Hochschulbibliothekszentrum des Landes Nordrhein-Westfalen (hbz)
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Spatial–Temporal Variation of Grain Magnesium, Calcium and Their Response to Phosphorus Nutrition in Sweet Corn
No full textSweet corn (Zea mays L. saccharata) is gaining global popularity as a staple crop and a vegetable due to its high nutritional value. However, information on grain magnesium (Mg) and calcium (Ca) status and their response to phosphorus (P) fertilization in sweet corn is still insufficient. In the current study, we combined the genotype evaluation and P gradient experiments to investigate how P supply influences the spatio-temporal variation of grain mineral nutrition (Mg and Ca) and their bioavailabilities in sweet corn. Increasing P decreased grain Ca by 16.7%, from 0.18 to 0.15 g kg−1, but increased phytic acid phosphorus (PAP) concentration by 7.4%. Optimal P levels increased grain Mg concentration by 14.7%, from 1.36 to a peak of 1.56 g kg−1; however, excessive P reduced it by 3.8% to 1.50 g kg−1. Spatially, optimal P increased the grain Mg concentration across all cob positions and in the germ, with the largest variation observed at the upside position (Coefficient of variation (cv) = 11.88%). Conversely, high P decreased Mg concentration in middle-cob grains and the germ. High P also reduced Ca in the upper/middle-cob grain and in both germ and endosperm. P consistently increased grain PAP but reduced Mg and Ca bioavailability across all growth stages, all grain fractions, and the middle/bottom cob positions. Notably, PAP showed the largest variation at the late growth stage in bottom cob grains (CV = 8.75%). Mg and Ca bioavailabilities exhibited significant variations, primarily in upper grains during the early filling stage, with CVs reaching 14.5% and 43.23%, respectively. Temporally, early grain growth stage was more sensitive to P-induced changes in Mg, Ca and their bioavailabilities, while later growth stage was more responsive to grain PAP alterations. These findings suggest that reducing P input can be advantageous for achieving high Mg and Ca biofortified sweet corn grain
In Vitro Effects of Rumex confertus Extracts on Cell Viability and Molecular Pathways in MCF-7 Breast Cancer Cells
No full textRumex confertus (RC), a plant known for its traditional medicinal uses, has shown potential anticancer properties, particularly due to its rich phenolic content. Despite its promising bioactivity, its effects on breast cancer cells remain underexplored. Here, we investigated the cytotoxic effects of RC extracts on MCF-7 breast cancer cells, employing various solvents for extraction. This study revealed that the hexane extract significantly reduced the cell viability, with an IC50 of 9.40 µg/mL after 96 h. The gene expression analysis indicated a substantial modulation of transcriptional networks, including the upregulation of pluripotency-related genes and the downregulation of differentiation markers. The findings suggest that the RC extract may induce a shift towards a less differentiated, stem-like state in cancer cells, potentially enhancing malignancy resistance. This study underscores the potential of RC as a candidate for breast cancer treatment, and a further investigation into its therapeutic applications is suggested
Evaluating Therapeutic Efficacy of Intravesical Xenogeneic Urothelial Cell Treatment Alone and in Combination with Chemotherapy or Immune Checkpoint Inhibition in a Mouse Non-Muscle-Invasive Bladder Cancer Model
No full textBACKGROUND/OBJECTIVES:
Bladder cancer is a malignant disease that causes more than 199,922 deaths a year globally, in which ~75% of all newly diagnosed cases are non-muscle-invasive bladder cancer (NMIBC). Despite a number of treatments available, most NMIBC patients with high-grade tumors eventually recur. To add a novel therapy to complement the deficits of the current treatments, this study assesses the antitumor activity and mechanisms of action of intravesical xenogeneic urothelial cell (XUC) treatment as monotherapy and in combination with either chemotherapy or immune checkpoint inhibition (ICI).
METHODS:
The orthotopic NMIBC graft tumor-bearing mice were randomly assigned into different treatment groups, receiving either intravesical XUCs, gemcitabine, anti-programmed death-ligand 1 (PD-L1) antibodies alone or in combination with gemcitabine or anti-PD-1 antibodies. The tumor responses, survival, and immune reactions were analyzed.
RESULTS:
Intravesical XUC treatment exhibited significantly more antitumor activity to delay tumor progression than the control group and a similar effect to chemotherapy and ICI. In addition, there were significantly higher effects in the combined groups than single treatments. Immune tumor microenvironment and immune cell proliferation, cytotoxicity, and cytokine secretion were also activated by XUC treatment. Moreover, the combined groups have the highest effects.
CONCLUSIONS:
In vivo and ex vivo studies showed increased antitumor efficacy and immune responses by intravesical XUC treatment in single and combined treatments, suggesting a potential utility of this xenogeneic cell immunotherapeutic agent. Intravesical XUC treatment has the potential to address the substantial unmet need in NMIBC therapy as a bladder-sparing treatment option for NMIBC
Comparison of Carbapenem vs. Amikacin Antimicrobial Therapy for Pediatric Acute Pyelonephritis Caused by Extended-Spectrum Β-Lactamase-Positive Enterobacteriaceae
No full textOBJECTIVES:
Acute pyelonephritis (APN) caused by extended-spectrum β-lactamase (ESBL)-positive Enterobacteriaceae poses a growing therapeutic challenge in children, as carbapenems remain the mainstay of treatment even when susceptibility to alternative agents such as amikacin is demonstrated. However, the widespread and inappropriate use of carbapenems can lead to carbapenem resistance. The aim of this study was to compare the clinical efficacy of amikacin and carbapenems in the management of pediatric acute pyelonephritis caused by ESBL-positive Enterobacteriaceae.
METHODS: We analyzed cases of pediatric acute pyelonephritis caused by ESBL-positive Enterobacteriaceae that were treated with either carbapenems or amikacin over a two-year period. This study compared microbiological cure, clinical improvement, and recurrence rates across the amikacin and carbapenem treatment groups.
RESULTS: Fifty-five patients were evaluated. The median age of the patients was 3 years (range, 0.1–13 years). The causative agents were E. coli in 43 cases (78.2%) and Klebsiella spp. in 12 cases (21.8%). All were susceptible to both carbapenem and amikacin in vitro. Twenty patients (36.3%) received a carbapenem and thirty-five (63.7%) received amikacin. Twenty-four (43.6%) had an underlying urological disease. No difference was observed between the groups in terms of microbiological cure, clinical improvement, or recurrence rates. CONCLUSIONS: Amikacin may be a potential alternative to carbapenems for treating pediatric ESBL-positive APN when in vitro susceptibility is confirmed
Sustainable Hydrogels for Medical Applications: Biotechnological Innovations Supporting One Health
No full textThe One Health paradigm—recognizing the interconnected health of humans, animals, and the environment—promotes the development of sustainable technologies that enhance human health while minimizing ecological impact. In this context, bio-based hydrogels have emerged as a promising class of biomaterials for advanced medical applications. Produced through biotechnological methods such as genetic engineering and microbial fermentation, these hydrogels are composed of renewable and biocompatible materials, including recombinant collagen, elastin, silk fibroin, bacterial cellulose, xanthan gum, and hyaluronic acid. Their high water content, structural tunability, and biodegradability make them ideal candidates for various biomedical applications such as wound healing, tissue regeneration, and the design of extracellular matrix (ECM)-mimicking scaffolds. By offering controlled mechanical properties, biocompatibility, and the potential for minimally invasive administration, sustainable hydrogels represent a strategic innovation for regenerative medicine and therapeutic interventions. This review discusses the characteristics and medical applications of these hydrogels, highlighting their role in advancing sustainable healthcare solutions within the One Health framework
Wave erosion, frontal bending, and calving at Ross Ice Shelf
No full text<jats:p>Abstract. Ice shelf calving constitutes roughly half of the total mass loss from the Antarctic ice sheet. Although much attention is paid to calving of giant tabular icebergs, these events are relatively rare. Here, we investigate the role of frontal melting and stresses at the ice shelf front in driving bending and calving on the scale of ∼100 m, perpendicular to the ice edge. We focus in particular on how buoyant underwater “feet” that protrude beyond the above-water ice cliff may cause tensile stresses at the base of the ice. Indirect and anecdotal observations of such feet at the Ross Ice Shelf front suggest that the resulting bending may be widespread and can trigger calving. We consider satellite observations together with an elastic beam model and a parameterization of wave erosion to better understand the dynamics at the ice shelf front. Our results suggest that on average frontal ablation rather consistently accounts for 20±5 m yr−1 of ice loss at Ross Ice Shelf, likely mostly due to wave erosion and smaller-scale, (100 m), foot-induced calving. This constitutes only ∼2 % of the total frontal mass loss (since near-front ice velocities are ∼1000 m yr−1). Observational evidence suggests that sporadic larger events can skew this rate (we document one foot-induced calving event of size ∼1 km). Stresses from foot-induced bending are likely not sufficient to initiate crevassing but rather act to propagate existing crevasses. In addition, our results support recent findings by Buck (2024) that additional bending moments, likely due to temperature gradients in the ice, may play a role in driving frontal deflections. The highly variable environment, irregularity of pre-existing crevasse spacing, and complex rheology of the ice continue to pose challenges in better constraining the drivers behind the observed deformations and resulting calving rates.
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BDNF levels in serum and CSF are associated with clinicoradiological characteristics of aggressive disease in MS patients
No full text<jats:title>Abstract</jats:title>
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<jats:title>Background</jats:title>
<jats:p>BDNF has increasingly gained attention as a key molecule controlling remyelination with a prominent role in neuroplasticity and neuroprotection. Still, it remains unclear how BDNF relates to clinicoradiological characteristics particularly at the early stage of the disease where precise prognosis for the further MS course is crucial.</jats:p>
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<jats:title>Methods</jats:title>
<jats:p>BDNF, NfL and GFAP concentrations in serum and CSF were assessed in 106 treatment naïve patients with MS (pwMS) as well as 73 patients with other inflammatory/non-inflammatory neurological or somatoform disorders using a single molecule array HD-1 analyser. PwMS were evaluated for highly active profiles by applying the aggressive disease course criteria proposed by ECTRIMS. Serum/CSF values were logarithmically transformed and compared across groups using one-way ANOVA, while correlations were calculated using Pearson’s correlations. ROC analysis and AUC comparisons for diagnostic performance of the three biomarkers were computed in an explorative analysis.</jats:p>
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<jats:title>Results</jats:title>
<jats:p>Serum BDNF (sBDNF) concentrations were higher in treatment naïve pwMS with disease onset after the age of 40 years (<jats:italic>p</jats:italic> = 0.029), in pwMS with ≥2 gadolinium-enhancing lesions (<jats:italic>p</jats:italic> = 0.009) and with motor, cerebellar, cognitive or sphincter symptoms at onset (<jats:italic>p</jats:italic> = 0.036). BDNF correlated positively with NfL (<jats:italic>r</jats:italic> = 0.198, <jats:italic>p</jats:italic> = 0.014) and GFAP (<jats:italic>r</jats:italic> = 0.253, <jats:italic>p</jats:italic> = 0.002) in serum, but not in CSF. Neurological patients with an acute inflammatory relapse showed significantly higher sBDNF levels (<jats:italic>p</jats:italic> = 0.03) compared to somatoform controls, while patients without acute relapse did not differ from somatoform controls (<jats:italic>p</jats:italic> = 0.4). Better diagnostic performance was found for sBDNF than sNfL and sGFAP in differentiating between patients with vs. without 2 or more gadolinium-enhancing lesions (<jats:italic>p</jats:italic> &lt; 0.05) and for sBDNF as compared to sNfL for separating patients with disease onset after vs. before age of 40 years.</jats:p>
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<jats:title>Conclusion</jats:title>
<jats:p>In pwMS, BDNF serum levels differ depending on disease-related characteristics, suggesting that not only inflammatory activity but also remyelination capacities may vary with disease severity. BDNF is increased when other biomarkers of neuroaxonal damage and neurodegeneration, such as NfL and GFAP, are elevated, possibly as a compensatory mechanism, and reflect possibly further pathophysiological aspects in MS beyond NfL and GFAP, probably including an apoptotic role for BDNF in neuroinflammation.</jats:p>
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How long does carbon stay in a near-pristine central Amazon forest? An empirical estimate with radiocarbon
No full text<jats:p>Abstract. Amazon forests play a significant role in the global C cycle by assimilating large amounts of CO2 through photosynthesis and by storing C largely as biomass and soil organic matter. To evaluate the net budget of C in the Amazon, we must also consider the amplitude and timing of losses of C back to the atmosphere through respiration and biomass burning. One useful timescale metric that integrates such information in terrestrial ecosystems is the transit time of C, defined as the time elapsed between C entering and leaving the ecosystem; the transit time is equivalent to the age of C exiting the ecosystem, which occurs mostly through respiration. We estimated the mean transit time of C for a central Amazon forest based on the C age during ecosystem respiration (ER), taking advantage of the large variations in CO2 in the atmosphere below the forest canopy to estimate the radiocarbon signature of mean ER (Δ14CER) using Keeling and Miller–Tans mixing models. We collected air samples to evaluate changes in the isotopic signature of the main ER sources by estimating the δ13CER. We collected air samples in vertical profiles in October 2019 and December 2021 at the Amazon Tall Tower Observatory (ATTO) in the central Amazon. Air samples were collected in a diel cycle from two heights below the canopy (4 and 24 m above ground level (a.g.l.)). Afternoon above-canopy samples (79 and 321 m a.g.l.) were collected as the background. For the campaign of October 2019, the mean Δ14CER ranged from 24 ‰ to 41 ‰ with both Keeling and Miller–Tans methods. In December 2021, mean Δ14CER ranged from 53 ‰ to 102 ‰. The δ13CER showed a smaller variation, being −27.8 ‰ ± 0.3 ‰ in October 2019 and −29.0 ‰ ± 0.5 ‰ in December 2021. The Δ14CER estimates were compared with the record of atmospheric radiocarbon from the bomb period, providing estimates of mean transit time of 6 ± 2 years for 2019 and 18 ± 4 years for 2021. In contrast to steady-state carbon balance models that predict constant mean transit times, these results suggest an important level of variation in mean transit times. We discuss these results in the context of previous model-based estimates of mean transit time for tropical forests and the Amazon region. In addition, we discuss previous studies that indicate that approximately 70 % of assimilated carbon is respired as autotrophic respiration in the central Amazon. Our results suggest that newly fixed carbon in this terra firme tropical forest is respired within 1 to 2 decades, implying that only a fraction of assimilated C can act as a sink for decades or longer.
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Preface: ICFM9 – River Basin Disaster Resilience and Sustainability by All
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Assessing the impacts of simulated ocean alkalinity enhancement on viability and growth of nearshore species of phytoplankton
No full text<jats:p>Abstract. Over the past 250 years, atmospheric CO2 concentrations have risen steadily from 277 to 405 ppm, driving global climate change. In response, new tools are being developed to remove carbon from the atmosphere using negative emission technologies (NETs), in addition to reducing anthropogenic emissions. One proposed NET is ocean alkalinity enhancement (OAE), in which artificially raising the alkalinity favours formation of bicarbonate from CO2, leading to a decrease in the partial pressure of CO2 in the water. Subsequent invasion of atmospheric CO2 results in net sequestration of atmospheric carbon. The aim of this study was to investigate the impact of simulated OAE, through the alteration of pH, on phytoplankton representative of the spring and fall blooms in nearshore, temperate waters. The potential impacts of OAE were assessed through (1) an analysis of prior studies investigating the effects of elevated pH on phytoplankton growth rates and (2) an experimental assessment of the potential impact of short-term (10 min) and long-term (8 d) elevation of pH on the viability and subsequent growth rates of two representative nearshore species of phytoplankton. Viability was assessed with a modified serial dilution culture–most probable number assay. Chlorophyll a fluorescence was used to test for changes in photosynthetic competence and apparent growth rates. There were no significant impacts on the viability or growth rates of the diatom Thalassiosira pseudonana and the prymnesiophyte Diacronema lutheri (formerly Pavlova lutheri) with short-term (10 min) exposure to elevated pH. However, there was a significant decrease in growth rates with long-term (8 d) exposure to elevated pH. Short-term exposure is anticipated to more closely mirror the natural systems in which land-based OAE will be implemented because of system flushing and dilution. The analysis of prior studies indicates wide variability in the growth response to elevated pH within and between taxonomic groups, with about 50 % of species expected to not be impacted by the pH increase anticipated from unequilibrated mineral-based OAE. To the extent that the growth responses reflect (largely unreported) parallel reductions in dissolved inorganic carbon (DIC) availability, the susceptibility may be reduced for OAE in which CO2 ingassing is not prevented.
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