonic movements in susceptible patients and chronic dystonic muscle contraction would account for the persistent nuchal pain.

Echogenicity of the substantia nigra: association with increased iron content and marker for susceptibility to nigrostriatal injury.

BACKGROUND: Patients with Parkinson disease characteristically exhibit an increased echogenicity of the substantia nigra (SN) on transcranial sonography, a new neuroimaging technique. The same echo feature of the SN can be identified in 9% of healthy adults. OBJECTIVE: To evaluate the relevance of the echogenic SN in healthy adults. DESIGN: In the first part of the study, 10 healthy subjects younger than 40 years with a distinct SN hyperechogenicity underwent extensive neurological, motor, neuropsychological, and fluorine 18-dopa positron emission tomographic ([18F]-dopa PET) examinations. Results were compared with those of 10 subjects with a low echogenic SN. In the second part of the study, the postmortem brains of 20 patients without extrapyramidal disorders during their lifetime were sonographically examined with a particular focus on SN echogenicity. Subsequently, one half of the brain was prepared for heavy metal analysis, the other for a histological examination. RESULTS: Healthy subjects with SN hyperechogenicity exhibited a significant reduction of the [18F]-dopa uptake, especially in the putamen (Wilcoxon matched pair test: left side, P =.006; right side, P =.009), whereas their neuropsychological and motor performance were normal. Postmortem studies showed that the echogenicity of the SN correlated with its iron content. CONCLUSIONS: Increased echogenicity of the SN, characteristically seen in Parkinson disease, is related to a functional impairment of the nigrostriatal system (even in young healthy adults) that can be revealed by [18F]-dopa PET studies. Substantia nigra hyperechogenicity is related to a higher tissue iron level, which is known to enhance the cells' generation of reactive oxygen specimens. Therefore, we hypothesize that transcranial sonography may identify a susceptibility marker for the development of nigral injury that can be detected early in life, prior to the onset of Parkinson disease.