Measurement Of Activity Research Articles

Evolution of Eligibility Criteria in Inflammatory Bowel Disease Clinical Trials: A Clinical Trial Databank Analysis.

Eligibility criteria in clinical trials have been criticised for being overly restrictive without clinical justification. We aimed to investigate the types, evolution, and current status of eligibility criteria in clinical trials for inflammatory bowel diseases (IBD). We performed a clinical trial databank search on clinicaltrials.gov, and included all Phase 3 placebo-controlled randomised-controlled trials (RCTs) investigating biologics or small molecules as induction therapy for moderate-to-severe Crohn's disease (CD) and ulcerative colitis (UC). Eligibility criteria were analysed both quantitatively and qualitatively. Fifty-nine RCTs were identified between the year 2000 and 2022 (30 for CD and 29 for UC). The median (interquartile range) number of eligibility criteria was 44 (38-49), and did not significantly change over the studied time period (p=0.26). Qualitative analysis showed that common patient populations, such as older patients, therapy refractory patients, patients with comorbidities, prior malignancies, unclassified IBD type, ulcerative proctitis, stricturing and fistulizing CD, as well as patients with an ostomy, were often excluded. Heterogeneity in eligibility criteria across the different IBD clinical trials was found, such as for disease activity measurement, dosage of concomitant medication, wash-out period of advanced therapies, and laboratory tests. The median number of eligibility criteria for IBD RCTs did not significantly change over time. The eligibility criteria are however restrictive and complex, limiting the generalisability of efficacy and safety outcomes in daily practice when drugs are approved. Future research is needed to investigate the impact of broadening eligibility criteria to better encompass real-world practice.

Improving precision in physical activity measurement in developmental coordination disorder research.

Improving precision in physical activity measurement in developmental coordination disorder research.

Undernutrition-induced stunting-like phenotype in Drosophila melanogaster

Stunting resulting from undernutrition is a significant global health challenge, particularly in developing countries, yet its underlying mechanisms and consequences remain inadequately understood. This study utilizes Drosophila melanogaster as an in vivo model to investigate the molecular basis of stunting. Due to the conserved nature of signaling pathways between Drosophila and vertebrates, this organism serves as an effective model for studying growth disorders. The aim of this study was to establish a Drosophila model exhibiting a stunting-like phenotype and to elucidate the molecular mechanisms underlying this condition. The stunting phenotype was induced through dietary manipulation, involving a standard nutrient-rich diet (100%) and treatment diets with reduced concentrations of sucrose, glucose, yeast, and cornmeal at 50%, 25%, and 12.5%. Phenotypic assessments included measurements of larval body size, fecundity, survival rates, and locomotor activity, alongside molecular analyses of gene expression related to metabolism, cell proliferation, and survival, using RT-qPCR. Results demonstrated that undernutrition profoundly affected D. melanogaster, causing growth retardation, reduced larval body size, diminished fecundity, and lower survival rates, though locomotor function remained unaffected. Molecular analysis revealed a significant decrease in the expression of the totA gene and notable increases in the expression of dilp5, srl, and indy genes, with no significant changes observed in the expression of the pepck gene. These findings indicate that undernutrition induces a stunting-like phenotype, likely driven by alterations in the expression of genes associated with metabolism, cell proliferation, and survival. Overall, this study establishes D. melanogaster as a valuable in vivo model for studying stunting-like phenotypes resulting from nutritional deficiencies and provides insights into the molecular pathways involved in growth impairment.

AutoMEA: machine learning-based burst detection for multi-electrode array datasets

Neuronal activity in the highly organized networks of the central nervous system is the vital basis for various functional processes, such as perception, motor control, and cognition. Understanding interneuronal connectivity and how activity is regulated in the neuronal circuits is crucial for interpreting how the brain works. Multi-electrode arrays (MEAs) are particularly useful for studying the dynamics of neuronal network activity and their development as they allow for real-time, high-throughput measurements of neural activity. At present, the key challenge in the utilization of MEA data is the sheer complexity of the measured datasets. Available software offers semi-automated analysis for a fixed set of parameters that allow for the definition of spikes, bursts and network bursts. However, this analysis remains time-consuming, user-biased, and limited by pre-defined parameters. Here, we present autoMEA, software for machine learning-based automated burst detection in MEA datasets. We exemplify autoMEA efficacy on neuronal network activity of primary hippocampal neurons from wild-type mice monitored using 24-well multi-well MEA plates. To validate and benchmark the software, we showcase its application using wild-type neuronal networks and two different neuronal networks modeling neurodevelopmental disorders to assess network phenotype detection. Detection of network characteristics typically reported in literature, such as synchronicity and rhythmicity, could be accurately detected compared to manual analysis using the autoMEA software. Additionally, autoMEA could detect reverberations, a more complex burst dynamic present in hippocampal cultures. Furthermore, autoMEA burst detection was sufficiently sensitive to detect changes in the synchronicity and rhythmicity of networks modeling neurodevelopmental disorders as well as detecting changes in their network burst dynamics. Thus, we show that autoMEA reliably analyses neural networks measured with the multi-well MEA setup with the precision and accuracy compared to that of a human expert.

Physical Activity During Pregnancy and Preterm Birth Among Women With Gestational Diabetes.

Physical activity, as a modifiable factor, emerges as a primary intervention strategy for the prevention and management of gestational diabetes (GD). Among women with GD, the association of physical activity during pregnancy with preterm birth remains unclear. To examine the association of accelerometer-derived physical activity metrics and patterns with preterm birth among women with GD. This prospective cohort study recruited pregnant women with GD in Hangzhou, China, from August 2019 to August 2023 as part of the Westlake Precision Birth Cohort study. Statistical analysis was performed between August and November 2023. Wearable accelerometer-derived physical activity metrics and patterns. Measurements of physical activity via wearable accelerometer were performed at a median (IQR) of 25.4 (24.6-26.6) weeks' gestation. Preterm birth was determined through the examination of delivery records. Incident preterm birth was defined as the delivery of infants before completing 37 weeks of gestation. Among the 1427 women meeting the inclusion criteria, the mean (SD) age was 31.3 (3.8) years, and there were 80 cases of preterm birth. An increase in moderate-to-vigorous intensity physical activity (MVPA) and the fraction of physical activity energy expenditure derived from MVPA exhibited an inverse association with preterm birth, with an odds ratio per 30 minutes of 0.64 (95% CI, 0.42-0.98) and an odds ratio per SD of 0.69 (95% CI, 0.55-0.88). In the dose-response analysis, there was a progressive decrease in the odds of preterm birth with increasing duration of MVPA per day, reaching a plateau at approximately 74 minutes per day. Furthermore, the findings indicated that active MVPA (MVPA ≥30 minutes per day), whether it was concentrated into a few days or followed a more regular pattern, had similar beneficial association with preterm birth. In this prospective cohort study, MVPA during pregnancy exhibited an inverse association with preterm birth among women with GD. Concentrated physical activity was associated with similar benefits in reducing preterm birth risk as regular physical activity.

Spontaneous nanosized liposome formation from crude dried lecithin upon addition of glycerol

Nanosized liposomal vesicles (NLV) were successfully prepared using natural sunflower lecithin without the use of high-pressure homogenization or filtration. Upon glycerol addition to dispersions of lecithin multilamellar vesicles (MLVs), these broke down spontaneously to liposomes with diameters in the range of 100–200 nm. Static light scattering demonstrated that glycerol addition above 30% (w/w) induced the complete transformation of MLVs into NLVs. Langmuir trough compression experiments showed a two-region compressional behavior. Upon 62% (w/w) glycerol addition, the compressional modulus of the liposomes decreased from 18.5 to 8.13 mN/m. Water activity and pulse NMR measurements also showed a divergence in behavior above 30% (w/w) glycerol. Liposomes were not birefringent in water but became strongly birefringent at and above 30% (w/w) glycerol, as determined by polarized light microscopy, and lost all birefringence above 80% (w/w). This was interpreted as the induction of stress-birefringence in the phospholipid bilayers above 30% (w/w) glycerol, and a relaxation of such stress above 80% (w/w) glycerol. We hypothesize that the mixture of phospholipids in the lecithin results in an effective non-zero intrinsic curvature for the molecular mixture, which lowers the bending energy of the bilayer, allowing for an easier break-up upon mixing. Secondly, glycerol addition decreases attractive van der Waals’ interaction between lamellae in an MLV, thus weakening the multilamellar liposome walls. Glycerol also affects bilayer stability by strengthening the hydrogen bond network of water, which will affect phospholipid headgroup hydration. All these factors result in the spontaneous breakdown of MLVs into NLVs.

Exploring vacuum foam drying as an alternative to freeze-drying and spray drying for a human lipase

This article compares and explores vacuum foam-drying as an alternative drying technology to freeze-drying and spray drying for a recombinant human lipase as the model protein. Materials characteristics such as structure, surface composition and the solid-state properties of the dry materials were compared and investigated. Moreover, the technical functionality in terms of reconstitution characteristics and the lipase stability were also investigated. The stability of the lipase was evaluated through activity measurements. Sucrose and dextran D40 (40 kDa) were used as matrix former and the surfactant α-dodecyl maltoside was used as surface active additive. The study demonstrated that the drying technique greatly influenced the material structure and composition which in turn affected the reconstitution characteristics. The lipase was overrepresented at the material surface in declining order spray-dried > vacuum foam-dried > freeze-dried. The lipase activity was retained up to 10 % lipase content in solids, but at 20 % lipase a loss of activity was observed for all drying techniques. Phase separation in the solid material may be an explanation. Vacuum foam-drying shows promise as an alternative drying technique for the lipase, and potentially other proteins.

Activity measurements and calibrations for 225Ac in radioactive equilibrium with its progeny

Activity measurements and calibrations for 225Ac in radioactive equilibrium with its progeny

Purification, fibrinolytic activity and substrate binding of nattokinase from Bacillus subtilis: A rapid and sensitive detection for fibrinolytic activity of nattokinase

Nattokinase (NK, EC 3.4.21.62) is an alkaline serine protease secreted by B. subtilis, which has a strong fibrinolytic activity in vitro and in vivo. Here, we fermented NK using a B. subtilis strain and purified the protein, designed a peptide segment derived from fibrin as a substrate of NK. Based on fluorescence resonance energy transfer (FRET), we found that NK exhibits a high hydrolytic activity towards the peptide, with Km of 9.33 ± 1.28 μM, kcat of 0.20 ± 0.01 s−1, and kcat/Km of 21,436.23 s−1 M−1, demonstrating that the peptide is a substrate for NK. Furthermore, we investigated the binding of the substrate with NK by tryptophan fluorescence quenching, molecular docking and dynamics simulation. Fluorescence quenching showed that the substrate binds to NK mainly through hydrogen bonding and van der Waals forces, with dissociation constants KD of 13.73 and 21.24 μM at 25 and 35 °C, respectively. Molecular docking and dynamics analysis revealed that the substrate recognizes the active site of NK, and provides new information on the characteristics of the binding of the substrate with NK. Our study demonstrated a rapid and sensitive method for the quantitative measurement of fibrinolytic activity of NK based on the substrate, which is very reproducible and rapid with virtually complete results in approximately 20 min.

Silver-Doped Zinc Ferrite Nanoparticles: Trigger ROS-Dependent Apoptosis and Inhibit Migration in MCF-7 Breast Cancer Cells

This study describes the fabrication of nanostructured silver-doped zinc ferrite nanoparticles (AgxZn1-xFe2O4, where x = 0.0 and 0.05) using a chemical co-precipitation method. Field-emission scanning electron microscopy (FE-SEM) analysis was performed to investigate the surface characteristics and particle size of the pure and Ag-doped nanoparticles. X-ray diffraction (XRD) patterns confirmed the formation of a single-phase cubic structure for the zinc ferrite nanoparticles. The anti-cancer potential of the nanoparticles was evaluated using the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) against human breast cancer cells (MCF-7). The results showed that (AgxZn1-xFe2O4, where x = 0.05) nanoparticles with x = 0.05 exhibited significant cytotoxicity. At a concentration of 100 µg/mL, these nanoparticles reduced cell viability to 26.27%, with a calculated LC50 value (concentration lethal to 50% of cells) of 41.30 µg/mL after 24 hours of treatment. Notably, the LC50 value for (AgxZn1-xFe2O4, where x = 0.05) nanoparticles in normal L929 fibroblast cells was over four times higher compared to MCF-7 cancer cells, indicating a degree of selectivity for cancer cells. Further investigation revealed that (AgxZn1-xFe2O4, where x = 0.05) treatment significantly increased the generation of reactive oxygen species (ROS) within the cancer cells. This was confirmed by fluorescence intensity measurements, which showed a substantial increase from 1260.61 (control) to 15600 for cells treated with (AgxZn1-xFe2O4, where x = 0.05) nanoparticles. This included flow cytometry analysis of apoptosis (programmed cell death), migration assays to evaluate metastasis potential, measurement of antioxidant enzyme activity (SOD and catalase) to understand the impact on the cellular antioxidant system, indirect ELISA to detect caspase activity (a marker of apoptosis), cell cycle analysis, and finally, real-time PCR analysis to determine the mRNA expression of p53, a tumor suppressor gene. The apoptosis assay confirmed a significant increase in apoptotic cells upon treatment with (AgxZn1-xFe2O4, where x = 0.05) nanoparticles. This activity is likely mediated by the generation of ROS and subsequent oxidative stress within the cancer cells. These findings highlight the potential of these nanoparticles as a promising therapeutic strategy for cancer treatment.

Surface modification of 3D-printed polycaprolactone- human decellularized bone matrix composite scaffold by plasma for bone tissue engineering

BackgroundBone tissue engineering is a revolutionary field focused on creating viable bone substitutes using advanced materials and techniques. Utilizing 3D printing, precise and customizable bone scaffolds can be produced. A notable composite material in this domain is a composite of polycaprolactone (PCL) and human decellularized bone matrix (hDBM), which combines synthetic and natural elements for enhanced functionality. To further improve cell attachment and growth, cold plasma surface modification is employed, optimizing scaffold surfaces. These innovations collectively hold great potential for improving bone repair and regeneration outcomes. MethodsScaffold architecture was designed through CAD software, and the composite of PCL and hDBM was printed using FDM technology. Surface modification was achieved by exposing the scaffolds to Argon-Oxygen (Ar-O₂) plasma radiation for 1 and 3 minutes. Both treated and untreated scaffolds were characterized, including measurements of surface roughness, hydrophilicity, and cellular activity. ResultsAlmost all groups showed non-toxic effect on cellular behavior during cell culture. Plasma-treated scaffolds showed a significant increase in surface roughness, with roughness values (Ra) increasing from 10.45 nm (untreated) to 62.75 nm after 3 minutes of plasma exposure. Contact angle measurements decreased from approximately 66.5° in untreated scaffolds to 31.4° in those treated for 3 minutes, indicating enhanced hydrophilicity. Plasma-treated scaffolds demonstrated excellent cytocompatibility, significantly enhancing cell proliferation, osteogenic differentiation, and mineralization compared to untreated scaffolds. After 7 days, scaffolds treated for 1 and 3 minutes showed 35% and 60% increases in cell proliferation, respectively, highlighting the role of plasma treatment in creating a bioactive surface conducive to cell adhesion, growth, and improved osteogenic properties, with longer exposure times further amplifying these effects. ConclusionsThe current study demonstrates the efficacy of Ar+O₂ plasma treatment in enhancing the surface properties of PCL-hDBM scaffolds, making them more conducive to osteogenesis. This study suggests that plasma-treated PCL-hDBM scaffolds are a promising option for bone tissue engineering applications.

Perspectives of Key Stakeholders on Integrating Wearable Sensor Technology into Rehabilitation Care: A Mixed-Methods Analysis.

Rehabilitation is facing a critical practice gap: Patients seek out rehabilitation services to improve their activity in daily life, yet recent work demonstrates that rehabilitation may be having a limited impact on improving this outcome due to lack of objective data on patients' activity in daily life. Remote monitoring using wearable sensor technology is a promising solution to this address this gap. The purpose of this study was to understand patient and clinician awareness of the practice gap and preferences for integrating wearable sensor technology into rehabilitation care. This study used a mixed-methods approach consisting of surveys and 1:1 interviews with clinicians (physical and occupational therapists or assistants) employed at an outpatient rehabilitation clinic within an academic medical center and patients seeking care at this clinic. Data were analyzed using descriptive statistics and thematic analysis. Data saturation was reached from recruiting nineteen clinicians and ten patients. Both clinicians and patients recognized the importance of measuring activity outside the clinic and viewed wearable sensor technology as an objective measurement tool. Most clinicians (63%) preferred continuous (vs. intermittent) monitoring within a care episode and most patients (60%) were willing to sync their sensor data as often as instructed by their provider. To maximize integration into clinical workflows, clinicians voiced a preference for availability of sensor data in the electronic health record. Clinicians and patients value the use of wearable sensor technology to improve measurement of activity outside the clinic environment and expressed preferences for how this technology could best be integrated into routine rehabilitation care.

The protumorigenic enzyme GPAT2 inhibits arachidonic acid-triggered apoptosis in breast cancer

BackgroundCancer is a significant health challenge and the leading cause of mortality globally. Tumor cells use multiple mechanisms to acquire their distinctive capacity for uncontrolled proliferation, one of which is the evasion of apoptosis. It has been shown that in breast, colon, and liver cancer, evasion of apoptosis is associated with the overexpression of enzymes that metabolize arachidonic acid (AA) because free AA is a strong inducer of apoptosis. Glycerol−3-phosphate acyltransferase 2 (GPAT2) is a key enzyme in AA metabolism and is highly expressed in breast and colon cancer, where it promotes the development of essential tumor features.MethodsIn this work, a model of GPAT2 silencing in the human breast cancer-derived cell line MDA-MB-231 was used, and the cells were exposed to exogenous AA. The role of GPAT2 in AA-induced cell death was studied using MTT and TUNEL assays and measurements of caspase activity. The underlying molecular mechanism of cell death was assessed by qRT‒PCR.ResultsThe results showed that AA reduced cell viability only in GPAT2-silenced cells, and that this cell death was a consequence of an apoptotic process involving BNIP3 overexpression. Additionally, it was demonstrated that GPAT2 silencing triggered a compensatory mechanism by overexpressing other genes involved in AA utilization for eicosanoid biosynthesis.ConclusionsWe concluded that GPAT2 expression is necessary to prevent AA-induced apoptotic cell death in MDA-MB-231 cells and that the overexpression of other AA-metabolizing genes is not sufficient to compensate for the lack of GPAT2 and prevent apoptosis.

Minimal Clinically Important Differences With the Outcomes of the App-Based Japanese Allergic Conjunctival Diseases Quality of Life Questionnaire: Cross-Sectional Observational Study.

Assessing changes in quality of life in patients with hay fever-related allergic conjunctivitis requires validated and clinically meaningful metrics. A minimal clinically important difference (MCID) that can be applied to assess Domain II of the Japanese Allergic Conjunctival Disease Quality of Life Questionnaire (JACQLQ) in a smartphone app setting has yet to be determined. This cross-sectional observational study aimed to determine MCIDs for the app-based JACQLQ in assessing hay fever-related allergic conjunctivitis. This study used data from a crowdsourced, cross-sectional, observational study conducted via the smartphone app "AllerSearch" between February 1, 2018, and May 1, 2020. Participants were recruited through digital media and social networking platforms and voluntarily provided electronic informed consent. Participants completed the JACQLQ, which includes items on daily activity and psychological well-being, as well as a visual analog scale to measure stress levels related to hay fever. Data were collected through the app, ensuring comprehensive user input. MCIDs were determined using both anchor- and distribution-based methods. The face scale of the JACQLQ Domain III and stress level scale for hay fever were used as anchors to estimate the MCID; ranges were derived from these MCID estimates. In the distribution-based method, MCIDs were calculated using half the SD and SE of the JACQLQ Domain II scores. SEs were derived from the intraclass correlation coefficient of an app-based JACQLQ test-retest reliability metric. A total of 17,597 individuals were identified, of which 15,749 individuals provided electronic consent. After excluding those with incomplete data, 7590 participants with hay fever were included in the study (mean age 35.3, SD 13.9 years; n=4331, 57.1% of women). MCID ranges calculated using the anchor-based method were 1.0-6.9, 1.2-5.6, and 2.1-12.6 for daily activity, psychological well-being, and total JACQLQ Domain II scores, respectively. Using the distribution-based method, the intraclass correlation coefficients were odds ratio (OR) 0.813 (95% CI 0.769-0.849) for daily activity, OR 0.791 (95% CI 0.743-0.832) for psychological well-being, and OR 0.841 (95% CI 0.791-0.864) for total JACQLQ Domain II scores. In addition, the distribution-based method resulted in 2 MCIDs based on half the SD and SE of measurement for daily activity (4.8 and 4.2), psychological well-being (3.4 and 3.1), and total JACQLQ Domain II (7.8 and 6.4) scores. The final suggested MCID ranges for daily activity, psychological well-being, and total JACQLQ Domain II scores were 4.2-6.0, 3.1-4.7, and 6.4-10.5, respectively. MCID ranges for the JACQLQ estimation could help to standardize the app-based quality of life assessment for patients with hay fever-related allergic conjunctivitis. These MCIDs enhanced the precision of remote symptom monitoring and facilitated timely, data-driven interventions, ultimately improving the overall management and outcomes of allergic conjunctivitis through mobile health platforms.

Bacterial diversity and lysozyme activity of raw buffalo milk: a case study on milk collection tanks from selected farms

ABSTRACT Approximately 15% of the milk produced in the world comes from buffaloes. In this study, the microbiome and lysozyme activities of buffalo milk in the Tepecik region were investigated. Samples were taken from ten different farms and analyzed. The average lysozyme activities were 59.858 units × 10−3/mL. Taxonomic analyses showed that Lactococcus, Acinetobacter, Moraxella, Streptococcus, Anoxybacillus, Aeromonas generally constituted the dominant bacterial groups. Low lysozyme activities and Staphylococcus aureus and Micrococcus luteus values showed that the milk taken from ten farms was mastitis free. The presence of Acinetobacter, Moraxella, Anoxybacillus and Aeromonas bacteria, which pose a pathogenic risk for milk, indicates that proper sanitation of milking machines are required. Pseudomonas, a psychrophilic bacterium, was not detected in most products, but was detected in very small amounts in some products. This work sheds a light on future studies that covers lysozyme activity measurement combined with DNA sequencing for food safety in dairy industry.

Physical Activity Measurement in People with Spinal Cord Injury: A Comparative Review of Different Questionnaires.

Physical activity (PA) provides great health benefits for people with spinal cord injury (SCI). Consequently, the design and implementation of PA interventions addressed to this population is needed. To rigorously evaluate these interventions, the use of valid and comprehensive PA measures is crucial. Since the suitability of PA assessment tools might differ among different populations, and considering that questionnaires are one of the most frequently used tools to quantify PA, the purpose of this comparative review was to examine nine questionnaires that have been used to assess PA in people with SCI. All the questionnaires were analyzed in depth in regard to three main dimensions: (1) SCI-specific development; (2) PA domains measured and PA intensity classification; and (3) reliability and validity. After careful consideration of the evidence available on all these aspects, it is suggested that the most suitable questionnaires to be used in PA research in the SCI population are the PARA-SCI and the LTPAQ-SCI[R]. To conclude, the strengths and limitations of these two questionnaires are discussed, and specific recommendations to SCI researchers and practitioners regarding the suitability, according to the context and characteristics, of the research/intervention are provided.

Cage Architecture and Reactivity are Preserved in Cysteine‐Mutated Ferritin

AbstractThe role of solvent‐exposed cysteines as reactive sites for bioconjugation with a variety of metal drugs or fluorescent probes is emerging in the use of human H‐ferritin (HuHf) as a nanocarrier for targeting various tumor cell lines. Here, we have investigated the role of these residues in controlling the structural stability and ferroxidase activity by analyzing the properties of three variants: C90A, C90AC102A, and C130A. Protein folding and cage assembly were unchanged. Ferroxidase activity was also unaffected, indicating that these cysteines are not involved in either the catalytic activity or the overall iron(II) uptake process. For comparison, activity measurements were also performed on two derivatives involving the solvent‐exposed cysteine residues.

Evaluating drought impact on white cabbage: Plant stress response and soil microbiome adaptation

Drought is a dangerous abiotic stress, worsened by climate change, that threatens agriculture by reducing yields, degrading soil, and hindering plant growth. Since the soil microbial community has great potential to mitigate the negative effects of drought, research into how these bacterial communities adapt to drought and interact with plants is increasingly important for sustainable agriculture. In this study, 27-day old white cabbage (Brassica oleracea var. capitata f. alba) plants were exposed to a 13-day drought conditions. Following the treatment, we assessed the plant's stress response by evaluating its morphology, yield, photosynthetic parameters, pigment levels, stress markers, and mineral content. Additionally, changes in the soil microbiome were monitored through 16S rRNA amplicon sequencing and measurements of microbial enzyme activity. Plants under drought stress showed reduced growth and photosynthetic activity, along with increased stress markers compared to controls, confirming activation of stress response mechanisms. In contrast, the soil microbiome demonstrated greater resilience, maintaining stable community diversity despite the drought conditions. Notably, a decrease in the abundance of Gemmatimonadota was observed, along with an increase in arylsulfatase activity in drought-stressed soils. Our results emphasise the complexity of interactions between soil, microorganisms and drought, highlighting that plants are generally more sensitive to drought than their associated soil microbiomes. These results could serve as a valuable basis for future studies focused on screening and understanding the role of drought-tolerant bacteria that could provide potential solutions to improve crop resilience.

Quantification of [99mTc]Tc-HDP bone SPECT/CT: can we improve the body weight based standardized uptake value with a more robust normalization?

The introduction of quantitative SPECT/CT allows more objective assessments of tracer accumulation in SPECT. However standardized uptake values (SUV) still do not play a big role for orthopedic or oncologic questions. With a more reliable normalization, the use of quantitative measures might also be of use for a more objective assessment of lesions. We retrospectively included patients that received a quantitative [99mTc]-HDP bone SPECT/CT scan of the lumbar spine for 4 body weight (BW) categories. Measurements of bone activity (kBq/cc) and bone density in Hounsfield Units (HU) in a standard volume of interest in the femur, the first and the fifth lumbar vertebra of all patients, without active disease within these regions was made. Correlations between tracer uptake and clinical parameters (BW, height, age, gender) were assessed with a multiple regression and based on the model coefficients, a correction formula was calculated and applied. The strongest correlation between measured activity in L1 and patient parameters was found for BW (r= -0.64, p < 0.001), compared to height (r = -0.28, p = 0.002) and age (r = -0.34, p = 0.001). Furthermore, there was a weak positive correlation between tracer accumulation and bone density (r: 0.35, p < 0.001). Using standard normalization with BW there was a very weak positive correlation between SUVBW at L1 and BW with a slight overestimation in heavier subjects (r = 0.15, p = 0.09). The calculated correction based on the multiple regression of activity as dependent variable, and weight, age and bone density as significant predictors resulted in more robust uptake values with non-significant associations to BW, height, age or density. However, there was still a wide interindividual range of values for normalized bone activity. Using an age, bone density and weight-based normalization significantly decreased the interindividual variability of normal uptake on quantitative SPECT/CT compared to the regularly used BW adjusted SUVBW. However, a generalized normalization is difficult in the presence of strong patient effects, not attributable to the measured clinical variables.

Study of the optical rotatory of potassium titanyl phosphate using the advanced dual-wavelength polarimetric method

A dual-wavelength high-accuracy universal polarimeter was applied to the circular birefringence and optical activity measurement in potassium titanyl phosphate (KTP) nonlinear crystal. The experimental setup used two single-mode He-Ne lasers with close wavelengths of 594 and 633 nm as light sources. Measurement has been carried out for two crystal settings in directions of a 45-degree relative angle to the [100] and [010] crystallographic axes. Multiple light reflections inside the crystal sample were considered when processing the results of the polarimetric measurements. The results have been analysed using the optical transmission function for the polariser-sample-analyser system, and 2D intensity contour maps made it possible to determine the phase parameters, systematic errors, and eigenwaves ellipticity. It was found that the gyration tensor component of the KTP crystal is equal to g12 = 1.4 ⋅ 10−5 which in terms of optical rotatory power corresponds to the very small magnitude of the rotation value of 2.3 deg/mm.