Tracing the early development of harmful algal blooms with the aid of Lagrangian coherent structures

Several theories have been proposed to explain the development of harmful algal blooms (HABs) produced by the toxic dinoflagellate \emph{Karenia brevis} on the West Florida Shelf. However, because the early stages of HAB development are usually not detected, these theories have been so far very difficult to verify. In this paper we employ simulated \emph{Lagrangian coherent structures} (LCSs) to trace the early location of a HAB in late 2004 before it was transported to an area where it could be detected by satellite imagery, and then we make use of a population dynamics model to infer the factors that may have led to its development. The LCSs, which are computed based on a surface flow description provided by an ocean circulation model, delineate past and future histories of boundaries of passively advected fluid domains. The population dynamics model determines nitrogen in two components, nutrients and phytoplankton, which are assumed to be passively advected by the simulated surface currents. Two nearshore nutrient sources are identified for the HAB whose evolution is found to be strongly tied to the simulated LCSs. While one nutrient source can be associated with a coastal upwelling event, the other is seen to be produced by river runoff, which provides support to a theory of HAB development that considers nutrient loading into coastal waters produced by human activities as a critical element. Our results show that the use of simulated LCSs and a population dynamics model can greatly enhance our understanding of the early stages of the development of HABs.Comment: Submitted to JGR-Ocean

Patterns of COVID-19-related headache: A cross-sectional study

Background: Headache is the most common COVID-19-related neurological symptom. We investigated the characteristics of COVID-19-related headache and their relationship with clinical severity in Kirs , ehir Province, Turkey. Methods: This cross-sectional study prospectively enrolled 226 COVID-19-positive patients who developed headache during acute infection. Demographic data, headache characteristics, and infection symptoms were recorded. The clinical severity of COVID-19 was documented in each participant. Result: New-onset COVID-19-related headaches lasting 4 days were reported in 164 patients (72.5 %); these were mostly bilaterally or localized to the forehead (58.4 %), pulsating (42.5 %), moderate to severe intensity (30.1 %), with a partial response to paracetamol (23.5 %). The other 62 patients (27.4 %) reported headaches before COVID-19. Their COVID-related headaches were fiery type (p = 0.025), of very severe intensity (p = 0.008), had a holocranial distribution (p = 0.004), and were less response to paracetamol (p = 0.003); the headaches were significantly more frequent after COVID-19 than before COVID-19. Older age, high body mass index, and low education level were significantly higher in the severe group (all p < 0.001). Female sex (p = 0.019) and being a healthcare worker (p < 0.001) were significantly more frequent in mild cases. Conclusions: Bilateral, prolonged, moderate to severe headaches that were analgesic resistant are more frequent in patients with COVID-19 infection. Further study should examine whether the headache characteristics distinguish COVID-19-related headaches from other types, particularly in asymptomatic subjects

Evaluation of the biocompatibility of experimentally manufactured portland cement: an animal study

Objectives: The purpose of this study was to evaluate the biocompatibility of MTA and the experimentally manufactured portland cement (EMPC). Study design: Twenty one Sprague Dawley (SD) rats were allocated to testing of three groups. Group I and Group II included ProRoot MTA and the EMPC. The materials were mixed with distilled water and placed in polyethylene tubes. The tubes were implanted subcutaneously in the dorsal region of the animals. Group III served as control; the implanted polyethylene tubes remained empty. At 7, 14, and 28 days after the implantation, the animals were sacrificed and the implants were removed with the surrounding tissues. The specimens were prepared for histological examination to evaluate the inflammatory response. Results: No significant difference was found between tissue reactions against the tested materials (p>0.05). Also, control group showed similar results(p>0.05). Conclusions: Results suggest that the EMPC has the potential to be used in clinical conditions in which ProRoot MTA is indicated. MTA and the EMPC show comparable biocompatibility when evaluated in vivo. Although the results are supportive for the EMPC, more studies are required before the safe clinical use of the EMPC

A paradox from a neurotransmitter: the opposite effects of substance P and its physiological fragments SP (1-7) and SP (9-11) on the proliferation of human breast cancer cells and the migration capabilities of HUVEC cells

OBJECTIVE: Substance P (SP) is a neurotransmitter peptide, and it is known to play a major role in neurogenic inflammation, inducing local inflammatory responses, cancer, and angiogenesis. It has been previously demonstrated that SP possesses a wide range of pharmacological effects including induced cancer cell proliferation and triggered angiogenic response of tumors. However, there is no published work regarding the proliferative effects of its physiological fragments [N-terminal fragment SP (1-7) and C-terminal fragment SP (9-11)] not only on cancer cells but also on human umbilical vein endothelial cells (HUVECs). MATERIALS AND METHODS: Cells were treated with different doses of fragments and the cytotoxic effects on the proliferation of MDA-MB-231 cells were determined via MTT kit (Promega, Madison, WI, USA) and Cellular DNA Fragmentation Elisa Kit (Roche). Changes both in the pro-angiogenic and anti-angiogenic factor levels in media were evaluated by; Human VEGF ELISA kit (Thermo-Scientific, Waltham, MA, USA), Human Matrix Metallo-proteinases-9 Elisa kit (Legend Max), and Human Thrombospondin-1 Elisa kit (R&D Systems) for VEGF, MMP-9, and Thrombospondin-1 respectively. To determine the changes in the migration capabilities of HUVECs, a wound healing test was performed. RESULTS: According to our results, the fragments exhibit different effects not only on the proliferation of cancer cells and the release of pro/anti-angiogenic factors from the cells but also on the migration capabilities of HUVECs. CONCLUSIONS: This is the first report showing that the SP fragments could behave differently from the main peptide itself

The prophylactic efficacy of Anatolian propolis in individuals at high risk of COVID-19

OBJECTIVE: No prophylactic treatment is available for individuals at high risk of developing COVID-19. This study, which was conducted between December 25, 2020, and January 25, 2021, is one of the first clinical studies to evaluate the efficacy of Anatolian propolis supplement against COVID-19. The aim was to obtain evidence on the prophylactic use of Anatolian propolis in individuals at high risk of developing COVID-19. SUBJECTS AND METHODS: This volunteer-based study was conducted in two centers. The study involved 209 healthcare professionals (physicians, nurses, medical secretaries) from Emergency Medicine Department of Medical Faculty of Ataturk University and Emergency Medicine Department of Rize Recep Tayyip Erdogan University. 204 participants meeting the study criteria were divided into two groups as experimental group and control group. The experimental group received 20 drops of BEE’O UP (BEE&YOU) 30% Propolis drops twice a day during a follow-up period of 1 month. The control group received no supplement but was followed up. The participants showing symptoms during the study and all the participants at the end the study were subjected to PCR testing. RESULTS: The evaluation of the results of PCR testing at the end of the study has shown that 14 participants from the control group and only 2 participants from the experimental group, who received Anatolian propolis supplement, were reported as positive cases. CONCLUSIONS: It has been found that a statistically significant protection was induced against COVID-19 infection in 98% of the experimental group, who received Anatolian propolis, compared to the control group

Plasma biomarkers of brain injury in COVID-19 patients with neurological symptoms

Objective: Neurological symptoms (NS) were often reported in COVID-19 infection. We examined the plasma levels of glial fibrillary acidic protein (GFAP) and S100B together, as brain injury biomarkers, in relation to persistent NS in a cohort of patients with COVID-19 during the acute phase of the disease.Methods: A total of 20 healthy controls and 58 patients with confirmed COVID-19 were enrolled in this prospective study. Serum GFAP and S100B levels were measured by using enzymle linked immunoassay method from blood samples.Results: Serum GFAP levels were found to be significantly higher in the severe group than in the controls (p = 0.007). However, serum S100B levels were similar between control and disease groups (p > 0.05). No significant results for GFAP and S100B were obtained between the disease groups depending on whether the sampling time was below or above 5 days (p > 0.05). We did not find a correlation between serum GFAP and S100B levels and the presence of NS (p > 0.05). However, serum S100B levels were slightly higher in patients with multiple NS than in those with a single symptom (p = 0.044).Conclusions: Elevated GFAP was associated with disease severity but not with NS in COVID-19 patients. Whereas, high serum S100B was associated with the multipl NS in these patients. Our data suggest that GFAP and S100B may be of limited value currently in order to represent the neuronal damage, though serving a basis for the future work

Neurological symptoms and neuronal damage markers in acute COVID-19: Is there a correlation? A pilot study

A wide spectrum of neurological symptoms (NS) has been described in patients with COVID-19. We examined the plasma levels of neuron-specific enolase (NSE) and neurofilament light chain (NFL) together, as neuronal damage markers, and their relationships with clinical severity in patients with NS at acute COVID-19. A total of 20 healthy controls and 59 patients with confirmed COVID-19 were enrolled in this pilot prospective study. Serum NSE and NFL levels were measured by using the enzyme-linked immunoassay method from serum samples. Serum NSE levels were found to be significantly higher in the severe group than in the nonsevere group (p = 0.034). However, serum NFL levels were similar between the control and disease groups (p > 0.05). For the mild group, serum NFL levels were significantly higher in patients with the sampling time >= 5 days than in those with the sampling time 0.05). Increased serum NSE levels were associated with disease severity regardless of accompanied NS in patients with acute COVID-19 infection. However, serum NFL levels may have a role at the subacute phase of COVID-19

Variability in regional background aerosols within the Mediterranean

The main objective of this study is the identification of major factors controlling levels and chemical composition of aerosols in the regional background (RB) along the Mediterranean Basin (MB). To this end, data on PM levels and speciation from Montseny (MSY, NE Spain), Finokalia (FKL, Southern Greece) and Erdemli (ERL, Southern Turkey) for the period 2001 to 2008 are evaluated. Important differences on PM levels and composition are evident when comparing the Western and Eastern MBs. The results manifest W-E and N-S PM&lt;sub&gt;10&lt;/sub&gt; and PM&lt;sub&gt;2.5&lt;/sub&gt; gradients along the MB, attributed to the higher frequency and intensity of African dust outbreaks in the EMB, while for PM&lt;sub&gt;1&lt;/sub&gt; very similar levels are encountered. &lt;br&gt;&lt;br&gt; PM in the EMB is characterized by higher levels of crustal material and sulphate as compared to WMB (and central European sites), however, RB nitrate and OC + EC levels are relatively constant across the Mediterranean and lower than other European sites. Marked seasonal trends are evidenced for PM levels, nitrate (WMB), ammonium and sulphate. Also relatively higher levels of V and Ni (WMB) are measured in the Mediterranean basin, probably as a consequence of high emissions from fuel-oil combustion (power generation, industrial and shipping emissions). &lt;br&gt;&lt;br&gt; Enhanced sulphate levels in EMB compared to WMB were measured. The high levels of sulphate in the EMB may deplete the available gas-phase NH&lt;sub&gt;3&lt;/sub&gt; so that little ammonium nitrate can form due to the low NH&lt;sub&gt;3&lt;/sub&gt; levels. &lt;br&gt;&lt;br&gt; This study illustrates the existence of three very important features within the Mediterranean that need to be accounted for when modeling climate effects of aerosols in the area, namely: a) the increasing gradient of dust from WMB to EMB; b) the change of hygroscopic behavior of mineral aerosols (dust) via nitration and sulfation; and c) the abundance of highly hygroscopic aerosols during high insolation (low cloud formation) periods

Variability in regional background aerosols within the Mediterranean

The main objective of this study is the identification of major factors controlling levels and chemical composition of aerosols in the regional background (RB) along the Mediterranean Basin (MB). To this end, data on PM levels and speciation from Montseny (MSY, NE Spain), Finokalia (FKL, Southern Greece) and Erdemli (ERL, Southern Turkey) for the period 2001 to 2008 are evaluated. Important differences on PM levels and composition are evident when comparing the Western and Eastern MBs. The results manifest W-E and N-S PM(10) and PM(2.5) gradients along the MB, attributed to the higher frequency and intensity of African dust outbreaks in the EMB, while for PM(1) very similar levels are encountered