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Tree Physiology May 2016Matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI) was employed to detect monolignol glucosides in differentiating normal and compression...
Matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI-MSI) was employed to detect monolignol glucosides in differentiating normal and compression woods of two Japanese softwoods, Chamaecyparis obtusa and Cryptomeria japonica Comparison of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry collision-induced dissociation fragmentation analysis and structural time-of-flight (MALDI-TOF CID-FAST) spectra between coniferin and differentiating xylem also confirmed the presence of coniferin in differentiating xylem. However, as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and MALDI-TOF CID-FAST spectra of sucrose were similar to those of coniferin, it was difficult to distinguish the distribution of coniferin and sucrose using MALDI-MSI and collision-induced dissociation measurement only. To solve this problem, osmium tetroxide vapor was applied to sections of differentiating xylem. This vapor treatment caused peak shifts corresponding to the introduction of two hydroxyl groups to the C=C double bond in coniferin. The treatment did not cause a peak shift for sucrose, and therefore was effective in distinguishing coniferin and sucrose. Thus, it was found that MALDI-MSI combined with osmium tetroxide vapor treatment is a useful method to detect coniferin in differentiating xylem.
Topics: Chamaecyparis; Cinnamates; Cryptomeria; Osmium Tetroxide; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Wood
PubMed: 26507270
DOI: 10.1093/treephys/tpv116 -
Folia Morphologica 2022Cerebral white matter consists mainly of axons surrounded by myelin sheaths, which are grouped to form association, commissural, and projection fasciculi. The aim of our...
Axonal quantification of the white matter association fasciculi in cerebral hemispheres of cow (Bos taurus), pig (Sus scrofa domesticus) and rabbit (Oryctolagus cuniculus).
BACKGROUND
Cerebral white matter consists mainly of axons surrounded by myelin sheaths, which are grouped to form association, commissural, and projection fasciculi. The aim of our work was to quantify and compare under the microscope the axons of the white matter association fasciculi in the cerebral hemispheres of cow (Bos taurus), pig (Sus scrofa domesticus) and rabbit (Oryctolagus cuniculus) indirectly by identification of their myelin sheaths.
MATERIALS AND METHODS
The samples were taken from 30 cerebral hemispheres: 10 cow, 10 pig and 10 rabbit (15 right and 15 left). They were obtained following a protocol based on the Talairach-Tournoux coordinate system for human and primate brains. The slides were stained with Luxol Fast Blue, observed by optical microscopy, and photographed at 600×. Samples were also prepared for observation in scanning transmission electron microscopy with osmium tetroxide. The myelin sheaths/axons were counted with the ImageJ software.
RESULTS
Statistically significant differences in the number of myelin sheaths per 410 μm² were found in the inferior and superior longitudinal fasciculi between the left and right hemispheres of cows, with predominance of the right hemisphere; and in the inferior occipitofrontal fasciculus of the rabbit with predominance of the left hemisphere.
CONCLUSIONS
The use of animal models for experiments in the cerebral fasciculi, especially pig, could give us a greater understanding of the behaviour of demyelinating and neurodegenerative diseases in humans.
Topics: Swine; Animals; Cattle; Female; Rabbits; Humans; White Matter; Sus scrofa; Myelin Sheath; Axons; Cerebrum
PubMed: 34750803
DOI: 10.5603/FM.a2021.0116 -
Frontiers in Neuroscience 2018Design and implantation of bionic implants for restoring impaired hair cell function relies on accurate knowledge about the microanatomy and nerve fiber pathways of the...
Design and implantation of bionic implants for restoring impaired hair cell function relies on accurate knowledge about the microanatomy and nerve fiber pathways of the human inner ear and its variation. Non-destructive isotropic imaging of soft tissues of the inner ear with lab-based microscopic X-ray computed tomography (microCT) offers high resolution but requires contrast enhancement using compounds with high X-ray attenuation. We evaluated different contrast enhancement techniques in mice, cat, and human temporal bones to differentially visualize the membranous labyrinth, sensory epithelia, and their innervating nerves together with the facial nerve and middle ear. Lugol's iodine potassium iodine (IKI) gave high soft tissue contrast in ossified specimens but failed to provide unambiguous identification of smaller nerve fiber bundles inside small bony canals. Fixation or post-fixation with osmium tetroxide followed by decalcification in EDTA provided superior contrast for nerve fibers and membranous structures. We processed 50 human temporal bones and acquired microCT scans with 15 μm voxel size. Subsequently we segmented sensorineural structures and the endolymphatic compartment for 3D representations to serve for morphometric variation analysis. We tested higher resolution image acquisition down to 3.0 μm voxel size in human and 0.5 μm in mice, which provided a unique level of detail and enabled us to visualize single neurons and hair cells in the mouse inner ear, which could offer an alternative quantitative analysis of cell numbers in smaller animals. Bigger ossified human temporal bones comprising the middle ear and mastoid bone can be contrasted with IKI and imaged in toto at 25 μm voxel size. These data are suitable for surgical planning for electrode prototype placements. A preliminary assessment of geometric changes through tissue processing resulted in 1.6% volume increase caused during decalcification by EDTA and 0.5% volume increase caused by partial dehydration to 70% ethanol, which proved to be the best mounting medium for microCT image acquisition.
PubMed: 30108474
DOI: 10.3389/fnins.2018.00501 -
Adipocyte Dec 2019Intramuscular fat (IMF) accumulates in muscles of the rotator cuff after tendon tear. The number and cross-sectional area of fat clumps and of adipocytes were quantified...
Intramuscular fat (IMF) accumulates in muscles of the rotator cuff after tendon tear. The number and cross-sectional area of fat clumps and of adipocytes were quantified on osmium tetroxide stained sections of the proximal, middle and distal quarters of SSP muscles 4, 8 and 12 weeks after SSP tendon division in a rabbit model. Linear mixed-effects models were fitted to the data and statistical significance was evaluated by ANOVA. Both the number (P<0.001) and cross-sectional area (P<0.0005) of fat clumps increased after tendon detachment while time had no significant effect (both at P>0.01). IMF accumulation was more important in the distal quarter of detached SSP muscle near tendon sectioning and characterized by increases of the number (P<0.0005) and cross-sectional area of fat clumps (P<0.0005) compared to the proximal quarter. Adipocyte number increased after tendon detachment (P<0.0005) and over time (P<0.01). The cross-sectional area of adipocytes increased in the detached group compared to controls (P<0.01) while time had no significant effect (P>0.01). Interestingly, the number of adipocytes in the distal quarter increased (P<0.0005) but the cross-sectional area was smaller (P<0.0005) compared to adipocytes in the proximal quarter. Adipocyte hyperplasia localized near tendon sectioning was the main contributor to fat accumulation in the detached SSP muscles.
Topics: Adipocytes; Animals; Female; Hyperplasia; Muscle, Skeletal; Rabbits; Rotator Cuff Injuries
PubMed: 31033395
DOI: 10.1080/21623945.2019.1609201 -
Veterinary World Mar 2024The pathogenesis of staphylococcal infections is mediated by virulence factors, such as enzymes, toxins, and biofilms, which increase the resistance of microorganisms to...
BACKGROUND AND AIM
The pathogenesis of staphylococcal infections is mediated by virulence factors, such as enzymes, toxins, and biofilms, which increase the resistance of microorganisms to host immune system evasion. Testing and searching for standardized multi-level algorithms for the indication and differentiation of biofilms at the early stages of diagnosis will contribute to the development of preventive measures to control the critical points of technology and manage dangerous risk factors for the spread of infectious diseases. This research aimed to study the main stages of s biofilm formation in experiments and to analyze the dynamics of respiratory syndrome development in chickens infected with these bacteria.
MATERIALS AND METHODS
Experimental reproduction of the infectious process was performed using laboratory models: 10-day-old White Leghorn chickens (n = 20). Before the experiments, the birds were divided into two groups according to the principle of analogs: Group I (control, n = 10): the birds were intranasally inoculated with 0.5 cm of 0.9% NaCl solution; Group II (experiment, n = 10): the birds were intranasally inoculated with a suspension of bacteria, 0.5 cm, concentration 1 billion/cm.
RESULTS
Colonization of individual areas of the substrate under study occurred gradually from the sedimentation and adhesion of single motile planktonic cells to the attachment stage of microcolony development. Staining preparations with gentian violet due to the "metachromosia" property of this dye are a quick and fairly simple way to differentiate cells and the intercellular matrix of biofilms. Fixation with vapors of glutaraldehyde and osmium tetroxide preserves the natural architecture of biofilms under optical and scanning electron microscopy. Pure cultures of microorganisms were isolated from the blood, lungs, small intestine, liver, kidneys, and spleen after 5-10 days during experimental infection of chickens. Clinical signs of respiratory syndrome developed within 5-6 days after infection. Acute and subacute serous-fibrinous airsacculitis, characterized by edema and thickening of the membranes of the air sacs and the presence of turbid, watery, foamy contents in the cavity, was the most characteristic pathomorphological sign. The signs of acute congestive hyperemia and one-sided serous-fibrinous pneumonia developed with significant thickening of fibrinous deposits. In Garder's gland, there was an increase in the number of secretory sections, indicating hypersecretion of the glands. In the lymphoid follicles of Meckel's diverticulum, leukocytes, usually lymphocytes, and pseudoeosinophils were detected.
CONCLUSIONS
Hydration and heteromorphism of the internal environment of biofilms determine the localization of differentiated cells in a three-dimensional matrix for protection against adverse factors. The most characteristic pathomorphological sign was the development of acute and subacute serous-fibrinous airsacculitis when reproducing the infectious process in susceptible models. There was a significant thickening of fibrinous deposits and signs of acute congestive hyperemia and one or two serous-fibrinous pneumonia developed.
PubMed: 38680142
DOI: 10.14202/vetworld.2024.612-619 -
Chemical & Pharmaceutical Bulletin 2017Total synthesis of sphingofungin E and 4,5-di-epi-sphingofungin E was achieved from an intermediate same as that of myriocin and mycestericin D via antipodal...
Total synthesis of sphingofungin E and 4,5-di-epi-sphingofungin E was achieved from an intermediate same as that of myriocin and mycestericin D via antipodal stereoselective dihydroxylations.
Topics: Amino Acids; Fatty Acids, Unsaturated; Magnetic Resonance Spectroscopy; Spectrometry, Mass, Fast Atom Bombardment; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet
PubMed: 28674344
DOI: 10.1248/cpb.c17-00322 -
Frontiers in Endocrinology 2016Bone marrow adipose tissue (MAT) contributes to increased circulating adiponectin, an insulin-sensitizing hormone, during caloric restriction (CR), but whether this...
BACKGROUND
Bone marrow adipose tissue (MAT) contributes to increased circulating adiponectin, an insulin-sensitizing hormone, during caloric restriction (CR), but whether this occurs in other contexts remains unknown. The antidiabetic thiazolidinediones (TZDs) also promote MAT expansion and hyperadiponectinemia, even without increasing adiponectin expression in white adipose tissue (WAT).
OBJECTIVES
To test the hypothesis that MAT expansion contributes to TZD-associated hyperadiponectinemia, we investigated the effects of rosiglitazone, a prototypical TZD, in wild-type (WT) or -Wnt10b mice. The latter resist MAT expansion during CR, leading us to postulate that they would also resist this effect of rosiglitazone.
DESIGN
Male and female WT or -Wnt10b mice (C57BL/6J) were treated with or without rosiglitazone for 2, 4, or 8 weeks, up to 30 weeks of age. MAT content was assessed by osmium tetroxide staining and adipocyte marker expression. Circulating adiponectin was determined by ELISA.
RESULTS
In WT mice, rosiglitazone caused hyperadiponectinemia and MAT expansion. Compared to WT mice, -Wnt10b mice had significantly less MAT in distal tibiae and sometimes in proximal tibiae; however, interpretation was complicated by the leakage of osmium tetroxide from ruptures in some tibiae, highlighting an important technical consideration for osmium-based MAT analysis. Despite decreased MAT in Wnt10b mice, circulating adiponectin was generally similar between WT and -Wnt10b mice; however, in females receiving rosiglitazone for 4 weeks, hyperadiponectinemia was significantly blunted in Wnt10b compared to WT mice. Notably, this was also the only group in which tibial adiponectin expression was lower than in WT mice, suggesting a close association between MAT adiponectin production and circulating adiponectin. However, rosiglitazone significantly increased adiponectin protein expression in WAT, suggesting that WAT contributes to hyperadiponectinemia in this context. Finally, rosiglitazone upregulated uncoupling protein 1 in brown adipose tissue (BAT), but this protein was undetectable in tibiae, suggesting that MAT is unlikely to share thermogenic properties of BAT.
CONCLUSION
TZD-induced hyperadiponectinemia is closely associated with increased adiponectin production in MAT but is not prevented by the partial loss of MAT that occurs in Wnt10b mice. Thus, more robust loss-of-MAT models are required for future studies to better establish MAT's elusive functions, both on an endocrine level and beyond.
PubMed: 27708617
DOI: 10.3389/fendo.2016.00128 -
Molecules (Basel, Switzerland) May 2024-Tetrahexylporphyrin was converted to its corresponding 7,8-dihydroxychlorin using an osmium tetroxide-mediated dihydroxylation strategy. Its diol moiety was shown to be...
-Tetrahexylporphyrin was converted to its corresponding 7,8-dihydroxychlorin using an osmium tetroxide-mediated dihydroxylation strategy. Its diol moiety was shown to be able to undergo a number of subsequent oxidation reactions to form a chlorin dione and porpholactone, the first -alkylporphyrin-based porphyrinoid containing a non-pyrrolic building block. Further, the diol chlorin was shown to be susceptible to dehydration, forming the porphyrin enol that is in equilibrium with its keto-chlorin form. The -hexylchlorin dione could be reduced and it underwent mono- and bis-methylation reactions using methyl-Grignard reagents, and trifluoromethylation using the Ruppert-Prakash reagent. The optical and spectroscopic properties of the products are discussed and contrasted to their corresponding -aryl derivatives (where known). This contribution establishes -tetrahexyl-7,8-dihydroxychlorins as a new and versatile class of chlorins that is susceptible to a broad range of conversions to generate functionalized chlorins and a pyrrole-modified chlorin analogue.
PubMed: 38731635
DOI: 10.3390/molecules29092144 -
Asian Biomedicine : Research, Reviews... Oct 2023Hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome is generally considered to be a variant or complication of preeclampsia. It is a life-threatening...
BACKGROUND
Hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome is generally considered to be a variant or complication of preeclampsia. It is a life-threatening obstetric complication.
OBJECTIVES
To evaluate the immunohistochemistry and ultrastructural of syncytiotrophoblastand Hoffbauer cells in placental villi of patients with HELLP syndrome.
METHODS
Two groups of patients with a total of 50 full-term human placentas (n = 25 in each group) were assigned as the control (normotensive) and HELLP syndrome. Placental tissue samples were fixed in 10% neutral formalin and paraffin-embedding protocol was performed. We prepared 5 μm sections for histological and immunohistochemical staining. Sections were immunostained with Hoffbauer cell marker CD68. For transmission electron microscopy (TEM), placental tissue samples were fixed in 2.5% buffered glutaraldehyde and then, in 1% osmium tetroxide for routine ultrastructural examinations.
RESULTS
When the HELLP group fetal placental sections were examined, intracytoplasmic edema in syncytiotrophoblast, degenerative vacuoles, and degenerative findings on cell surface membranes were observed. Moreover, villous edema was remarkable. The number of CD68-positive Hoffbauer cells per villus control group sections was 0.23 ± 0.02 and the number of CD68-positive cells per villus in HELLP group placenta sections was 0.83 ± 0.12. The increase in the number of Hoffbauer cells per villus in the HELLP group was significant ( < 0.001). Compared with the control group, there was a significant increase in the number of Hoffbauer cells and syncytiotrophoblasts in the HELLP group, and degenerative changes were also observed in the ultrastructure of these cells.
CONCLUSIONS
Pathology of the HELLP syndrome is in relation to CD68-positive placental macrophages.
PubMed: 37899759
DOI: 10.2478/abm-2023-0065 -
Foods (Basel, Switzerland) Apr 2020The aim of the research was to verify the necessity of secondary fixation with osmium tetroxide in various types of meat products and evaluation of structural changes of...
The aim of the research was to verify the necessity of secondary fixation with osmium tetroxide in various types of meat products and evaluation of structural changes of products using different fixation procedures. The material for the study consisted of 11 types of meat products that were analyzed using a scanning electron microscope (SEM) with two different methods of chemical fixation. The first method included the usual processing of biological samples: glutaraldehyde primary fixation, the use of a buffer, secondary fixation by osmium tetroxide (OsO), buffer, and dehydration using ethanol of increasing concentrations. The second method comprised the glutaraldehyde primary fixation and dehydration using the ethanol of increasing concentrations only. The results unambiguously suggest that the main difference between these methods is in fixation and visibility of fat. Our analysis principally suggests that fixation of the product with OsO allows the tracking of all components (fat droplets, muscle fibers, connective tissue) in meat products. At the same time, our results also support the possibility that the secondary fixation can be skipped during the analysis, where the main objection is an observation of lipid-free structures of the meat products (e.g., connection between muscle and starches or spices) or meat products with an insignificant amount of fat.
PubMed: 32295008
DOI: 10.3390/foods9040487