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Quiste Epidérmico , Granuloma , Tiña , Humanos , Tiña/microbiología , Tiña/tratamiento farmacológico , Granuloma/microbiología , Granuloma/patología , Quiste Epidérmico/patología , Quiste Epidérmico/microbiología , Masculino , Trichophyton/aislamiento & purificación , Antifúngicos/uso terapéutico , Biopsia , Microscopía Electrónica de Transmisión , Femenino , Resultado del Tratamiento , ArthrodermataceaeRESUMEN
Leafcutter ants are dominant herbivores in the Neotropics and rely on a fungus (Leucoagaricus gongylophorus) to transform freshly gathered leaves into a source of nourishment rather than consuming the vegetation directly. Here we report two virus-like particles that were isolated from L. gongylophorus and observed using transmission electron microscopy. RNA sequencing identified two +ssRNA mycovirus strains, Leucoagaricus gongylophorus tymo-like virus 1 (LgTlV1) and Leucoagaricus gongylophorus magoulivirus 1 (LgMV1). Genome annotation of LgTlV1 (7401 nt) showed conserved domains for methyltransferase, endopeptidase, viral RNA helicase, and RNA-dependent RNA polymerase (RdRp). The smaller genome of LgMV1 (2636 nt) contains one open reading frame encoding an RdRp. While we hypothesize these mycoviruses function as symbionts in leafcutter farming systems, further study will be needed to test whether they are mutualists, commensals, or parasites.
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Hormigas , Virus Fúngicos , Genoma Viral , ARN Viral , Virus Fúngicos/genética , Virus Fúngicos/clasificación , Virus Fúngicos/aislamiento & purificación , Virus Fúngicos/fisiología , Animales , Hormigas/microbiología , Hormigas/virología , ARN Viral/genética , Filogenia , Sistemas de Lectura Abierta , Simbiosis , ARN Polimerasa Dependiente del ARN/genética , Microscopía Electrónica de Transmisión , Virus ARN/genética , Virus ARN/clasificación , Virus ARN/aislamiento & purificación , Virus ARN/fisiología , Agaricales/virología , Agaricales/genéticaRESUMEN
Endocrine cells in the fundic stomach of Clarias gariepinus were characterized in this work using transmission electron microscopy, immunohistochemistry, and histochemistry. Performic acid mixed with alcian blue pH2.5 and silver stain were among the histochemical stains used for endocrine cells. Endocrine cells can be found in the epithelium, lamina propria, submucosa, muscular layer, serosa, and the area between the stomach glands. Endocrine cells with one or more nuclei were found. Endocrine cells were studied using CD3, CD21, and CD68 in an immunohistochemistry analysis. The expression of the lymphocyte marker CD3 by endocrine cells is remarkable. In addition, they had a strong immunological response to CD21 and CD68, which are characteristics of phagocytic cells. Granules of varied sizes and electron densities are packed densely into the cytoplasm of the cells, as seen by transmission electron microscopy. We propose that endocrine cells play a crucial role in immune defense. The role of endocrine cells in the gut's immune system is an area that needs further investigation.
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Bagres , Inmunohistoquímica , Microscopía Electrónica de Transmisión , Animales , Bagres/inmunología , Inmunohistoquímica/veterinaria , Microscopía Electrónica de Transmisión/veterinaria , Células Endocrinas/ultraestructura , Estómago/ultraestructura , Células Gigantes/ultraestructuraRESUMEN
Silver nanoparticles (AgNPs) have been successfully synthesized using leaf extract of Neem (Azadirachta Indica), Mint (Mentha Piperita), Tulsi (Ocimum Tenuiflorum), Bermuda grass (Cynodon Dactylon) and silver salt. As plant extracts produce best capping material for the stabilization of nanoparticles. AgNPs were characterized by UV-Vis spectroscopy in range of 200-800 nm and transmission electron microscopy TEM, XRD and FTIR. The nanoparticles synthesized were mainly in sizes between 25 and 100 nm. They appeared to be spherical, nanotriangles and irregular in shape. Catalytic application was observed for all the aqueous solution of leaves, quantity taken was 1 ml, 2 ml, 3 ml, 4 ml and 5 ml. Furthermore, prepared Ag nanoparticles are also used for seed germination.
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Germinación , Tecnología Química Verde , Nanopartículas del Metal , Extractos Vegetales , Semillas , Plata , Plata/química , Nanopartículas del Metal/química , Germinación/efectos de los fármacos , Catálisis , Tecnología Química Verde/métodos , Semillas/crecimiento & desarrollo , Semillas/química , Semillas/efectos de los fármacos , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Microscopía Electrónica de TransmisiónRESUMEN
OBJECTIVE: To develop a novel calcium silver zeolite (Ca-Ag-Zeo) and assess its biocompatibility, physiochemical properties and antimicrobial effects. METHODS: Ca-Ag-Zeo was synthesized using ion-exchange method with calcium chloride, silver nitrate and Zeolite X (Zeo). Silver zeolite X (Ag-Zeo) and Zeo were set as control. The chemical structure, morphology, crystal structure and elemental composition of Ca-Ag-Zeo was characterized by X-ray diffraction spectrum, scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy, respectively. Its biocompatibility on the human gingival fibroblasts was assessed by cell counting kit-8 assay. Its physiochemical properties were determined by the released calcium and silver ion using Inductive Coupled Plasma Emission Spectrometry for up to 12 weeks. The antimicrobial properties on Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus casei, and Candida albicans were assessed by minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC) assay. RESULTS: Ca-Ag-Zeo with a hexagonal cage structure was synthesized. As for biocompatibility, the half-maximal inhibitory concentration (± SD in mg/mL) of Ca-Ag-Zeo, Ag-Zeo and Zeo in human gingival fibroblasts were 0.52 ± 0.05, 0.15 ± 0.01 and 3.35 ± 0.58, respectively (Zeo > Ca-Ag-Zeo > Ag-Zeo; p < 0.05). As for physiochemical properties, the accumulated ion release (± SD in mg) of Ca-Ag-Zeo, Ag-Zeo and Zeo were 0.011 ± 0.003, 0 and 0 for calcium ion, respectively (Ca-Ag-Zeo > Ag-Zeo, Zeo; p < 0.001), and 0.213 ± 0.032, 0.209 ± 0.019 and 0 for silver ion, respectively (Ca-Ag-Zeo, Ag-Zeo > Zeo; p < 0.001). As for anti-microbial ability, the MBC/MFC (mg/mL) of Ca-Ag-Zeo, Ag-Zeo and Zeo were 32, 16 and > 256 against Streptococcus mutans; 32, 16, > 256 against Lactobacillus acidophilus; 16, 16, and 256 against Lactobacillus casei; 0.25, 0.125; and 2, 1, > 256 against Candida albicans, respectively. CONCLUSION: A novel Ca-Ag-Zeo was developed. It presented better biocompatibility compared to Ag-Zeo. It released calcium and silver ions sustainably, and it could inhibit the growth of common cariogenic microorganisms.
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Calcio , Candida albicans , Caries Dental , Fibroblastos , Pruebas de Sensibilidad Microbiana , Plata , Streptococcus mutans , Zeolitas , Humanos , Zeolitas/farmacología , Zeolitas/química , Streptococcus mutans/efectos de los fármacos , Candida albicans/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Caries Dental/prevención & control , Caries Dental/microbiología , Plata/farmacología , Plata/química , Lactobacillus acidophilus/efectos de los fármacos , Difracción de Rayos X , Encía/efectos de los fármacos , Encía/citología , Lacticaseibacillus casei/efectos de los fármacos , Microscopía Electrónica de Rastreo , Materiales Biocompatibles/farmacología , Microscopía Electrónica de Transmisión , Ensayo de Materiales , Nitrato de Plata/farmacología , Antibacterianos/farmacología , Antiinfecciosos/farmacologíaRESUMEN
BACKGROUND: The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) strains resistant to non-beta-lactam antimicrobials poses a significant challenge in treating severe MRSA bloodstream infections. This study explores resistance development and mechanisms in MRSA isolates, especially after the first dalbavancin-resistant MRSA strain in our hospital in 2016. METHODS: This study investigated 55 MRSA bloodstream isolates (02/2015-02/2021) from the University Hospital of the Medical University of Vienna, Austria. The MICs of dalbavancin, linezolid, and daptomycin were assessed. Two isolates (16-33 and 19-362) resistant to dalbavancin were analyzed via whole-genome sequencing, with morphology evaluated using transmission electron microscopy (TEM). RESULTS: S.aureus BSI strain 19-362 had two novel missense mutations (p.I515M and p.A606D) in the pbp2 gene. Isolate 16-33 had a 534 bp deletion in the DHH domain of GdpP and a SNV in pbp2 (p.G146R). Both strains had mutations in the rpoB gene, but at different positions. TEM revealed significantly thicker cell walls in 16-33 (p < 0.05) compared to 19-362 and dalbavancin-susceptible strains. None of the MRSA isolates showed resistance to linezolid or daptomycin. CONCLUSION: In light of increasing vancomycin resistance reports, continuous surveillance is essential to comprehend the molecular mechanisms of resistance in alternative MRSA treatment options. In this work, two novel missense mutations (p.I515M and p.A606D) in the pbp2 gene were newly identified as possible causes of dalbavancin resistance.
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Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Infecciones Estafilocócicas , Teicoplanina , Secuenciación Completa del Genoma , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Austria/epidemiología , Antibacterianos/farmacología , Teicoplanina/farmacología , Teicoplanina/análogos & derivados , Infecciones Estafilocócicas/microbiología , Daptomicina/farmacología , Mutación , Linezolid/farmacología , Masculino , Mutación Missense , FemeninoRESUMEN
Background: Non-steroidal anti-inflammatory drugs (NSAIDs), such as diclofenac (DCF), form a significant group of environmental contaminants. When the toxic effects of DCF on plants are analyzed, authors often focus on photosynthesis, while mitochondrial respiration is usually overlooked. Therefore, an in vivo investigation of plant mitochondria functioning under DCF treatment is needed. In the present work, we decided to use the green alga Chlamydomonas reinhardtii as a model organism. Methods: Synchronous cultures of Chlamydomonas reinhardtii strain CC-1690 were treated with DCF at a concentration of 135.5 mg × L-1, corresponding to the toxicological value EC50/24. To assess the effects of short-term exposure to DCF on mitochondrial activity, oxygen consumption rate, mitochondrial membrane potential (MMP) and mitochondrial reactive oxygen species (mtROS) production were analyzed. To inhibit cytochrome c oxidase or alternative oxidase activity, potassium cyanide (KCN) or salicylhydroxamic acid (SHAM) were used, respectively. Moreover, the cell's structure organization was analyzed using confocal microscopy and transmission electron microscopy. Results: The results indicate that short-term exposure to DCF leads to an increase in oxygen consumption rate, accompanied by low MMP and reduced mtROS production by the cells in the treated populations as compared to control ones. These observations suggest an uncoupling of oxidative phosphorylation due to the disruption of mitochondrial membranes, which is consistent with the malformations in mitochondrial structures observed in electron micrographs, such as elongation, irregular forms, and degraded cristae, potentially indicating mitochondrial swelling or hyper-fission. The assumption about non-specific DCF action is further supported by comparing mitochondrial parameters in DCF-treated cells to the same parameters in cells treated with selective respiratory inhibitors: no similarities were found between the experimental variants. Conclusions: The results obtained in this work suggest that DCF strongly affects cells that experience mild metabolic or developmental disorders, not revealed under control conditions, while more vital cells are affected only slightly, as it was already indicated in literature. In the cells suffering from DCF treatment, the drug influence on mitochondria functioning in a non-specific way, destroying the structure of mitochondrial membranes. This primary effect probably led to the mitochondrial inner membrane permeability transition and the uncoupling of oxidative phosphorylation. It can be assumed that mitochondrial dysfunction is an important factor in DCF phytotoxicity. Because studies of the effects of NSAIDs on the functioning of plant mitochondria are relatively scarce, the present work is an important contribution to the elucidation of the mechanism of NSAID toxicity toward non-target plant organisms.
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Antiinflamatorios no Esteroideos , Chlamydomonas reinhardtii , Diclofenaco , Potencial de la Membrana Mitocondrial , Mitocondrias , Consumo de Oxígeno , Especies Reactivas de Oxígeno , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Diclofenaco/toxicidad , Chlamydomonas reinhardtii/efectos de los fármacos , Chlamydomonas reinhardtii/metabolismo , Chlamydomonas reinhardtii/ultraestructura , Antiinflamatorios no Esteroideos/toxicidad , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Cianuro de Potasio/toxicidad , Oxidorreductasas/metabolismo , Salicilamidas , Microscopía Electrónica de Transmisión , Proteínas de Plantas , Proteínas MitocondrialesRESUMEN
This study aimed to assess the ecological risks posed by sulfamethoxazole (SMX) at environmentally relevant concentrations. Specifically, its effects on the growth and biochemical components (total protein, total lipid, and total carbohydrate) of two marine microalgae species, namely Skeletonema costatum (S. costatum) and Phaeodactylum tricornutum (P. tricornutum), were investigated. Our findings revealed that concentrations of SMX below 150â¯ng/L stimulated the growth of both microalgae. Conversely, at higher concentrations, SMX inhibited their growth while promoting the synthesis of photosynthetic pigments, total protein, total lipid, and total carbohydrate (P < 0.05). Transmission electron microscope (TEM) observations demonstrated significant alterations in the ultrastructure of algal cells exposed to SMX, including nuclear marginalization, increased chloroplast volume, and heightened vacuolation. In addition, when SMX was lower than 250â¯ng/L, there was no oxidative damage in two microalgae cells. However, when SMX was higher than 250â¯ng/L, the antioxidant defense system of algal cells was activated to varying degrees, and the level of malondialdehyde (MDA) increased, indicating that algae cells were damaged by oxidation. From the molecular level, environmental concentration of SMX can induce microalgae cells to produce more energy substances, but there are almost no other adverse effects, indicating that the low level of SMX at the actual exposure level was unlikely to threaten P. tricornutum, but a higher concentration can significantly reduce its genetic products, which can affect the changes of its cell structure and damage P. tricornutum to some extent. Therefore, environmental concentration of SMX still has certain potential risks to microalgae. These outcomes improved current understanding of the potential ecological risks associated with SMX in marine environments.
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Diatomeas , Microalgas , Estrés Oxidativo , Sulfametoxazol , Contaminantes Químicos del Agua , Sulfametoxazol/toxicidad , Diatomeas/efectos de los fármacos , Diatomeas/ultraestructura , Estrés Oxidativo/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Microalgas/efectos de los fármacos , Microalgas/ultraestructura , Transcriptoma/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Malondialdehído/metabolismo , Microscopía Electrónica de TransmisiónRESUMEN
Water vapor condensation on hygroscopic aerosol particles plays an important role in cloud formation, climate change, secondary aerosol formation, and aerosol aging. Conventional understanding considers deliquescence of nanosized hygroscopic aerosol particles a nearly instantaneous solid to liquid phase transition. However, the nanoscale dynamics of water condensation and aerosol particle dissolution prior to and during deliquescence remain obscure due to a lack of high spatial and temporal resolution single particle measurements. Here we use real time in situ transmission electron microscopy (TEM) imaging of individual sodium chloride (NaCl) nanoparticles to demonstrate that water adsorption and aerosol particle dissolution prior to and during deliquescence is a multistep dynamic process. Water condensation and aerosol particle dissolution was investigated for lab generated NaCl aerosols and found to occur in three distinct stages as a function of increasing relative humidity (RH). First, a < 100 nm water layer adsorbed on the NaCl cubes and caused sharp corners to dissolve and truncate. The water layer grew to several hundred nanometers with increasing RH and was rapidly saturated with solute, as evidenced by halting of particle dissolution. Adjacent cube corners displayed second-scale curvature fluctuations with no net particle dissolution or water layer thickness change. We propose that droplet solute concentration fluctuations drove NaCl transport from regions of high local curvature to regions of low curvature. Finally, we observed coexistence of a liquid water droplet and aerosol particle immediately prior to deliquescence. Particles dissolved discretely along single crystallographic directions, separated by few second lag times with no dissolution. This work demonstrates that deliquescence of simple pure salt particles with sizes in the range of 100 nm to several microns is not an instantaneous phase transition and instead involves a range of complex dissolution and water condensation dynamics.
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Aerosoles , Microscopía Electrónica de Transmisión , Nanopartículas , Cloruro de Sodio , Nanopartículas/química , Cloruro de Sodio/química , Tamaño de la PartículaRESUMEN
Background: Telocytes are interstitial stromal cells identified in various human organs, including the kidney. Their presence and role in human diabetic kidney disease remain unknown. Methods: To identify and localize telocytes in glomerular and tubule-interstitial compartments, both normal and diabetic human renal tissues were examined using immunohistochemistry, immunofluorescence, and transmission electron microscopy. Results: Renal telocytes are elongated interstitial cells with long, thin telopodes, showing alternating thin and thick segments. They expressed CD34, Nestin, α-SMA, and Vimentin markers. Occasionally, c-Kit expression was observed in some rounded and spindle cells, while no positivity was detected for PDGFR-ß and NG2. Telocytes were identified around Bowman's capsule, tubules, and peritubular capillaries in both normal and diabetic conditions. In diabetic renal samples, there was a significant increase in α-SMA expressing telocytes, leading to periglomerular fibrosis. These telocytes also exhibited a synthetic phenotype with proteoglycan deposition in the extracellular matrix and, in some cases, showed pre-adipocytic differentiation. Conclusions: Telocytes were identified in normal and diabetic human kidneys. These cells form an elastic mechanical scaffold in the interstitium and are present in all renal cortical compartments. In diabetic samples, their increased α-SMA expression and synthetic phenotype suggest their potential role in the pathogenesis of diabetic nephropathy.
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Antígenos CD34 , Nefropatías Diabéticas , Telocitos , Vimentina , Humanos , Telocitos/metabolismo , Telocitos/patología , Telocitos/ultraestructura , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/metabolismo , Antígenos CD34/metabolismo , Vimentina/metabolismo , Riñón/metabolismo , Riñón/patología , Inmunohistoquímica , Actinas/metabolismo , Nestina/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Masculino , Persona de Mediana Edad , Femenino , Microscopía Electrónica de Transmisión , AncianoRESUMEN
MAIN CONCLUSION: The ultrastructural design and biochemical organization of the significantly thickened outer tissues of the gametophytic stem of Hypnodendron menziesii optimizes load bearing of the stem. Hypnodendron menziesii is a bryoid umbrella moss growing in high humid conditions on the forest floors of New Zealand. The erect gametophyte bears up to eight whorls of branches in succession, spreading across the stem that bears the heavy weight of branches with highly hydrated leaves. Our investigation using a combination of light microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and TEM-immunolabeling techniques provided novel information on the structural design and biochemical organization of greatly thickened cell walls of epidermal, hypodermal, and outermost cortical tissues, comparing underlying thin-walled cortical tissues in the gametophytic stem. Probing into the ultrastructure of the cell wall architecture of these target tissues by TEM and SEM revealed the cell walls to display a multilamellar organization, in addition to demonstrating the presence of an electron-dense substance in the cell wall, presumably flavonoids. The pattern of distribution and concentration of rhamnogalacturonan, homogalacturonan, and heteromannan, as determined by immunogold labeling, suggests that it is the combination of structural and molecular design of the cell wall that may optimize the mechanical function of the epidermal, hypodermal, and outer cortical tissues. Statistical relationships between the overall thickness of epidermal, hypodermal, and outer cortical cell walls, the lumen area of cells and the percentage area of cell wall occupied in these tissues at different heights of the stem, and thickness of secondary cell wall layers (L1-L4/5) were explored. The results of these analyses unequivocally support the contribution of outer tissues to the mechanical strength of the resilient stem.
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Pared Celular , Tallos de la Planta , Pared Celular/ultraestructura , Tallos de la Planta/ultraestructura , Microscopía Electrónica de Rastreo , Células Germinativas de las Plantas/ultraestructura , Bryopsida/ultraestructura , Microscopía Electrónica de TransmisiónRESUMEN
PURPOSE: To compare the pathological characteristics of the vitreomacular interface of the idiopathic epiretinal membrane with and without disorganization of retinal inner layers (DRIL) and to correlate with clinical data. METHODS: In this clinicopathologic study, the samples of epiretinal membrane and internal limiting membrane were extracted from DRIL(+) (19 eyes) and DRIL(-) (22 eyes) idiopathic epiretinal membrane eyes. Ultrathin series sectioning for transmission electron microscopy was observed and correlated with surgery status and prognosis. RESULTS: All idiopathic epiretinal membrane eyes presented fibrocellular membranes accompanied by vitreous collagen, glial cells, and myofibroblasts, regardless of association with DRIL. A robust signal indicative of Collagen Type VI was observed in eyes DRIL(-), whereas Collagen Type I was discovered in DRIL eyes. Cell debris and microvascular basement membrane were seen on the retinal side of DRIL eyes and a larger cell count on the vitreous side. These have more intraoperative complications and less surgery benefit. CONCLUSION: Although internal limiting membrane peeling seems important, the histopathologic findings underscore the potential for retinal injury in DRIL(+) idiopathic epiretinal membrane eyes. This suggests that further research is needed to investigate individual preoperative assessment and to modify surgical procedures.
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Membrana Epirretinal , Vitrectomía , Cuerpo Vítreo , Humanos , Membrana Epirretinal/cirugía , Membrana Epirretinal/metabolismo , Membrana Epirretinal/diagnóstico , Membrana Epirretinal/patología , Anciano , Masculino , Femenino , Cuerpo Vítreo/patología , Cuerpo Vítreo/metabolismo , Persona de Mediana Edad , Microscopía Electrónica de Transmisión , Membrana Basal/patología , Membrana Basal/cirugía , Membrana Basal/metabolismo , Anciano de 80 o más Años , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Mácula Lútea/patología , Retina/patologíaRESUMEN
Over half of patients with heart failure have a preserved ejection fraction (>50%, called HFpEF), a syndrome with substantial morbidity/mortality and few effective therapies1. Its dominant comorbidity is now obesity, which worsens disease and prognosis1-3. Myocardial data from patients with morbid obesity and HFpEF show depressed myocyte calcium-stimulated tension4 and disrupted gene expression of mitochondrial and lipid metabolic pathways5,6, abnormalities shared by human HF with a reduced EF but less so in HFpEF without severe obesity. The impact of severe obesity on human HFpEF myocardial ultrastructure remains unexplored. Here we assessed the myocardial ultrastructure in septal biopsies from patients with HFpEF using transmission electron microscopy. We observed sarcomere disruption and sarcolysis, mitochondrial swelling with cristae separation and dissolution and lipid droplet accumulation that was more prominent in the most obese patients with HFpEF and not dependent on comorbid diabetes. Myocardial proteomics revealed associated reduction in fatty acid uptake, processing and oxidation and mitochondrial respiration proteins, particularly in very obese patients with HFpEF.
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Insuficiencia Cardíaca , Mitocondrias Cardíacas , Miocardio , Volumen Sistólico , Humanos , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/metabolismo , Masculino , Femenino , Anciano , Persona de Mediana Edad , Miocardio/patología , Miocardio/metabolismo , Miocardio/ultraestructura , Mitocondrias Cardíacas/ultraestructura , Mitocondrias Cardíacas/patología , Mitocondrias Cardíacas/metabolismo , Microscopía Electrónica de Transmisión , Función Ventricular Izquierda/fisiología , Sarcómeros/ultraestructura , Sarcómeros/metabolismo , Sarcómeros/patología , Biopsia , Proteómica , Obesidad/patología , Obesidad/metabolismo , Gotas Lipídicas/metabolismo , ComorbilidadRESUMEN
OBJECTIVE: Ex vivo skin has been used to study various skin conditions from atopic dermatitis to burn injury. The aim of this research is to identify a more effective barrier improvement strategy and to evaluate topical formulations in replenishing the skin. The skin can create new longer chain fatty acids and ceramides (CERs) from topically applied skin natural fatty acid to help renew the skin's barrier. METHODS: An ex vivo skin model damaged by sequential tape stripping of the stratum corneum (SC) was used to investigate the repair of the SC. Confocal laser scanning microscopy was used to assess the SC layers recovered. Ultrastructural analysis was performed using transmission electron microscopy to visualize the lamellar bodies and intercellular lipid lamellae. RESULTS: The data in this study provide the first direct ex vivo evidence comparing different marketed formulations containing three CERs with those containing fatty acids. Free fatty acid (FFA)-containing formulations, but not CER-containing formulations, directly applied to the damaged skin, showed an increased number of repaired SC layers and this was reflected at the ultrastructural level by an increased intercellular lipid lamellae length and an increased number of lamellar bodies. CONCLUSION: These findings demonstrate that FFA-containing formulations can repair damaged ex vivo skin and point to a repair mechanism in which topically applied palmitic and stearic acids, (which boost lipid levels and elongation) can increase the production and transport of lipids into a repaired SC and thus rebuild an effective skin barrier.
OBJECTIF: La peau ex vivo a été utilisée pour étudier diverses affections cutanées, allant de la dermatite atopique aux brûlures. L'objectif de cette étude est d'identifier une stratégie d'amélioration de la barrière cutanée plus efficace et d'évaluer les formulations topiques pour reconstituer la peau. La peau peut créer de nouveaux acides gras à chaîne plus longue et des céramides (CER) à partir d'acides gras naturels de la peau appliqués par voie topique pour aider à renouveler la barrière cutanée. MÉTHODES: Un modèle de peau ex vivo endommagé par un décapage séquentiel de la couche cornée a été utilisé pour étudier la réparation de la couche cornée. La microscopie confocale à balayage laser a été utilisée pour évaluer les couches de la couche cornée récupérées. Une analyse ultrastructurale a été réalisée par microscopie électronique à transmission pour visualiser les corps lamellaires et les lamelles lipidiques intercellulaires. RÉSULTATS: Les données de cette étude fournissent les premières preuves directes ex vivo comparant différentes formulations commercialisées contenant trois CER avec celles contenant des acides gras. Les formulations contenant des acides gras libres (AGL), mais pas celles contenant des CER, appliquées directement sur la peau endommagée, ont montré un nombre accru de couches de la couche cornée réparées, ce qui s'est traduit au niveau ultrastructural par une augmentation de la longueur des lamelles lipidiques intercellulaires et une augmentation du nombre de corps lamellaires. CONCLUSION: Ces résultats démontrent que les formulations contenant des AGL peuvent réparer la peau ex vivo endommagée et indiquent un mécanisme de réparation dans lequel les acides palmitique et stéarique appliqués par voie topique (qui stimulent les taux de lipides et leur allongement) peuvent augmenter la production et le transport de lipides dans une couche cornée réparée et ainsi reconstruire une barrière cutanée efficace.
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Ácidos Grasos , Piel , Piel/metabolismo , Piel/efectos de los fármacos , Administración Tópica , Humanos , Microscopía Confocal , Microscopía Electrónica de TransmisiónRESUMEN
INTRODUCTION: The integrity of the stratum corneum (SC) is crucial for the skin's barrier function, protecting against environmental stressors and minimizing transepidermal water loss. Advances in skincare formulations have introduced multilamellar systems designed to emulate the SC's lipid composition and organization. This study hypothesizes that the application of a multilamellar cream will significantly impact the SC's lipid content and lamellar structure, thereby enhancing the epidermal barrier. METHODS: A saturated phosphatidylcholine-based multilamellar cream was applied to a cohort of adult subjects with very dry skin. Electron microscopy was utilized to analyse the micro-morphology of the cream and its integration into the lipid-depleted SC. Lipid analysis was conducted to quantify changes in the intercellular lipid matrix. RESULTS: Transmission-electron microscopy (TEM) imaging demonstrated that the multilamellar cream possesses a structured arrangement comparable to the natural SC architecture. Short-term application revealed a time-dependent restoration of lipid bilayers, while a 14-day regimen showed a marked increase in lipid lamellae density and length within the SC. Lipid analysis indicated a significant increase in total lipid content, with notable enhancements in ceramide and free fatty acid levels, without altering cholesterol levels. Lipid ratio analysis further confirmed the rebalancing of the SC's lipid composition. DISCUSSION: The multilamellar cream selectively increased specific lipids critical for barrier function, suggesting an action mechanism that aligns with the skin's natural regulatory processes. This selective augmentation indicates the potential of the formulation to not only restore but also enhance the epidermal barrier, with the maintenance of physiological lipid ratios suggesting compatibility with intrinsic repair mechanisms. CONCLUSION: The study confirms that a multilamellar cream can significantly improve the SC's lipid composition and structural integrity, indicating enhanced barrier function. They are pivotal for skincare professionals, dermatologists, and product developers, enriching the understanding of multilamellar creams' benefits and applications in improving epidermal barrier function.
INTRODUCTION: l'intégrité de la couche cornée (SC, stratum corneum) est essentielle pour la fonction de barrière cutanée, protégeant contre les facteurs de stress environnementaux et réduisant au minimum la perte d'eau transépidermique. Les progrès en matière de formulations pour soins de la peau ont introduit des systèmes multilamellaires conçus pour simuler la composition et l'organisation lipidique du SC. Cette étude émet l'hypothèse que l'application d'une crème multilamellaire aura un impact significatif sur la teneur en lipides et la structure lamellaire du SC, améliorant ainsi la barrière épidermique. MÉTHODES: Une crème multilamellaire à base de phosphatidylcholine saturée a été appliquée à une cohorte de sujets adultes présentant une peau très sèche. La microscopie électronique a été utilisée pour analyser la micromorphologie de la crème et son intégration dans le SC délipidé. Une analyse lipidique a été réalisée pour quantifier les changements dans la matrice lipidique intercellulaire. RÉSULTATS: l'imagerie par TEM a démontré que la crème multilamellaire possède un agencement structuré comparable à l'architecture naturelle du SC. L'application à court terme a révélé une restauration dépendante du temps des bicouches lipidiques, tandis qu'un schéma posologique de 14 jours a montré une augmentation marquée de la densité et de la longueur des lamelles lipidiques au sein du SC. L'analyse lipidique a indiqué une augmentation significative de la teneur lipidique totale, avec des améliorations notables des taux de céramide et d'acides gras libres, sans altérer les taux de cholestérol. L'analyse du rapport lipidique a confirmé le rééquilibrage de la composition lipidique du SC. DISCUSSION: la crème multilamellaire a augmenté de manière sélective les lipides spécifiques essentiels à la fonction de barrière, suggérant un mécanisme d'action qui s'aligne sur les processus de régulation naturels de la peau. Cette augmentation sélective indique le potentiel de la formulation non seulement à restaurer, mais également à améliorer la barrière épidermique, avec le maintien des rapports lipidiques physiologiques suggérant une compatibilité avec les mécanismes de réparation intrinsèques. CONCLUSION: l'étude confirme qu'une crème multilamellaire peut améliorer de manière significative la composition lipidique et l'intégrité structurelle du SC, ce qui indique une meilleure fonction de barrière. Ils sont essentiels pour les professionnels de la peau, les dermatologues et les développeurs de produits, et enrichissent la compréhension des bénéfices et des applications des crèmes multilamellaires dans l'amélioration de la fonction de la barrière épidermique.
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Epidermis , Lípidos , Humanos , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Adulto , Lípidos/química , Femenino , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Crema para la Piel/farmacología , Crema para la Piel/administración & dosificaciónRESUMEN
High-pressure freezing/freeze substitution has been used to preserve biological samples for ultrastructure study instead of chemical fixation. For most plant samples, the water content is too high and cannot be properly preserved during cryofixation. Additionally, the cell wall is a barrier that prevents the substitution of water with the resin. In this chapter, we will discuss modified high-pressure freezing and subsequent processing protocols based on our routinely used methodology for examining Arabidopsis seeds in transmission electron microscopy and electron tomography.
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Arabidopsis , Tomografía con Microscopio Electrónico , Semillas , Semillas/ultraestructura , Tomografía con Microscopio Electrónico/métodos , Arabidopsis/ultraestructura , Congelación , Frío , Presión , Microscopía Electrónica de Transmisión/métodos , Criopreservación/métodos , Substitución por Congelación/métodosRESUMEN
The present study investigated the effect of ivermectin and amitraz on the cellular architecture of vital organs of Rhipicephalus microplus. Adult female ticks were treated with lethal concentrations (LC95) of ivermectin and amitraz, and the ovaries, synganglion, and Gené's organ were processed 48 h post treatment. In both the treatment groups, the ultra-thin sections of ovary exhibited deformed oocytes, irregular plasmic membrane and chorion layer, extensive vacuolation in the cytoplasm mainly at periphery of the cell and oocyte-pedicel junction. Marked vacuolations in the cortex and neuropile region with significant structural disorganization of the neural fibers were common alterations observed in the synganglion of ticks exposed to ivermectin and amitraz. The tissue sections of Gené's organ revealed deformed tubular glands with severe loss of cellular limit of secretory epithelium and cytoplasmic vacuolations in the ivermectin treated ticks whereas, the alterations were comparatively less severe in amitraz exposed ticks. The cellular deformities in these vital organs probably impaired reproductive function, nerve signal transmission and metabolic activities and thus affected fecundity and survivability of the treated ticks. The findings suggested that the action of ivermectin and amitraz are not restricted to the nervous system of ticks, but also on other vital organs, ovary and Gené's organ affecting the oviposition. The study provided insights into the development of targeted interventions for tick control strategies.
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Ivermectina , Ovario , Rhipicephalus , Toluidinas , Animales , Ivermectina/farmacología , Femenino , Rhipicephalus/efectos de los fármacos , Toluidinas/farmacología , Ovario/efectos de los fármacos , Acaricidas/farmacología , Microscopía Electrónica de TransmisiónRESUMEN
Terrestrial dissolved organic matter (DOM) plays critical roles in many biotic and abiotic environmental reactions as well as in water treatment. Its structure is therefore of great interest. We examined dissolved Suwannee River Humic Acid (HA) to probe the potential participation of exceptionally strong, negative charge-assisted hydrogen bonds, (-)CAHB, in DOM cohesion and interaction with small weak acids using high performance size exclusion chromatography (HPSEC), transmission electron microscopy, zeta-pH curves, and pH drift experiments. The results support a previously proposed two-tier state of aggregation, in which tightly-knit primary particles (≤ â¼10 kDa) form larger secondary aggregates (up to micrometer in size). Evidence for (-)CAHB is gained through zeta potential changes and pH drift experiments. The primary particles interact with (-)CAHB-capable solutes (simple carboxylic acids and phosphate) but not (-)CAHB-incapable solutes. We identified disruption of intra-segmental and inter-molecular (-)CAHB leading to swelling and disaggregation, as well as formation of nouveau (-)CAHB with free groups on HA. The effects were solute-concentration dependent and greater at pH 5 than pH 6, consistent with CAHB theory. Phosphate induced the greatest shifts in the HPSEC molecular size distribution curves. The shifts were unaffected by prior stripping of innate polyvalent metals. We conclude that the (-)CAHB contributes to the cohesion of DOM, affecting its size and charge, and provides a means by which weak acid pollutants, nutrients, and natural compounds can interact with DOM. Such interactions have implications for the behavior of DOM in the environment, the fate and transport of anthropogenic pollutants, and the roles DOM play in water treatment technologies.
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Sustancias Húmicas , Enlace de Hidrógeno , Ríos , Ríos/química , Concentración de Iones de Hidrógeno , Cromatografía en Gel , Microscopía Electrónica de Transmisión , Compuestos Orgánicos/químicaRESUMEN
Although irregularly-shaped label-free microplastics (MPs) are predominantly distributed in the environment, non-destructive analysis of environmentally relevant MPs in organisms is still challenging. The purpose of the study is to suggest in vivo visual evidence of the uptake and effect of environmentally relevant MPs in organism. Transparent irregularly-shaped high-density polyethylene was selected as an environmentally relevant model MP and exposed to brine shrimp (Artemia franciscana). As a result, we suggest the application of SEM/EDX and coherent anti-Stokes Raman scattering (CARS) microspectroscopy as complementary tools to secure in vivo visual evidence of irregularly-shaped unlabeled MPs in living organisms without chemical digestion for biodistribution observations. Biological transmission electron microscopy also provides how ingested MPs physically affects the digestive tract in the brine shrimp which is rarely reported. In terms of environmental implications, this study would advance ecotoxicological research on microplastic pollution by providing a cutting-edge tool for investigating the bioavailability and ecotoxicity of environmentally relevant MPs in ecosystems.
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Artemia , Microplásticos , Contaminantes Químicos del Agua , Animales , Microplásticos/toxicidad , Artemia/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Polietileno/toxicidad , Polietileno/química , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/metabolismo , Espectrometría Raman , Microscopía Electrónica de TransmisiónRESUMEN
A surface-modified mesoporous silica nanoparticle containing dimercaprol monomers was created utilizing the sol-gel condensation process, using tetraethyl orthosilicate (TEOS) as the silica source and poloxamer as the structure directing agent. To accomplish this synthesis, 3-glycidoxypropyl triethoxysilane (GPTS, 20 mol%) was incorporated into the silica walls during the sol-gel condensation process, along with TEOS. Furthermore, dimercaprol (DM) monomers were incorporated onto silica surfaces by a ring-opening reaction between GPTS epoxy groups, and dimercaprol hydroxyl groups. The prepared dimercaprol-modified silica adsorbent (MSN-DT NPs) material has been studied using a variety of instruments, including XRD, FT-IR, N2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric (TG) analysis, and zeta potential analysis. The MSN-DT NPs material selectively adsorbs mercury ions, with a high adsorption amount of 125 mg/g and a removal capability of roughly ~ 90% from the original metal ion mixture comprising other competing metals such as Pb2+, Ni2+, Fe2+, and Zn2+. The MSN-DT NPs adsorbent shows recyclable qualities for up to five cycles when treated with an acidic aqueous solution (0.1 M HCl). As a result, the MSN-DT NPs adsorbent may be regenerated and reused up to five times without losing its adsorption effectiveness. The experimental findings showed that the MSN-DT NPs adsorbent may be employed to selectively remove hazardous Hg2+ ions from an aqueous solution.