18F-FDG PET/CT anatomic and metabolic guidance in CT-guided lung biopsies.

PURPOSE: To evaluate the role of Fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT as a metabolic guide in increasing the accuracy, diagnostic yield and safety of CT-guided percutaneous needle lung biopsy (PNB). METHODS AND MATERIALS: Retrospective analysis of 340 consecutive patients with suspicious lung nodules, masses or extensive disease that underwent lung biopsy over a 3-year period. Patients were divided into three groups; those that had PET/CT prior to the biopsy, those that had PET-CT following the biopsy and those who did not undergo PET-CT. Correlation was made with the histopathological result. RESULTS: 353 PNBs were performed (median lesion size 30 mm, 7-120 mm) with overall diagnostic rate of 83.9 % (95.8 % malignant). Biopsy success rate was 88.8 % with PET-CT pre-PNB, versus 78.9 % of 175 PNB without PET-CT upfront (p < 0.01 Fisher exact test). Correct targeting to PET-CT-maximum activity area (MAA) was present in 87.1 %. Biopsy success rate was 88.8 % for PNBs targeting the PET-CT-MAA region and only 52.8 % for PNBs not targeting the PET-CT-MAA (p < 0.0001). PET-CT pre-PNB had higher rates of PET-CT-MAA targeting compared to PET-CT post PNB (91.0 % v 80.0 %, p = 0.01). The availability of PET-CT before the PNB lead to significantly increased biopsy success rates in patients with a mass (OR:7.01p = 0.004), compared to a nodule (p = 0.498) or multiple nodules (p = 0.163). Patients with a PET-CT pre-PNB underwent fewer PNB passes (mean 2.6 v 3.1, p < 0.0001 Mann Whitney U). Serious complications were less common in PET-CT pre-PNB group (4.5 % v 10.9 %, p < 0.05). Pre-PNB PET-CT performance improvement applied to all 3 radiologists and was greatest for masses and infiltrative abnormalities. CONCLUSION: Metabolic information provided by 18F-FDG PET/CT and PNB localisation to the PET-CT maximum activity region is associated with higher diagnostic biopsy rates especially in masses and appears to account for improved performance, less needle passes and complications when available pre-biopsy.

Beyond taxonomic diversity patterns - investigating how α and ß components of macrophyte functional diversity respond to environmental gradients in lotic ecosystems of Greece.

In addition to quantifying the taxonomic diversity of aquatic communities, understanding the patterns of alpha functional diversity (α-diversity) and exploring changes in functional dissimilarity (ß-diversity) can improve our understanding on how ecosystems respond to environmental changes. In this study, we quantified functional alpha (α) and beta (ß) diversity of macrophytic assemblages from river sites in Greece and then, examined relationships with water quality parameters and hydromorphological factors. We assigned 6 traits (Ellenberg nutrients indicator, Ellenberg light indicator, growth form, leaf size, leaf type, fruit size) to a total of 36 hydrophyte species and calculated three indices of functional diversity (functional richness, functional dispersion and functional evenness). We also estimated the total ß-functional diversity and its' main components, turnover and nestedness. To assess the effects of water quality (including physical and chemical variables) we used Generalized Additive Models (GAM) for alpha functional diversity indices and Generalized Dissimilarity Models (GDM) for beta functional diversity. We performed Kruskal-Wallis tests and permutational multivariate analysis of variance (PERMANOVA) to search for significant variations of α- and ß-diversity among the hydromorphological factors. Our results showed that macrophyte growth form and light preference were important trait characteristics that explained a large share of the total variance of functional composition. We also found relatively low taxonomic and functional richness, whereas taxonomic and functional dissimilarity were mostly attributed to species turnover, which expresses the changes in taxonomic and functional composition. We found significant relationships between functional dispersion and functional evenness with pH and oxygen saturation, whereas functional dissimilarity was driven only by geographic distance, although the GDM explained a small portion of the total variance. Functional richness, dispersion and evenness were significantly higher at systems with fine substrates and deep waters with low or high flow compared to systems with coarser substrates and riffle habitats. We also found significant variation in functional dissimilarity among the hydromorphological factors, although much of the total variance remained unexplained. Overall, our study highlights the importance of considering the functional diversity of aquatic plant assemblages within the frame of freshwater monitoring and conservation plans.

Assessing temporal variability of lake turbidity and trophic state of European lakes using open data repositories.

Water turbidity is one of the more important water quality parameters that is strictly linked with the productivity of the lake and is commonly used as an indicator of the trophic state. However, limited field data availability across wide geographic gradients may hinder the conduction of large scale longitudinal studies. In this study, time series of lake turbidity and trophic state index (TSI) between 2002 and 2012 were obtained from the Copernicus Lake Water products to create a large longitudinal dataset of lake variables for 22 European lakes. The dataset was combined with estimates of nutrient concentrations and surface water temperature obtained from the Hydrological Predictions for the Environment (HYPE) and ERA5-Land data repositories, that were used as environmental predictors. Hence, the validity of the lake water quality parameters was tested by a) exploring their spatial and temporal variability and b) identifying associations with the environmental predictors. For this purpose, seasonal Mann-Kendall tests were applied to find significant inter-annual trends of turbidity and TSI for each lake, and generalized additive models (GAMs) were employed to identify the main parameters that shape their temporal dynamics. Although we did not find significant inter-annual changes, our findings highlighted the strong influence of seasonality and surface water temperature in defining the temporal variability patterns in most of the lakes. In addition, the importance of nutrients varied among lakes as several lakes exhibited narrow nutrient gradients reflecting relatively stable nutrient conditions during the examined period. Other lake intrinsic factors, such as local climate and biotic interactions, are important drivers of shaping turbidity and nutrient dynamics. This study highlighted the usefulness of combining lake data from large repositories in conducting large scale spatial studies as a valuable asset for future lake research and management purposes.

Photoacclimation impacts the molecular features of photosystem supercomplexes in the centric diatom Thalassiosira pseudonana.

In diatoms, light-harvesting processes take place in a specific group of proteins, called fucoxanthin chlorophyll a/c proteins (FCP). This group includes many members and represents the major characteristic of the diatom photosynthetic apparatus, with specific pigments bound (chlorophyll c, fucoxanthin, diadino- and diatoxanthin besides chlorophyll a). In thylakoids, FCP and photosystems (PS) form multimeric supercomplexes. In this study, we compared the biochemical properties of PS supercomplexes isolated from Thalassiosira pseudonana cells grown under low light or high light conditions, respectively. High light acclimation changed the molecular features of the PS and their ratio in thylakoids. In PSII, no obvious changes in polypeptide composition were observed, whereas for PSI changes in one specific group of FCP proteins were detected. As reported before, the amount of xanthophyll cycle pigments and their de-epoxidation ratio was increased in PSI under HL. In PSII, however, no additional xanthophyll cycle pigments occurred, but the de-epoxidation ratio was increased as well. This comparison suggests how mechanisms of photoprotection might take place within and in the proximity of the PS, which gives new insights into the capacity of diatoms to adapt to different conditions and in different environments.

Trends of lake temperature, mixing depth and ice cover thickness of European lakes during the last four decades.

Lakes are particularly vulnerable ecosystems to global warming. Surface temperature of most lakes in the world has significantly increased. Here, we analysed time-series of water temperature, mixing-depth, and ice depth of 51 European lakes over the last four decades. We used data of surface temperature, total layer water temperature, mix-layer temperature, mix-layer depth, and ice cover depth obtained from the ERA5-Land reanalysis dataset. Our main objectives were a) to identify significant changes of the examined variables that have occurred from 1981 to 2019 and b) to assess the variability of changes in relation with geographical and lake morphological gradients. To this end, time series analysis was conducted using generalized additive models (GAMs). In addition, we quantified the magnitude of change by estimating the Sen's slopes for each variable and then we examined the variability of these slopes to geographical and lake morphological parameters using GAMs. Our results confirmed that water temperature parameters (surface, total-layer and mix-layer temperature) have significantly increased for all lakes during the last four decades. We also found significant changes of the mixing depth for 14 lakes. In addition, the lake ice depth has significantly decreased in all fifteen lakes of the subarctic climate region. Finally, we showed that the Sen's slopes depend on the geographic coordinates and the elevation of the lakes, whereas lake morphometry (e.g. depth) has a smaller effect on the magnitude of changes. These findings hint that lake ecosystems of Europe have substantially changed over the last forty years and urge the need to take precautionary measures to prevent future implications for the freshwater biota.

Wnt4, Wnt6 and ß-catenin expression in human placental tissue - is there a link with first trimester miscarriage? Results from a pilot study.

BACKGROUND: Demystifying the events around early pregnancy is challenging. A wide network of mediators and signaling cascades orchestrate the processes of implantation and trophoblast proliferation. Dysregulation of these pathways could be implicated in early pregnancy loss. There is accumulating evidence around the role of Wnt pathway in implantation and early pregnancy. The purpose of this study was to explore alterations in the expression of Wnt4, Wnt6 and ß-catenin in placental tissue obtained from human first trimester euploid miscarriages versus normally developing early pregnancies. METHODS: The study group consisted of first trimester miscarriages (early embryonic demises and incomplete miscarriages) and the control group of social terminations of pregnancy (TOPs). The placental mRNA expression of Wnt4, Wnt6 and ß-catenin was studied using reverse transcription PCR and real time PCR. Only euploid conceptions were included in the analysis. RESULTS: Wnt4 expression was significantly increased in placental tissue from first trimester miscarriages versus controls (p = 0.003). No significant difference was documented in the expression of Wnt6 (p = 0.286) and ß-catenin (p = 0.793). There was a 5.1fold increase in Wnt4 expression for early embryonic demises versus TOPs and a 7.6fold increase for incomplete miscarriages versus TOPs - no significant difference between the two subgroups of miscarriage (p = 0.533). CONCLUSIONS: This is, to our knowledge, the first study demonstrating significant alteration of Wnt4 expression in human placental tissue, from failed early pregnancies compared to normal controls. Undoubtedly, a more profound study is needed to confirm these preliminary findings and explore Wnt mediators as potential targets for strategies to predict and prevent miscarriage.

Dual-energy CT in pulmonary vascular disease.

Dual-energy CT (DECT) imaging is a technique that extends the capabilities of CT beyond that of established densitometric evaluations. CT pulmonary angiography (CTPA) performed with dual-energy technique benefits from both the availability of low kVp CT data and also the concurrent ability to quantify iodine enhancement in the lung parenchyma. Parenchymal enhancement, presented as pulmonary perfused blood volume maps, may be considered as a surrogate of pulmonary perfusion. These distinct capabilities have led to new opportunities in the evaluation of pulmonary vascular diseases. Dual-energy CTPA offers the potential for improvements in pulmonary emboli detection, diagnostic confidence, and most notably severity stratification. Furthermore, the appreciated insights of pulmonary vascular physiology conferred by DECT have resulted in increased use for the assessment of pulmonary hypertension, with particular utility in the subset of patients with chronic thromboembolic pulmonary hypertension. With the increasing availability of dual energy-capable CT systems, dual energy CTPA is becoming a standard-of-care protocol for CTPA acquisition in acute PE. Furthermore, qualitative and quantitative pulmonary vascular DECT data heralds promise for the technique as a "one-stop shop" for diagnosis and surveillance assessment in patients with pulmonary hypertension. This review explores the current application, clinical value, and limitations of DECT imaging in acute and chronic pulmonary vascular conditions. It should be noted that certain manufacturers and investigators prefer alternative terms, such as spectral or multi-energy CT imaging. In this review, the term dual energy is utilised, although readers can consider these terms synonymous for purposes of the principles explained.

The Evolving Landscape of Lung Cancer Surgical Resection: An Update for Radiologists With Focus on Key Chest CT Findings.

Evolution of the multimodality management of early lung cancer, including progress in surgical techniques, has introduced the possibility of resection for lung cancer cases that historically were considered unresectable (e.g., select cases of T4 disease and oligometastatic disease). However, the TNM classification does not uniformly correlate with lung cancer operability and resectability. Radiologic evaluation is therefore critical in identifying patients' suitability to undergo lung cancer resection and in guiding the selection of a surgical approach from among a range of such approaches, including wedge resection, segmentectomy, lobectomy, bilobectomy, and pneumonectomy. The radiologist must understand the available surgical options, along with their advantages and disadvantages, and provide a report that includes critical information on tumor size, location, and extension and anatomic relations that may influence the surgical technique. Preoperative CT findings may also help predict expected postoperative lung function and the associated impact on the postoperative course of the patient. This article reviews the role of chest CT in the preoperative evaluation of lung cancer, focusing on the key CT findings that help direct surgical decision making in the context of an expanding range of patients who may be considered candidates for resection.

Responses of different facets of aquatic plant diversity along environmental gradients in Mediterranean streams: Results from rivers of Greece.

Aquatic and riparian plants play a crucial role in the functioning of riverine ecosystems. Hence, analyzing multiple facets of plant diversity could be extremely useful for assessing the ecological integrity of lotic ecosystems. The main objective of this study was to investigate the response of multiple facets of aquatic plant diversity, such as species richness, taxonomic distinctness and compositional dissimilarity, to environmental factors (i.e. nutrient pollution and hydromorphological alteration) in 72 stream reaches of mainland Greece. We employed Generalized Additive Models to identify the variables with the highest influence and examine the response of species richness and taxonomic distinctness to environmental gradients. The relationship between compositional dissimilarity and the environment was examined with Generalized Dissimilarity Modelling. Our results supported our hypothesis that human disturbances play a considerable role in shaping macrophyte assemblages. In particular, phosphates and hydromorphological modification were significant predictors of species richness, whereas taxonomic distinctness was unaffected by indicators of anthropogenic stress but it was influenced mostly by elevation, water temperature and pH. Concerning the compositional dissimilarity, geographic distance, elevation, temperature and total inorganic nitrogen were the most important environmental parameters. Our findings suggest that human stressors, such as hydromorphological modification and nutrient enrichment, affect the plant species richness at stream reach scale, but when considering community composition or taxonomic distinctness, environmental factors associated with the natural variability (e.g. elevation, temperature and geographic distance) are of higher importance. Overall, our results emphasize the advantage of examining multiple aspects of diversity when designing conservation schemes and management plans for riparian areas.

Chest CT severity score and radiological patterns as predictors of disease severity, ICU admission, and viral positivity in COVID-19 patients.

BACKGROUND: Chest computed tomography (CT) is a useful tool for the diagnosis of coronavirus disease-2019 (COVID-19), although its exact value for predicting critical illness remains unclear. This study evaluated the efficacy of chest CT to predict disease progression, pulmonary complications, and viral positivity duration. METHODS: A single-center cohort study was conducted by consecutively including hospitalized patients with confirmed COVID-19. The chest CT patterns were described and a total severity score was calculated. The predictive accuracy of the severity score was evaluated using the receiver operating characteristic analysis, while a Cox proportional hazards regression model was implemented to identify the radiological features that are linked to prolonged duration of viral positivity. RESULTS: Overall, 42 patients were included with 10 of them requiring intensive care unit admission. The most common lesions were ground glass opacities (92.9%), consolidation (66.7%), and crazy-paving patterns (61.9%). The total severity score significantly correlated with inflammatory and respiratory distress markers, as well as with admission CURB-65 and PSI/PORT scores. It was estimated to predict critical illness with a sensitivity and specificity of 75% and 70%, respectively. Time-to-event analysis indicated that patients without ground-glass opacities presented significantly shorter median viral positivity (16 vs. 27 days). CONCLUSIONS: Chest CT severity score positively correlates with markers of COVID-19 severity and presents promising efficacy in predicting critical illness. It is suggested that ground-glass opacities are linked to prolonged viral positivity. Further studies should confirm the efficacy of the severity score and elucidate the long-term pulmonary effects of COVID-19.

Delineating the relative contribution of climate related variables to chlorophyll-a and phytoplankton biomass in lakes using the ERA5-Land climate reanalysis data.

Understanding the climatic drivers of eutrophication is critical for lake management under the prism of the global change. Yet the complex interplay between climatic variables and lake processes makes prediction of phytoplankton biomass a rather difficult task. Quantifying the relative influence of climate-related variables on the regulation of phytoplankton biomass requires modelling approaches that use extensive field measurements paired with accurate meteorological observations. In this study we used climate and lake related variables obtained from the ERA5-Land reanalysis dataset combined with a large dataset of in-situ measurements of chlorophyll-a and phytoplankton biomass from 50 water bodies to develop models of phytoplankton related responses as functions of the climate reanalysis data. We used chlorophyll-a and phytoplankton biomass as response metrics of phytoplankton growth and we employed two different modelling techniques, boosted regression trees (BRT) and generalized additive models for location scale and shape (GAMLSS). According to our results, the fitted models had a relatively high explanatory power and predictive performance. Boosted regression trees had a high pseudo R2 with the type of the lake, the total layer temperature, and the mix-layer depth being the three predictors with the higher relative influence. The best GAMLSS model retained mix-layer depth, mix-layer temperature, total layer temperature, total runoff and 10-m wind speed as significant predictors (p<0.001). Regarding the phytoplankton biomass both modelling approaches had less explanatory power than those for chlorophyll-a. Concerning the predictive performance of the models both the BRT and GAMLSS models for chlorophyll-a outperformed those for phytoplankton biomass. Overall, we consider these findings promising for future limnological studies as they bring forth new perspectives in modelling ecosystem responses to a wide range of climate and lake variables. As a concluding remark, climate reanalysis can be an extremely useful asset for lake research and management.

Radiological, epidemiological and clinical patterns of pulmonary viral infections.

Respiratory viruses are the most common causes of acute respiratory infections. However, identification of the underlying viral pathogen may not always be easy. Clinical presentations of respiratory viral infections usually overlap and may mimic those of diseases caused by bacteria. However, certain imaging morphologic patterns may suggest a particular viral pathogen as the cause of the infection. Although definitive diagnosis cannot be made on the basis of clinical or imaging features alone, the use of a combination of clinical and radiographic findings can substantially improve the accuracy of diagnosis. The purpose of this review is to present the clinical, epidemiological and radiological patterns of lower respiratory tract viral pathogens providing a comprehensive approach for their diagnosis and identification in hospitals and community outbreaks.

A pictorial review of the utility of CEUS in thoracic biopsies.

Lung cancer is one of the commonest malignancies worldwide and necessitates both early and personalised treatment. A key requirement is histological sampling with immunohistochemistry obtained usually from percutaneous biopsy. Conventionally thoracic biopsies are performed using CT guidance, but more recently, there has been development of physician led ultrasound biopsy for pleural lesions. Contrast-enhanced ultrasound (CEUS) has been increasingly used in interventional procedures and is able to offer benefits for thoracic biopsies including improving lesional visualisation and characterisation, targeting viable tissue and avoiding critical vascular structures as well as evaluating for the presence of post-procedural complications. This educational review aims to benefits of the role of CEUS in thoracic biopsies.

Impact of nutrients and water level changes on submerged macrophytes along a temperature gradient: A pan-European mesocosm experiment.

Submerged macrophytes are of key importance for the structure and functioning of shallow lakes and can be decisive for maintaining them in a clear water state. The ongoing climate change affects the macrophytes through changes in temperature and precipitation, causing variations in nutrient load, water level and light availability. To investigate how these factors jointly determine macrophyte dominance and growth, we conducted a highly standardized pan-European experiment involving the installation of mesocosms in lakes. The experimental design consisted of mesotrophic and eutrophic nutrient conditions at 1 m (shallow) and 2 m (deep) depth along a latitudinal temperature gradient with average water temperatures ranging from 14.9 to 23.9°C (Sweden to Greece) and a natural drop in water levels in the warmest countries (Greece and Turkey). We determined percent plant volume inhabited (PVI) of submerged macrophytes on a monthly basis for 5 months and dry weight at the end of the experiment. Over the temperature gradient, PVI was highest in the shallow mesotrophic mesocosms followed by intermediate levels in the shallow eutrophic and deep mesotrophic mesocosms, and lowest levels in the deep eutrophic mesocosms. We identified three pathways along which water temperature likely affected PVI, exhibiting (a) a direct positive effect if light was not limiting; (b) an indirect positive effect due to an evaporation-driven water level reduction, causing a nonlinear increase in mean available light; and (c) an indirect negative effect through algal growth and, thus, high light attenuation under eutrophic conditions. We conclude that high temperatures combined with a temperature-mediated water level decrease can counterbalance the negative effects of eutrophic conditions on macrophytes by enhancing the light availability. While a water level reduction can promote macrophyte dominance, an extreme reduction will likely decrease macrophyte biomass and, consequently, their capacity to function as a carbon store and food source.

The impact of vascular endothelial growth factor single nucleotide polymorphisms in the development and severity of endometriosis: A systematic review of the literature.

OBJECTIVE: To review the impact of single nucleotide polymorphisms (SNPs) of the vascular endothelial growth factor (VEGF) gene in the development and severity of endometriosis. SEARCH STRATEGY: We searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL and Google Scholar databases for published studies in the field. SELECTION CRITERIA: We included prospective and retrospective observational studies. DATA COLLECTION AND ANALYSIS: Data extraction was performed using a modified data form that was based in Cochrane`s data collection form for intervention reviews. MAIN RESULTS: Twenty studies were included that investigated the frequency of the various alleles of the -460C/T, +405G/C, +936C/T, -2578A/C and -1154G/A SNPs. The Hardy-Weinberg equilibrium revealed that the different genotypes were comparable among patients with endometriosis and control women, as well as among patients with mild and severe forms of the disease. No differences were observed in the expression of the various alleles in the majority of cases. Ethnical variations were observed; however, the results should be regarded as inconclusive due to the small amount of available data. CONCLUSIONS: The results of our meta-analysis suggest that the investigated single nucleotide polymorphisms are unlikely to significantly contribute to the development and severity of endometriosis.

The Effect of TISSEEL® on Colorectal Anastomosis Healing Process in a Diabetic Animal Experimental Model.

BACKGROUND/AIM: Diabetes mellitus is an established risk factor of colorectal anastomosis failure. The purpose of the present study was to evaluate the effect of TISSEEL® in anastomotic healing. MATERIALS AND METHODS: Forty male, Sprague-Dawley rats were used. Diabetes was induced in half of them by intraperitoneal injection of Streptozotocin, 60 mg/kg. One week after the injection, animals were operated and a 1 cm segment was removed and an end-to-end hand sewn anastomosis was performed. TISSEEL® was applied in each group (diabetic, non-diabetic) following randomization. RESULTS: The pathology analysis revealed improved tissue remodeling in the TISSEEL® group, both for the normoglycemic and the diabetic group. Specifically, the extent of inflammation was decreased (p<0.001), whereas fibroblast and collagen formation were improved (p=0.040 and p=0.008). Neovascularization was also improved (p=0.047). CONCLUSION: Application of TISSEEL® on colorectal anastomoses improves healing in rats that suffer from severe hyperglycemia.