Sarcoid optic neuropathy.

A 45-year-old woman presented with sudden complete vision loss in her left eye and retroorbital pain worsened by eye movements. A previous milder episode of vision loss had occurred in the same eye 1 year before, with complete recovery after high-dose intravenous methylprednisolone. She had no light perception in the left eye with a swollen optic disc, but with a normal right optic disc. There were no systemic manifestations or infections. MR scan of the brain showed extensive enlargement and enhancement of the left optic nerve and optic chiasm. After excluding infections and autoimmune markers, a left optic nerve biopsy confirmed non-caseating granulomas, leading to a diagnosis of neurosarcoidosis.

Regular physical exercise mediates the immune response in atherosclerosis.

Atherosclerosis is a chronic inflammatory cardiovascular disease, which results from lipid accumulation in the blood vessel wall, forming a plaque, and ultimately restricting blood flow. The immune system plays a vital role in progression to plaque rupture. While recent evidence clearly indicates the anti-inflammatory function of regular exercise, the mechanisms by which regular exercise can modulate its pathophysiology is not well understood. In this review, we discuss how regular exercise can lower systemic inflammation directly via modulation of the immune system or indirectly via altered myokine concentrations and metabolites. We describe the exercise-induced responses of various myokines (such as IL-6, adiponectin, and FGF21), and how cell function in the innate immune system can be modulated via regular exercise, with the aim to modulate plaque formation in atherosclerosis.

Carbonate fluxes by coccolithophore species between NW Africa and the Caribbean: Implications for the biological carbon pump.

Coccolithophores are among the most important calcifying pelagic organisms. To assess how coccolithophore species with different coccolith-carbonate mass and distinct ecological resilience to ocean warming will influence the "rain ratio" and the "biological carbon pump", 1 yr of species-specific coccolith-carbonate export fluxes were quantified using sediment traps moored at four sites between NW Africa and the Caribbean (i.e., CB-20°N/21°W, at 1214 m; M1-12°N/23°W, at 1150 m; M2-14°N/37°W, at 1235 m; M4-12°N/49°W, at 1130 m). Highest coccolith-CaCO3 fluxes at the westernmost site M4, where the nutricline is deepest along the tropical North Atlantic, were dominated by deep-dwelling small-sized coccolith species Florisphaera profunda and Gladiolithus flabellatus. Total coccolith-CaCO3 fluxes of 371 mg m-2 yr-1 at M4 were followed by 165 mg m-2 yr-1 at the north-easternmost CB, 130 mg m-2 yr-1 at M1, and 114 mg m-2 yr-1 at M2 in between. Coccoliths accounted for nearly half of the total carbonate flux at M4 (45%), much higher compared to 23% at M2 and 15% at M1 and CB. At site M4, highest ratios of coccolith-CaCO3 to particulate organic carbon fluxes and weak correlations between the carbonate of deep-dwelling species and particulate organic carbon suggest that increasing productivity in the lower photic zone in response to ocean warming might enhance the rain ratio and reduce the coccolith-ballasting efficiency. The resulting weakened biological carbon pump could, however, be counterbalanced by increasing frequency of Saharan dust outbreaks across the tropical Atlantic, providing mineral ballast as well as nutrients to fuel fast-blooming and ballast-efficient coccolithophore species.

Remote ischemic conditioning enhances heart and brain antioxidant defense.

BACKGROUND: Ischemia-reperfusion injury contributes to morbidity after revascularization procedures. Along with early reperfusion, tissue conditioning by alternating intervals of brief ischemia-reperfusion episodes is considered the best approach to limit tissue damage. Remote ischemic conditioning is conducted remotely, in tissues other than those under ischemia. Despite this, remote ischemic conditioning protection mechanisms are poorly understood, which can lead to misapplication. OBJECTIVES: To assess whether remote ischemic conditioning works in the heart and brain through enhancement of cells' antioxidant defenses and whether the response is sustained or temporary. METHODS: Twenty-one male Wistar rats were assigned to three groups (n = 7): SHAM: same procedure as the other groups, but no remote ischemic conditioning was carried out. RIC 10: heart and brain were harvested 10 minutes after the remote ischemic conditioning protocol. RIC 60: heart and brain were harvested 60 minutes after the remote ischemic conditioning protocol. The remote ischemic conditioning protocol consisted of 3 cycles of 5 min left hindlimb ischemia followed by 5 min left hindlimb perfusion, lasting 30 min in total. Heart and brain samples were used to measure the tissue antioxidant capacity. RESULTS: Remote ischemic conditioning increased heart and brain antioxidant capacity after 10 minutes (0.746 ± 0.160/0.801 ± 0.227 mM/L) when compared to SHAM (0.523 ± 0.078/0.404 ± 0.124 mM/L). No enhancement of heart or brain antioxidant capacity was detected 60 minutes after remote ischemic conditioning (0.551 ± 0.073/0.455 ± 0.107 mM/L). CONCLUSIONS: Remote ischemic conditioning temporarily enhances heart and brain antioxidant defenses in male Wistar rats.

CONTEXTO: A lesão de isquemia e reperfusão contribui para a morbidade após procedimentos de revascularização. Juntamente com a reperfusão precoce, o condicionamento tecidual através de breves episódios de isquemia e reperfusão é considerado a melhor abordagem para limitar o dano tecidual. Apesar disso, os mecanismos do condicionamento isquêmico remoto são pouco compreendidos, o que pode levar a uma aplicação incorreta. OBJETIVOS: Avaliar se o condicionamento isquêmico remoto funciona no coração e no cérebro através do aprimoramento da defesa antioxidante das células e se é uma resposta sustentada ou temporária. MÉTODOS: Vinte e um ratos Wistar foram divididos em três grupos (n = 7): SHAM, no qual não foi realizado condicionamento isquêmico; RIC 10, no qual 10 minutos após o protocolo de condicionamento isquêmico, foi realizada a coleta dos órgãos; e RIC 60, no qual 60 minutos após o protocolo de condicionamento isquêmico, foi realizada a coleta dos órgãos. O protocolo de condicionamento isquêmico remoto consistiu em três ciclos de 5 minutos de isquemia, seguidos de 5 minutos de perfusão no membro posterior esquerdo, com duração total de 30 minutos. Amostras foram usadas para medir a capacidade antioxidante do tecido. RESULTADOS: O condicionamento isquêmico remoto aumentou a capacidade antioxidante do coração e do cérebro após 10 minutos (0,746 ± 0,160/0,801 ± 0,227 mM/L) quando comparado ao SHAM (0,523 ± 0,078/0,404 ± 0,124 mM/L) . Sessenta minutos após o condicionamento isquêmico remoto, não foi detectado aumento da capacidade antioxidante do coração ou do cérebro (0,551 ± 0,073/0,455 ± 0,107 mM/L). CONCLUSÕES: O condicionamento isquêmico remoto melhora temporariamente as defesas antioxidantes do coração e do cérebro em ratos Wistar.

An Ocean-Colour Time Series for Use in Climate Studies: The Experience of the Ocean-Colour Climate Change Initiative (OC-CCI).

Ocean colour is recognised as an Essential Climate Variable (ECV) by the Global Climate Observing System (GCOS); and spectrally-resolved water-leaving radiances (or remote-sensing reflectances) in the visible domain, and chlorophyll-a concentration are identified as required ECV products. Time series of the products at the global scale and at high spatial resolution, derived from ocean-colour data, are key to studying the dynamics of phytoplankton at seasonal and inter-annual scales; their role in marine biogeochemistry; the global carbon cycle; the modulation of how phytoplankton distribute solar-induced heat in the upper layers of the ocean; and the response of the marine ecosystem to climate variability and change. However, generating a long time series of these products from ocean-colour data is not a trivial task: algorithms that are best suited for climate studies have to be selected from a number that are available for atmospheric correction of the satellite signal and for retrieval of chlorophyll-a concentration; since satellites have a finite life span, data from multiple sensors have to be merged to create a single time series, and any uncorrected inter-sensor biases could introduce artefacts in the series, e.g., different sensors monitor radiances at different wavebands such that producing a consistent time series of reflectances is not straightforward. Another requirement is that the products have to be validated against in situ observations. Furthermore, the uncertainties in the products have to be quantified, ideally on a pixel-by-pixel basis, to facilitate applications and interpretations that are consistent with the quality of the data. This paper outlines an approach that was adopted for generating an ocean-colour time series for climate studies, using data from the MERIS (MEdium spectral Resolution Imaging Spectrometer) sensor of the European Space Agency; the SeaWiFS (Sea-viewing Wide-Field-of-view Sensor) and MODIS-Aqua (Moderate-resolution Imaging Spectroradiometer-Aqua) sensors from the National Aeronautics and Space Administration (USA); and VIIRS (Visible and Infrared Imaging Radiometer Suite) from the National Oceanic and Atmospheric Administration (USA). The time series now covers the period from late 1997 to end of 2018. To ensure that the products meet, as well as possible, the requirements of the user community, marine-ecosystem modellers, and remote-sensing scientists were consulted at the outset on their immediate and longer-term requirements as well as on their expectations of ocean-colour data for use in climate research. Taking the user requirements into account, a series of objective criteria were established, against which available algorithms for processing ocean-colour data were evaluated and ranked. The algorithms that performed best with respect to the climate user requirements were selected to process data from the satellite sensors. Remote-sensing reflectance data from MODIS-Aqua, MERIS, and VIIRS were band-shifted to match the wavebands of SeaWiFS. Overlapping data were used to correct for mean biases between sensors at every pixel. The remote-sensing reflectance data derived from the sensors were merged, and the selected in-water algorithm was applied to the merged data to generate maps of chlorophyll concentration, inherent optical properties at SeaWiFS wavelengths, and the diffuse attenuation coefficient at 490 nm. The merged products were validated against in situ observations. The uncertainties established on the basis of comparisons with in situ data were combined with an optical classification of the remote-sensing reflectance data using a fuzzy-logic approach, and were used to generate uncertainties (root mean square difference and bias) for each product at each pixel.

Can Smartphones Be Used to Perform Video-Assisted Microanastomosis? An Experimental Study.

BACKGROUND: Smartphone cameras are continuously improving. The present study aimed to evaluate the possibility of using smartphones' magnification system to perform microanastomosis in rats. METHODS: Fifteen rats were randomly divided into 3 groups, according to the magnification system used: Microscope, iPhone 7 smartphone, and Galaxy S7 smartphone. In the microscope group, a DFVasconcelos microsurgery microscope was used. In both smartphone groups, the magnifications systems were connected to a 55-inch television through the mirror function. Animals in both groups underwent femoral artery anastomosis in the right forepaw and femoral nerve neurorrhaphy in the left hindleg. The body weight, arterial and nerve caliber, and anastomosis time and patency were immediately analyzed. RESULTS: No significant differences were observed between the groups regarding body weight, arterial, or nerve caliber. The smartphones did not provide a sufficient quality of image for an adequate identification of the arterial walls. Therefore, neither arterial anastomosis nor neurorrhaphy could be completed, even after 3 hours of surgery. The first steps toward anastomosis or raffia were performed with difficulty. CONCLUSION: The current video resolution and lack of stereoscopic image of available smartphones is not sufficient to perform video-assisted anastomosis of femoral arteries or nerves.

Remote ischemic conditioning temporarily improves antioxidant defense.

BACKGROUND: Remote ischemic conditioning (RIC) is the most promising surgical approach to mitigate ischemia and reperfusion (IR) injury. It consists in performing brief cycles of IR in tissues other than those exposed to ischemia. The underlying mechanisms of the induced protection are barely understood, so we evaluated if RIC works enhancing the antioxidant defense of the liver and kidney before IR injury. MATERIALS AND METHODS: Twenty-one Wistar rats were assigned into three groups as follows: sham, same surgical procedure as in the remaining groups was performed, but no RIC was carried out. RIC 10, RIC was performed, and no abdominal organ ischemia was induced. After 10 min of the end of the RIC protocol, the liver and kidney were harvested. RIC 60, similar procedure as performed in RIC 10, but the liver and the kidney were harvested 60 min. RIC consisted of three cycles of 5-min left hind limb ischemia followed by 5-min left hind limb perfusion, lasting 30 min in total. Samples were used to measure tissue total antioxidant capacity. RESULTS: RIC protocol increased both liver (1.064 ± 0.26 mM/L) and kidney (1.310 ± 0.17 mM/L) antioxidant capacity after 10 min when compared with sham (liver, 0.759 ± 0.10 mM/L and kidney, 1.08 ± 0.15 mM/L). Sixty minutes after the RIC protocol, no enhancement on liver (0.687 ± 0.13 mM/L) or kidney (1.09 ± 0.15 mM/L) antioxidant capacity was detected. CONCLUSIONS: RIC works through temporary and short-term enhancement of liver and kidney cells antioxidant defenses to avoid the deleterious consequences of a future IR injury.

Patient organisations' views, motivations and experiences on patient involvement in cancer research: a pilot study in Portugal.

OBJECTIVES: To characterise Portuguese cancer-related patient organisations and analyse their views, motivations and experiences on patient involvement in cancer research. DESIGN: A multistakeholder group, comprising patient representatives and researchers, codesigned a questionnaire after a literature review, online sessions and collaborative mind maps. In May 2021, a survey was conducted among representatives of Portuguese cancer-related patient organisations, focusing on four dimensions: experience in cancer research; perception of its outcomes; motivations and expectations on patient involvement in research; and organisation characteristics. PARTICIPANTS: Twenty-seven representatives from Portuguese cancer-related patient organisations responded to the questionnaire, corresponding to a 64% response rate. RESULTS: Among the surveyed organisations, 26% have participated in clinical studies. Their involvement occurred in few stages of the research process and, mostly, with low levels of engagement. They showed 'great interest' in participating in most research steps, although this is not reflected in a high perception of influence over these same steps. More than half claimed to have contributed to the increase in patient recruitment and to a better understanding of informed consent by patients involved. Ensuring that research results are more aligned with the true needs of patients is the greatest motivation. Also, our results suggest that the organisation's number of employees and its integration into a European/International network play a relevant role in patient involvement in research. CONCLUSIONS: This study provides the first in-depth characterisation of Portuguese cancer-related patient organisations and their views, motivations and experiences on patient involvement in cancer research. Most importantly, this study revealed that most of these organisations show great interest in being involved in different R&D stages to ensure that research results are aligned with patients' needs. Their motivation should be turned into greater and more meaningful involvement in practice, so that the cancer community can benefit from the outcomes of truly patient-centred research.

Ontogeny of classical and operant learning behaviors in zebrafish.

The performance of developing zebrafish in both classical and operant conditioning assays was tested with a particular focus on the emergence of these learning behaviors during development. Strategically positioned visual cues paired with electroshocks were used in two fully automated assays to investigate both learning paradigms. These allow the evaluation of the behavioral performance of zebrafish continuously throughout development, from larva to adult. We found that learning improves throughout development, starts reliably around week 3, and reaches adult performance levels at week 6. Adult fish quickly learned to perform perfectly, and the expression of the learned behavior is manifestly controlled by vision. The memory is behaviorally expressed in adults for at least 6 h and retrievable for at least 12 h.

Functional organization of the yeast proteome by a yeast interactome map.

It is hoped that comprehensive mapping of protein physical interactions will facilitate insights regarding both fundamental cell biology processes and the pathology of diseases. To fulfill this hope, good solutions to 2 issues will be essential: (i) how to obtain reliable interaction data in a high-throughput setting and (ii) how to structure interaction data in a meaningful form, amenable to and valuable for further biological research. In this article, we structure an interactome in terms of predicted permanent protein complexes and predicted transient, nongeneric interactions between these complexes. The interactome is generated by means of an associated computational algorithm, from raw high-throughput affinity purification/mass spectrometric interaction data. We apply our technique to the construction of an interactome for Saccharomyces cerevisiae, showing that it yields reliability typical of low-throughput experiments from high-throughput data. We discuss biological insights raised by this interactome including, via homology, a few related to human disease.

Does the type of electrode affect the electromyoneurographic parameters in rats?1.

PURPOSE: To evaluate if the type of electrode (needle vs. surface) affects the electromyoneurography parameters in rats. METHODS: Twenty male rats were anesthetized, then compound muscle action potential were recorded using a Neuropack S1 MEB- 9400©. All animals were submitted to two electroneuromyography analysis: first with surface electrode and then by needle electrode. We evaluated the latency, amplitude, duration and area of the negative peak of the gastrocnemius and cranial tibial muscles. RESULTS: There were no significant differences between the groups in the mean of duration, latency, amplitude or area of the negative peak in gastrocnemius and cranial tibial muscles. CONCLUSION: The type of electrode does not affect the electroneuromyography parameters.

So Close, yet so Far: Discrepancies between Uveal and Other Melanomas. A Position Paper from UM Cure 2020.

Despite much progress in our understanding of uveal melanoma (UM) over the past decades, this rare tumour is still often misclassified. Although UM, like other melanomas, is very probably derived from melanocytes, it is drastically different from cutaneous melanoma and most other melanoma subtypes in terms of epidemiology, aetiology, biology and clinical features, including an intriguing metastatic hepatotropism. UM carries distinctive prognostic chromosome alterations, somatic mutations and gene expression profiles, allowing an active tailored surveillance strategy and dedicated adjuvant clinical trials. There is no standard systemic treatment for disseminated UM at present. In contrast to cutaneous melanoma, UMs are not BRAF-mutated, thus curtailing the use of B-Raf inhibitors. Although these tumours are characterised by some immune infiltrates, immune checkpoint inhibitors are rarely effective, possibly due to a low mutation burden. UM patients across the world not only face rare cancer-related issues (e.g., specific management strategies, access to information and to expert centres), but also specific UM problems, which can be exacerbated by the common misconception that it is a subtype of cutaneous melanoma. As a European Consortium dedicated to research on UM and awareness on the disease, "UM Cure 2020" participants urge medical oncologists, pharmaceutical companies, and regulatory agencies to acknowledge UM as a melanoma with specific issues, in order to accelerate the development of new therapies for patients.

Satellite Ocean Colour: Current Status and Future Perspective.

Spectrally resolved water-leaving radiances (ocean colour) and inferred chlorophyll concentration are key to studying phytoplankton dynamics at seasonal and interannual scales, for a better understanding of the role of phytoplankton in marine biogeochemistry; the global carbon cycle; and the response of marine ecosystems to climate variability, change and feedback processes. Ocean colour data also have a critical role in operational observation systems monitoring coastal eutrophication, harmful algal blooms, and sediment plumes. The contiguous ocean-colour record reached 21 years in 2018; however, it is comprised of a number of one-off missions such that creating a consistent time-series of ocean-colour data requires merging of the individual sensors (including MERIS, Aqua-MODIS, SeaWiFS, VIIRS, and OLCI) with differing sensor characteristics, without introducing artefacts. By contrast, the next decade will see consistent observations from operational ocean colour series with sensors of similar design and with a replacement strategy. Also, by 2029 the record will start to be of sufficient duration to discriminate climate change impacts from natural variability, at least in some regions. This paper describes the current status and future prospects in the field of ocean colour focusing on large to medium resolution observations of oceans and coastal seas. It reviews the user requirements in terms of products and uncertainty characteristics and then describes features of current and future satellite ocean-colour sensors, both operational and innovative. The key role of in situ validation and calibration is highlighted as are ground segments that process the data received from the ocean-colour sensors and deliver analysis-ready products to end-users. Example applications of the ocean-colour data are presented, focusing on the climate data record and operational applications including water quality and assimilation into numerical models. Current capacity building and training activities pertinent to ocean colour are described and finally a summary of future perspectives is provided.

Yeast Protein Interactome topology provides framework for coordinated-functionality.

The architecture of the network of protein-protein physical interactions in Saccharomyces cerevisiae is exposed through the combination of two complementary theoretical network measures, betweenness centrality and 'Q-modularity'. The yeast interactome is characterized by well-defined topological modules connected via a small number of inter-module protein interactions. Should such topological inter-module connections turn out to constitute a form of functional coordination between the modules, we speculate that this coordination is occurring typically in a pairwise fashion, rather than by way of high-degree hub proteins responsible for coordinating multiple modules. The unique non-hub-centric hierarchical organization of the interactome is not reproduced by gene duplication-and-divergence stochastic growth models that disregard global selective pressures.

Influence of oophorectomy on glycemia and lipidogram.

PURPOSE: To verify the influence of oophorectomy on lipidogram and glycemia. METHODS: Fifty six female rats were divided into the following 7 groups (n = 8): group 1 - sham group, group 2 - oophorectomy 30 days, group 3 - oophorectomy 35 days, group 4 - oophorectomy 40 days, group 5 - oophorectomy 45 days, group 6 - oophorectomy 70 days, group 7 - oophorectomy 55 days. Animals were following by number of days according the group. Was evaluated the serum levels of glucose and lipid profile. RESULTS: The oophorectomized rats presented higher glycemia. Groups 3, 4, 6 and 7 had a higher glycemia and LDL levels (except for group 6) and groups 6 and 7 had lowest levels of HDL. Group 7 had highest level of VLDL than oophorectomy groups. There was no difference in triglycerides levels. CONCLUSION: Oophorectomy was related to dyslipidemia and insulin resistance, mainly after 50th days.

Morphometric analysis of rat femoral vessels under a video magnification system.

The right femoral vessels of 80 rats were identified and dissected. External lengths and diameters of femoral arteries and femoral veins were measured using either a microscope or a video magnification system. Findings were correlated to animals' weights. Mean length was 14.33 mm for both femoral arteries and femoral veins, mean diameter of arteries was 0.65 mm and diameter of veins was 0.81 mm. In our sample, rats' body weights were only correlated with the diameter of their femoral veins.

Os vasos femorais de 80 ratos foram identificados e dissecados. O comprimento e o diâmetro externo da artéria e da veia femoral foram mensurados com o auxílio de um microscópio e um sistema de magnificação por vídeo. Esses parâmetros foram correlacionados com o peso do animal. O comprimento de ambos os vasos femorais foi de 14,33 mm, e a média do diâmetro das artérias foi de 0,65 mm, e das veias, de 0,81 mm. Na nossa amostra, o peso dos animais se correlacionou apenas com o diâmetro da veia femoral.

Continuous versus interrupted suture technique in microvascular anastomosis in rats.

PURPOSE: To compare the continuous and interrupted suture technique on femoral artery on rats after vessel repair and 14 days after. METHODS: Twenty rats were operated randomly divided into two group matched according to the suture technique used: interrupted or continuous. We performed a femoral anastomosis on the right femoral artery. We analyzed weight, arterial caliber, anastomosis time and patency after vessel repair and 14 days after. RESULTS: There was no significant difference between groups in the weight (p=0.64), diameter of the femoral artery (p=0.95) and patency (p=1.00). The time spent in the anastomosis was 451 seconds in the continuous group and 718 seconds in the interrupted group, presenting significant difference (p<0.01). CONCLUSION: The continuous suture technique shows a similar patency rates than interrupted technique, however with a shorter time to perform the anastomosis.

Perconditioning combined with postconditioning on kidney ischemia and reperfusion.

PURPOSE:: To evaluate if combination of perconditioning and postconditioning provides improved renal protection compared to perconditioning alone in a model of renal reperfusion injury. METHODS:: Thirty rats were assigned into 6 groups: normality; sham; ischemia and reperfusion; postconditioning; perconditioning; perconditioning + postconditioning. Animals were subjected to right nephrectomy and left renal ischemia for 30 minutes. Postconditioning consisted of 3 cycles of 5 min renal perfusion followed by 5 min of renal ischemia after major ischemic period. Perconditioning consisted of 3 cycles of 5 min hindlimb ischemia followed by 5 min of hindlimb perfusion contemporaneously to renal major ischemic period. After 24 hours, kidney was harvested and blood collected to measure urea and creatinine. RESULTS:: Perconditioning obtained better values for creatinine and urea level than only postconditioning (p<0.01); performing both techniques contemporaneously had no increased results (p>0.05). Regarding tissue structure, perconditioning was the only technique to protect the glomerulus and tubules (p<0.05), while postconditioning protected only the glomerulus (p<0.05). Combination of both techniques shows no effect on glomerulus or tubules (p>0.05). CONCLUSIONS:: Perconditioning had promising results on ischemia and reperfusion induced kidney injury, enhanced kidney function and protected glomerulus and tubules. There was no additive protection when postconditioning and perconditioning were combined.

The Universal Non-Neuronal Nature of Parkinson's Disease: A Theory.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders, yet the etiology of the majority of its cases remains unknown. In this manuscript, relevant published evidence is interpreted and integrated into a comprehensive hypothesis on the nature, origin, and inter-cellular mode of propagation of sporadic PD. We propose to characterize sporadic PD as a pathological deviation in the global gene expression program of a cell: the PD expression-state, or PD-state for short. A universal cell-generic state, the PD-state deviation would be particularly damaging in a neuronal context, ultimately leading to neuron death and the ensuing observed clinical signs. We review why ageing associated accumulated damage caused by oxidative stress in mitochondria could be the trigger for a primordial cell to shift to the PD-state. We propose that hematopoietic cells could be the first to acquire the PD-state, at hematopoiesis, from the disruption in reactive oxygen species homeostasis that arises with age in the hematopoietic stem-cell niche. We argue that cellular ageing is nevertheless unlikely to explain the shift to the PD-state of all the subsequently affected cells in a patient, thus indicating the existence of a distinct mechanism of cellular propagation of the PD-state. We highlight recently published findings on the inter-cellular exchange of mitochondrial DNA and the ability of mitochondrial DNA to modulate the cellular global gene expression state and propose this could form the basis for the inter-cellular transmission of the PD-state.

First evaluation of neustonic microplastics in Black Sea waters.

The Black Sea has a high risk of plastic pollution given the high river discharge of several industrialized countries into this semi-enclosed sea. Here, for the first time, the occurrence and distribution of microplastics are reported for the Black Sea. Microplastics were assessed from zooplankton samples taken during two cruises along the south eastern coast of the Black Sea in the November of 2014 and February of 2015. In each cruise neuston samples were collected at 12 stations using a WP2 net with 200 µm mesh. Microplastics (0.2-5 mm) were found in 92% of the samples. The primary shapes were fibres (49.4%) followed by plastic films (30.6%) and fragments (20%), and no micro beads were found. Average microplastic concentration in November (1.2 ± 1.1 × 10(3) par. m(-3)) was higher than in February (0.6 ± 0.55 × 10(3) par. m(-3)). Reduced concentrations in February were possibly caused by increased mixing. The highest concentrations of microplastics were observed in offshore stations during November sampling. The heterogeneous spatial distribution (0.2 × 10(3)-3.3 × 10(3) par. m(-3) for all samples) and accumulation in some stations could be associated to transport and retention mechanisms linked with wind and the dynamics of the rim current, as well by different sources of plastic. There were no statistically significant differences in MP concentration between sampling stations and sampling periods (t-test, p < 0.05).The relatively high microplastic concentrations suggest that Black Sea is a hotspot for microplastic pollution and there is an urgency to understand their origins, transportation and effects on marine life.