One of the main challenges in analyzing chemical messengers in the brain is the optimization of tissue sampling and preparation protocols. Limiting postmortem time and terminating enzyme activity is critical to identify low-abundance neurotransmitters and neuropeptides. Here, we used a rapid and uniform conductive heat transfer stabilization method that was compared with a conventional fresh freezing protocol. Together with a selective chemical derivatization method and an optimized quantitation approach using deuterated internal standards, we spatially mapped neurotransmitters and their related metabolites by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) in rat brain tissue sections. Although the heat stabilization did not show differences in the levels of dopamine, norepinephrine, and serotonin, their related metabolites 3,4-dihydroxyphenylacetaldehyde, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 3-methoxy-4-hydroxyphenylacetaldehyde, dihydroxyphenylethyleneglycol, and 5-hydroxyindoleacetic acid were all significantly lower, indicating reduced neurotransmitter postmortem turnover ratios. Heat stabilization enabled detection of an increased number and higher levels of prodynorphin, proenkephalin, and tachykinin-derived bioactive neuropeptides. The low-abundant C-terminal flanking peptide, neuropeptide-γ, and nociceptin remained intact and were exclusively imaged in heat-stabilized brains. Without heat stabilization, degradation fragments of full-length peptides occurred in the fresh frozen tissues. The sample preparation protocols were furthermore tested on rat brains affected by acute anesthesia induced by isoflurane and medetomidine, showing comparable results to non-anesthetized animals on the neurotransmitters level without significant changes. Our data provide evidence for the potential use of heat stabilization prior to MALDI-MSI analyses to improve the examination of the in vivo state of neuronal chemical messengers in brain tissues not impacted by prior acute anesthesia.
- MeSH
- Rats MeSH
- Brain Chemistry * physiology MeSH
- Brain * metabolism MeSH
- Neurons * metabolism chemistry MeSH
- Neurotransmitter Agents * metabolism analysis MeSH
- Rats, Sprague-Dawley MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization * methods MeSH
- Hot Temperature * MeSH
- Freezing MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Breast milk, as the optimal food for infants and young children, contains all the components necessary for proper growth and development. It is a rich source of both essential nutrients and biologically active factors, making breast milk a unique food with scientifically proven health-promoting properties. Among the entire range of biologically active factors, breast milk microorganisms and prebiotic factors, in the form of breast milk oligosaccharides, occupy an important place. The aim of our research was to determine the occurrence of bacteria with probiotic potential, belonging to the Lactobacillaceae family, in the environment of breast milk and breast milk oligosaccharides. The study included 63 human milk samples from breastfeeding women at various stages of lactation. Microorganism identification based on culture tests and MALDI TOF/MS, macronutrient analysis using the MIRIS human milk analyser, as well as analysis of human milk oligosaccharides using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry were performed. The results have shown that breast milk from different breastfeeding women is characterized by great diversity in terms of the presence of Lacto-bacillaceae bacteria in its microbiological composition. These bacteria were present in 22.2 % of the tested breast milk samples. Analysis of the human milk oligosaccharide profile revealed a slightly higher content of prebiotic factors in breast milk samples containing Lactobacillaceae, including 2'-fucosyllactose, oligosaccharide occurring in the highest amount in breast milk.
PURPOSE: This study aimed to compare the image quality of the Siemens Biograph mCT40 (photomultiplier-based system - PMT) and the Siemens Vision600 (silicon photomultiplier-based system - SiPM) using a modified NEMA IEC Body phantom (Data Spectrum). METHODS: SiPM-based Vision600 has a smaller crystal size (3.2 × 3.2 mm vs. 4.0 × 4.0 mm in the PMT-based mCT40), resulting in better spatial resolution. Enhanced time-of-flight (TOF) timing and higher sensitivity leads to nearly four times higher effective sensitivity. The standard NEMA IEC Body phantom was modified with a 3D-printed holder to accommodate also Hollow and Micro Hollow Spheres of 15.4 mm, 12.4 mm, 7.9 mm, 6.2 mm, 5.0 mm, and 4.0 mm. Each of the three acquisition sessions per scanner included 18 time points and spanned 5.6 half-lives to assess system performance at varying activity concentrations in the field of view. RESULTS: Recovery curves for both systems were similar when identical post-reconstruction filters were applied. The SiPM-based Vision600 system detected smaller sources at significantly lower activity concentrations, and the variations in standardized uptake value (SUVmax, SUVA50) measurements were generally smaller compared to those of the PMT-based system. The two smallest sources became undetectable below 63 MBq and 16 MBq on the PMT system, versus 20 MBq and 6.5 MBq on the SiPM system. CONCLUSIONS: SiPM technology demonstrated superior performance compared to PMT in detecting small sources in low-activity scenarios and provided more robust quantification results. It is recommended to use averaged SUV metrics, such as SUVA50 or SUVpeak.
The coronavirus disease 2019 (COVID-19) pandemic and respective shutdowns dramatically altered human activities, potentially changing human pressures on urban-dwelling animals. Here, we use such COVID-19-induced variation in human presence to evaluate, across multiple temporal scales, how urban birds from five countries changed their tolerance towards humans, measured as escape distance. We collected 6369 escape responses for 147 species and found that human numbers in parks at a given hour, day, week or year (before and during shutdowns) had a little effect on birds' escape distances. All effects centered around zero, except for the actual human numbers during escape trial (hourly scale) that correlated negatively, albeit weakly, with escape distance. The results were similar across countries and most species. Our results highlight the resilience of birds to changes in human numbers on multiple temporal scales, the complexities of linking animal fear responses to human behavior, and the challenge of quantifying both simultaneously in situ.
Objectives. The realization of manned deep space flights places multiple demands on the entire crew. In terms of the structure and dynamics of the relationships and bonds between crew members, some of the main risks are (1) a decline in mood, morale and increased irritability among crew members (the so-called third quarter phenomenon), (2) the breakup of the crew into multiple subgroups, (3) the transfer of negative emotions from the crew to the mission control centre. The present study aims to describe, within the framework of the social action research model, these risks in their interaction during an analogue crew isolation study. Sample and settings. The isolation study of a gender-mixed crew of 17 days duration was conducted at the IBMP RAS Institute in Moscow, in a joint organization with the American NASA. The study involved 6 participants, 3 women and 3 men, of both Russian and American nationalities. Statistical analyses. Relationship and bonds scales, as the basis of the sociomapping method, were used to assess the structure and dynamics of relationships and bonds within the group. Statistically, the dynamics of relationships were analysed through Shewhartʼs control charts. The assessment of control centre support was analysed through Friedmanʼs ANOVA for repeated measures. Free qualitative responses were analysed through frequency content analysis. The structure of relationships and associations was analysed by the Mann-Whitney test. Results. Increased levels of communication and cooperation were detected during the first days of isolation, which may have been related to the group’s adjustment to coexistence and cooperation. In contrast, a decrease in the scales occurred after the middle of the isolation (possible occurrence of the third quarter phenomenon) and at the end of the 17-day isolation. The decline after the middle of the isolation could, according to the key experiences reported the previous day, be related to the awareness of bridging the mid-term of the experiment, challenging work tasks and unfavourable external circumstances. The decline at the end of the isolation could have been related to fatigue from previous sleep deprivation, the depletion of crew members’ resources, the nature of the activities performed in the final stage of the mission, and awareness of the ensuing post-isolation period. According to the analysis, the crew did not divide into subgroups based on gender. The level of support from the control centre was stable and high throughout the isolation. Limitations. Efforts to capture the situation in the group in a comprehensive manner, together with the absence of the research team during data collection and the inability to discuss the findings with the crew, do not allow for clear interpretations of the context of the phenomena observed.
The nearest-neighbour distance is an important property of a group, as individuals can obtain environmental information more quickly and easily from nearby individuals. We examined whether distance to the nearest neighbour affected two components of escape behaviour - alert distance (AD) and flight initiation distance (FID) - in an urban population of hooded crows Corvus cornix, while controlling for confounding variables. We did not find evidence that AD and FID were influenced by the nearest neighbour distance. However, both AD and FID were negatively affected by feeding activity of individuals - focal crows alerted later and escaped at shorter distance if they were feeding during our approach. In addition, AD and FID were positively related to starting distance and grass coverage. The lack of evidence for the nearest neighbour effect on escape behaviour of crows may be due to: (1) disturbance by close neighbours that may impede antipredator behaviour of focal birds, (2) variable distribution of familiar, dominant or experienced individuals within a flock, and (3) dynamic change in position of the nearest neighbour during the potential predator approach.
- MeSH
- Behavior, Animal physiology MeSH
- Feeding Behavior physiology MeSH
- Escape Reaction * physiology MeSH
- Crows * physiology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Spontánní disekce koronární tepny je jednou z příčin akutního koronárního syndromu. Nejčastěji se vyskytuje u mladých žen a může vzniknout po fyzické nebo emoční zátěži. Vyskytuje se u pacientů s fibromuskulární dysplazií či zánětlivými onemocněními. Její léčba může být konzervativní a v případě pokračující ischemie myokardu je indikována revaskularizace, což je spojeno s rizikem vzniku iatrogenní disekce koronární tepny. V kazuistice popisujeme případ mladé ženy, u které vznikla disekce koronární tepny při vyhlídkovém letu. U pacientky byla pro pokračující bolesti na hrudi indikována perkutánní koronární intervence, která byla komplikována uzávěrem kmene levé koronární tepny. V diskusi je řešen možný vztah hypotyreózy a spontánní disekce koronární tepny.
Spontaneous coronary artery dissection is one of the causes of acute coronary syndrome. It is most common in young women and may occur after physical or emotional stress and may be associated with fibromuscular dysplasia or inflammatory diseases. Its treatment may be conservative and revascularization is indicated in case of ongoing myocardial ischemia, which is associated with the risk of iatrogenic coronary artery dis- section. In this case report, we present a young woman who developed coronary artery dissection during a sightseeing flight. Due to ongoing chest pain, the patient was indicated for PCI, which was complicated by left main coronary artery occlusion. The possible relationship between hypothyroidism and spontaneous coronary artery dissection is discussed.
- Keywords
- Acute coronary syndrome, Hypothyroidism, Spontaneous coronary artery dissection, Akutní koronární syndrom, Hypotyreóza, Spontánní disekce koronární tepny,
- MeSH
- Diagnostic Techniques, Cardiovascular MeSH
- Dissection, Blood Vessel * classification pathology therapy MeSH
- Adult MeSH
- Hypothyroidism complications MeSH
- Platelet Aggregation Inhibitors pharmacology therapeutic use MeSH
- Percutaneous Coronary Intervention methods MeSH
- Coronary Vessels * pathology MeSH
- Humans MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Female MeSH
The objective of this study was to assess the susceptibility of cefiderocol against multidrug-resistant carbapenemase-producing and nonproducing bacteria. The panel comprised 182 isolates of the order Enterobacterales, and 40 strains of Pseudomonas aeruginosa. Antimicrobial susceptibility testing has been performed using broth microdilution method according to the European Committee on Antimicrobial Susceptibility Testing recommendations. Mass spectrometry matrix-assisted laser desorption/ionization-time of flight mass spectrometry and carbapenemase-producing test were used to verify the presence of carbapenemases in clinical isolates. The genetic expression of single carbapenemases (blaKPC, blaOXA-48, blaNDM, blaVIM, blaIMP, blaGES) was determined by real-time polymerase chain reaction. Cefiderocol exhibited a good activity against the majority of strains tested in this study. Altogether, growth of 81.9% (n = 149) strains of the order Enterobacterales and 77.5% (n = 31) of P. aeruginosa isolates were inhibited at minimal inhibitory concentration (MIC) ≤2 mg/L. Values MIC50/MIC90 were 0.5/8 mg/L for enterobacteria, and 1/8 mg/L for P. aeruginosa. One isolate (Klebsiella pneumoniae) harboring two carbapenemases (blaOXA-48, blaNDM) had cefiderocol MIC 0.5 mg/L. In enterobacteria resistant to cefiderocol, blaNDM carbapenemase prevailed (43.3%, n = 29), followed by blaOXA-48 (31.3%, n = 21) and blaKPC (4.5%, n = 3). blaIMP (n = 8) and blaVIM (n = 1) metallo-β-lactamases dominated in cefiderocol-resistant P. aeruginosa (n = 9) isolates. Very good susceptibility (100%) to this drug showed blaGES-positive strains of P. aeruginosa (n = 8) and isolates resistant to meropenem without confirmed carbapenemase gene (n = 10). In this study, cefiderocol demonstrated potent activity against important nosocomial pathogens, therefore, therapeutic options of this drug against multidrug-resistant bacteria should be considered.
Bacterial contamination of semen has become an important contributor to the reduced shelf life of insemination doses in the poultry industry, which is why antibiotics (ATBs) are an important component of semen extenders. Due to a global rise in antimicrobial resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent possible bacterial contamination of rooster ejaculates. Two selected extenders free from or containing 31.2 μg/mL kanamycin (KAN) were used to process semen samples from 63 healthy Lohmann Brown roosters. Phosphate-buffered saline without ATBs was used as a control. The extended samples were stored at 4 °C for 24 h. Sperm motility, viability, mitochondrial activity, DNA integrity and the oxidative profile of each extended sample were assessed following 2 h and 24 h of storage. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with KAN ensured a significantly higher preservation of sperm quality in comparison to their KAN-free counterparts. Bacterial load was significantly decreased in diluents supplemented with ATBs (p ≤ 0.001); however, KAN alone was not effective enough to eradicate all bacteria since several Escherichia coli, Enterococcus faecalis, Enterococcus faecium and Micrococcus luteus were retrieved from samples extended in KAN-supplemented commercial extenders. As such, we may suggest that more focus should be devoted to the selection of an optimal combination and dose of antibiotics for poultry extenders, which should be accompanied by a more frequent bacteriological screening of native as well as extended poultry semen.
- Publication type
- Journal Article MeSH
This study aimed to characterize the bacterial profiles and their association with selected semen quality traits among two chicken breeds. Thirty Lohmann Brown and thirty ROSS 308 roosters were selected for semen quality estimation, including sperm motility, membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. The oxidative profile of the semen, including the production of reactive oxygen species (ROS), antioxidant capacity, protein, and lipid oxidation, were assessed as well. Moreover, the levels of pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1, IL-6) and C-reactive protein, as well as the concentrations of selected antibacterial proteins (cathelicidin, β-defensin and lysozyme) in the seminal plasma were evaluated with the enzyme-linked immunosorbent assay. The prevailing bacterial genera identified by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were Citrobacter spp., Enterococcus spp., Escherichia spp. and Staphylococcus spp. While the bacterial load was significantly higher in the ROSS 308 line (p < 0.05), a higher number of potentially uropathogenic bacteria was found in the Lohmann Brown roosters. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains, particularly to ampicillin, tetracycline, chloramphenicol, and tobramycin. Furthermore, Lohmann Brown ejaculates containing an increased proportion of Escherichia coli presented with significantly (p < 0.05) elevated levels of TNF-α and IL-6, as well as ROS overproduction and lipid peroxidation. Inversely, significantly (p < 0.05) higher levels of β-defensin and lysozyme were found in the semen collected from the ROSS 308 roosters, which was characterized by a higher quality in comparison to the Lohmann Brown roosters. In conclusion, we emphasize the criticality of bacteriospermia in the poultry industry and highlight the need to include a more complex microbiological screening of semen samples designated for artificial insemination.
- Publication type
- Journal Article MeSH
