Petterssonthaysen3960
Recently, we established an experimental setup protocol to perform the population transfer from half-integer quadrupolar spin to 1H nuclei under fast MAS in the context of MQ-HETCOR experiments. In this article, we further develop the high-resolution 2D HETCOR methods by ST-based approaches, making use of the sensitivity advantage of STMAS over its MQMAS counterpart. In a similar manner to the previous work, which utilized CP and RINEPT for the population transfer, we also demonstrate the experimental setup protocol for PRESTO. Using 23Na-1H and 27Al-1H spin systems of powder samples, we compare a series of MQ/ST-HETCOR 2D spectra to discuss the pros and cons of the distinct MQ/ST-based approaches for spin 3/2 and 5/2 nuclei, respectively. We also incorporate two experimental tricks to reduce the experimental time of such long 2D experiments, the Optimized Rotor-Synchronization (ORS) and the Non-Uniform Sampling (NUS), in the context of high-resolution spectra of half-integer quadrupolar spin nuclei.Cost-effective and portable MRI systems operating at Earth-field would be helpful in poorly accessible areas or in developing nations. Furthermore Earth-field MRI can provide new contrasts opening the way to the observation of pathologies at the biochemical level. However low-field MRI suffers from a dramatic lack in detection sensitivity even worsened for molecular imaging purposes where biochemical specificity requires detection of dilute compounds. In a preliminary spectroscopic approach, it is proposed here to detect protease-driven hydrolysis of a nitroxide probe thanks to electron-nucleus Overhauser enhancement in a home-made double resonance system in Earth-field. The combination of the Overhauser effect and the specific enzymatic modification of the probe provides a smart contrast reporting the enzymatic activity. The nitroxide probe is a six-line nitroxide which lines are shifted according to its substrate/product state, which requires quantum mechanical calculations to predict EPR line frequencies and Overhauser enhancements at Earth field. The NMR system is equipped with a 13-mT prepolarization coil, a 153-MHz EPR coil and a 2-kHz NMR coil. Either prepolarized NMR or DNP-NMR without prepolarization provide NMR spectra within 3 min. The frequency dependence of Overhauser enhancement was in agreement with theoretical calculations. Protease-mediated catalysis of the nitroxide probe could only be measured through the Overhauser effect with 5 min time resolution. Future developments shall open the way for the design of new low-field DNP-MRI systems.Pulsed 19F ENDOR spectroscopy provides a selective method for measuring angstrom to nanometer distances in structural biology. Here, the performance of 19F ENDOR at fields of 3.4 T and 9.4 T is compared using model compounds containing one to three 19F atoms. CF3 groups are included in two compounds, for which the possible occurrence of uniaxial rotation might affect the distance distribution. At 9.4 T, pronounced asymmetric features are observed in many of the presented 19F ENDOR spectra. Data analysis by spectral simulations shows that these features arise from the chemical shift anisotropy (CSA) of the 19F nuclei. This asymmetry is also observed at 3.4 T, albeit to a much smaller extent, confirming the physical origin of the effect. The CSA parameters are well consistent with DFT predicted values and can be extracted from simulation of the experimental data in favourable cases, thereby providing additional information about the geometrical and electronic structure of the spin system. The feasibility of resolving the CSA at 9.4 T provides important information for the interpretation of line broadening in ENDOR spectra also at lower fields, which is relevant for developing methods to extract distance distributions from 19F ENDOR spectra.
Safe exposure levels for industrial chemicals are a prerequisite to the safety of workers in occupational settings.
The application areas of the benchmark dose (BMD) approach have tremendously increased in recent years. Quantitative analyzes of dose-response relationships of genotoxic chemicals are among these application areas too. This study investigates the applicability of sister chromatid exchange (SCE) frequencies in lymphocytes of lead-exposed workers to derive a biological limit value (BLV) for inorganic lead. To this end, our previously published occupational lead exposure data were pooled and re-examined by using the BMD approach. Linsitinib molecular weight Subsequently, we determined the point of departure (POD) value for lead-induced SCE frequencies in lymphocytes. Accordingly, the blood lead concentrations and SCE frequencies in lymphocytes of 26 control and 108 lead-exposed male voluntary workers employed in a battery manufacturing plant were subjected to BMD modeling to determine the BMD confidence interval (BMD-CI).
According to our data set, benchmark dose lower bound (BMDL) of 6.55 μg Pb/dL blood for the SCE frequencies in lymphocytes of lead-exposed workers has been obtained.
The blood lead concentration of 6.55 μg/dL might be proposed as the BLV for lead and its inorganic lead compounds based on our dataset.
The blood lead concentration of 6.55 μg/dL might be proposed as the BLV for lead and its inorganic lead compounds based on our dataset.
Despite existing occupational lead exposure prevention regulations, Lithuanian shooting range workers still complain of chronic lead poisoning related symptoms. This indicates a poor understanding of occupational safety when working in lead-polluted environments.
20 men, whose age ranged from 32 to 57 (mean 41.8 ± 10 years), were consulted at the Toxicology Centre at the Republican Vilnius university hospital in Vilnius, Lithuania in the 2016-2019 year period. All of the patients were working as shooting instructors, with their work experience varying from 2 to 30 years. Clinical examination showed blood lead levels ranging from 5.64 μg/dL to 45.8 μg/dL (norm for occupational exposure - <40 μg/dL). Main symptoms were fatigue (12 patients out of 20), dizziness (5/20), arthralgia (5/20). Other symptoms included impaired memory (3/20), nausea (3/20), sleep disorders (3/20), metallic or sweet taste (3/20), dermatological disorders (3/20), coxarthrosis (2/20), balance disorders (2/20), paresthesia (2/20), abdominal pain (2/20) and others. 4 patients were asymptomatic.
Shooting range employees are highly vulnerable to daily lead exposure. Even low constant elevated blood lead concentrations can have significant toxic effects over time.
Shooting range employees are highly vulnerable to daily lead exposure. Even low constant elevated blood lead concentrations can have significant toxic effects over time.
To examine associations between local and systemic symptoms and the wear of the tin weld of Essure implants.
study of a series of cases.
Two French hospitals.
Eighteen patients explanted by hysterectomy and salpingectomy for removal of their Essure implants between September 2019 and July 2020, have had a common anatomopathological process.
anatomopathological examination by optical microscopy and mineralogical analysis of the fallopian tube or uterine horn with scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX). Evaluation of local and systemic symptoms with a questionnaire. Examination of blood metal assays (nickel, chromium, and tin).
anatomopathological examination highlights foreign body granulomas, fibrosis, adenomyosis, nonspecific inflammation, cysts and myomas in the Fallopian tubes, uterine horns, or both and mentions the presence of foreign bodies in seven cases. SEM-EDX analyses showed, systematically, the presence of tin particles integrated in the wall near ted to organotin in the patients' bodies.
our new anatomopathological process systematically demonstrates the presence of tin particles in tissue near the weld. These particles could be responsible for granulomatous inflammations as well as local symptoms. Many of the systemic symptoms are consistent with chronic organotin poisoning but further studies are needed to find out whether tin from the solder can be converted to organotin in the patients' bodies.In livestock, selection programs on reproductive traits are time consuming due to long generation interval and low heritability; however understanding the genetic factors that influence reproductive performance facilitates an accurate selection and genetic improvement of these quantitative traits. Therefore, the aim of this study was to identify the effect of lactation order and polymorphisms of FGFBP1, leptin, κ-casein, and αs1-casein genes on reproductive performance in dromedary she-camels. Blood samples were collected from one hundred she-camels using vacutainer tube containing EDTA as an anticoagulant for DNA extraction. PCR-DNA sequencing approach was performed to investigate the polymorphisms in fragments for coding sequence (CDS) parts of FGFBP1 (539-bp) and leptin (359-bp), 5'-flanking region of κ-casein (488-bp) and intervening non-coding fragment spanning from exon 4 to exon 6 (924-bp) of αs1-casein genes. Results revealed that there were single nucleotide polymorphisms (SNPs) in the investigated genes between enrolled she-camels except for leptin gene that elicited a monomorphic pattern. The identified SNPs allocated camels into different groups according to which animal harbored the explored SNPs. Multiple linear regression analysis (MLR) reveled that identified SNPs and parity order had significant effects on age at first calving (AFC), days open (DO), calving interval (CI), number of services/conception (NS/C) and milk yield traits. Determination coefficients (R2) value indicated also that variability in the phenotypic measurements of studied traits might be correlated with the identified SNPs in the reproduction related genes. This study highlights that parity order has a remarkable effect on reproductive performance. Single nucleotide polymorphisms in the investigated genes could be also used as proxy predictors and genetic markers that permit a marker assisted selection for reproductive performance traits in dromedary she-camels.Trehalose is a disaccharide with multiple important biological activities. In many cell types, Trehalose regulates the physiological behaviors of proliferation, apoptosis and autophagy. But the effects of trehalose on ASMCs have never been reported. Here, we showed that trehalose activated autophagy of ASMCs at low dose, inhibited proliferation and induced apoptosis of ASMCs at high dose. Further study, we found the cell cycle was arrested in S and G2\M phases, the expression of CyclinA1 and CyclinB1 decreased. Then, we investigated the ratio of Bcl-2/Bax was drastically reduced. Next, we detected an important transcription factor TFEB, which is closely related to autophagy. We found TFEB was highly activated with trehalose treatment. And many downstream autophagy-related genes of TFEB were also up-regulated. In summary, trehalose plays an important role on the regulation of proliferation, apoptosis and autophagy of ASMCs.The prevalence of phylogenetic constraints in Rubisco evolution has been emphasised recently by (Bouvier et al., 2021), who argued that phylogenetic inheritance limits Rubisco adaptation much more than the biochemical trade-off between specificity, CO2 affinity and turn-over. In this Opinion, we have critically examined how a phylogenetic signal can be computed with Rubisco kinetic properties and phylogenetic trees, and we arrive at a different conclusion. In particular, Rubisco's adaptation is partly driven by C4 vs. C3 photosynthetic conditions in Angiosperms, apparent phylogenetic signals being mostly due to either homoplasy, computation artefacts or the use of nearly identical sister species. While phylogenetic inheritance of an ancestral enzyme form probably has some role in Rubisco's adaptation landscape, it is a minor player, at least compared to microenvironmental conditions such as CO2 and O2 concentrations.
