The Arctic Ocean north of Svalbard has recently experienced large sea ice losses and the increasing prominence of Atlantic water (AW) advection. To investigate the impact of these ongoing changes on ...annual particle export, two moorings with sequential sediment traps were deployed in ice‐free and seasonally ice‐covered waters on the shelf north (NSv) and east (ESv) of Svalbard, collecting sinking particles nearly continuously from October 2017 to October 2018. Vertical export of particulate organic carbon (POC), total particulate matter (TPM), planktonic protists, chlorophyll a, and zooplankton fecal pellets were measured, and swimmers were quantified and identified. Combined with sensor data from the moorings, these time‐series measurements provided a first assessment of the factors influencing particle export in this region of the Arctic Ocean. Higher annual TPM and POC fluxes at the ice‐free NSv site were primarily driven by the advection of AW, higher grazing by large copepods, and a wind‐induced mixing event during winter. Higher diatom fluxes were observed during spring in the presence of sea ice at the ESv site. Along with sea ice cover, regional differences in AW advection and the seasonal presence of grazers played a prominent role in the biological carbon pump along the continental shelf off Svalbard.
Plain Language Summary
Recently, the area north of Svalbard has experienced the largest reduction of winter sea ice extent in the Arctic Ocean and an increasing influence of warm Atlantic water (AW) in surface waters. The consequences for the marine ecosystem remain unclear. In the present study, we investigated the fate of algal production and organic matter by measuring the amount and composition of the material sinking toward the seafloor. Using sediment traps with automatically rotating bottles, the seasonal variability in the quality and quantity of the organic matter sinking to ∼100 m was investigated at two sites with and without winter sea ice on the shelf north and east of Svalbard from 2017 to 2018. Our results suggest that the AW inflow along the shelf break induces a gradient with more zooplankton in the west and more ice in the east. More zooplankton in the west rework the organic matter through grazing, resulting in higher flux of carbon than in the east. Less zooplankton in the east potentially leaves more algal cells to sink ungrazed. As algal fluxes were higher in the presence of sea ice, a future with less sea ice may result in more reworked material sinking to the seafloor.
Key Points
Sea ice melt led to higher springtime and annual diatom fluxes at the seasonally ice‐covered site
Aside from algal fluxes, annual particle fluxes were higher at the ice‐free site
Atlantic water advection, zooplankton grazing, wind‐induced mixing, and resuspension contributed to the higher fluxes at the ice‐free site
Aim
To describe the evolution of electroencephalogram (EEG) characteristics in infants with tuberous sclerosis complex (TSC) and the relationship with neurodevelopmental outcome at 24 months.
Method
...Eighty‐three infants were enrolled in the EPISTOP trial and underwent serial EEG follow‐up until the age of 24 months (males n=45, females n=37, median age at enrolment 28d, interquartile range 14–54d). Maturation of the EEG background and epileptiform discharges were compared between the TSC1 and TSC2 variants and between preventive and conventional groups respectively.
Results
Children with TSC2 more frequently had a slower posterior dominant rhythm (PDR) at 24 months (51% vs 11%, p=0.002), a higher number of epileptiform foci (median=8 vs 4, p=0.003), and a lower fraction of EEGs without epileptiform discharges (18% vs 61%, p=0.001) at follow‐up. A slower PDR at 24 months was significantly associated with lower cognitive (median=70 vs 80, p=0.028) and motor developmental quotients (median=70 vs 79, p=0.008). A higher fraction of EEGs without epileptiform discharges was associated with a lower probability of autism spectrum disorder symptoms (odds ratio=0.092, 95% confidence interval=0.009–0.912, p=0.042) and higher cognitive (p=0.004), language (p=0.002), and motor (p=0.001) developmental quotients at 24 months.
Interpretation
TSC2 is associated with more abnormal EEG characteristics compared to TSC1, which are predictive for neurodevelopmental outcome.
2-methoxyestradiol (2-ME) is a physiological anticancer compound, metabolite of 17β-estradiol. Previously, our group evidenced that from mechanistic point of view one of anticancer mechanisms of ...action of 2-ME is specific induction and nuclear hijacking of neuronal nitric oxide synthase (nNOS), resulting in local generation of nitro-oxidative stress and finally, cancer cell death.
The current study aims to establish the substantial mechanism of generation of reactive nitrogen species by 2-ME. We further achieved to identify the specific reactive nitrogen species involved in DNA-damaging mechanism of 2-ME.
The study was performed using metastatic osteosarcoma 143B cells. We detected the release of biologically active (free) nitric oxide (•NO) with concurrent measurements of peroxynitrite (ONOO−) in real time in a single cell of 143B cell line by using •NO/ONOO− sensitive microsensors after stimulation with calcium ionophore. Detection of nitrogen dioxide (•NO2) and determination of chemical rate constants were carried out by a stopped-flow technique. The affinity of reactive nitrogen species toward the guanine base of DNA was evaluated by density functional theory calculations. Expression and localization of nuclear factor NF-kB was determined using imaging cytometry, while cell viability assay was evaluated by MTT assay.
Herein, we presented that 2-ME triggers pro-apoptotic signalling cascade by increasing cellular reactive nitrogen species overproduction – a result of enzymatic uncoupling of increased nNOS protein levels. In particular, we proved that ONOO− and •NO2 directly formed from peroxynitrous acid (ONOOH) and/or by auto-oxidation of •NO, are inducers of DNA damage in anticancer mechanism of 2-ME. Specifically, the affinity of reactive nitrogen species toward the guanine base of DNA, evaluated by density functional theory calculations, decreased in the order: ONOOH > ONOO− > •NO2 > •NO.
Therefore, we propose to consider the specific inducers of nNOS as an effective tool in the field of chemotherapy.
Carcinoma of the cervix is the most common malignancy associated with pregnancy. The frequency of cervical cancer is estimated to range from 1/1,200 to 1/10,000 pregnancies. The symptoms of cervical ...cancer are not specific and can be mistaken as frequent symptoms associated with other pathologies of pregnancy. The diagnostic procedure is similar to the one which should be proposed to unpregnant women. The treatment of cervical cancer depends on gestational age. The final treatment and further prognosis is carried out after delivery. The authors present the case of a 35-year-old woman at 34 weeks of gestation diagnosed with Stage IB cervical cancer. Treatment was delayed until fetal maturity and an elective cesarean section was performed at 36 weeks' gestation, followed by a radical hysterectomy, bilateral salpingo-oophorectomy, and a pelvic lymphadenectomy. Patient underwent adjuvant radiochemotherapy and brachytherapy. Recurrence of neoplastic process was found after one year.
Contrast-enhanced computed tomography (CECT) and positron emission tomography with 18-FDG (FDG-PET/CT) are used to identify malignant solitary pulmonary nodules. The aim of the study was to evaluate ...the accuracy of CECT and FDG-PET/CT in diagnosing the etiology of solitary pulmonary nodule (SPN). Eighty patients with newly diagnosed SPN >8 mm were enrolled. The patients were scheduled for either or both, CECT and FDG-PET/CT. The nature of SPN (malignant or benign) was determined either by its pathological examination or radiological criteria. In 71 patients, the etiology of SPN was established and these patients were included in the final analysis. The median SPN diameter in these patients was 13 mm (range 8-30 mm). Twenty-two nodules (31%) were malignant, whereas 49 nodules were benign. FDG-PET/CT was performed in 40 patients, and CECT in 39 subjects. Diagnostic accuracy of CECT was 0.58 (95% confidence interval CI 0.41-0.74). The optimal cutoff level discriminating between malignant and benign SPN was an enhancement value of 19 Hounsfield units, for which the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CECT were 100%, 37%, 32%, and 100%, respectively. Diagnostic accuracy of FDG-PET/CT reached 0.9 (95% CI 0.76-0.9). The optimal cutoff level for FDG-PET/CT was maximal standardized uptake value (SUV max) 2.1. At this point, the sensitivity, specificity, PPV, and NPV were 77%, 92%, 83%, and 89%, respectively. The diagnostic accuracy of FDG-PET/CT is higher than that of CECT. The advantage of CECT is its high sensitivity and negative predictive value.
The first metallasilsesquioxane of a divalent lanthanide, Yb{Cy
7
Si
7
O
11
(OSiMe
3
)}(THF)
2
,
1
, was synthesized and structurally characterized. The Cy
7
Si
7
O
11
(OSiMe
3
)
2−
ligands in
1
bind ...two Yb(
ii
) ions in a bridging mode. The dinuclear complex effects the two-electron reduction of azobenzene yielding the Yb(
iii
) complex {Yb(Cy
7
Si
7
O
11
(OSiMe
3
))(THF)
2
}
2
(PhNNPh),
2
, and the CO
2
reduction to CO and carbonate.
The first metallasilsesquioxane of a divalent lanthanide was synthetized and structurally characterized. The dinuclear Yb(
ii
) complex effects the two electrons reduction of azobenzene, and the selective CO
2
reduction to CO and carbonate.
The aim of this study was to evaluate platelet activation in gastric cancer patients with regard to histopathological classification and the presence of distant metastases, by using platelet ...morphological parameters: MPV, L-PLT, MPC, as well as quantitative evaluation of surface receptor expression: CD41a, CD61, CD42b, CD62P, by flow cytometry at the resting state and after TRAP activation. In gastric cancer patients higher values of MPV and LP, as well as decreased MPC values were determined. Quantitative evaluation of surface antigen expression also revealed higher number of CD41a, CD61 and CD62P molecules, as compared with the platelets in the control group. Significant decrease of CD42b molecules' number after TRAP incubation, and the increased CD41a, CD61 and CD62P expression also point to the retained reactivation capacity of platelets. Good correlation between morphological parameters and the number of CD62P molecules indicates the usefulness of routine tests in evaluation of platelet activation.
To determine the anemia prevalence and the correlation between complete blood count (CBC) analysis and renal function parameters in HIV-1-infected population.
It was a single-center study set in ...Warsaw (Poland) over a 3-year period. The study was performed in 214 adult HIV-1- infected patients (180 males and 34 females, aged from 20 to 69 years old, mean age 39.55 years, 130 on combined antiretroviral therapy, cART). Glomerular filtration rate (GFR) was estimated using the re-expressed Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas. In statistical analyses U Mann-Whitney and Spearman correlation test as logistic regression analysis was used.
25.2% of studied patients were anemic. In all of them, estimated GFR (eGFR) was positively correlated with red blood cells (RBC) and platelet (PLT) count, and negatively correlated with mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC). All these correlations were statistically significant (p < 0.001) and independent of gender and used type of eGFR formula. In logistic regression analysis, lower eGFR strongly predicted lower RBC and PLT levels (p < 0.0001; OR 0.08, 95%CI: 0.03, 0.22 and OR 0.99, 95%CI: 0.987, 0.993, respectively).
Our findings suggest a strong association between CBC and renal function in ARV-treated HIV-infected patients who fulfilled the criteria of anemia. Consequently, eGFR in all HIV-infected subjects with anemia, especially on treatment with nephrotoxic drugs and concomitant thrombocytopenia, should be monitored more frequently then standardly recommended every 3-6 months.
We describe the epidemiology and characteristics of hepatitis A among men who have sex with men (MSM)who had been hospitalised due to the infection in Warsaw, Poland, from September 2008 to September ...2009. A total of 50 men were analysed; their median age was 28 years (range: 17–43). None had travelled to hepatitis A-endemic regions during the six months before hospitalisation nor had they been vaccinated against hepatitis A. Of the 50 men, 40 had been tested before hospitalisation or on admission for the presence of anti-HIV antibodies: six were coinfected with HIV.The six HIV-positive MSM were significantly older than those who were HIV negative – median age: 37 years(range: 26–43) versus 28 years (range: 17–43); p=0.02.No difference in disease severity or the duration of hospitalisation was observed, however, between the two groups. Our study underlines the need to screen MSM for hepatitis A and to vaccinate them against hepatitis A. Given the ages of the MSM in our study,we recommend that this be carried out in Poland when the MSM are aged 20–35 years. This should apply not only to MSM with multiple casual partners but also to those in monogamous relationships.
Abstract Introduction In mammals, placenta separation at term may involve degradation of the extracellular matrix by matrix metalloproteinases (MMPs). The activity of MMPs is modulated by TIMPs. We ...hypothesized that the placentas of mares that deliver fetal membranes physiologically and those that retain fetal membranes (FMR) differ in terms of histology; mRNA expression of MMP-2 and MMP-9; protein expression of MMP-2, MMP-9, and TIMP-2; and the potential activity of both MMPs. Methods Placenta biopsies were taken from mares (n = 9; 4 FMR, 5 controls) immediately after foal expulsion. Retention was defined as failure to expel all fetal membranes within 3 h of expulsion. All mares were monitored for time of expulsion. The degree of allantochorial/endometrial adhesion was determined in FMR mares, and biopsies from all mares were histologically examined. mRNA expression, protein immunolocalization, protein amount and potential enzyme activity were determined with RT-PCR, immunohistochemistry, Western Blotting and zymography, respectively. Results FMR mares had strong to extremely strong allantochorial/endometrial adhesion, and significantly more connective tissue in the allantochorial villi than controls. The range of MMP-2 mRNA expression levels was more than 13 times greater in FMR mares than in controls. Protein content of both MMPs and TIMP-2 differed significantly between groups. The range of potential MMP-2 and MMP-9 activity was larger in FMR mares, and MMP-2 potential activity was 1.4 times higher in controls (P = 0.02). Discussion These results indicate differences in extracellular matrix remodeling in FMR mares and controls, and suggest dysregulation of MMP expression and activation in FMR mares.
PDF
