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Aims: This study aims to comprehensively examine the surface morphology of fiber posts after undergoing various disinfection methods, utilizing scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Materials and Methods: Twenty-one fiber posts were randomly allocated into seven experimental groups, each consisting of three samples. The disinfection methods employed were as follows: GC - no disinfection treatment; GAL - immersion in 70% alcohol, following the manufacturer's recommended protocol; GHP - soaking in 2.5% sodium hypochlorite for a duration of 10 minutes; GCL - soaking in 2% chlorhexidine gluconate for a period of five minutes; GAC - 30-second etching with 35% phosphoric acid; GPH - soaking in 10% hydrogen peroxide for a duration of 20 minutes; and GSL - autoclave sterilization. Following the disinfection procedures, SEM was employed to scrutinize the surface topography of the posts, while EDX was utilized to identify the chemical elements present on the sample surfaces. Subsequently, a descriptive analysis was conducted on the SEM images and EDX data. Results: SEM analysis revealed that all groups exhibited regions with epoxy resin-coated fibers alongside sections with exposed glass fibers. Analysis of the EDX data indicated that there were no significant differences in the predominant chemical elements across the groups. Carbon (C) and oxygen (O) registered the highest peaks, followed by silicon (Si), zirconium (Zr), sodium (Na), aluminum (Al), and calcium (Ca). Conclusions: The disinfection methods under investigation did not induce substantial alterations in the surface morphology of the fiber posts.
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SUMMARY: Prior research on post-COVID-19 or long COVID primarily focused on the presence of SARS-CoV-2 mostly in symptomatic patients. This study aimed to investigate the persistence of SARS-CoV-2 after 1 year of asymptomatic or mild COVID-19. SARS-CoV-2 infected and control K18-hACE2 transgenic mice (n=25) were studied. Moderate and severe symptomatic subjects were sacrificed after eight days, while mild or asymptomatic mice were kept in BSL-III for twelve months. Analyses included general condition, histochemistry, immunohistochemistry, transmission electron microscopy, and qRT-PCR. Lungs from the twelve-month group showed thickening of alveolar walls, with some lungs exhibiting the recruitment of inflammatory cells, the presence of SARS- CoV-2 mRNA, immunopositivity for the SARS-CoV-2 spike protein, and TEM showed viruses (60-125 nm) within vesicles, indicating continued replication. Certain lung samples showed persistent SARS-CoV-2 presence in Club cells, endothelial cells, and macrophages. The eight-day group exhibited viral interstitial pneumonitis, SARS-CoV-2 immunopositivity, and mRNA. The eight-day hearts displayed viral mRNA, while the twelve-month hearts tested negative. Some asymptomatic twelve-month subjects presented reduced surfactant, basal membrane thickening, fibrosis, and mild autonomic nerve degeneration. In this study conducted on mice, findings indicate the potential for chronic persistence of SARS-CoV-2 in the lungs one year post initial mild or asymptomatic infection, which could suggest the possibility of recurrent episodes in similar human conditions. The observed thickening of alveolar walls and potential fibrotic areas in these mice may imply an increased risk of post-COVID fibrosis in humans. Furthermore, the presence of SARS-CoV-2-positive inflammatory cells in some asymptomatic murine cases could herald a progression toward ongoing inflammation and chronic lung disease in humans. Therefore, the necessity for further studies in human subjects and vigilant monitoring of high-risk human populations is underscored.
Investigaciones anteriores sobre COVID-19 o COVID prolongado se centraron principalmente en la presencia de SARS-CoV-2 principalmente en pacientes sintomáticos. Este estudio tuvo como objetivo investigar la persistencia del SARS-CoV-2 después de 1 año de COVID-19 asintomático o leve. Se estudiaron ratones transgénicos K18-hACE2 infectados con SARS-CoV-2 y de control (n=25). Los animales con síntomas moderados y graves se sacrificaron después de ocho días, mientras que los ratones con síntomas leves o asintomáticos se mantuvieron en BSL-III durante doce meses. Los análisis incluyeron estado general, histoquímica, inmunohistoquímica, microscopía electrónica de transmisión y qRT- PCR. Los pulmones del grupo de doce meses mostraron engrosamiento de las paredes alveolares, y algunos pulmones exhibieron reclutamiento de células inflamatorias, presencia de ARNm del SARS-CoV-2, inmunopositividad para la proteína de la espícula del SARS-CoV-2 y TEM mostró virus (60 -125 nm) dentro de las vesículas, lo que indica una replicación continua. Ciertas muestras de pulmón mostraron una presencia persistente de SARS- CoV-2 en exocrinocitos bronquiolares, células endoteliales y macrófagos. El grupo de ocho días presentó neumonitis intersticial viral, inmunopositividad al SARS-CoV-2 y ARNm. Los corazones de ocho días mostraron ARNm viral, mientras que los corazones de doce meses dieron negativo. Algunos animales asintomáticos de doce meses presentaron disminución del surfactante, engrosamiento de la membrana basal, fibrosis y degeneración leve del nervio autónomo. En este estudio realizado en ratones, los hallazgos indican la posibilidad de persistencia crónica del SARS-CoV-2 en los pulmones un año después de la infección inicial leve o asintomática, lo que podría sugerir la posibilidad de episodios recurrentes en condiciones humanas similares. El engrosamiento observado de las paredes alveolares y las posibles áreas fibróticas en estos ratones puede implicar un mayor riesgo de fibrosis post-COVID en humanos. Además, la presencia de células inflamatorias positivas para SARS- CoV-2 en algunos casos murinos asintomáticos podría presagiar una progresión hacia una inflamación continua y una enfermedad pulmonar crónica en humanos. Por lo tanto, se subraya la necesidad de realizar más estudios en seres humanos y realizar un seguimiento atento de las poblaciones humanas de alto riesgo.
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Animals , Mice , Asymptomatic Infections , COVID-19/pathology , Lung/pathology , Pulmonary Fibrosis/pathology , RNA, Messenger , RNA, Viral/analysis , Immunohistochemistry , Mice, Transgenic , Weight Loss , Microscopy, Electron, Transmission , Real-Time Polymerase Chain Reaction , SARS-CoV-2/isolation & purification , COVID-19/virology , Post-Acute COVID-19 Syndrome/pathology , Lung/ultrastructure , Lung/virologyABSTRACT
SUMMARY: This study evaluated the morphology of alpacas skin. Biopsies were collected and samples were fixed in 10 % neutral buffered formalin for histological procedures. The sections were stained with hematoxylin and eosin, picrosirius red and Masson's trichrome. Types I, III and IV collagen were analyzed by immunohistochemistry. The derma presented sebaceous and sweat glands, as well as follicular groups with medullated fibers. Type I and type IV collagen were observed at epidermis and dermis as well as in glandular structures and hair follicles. The collagen III, was observed only in dermis.
Este estudio evaluó la morfología de la piel de alpacas. Se recogieron biopsias y las muestras se fijaron en formalina tamponada neutra al 10 % para procedimientos histológicos. Las secciones se tiñeron con hematoxilina y eosina, rojo picrosirius y tricrómico de Masson. El colágeno tipo I, III y IV se analizó mediante inmunohistoquímica. La dermis presentó glándulas sebáceas y sudoríparas, así como grupos foliculares con fibras medulares. Se observó colágeno tipo I y tipo IV en la epidermis y la dermis, así como en estructuras glandulares y folículos pilosos. El colágeno III, se observó únicamente en la dermis.
Subject(s)
Animals , Camelids, New World/anatomy & histology , Integumentary System/anatomy & histology , Immunohistochemistry , Microscopy, Electron, ScanningABSTRACT
Dental composite resins may release bisphenol-A or similar molecules affecting patient health and the environment. This study measured bisphenol-A release from three commonly used in patients composite resins (Filtek™ Z350 XT, Filtek™ P60, Filtek™ Bulk Fill) immersed in three liquid mediums (artificial saliva, 0.001 M lactic acid and 15% ethanol) and assessed the changes in the surface micromorphology.The released BPA was measured by HPLC at basal time (t=0), 1 h, 1 d, 7 d and 30 d. Topographic analysis of specimens was performed by scanning electron microscopy (SEM). The data were analyzed using one-way ANOVA and Tukey post-hoc test (P < 0.05). BPA in solution increased significantly in the three DCRs immersed in 0.001 M lactic acid at all times. SEM micrographs of the specimen in 0.001 M lactic acid disclosed more structural defects than others. The surface of the three composite resins was morphologically affected by their immersion in all solutions. SEM evidenced that the dental materials underwent erosion and cracks with filler particles protruding from the surface. The morphological changes in tested dental materials produced by exposure to these solutions are potentially dangerous to patients by causing caries, infections, and partial loss of dental material.
Subject(s)
Biomedical and Dental Materials , Bisphenol A-Glycidyl Methacrylate , Composite ResinsABSTRACT
Band 3 protein is an important channel protein in the erythrocyte membrane which mediates the anion transport process inside and outside the cell membrane,as well as contributes to the maintenance of erythrocyte morphology,and has important physiological functions.However,the distribution state of this protein in the primary cell membrane is not known.Cryo-scanning electron microscopy enables imaging of the surface morphology of biological samples in a near-physiological state.In order to investigate the distribution of band 3 protein on erythrocyte membranes under physiological conditions,the present study utilized 5-nm gold nanoparticles modified with the antibodies to specifically bind to the band 3 protein on human blood erythrocyte membranes and imaged them by cryo-scanning electron microscopy,to obtain distribution of band 3 protein on human blood erythrocyte membranes.The results showed that the membrane proteins on the erythrocyte membranes tended to be clustered and distributed to form ″protein islands″,and band 3 proteins were mainly distributed in these protein islands,which were tightly connected with each other to form several functional microregions to play their respective roles.
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BACKGROUND:As a dominant breed pig in southwest China,the southern Yunnan small-ear pig has been widely used as an experimental animal in the basic research of other disciplines,but there are still no reports on its application in anterior cruciate ligament reconstruction. OBJECTIVE:To establish a large animal model of the southern Yunnan small-ear pig with anterior cruciate ligament with autologous Achilles tendon was established. METHODS:Twenty adult female Yunnan small-ear pigs were equally randomized into two groups.In the autologous Achilles tendon group,the right knee anterior cruciate ligament was reconstructed with autologous Achilles tendon as a graft,while in the sham-operated group,a similar operation was performed on the right knee without any treatment of the anterior cruciate ligament.General conditions of each pig were observed and recorded before and 12 months after surgery.Ligaments and grafts were taken for gross observation and MAS scoring.Hematoxylin-eosin staining was performed to observe morphological characteristics of ligaments.The staining and arrangement of type I and type Ⅲ collagen were evaluated by immunohistochemistry.Transmission electron microscopy was used to observe the type,size,diameter,ratio,and distribution of collagen fibers in ligaments. RESULTS AND CONCLUSION:All animals had normal diet and activity,good wound healing,no obvious inflammatory reaction,no local purulent infection,and no significant changes in mental and urinary conditions compared with those before surgery.The reconstructed cruciate ligament of the knee was intact,with no stiffness and normal range of motion.Both the anterior drawer and Lachman tests were negative.Gross observation of the graft:12 months after surgery,the grafts was in good position,with good integrity,obvious tension,ligament color close to the original anterior cruciate ligament,and complete surface synovial coverage.Most of the intraarticular ligaments in the autologous Achilles tendon group were defined as MAS I type and a few were defined as MAS Ⅱ type.In the sham-operated group,the intraarticular ligament was defined as MAS I type.Hematoxylin-eosin staining indicated that,12 months after surgery,collagen fibers in the autologous Achilles tendon group began to appear bundled,isotropic,and uniformly arranged,with more obvious isotropic corrugations,and the nuclei were mainly linear or spindle-shaped,which were similar to those in normal anterior cruciate ligament tissue of the sham-operated group.Immunohistochemistry results indicated that,12 months after surgery,there was a higher expression of type I collagen and significantly less expression of type Ⅲ collagen in the reconstructed anterior cruciate ligament in the autologous Achilles tendon group.The degree of type I and type Ⅲ staining was similar in the two groups.Under the transmission electron microscope,the diameter,arrangement and density of collagen fibers in the reconstructed anterior cruciate ligament of the autologous Achilles tendon group were similar to those of the original anterior cruciate ligament at 12 months after surgery,indicating that the ligament remodeling process had been basically completed in the autologous Achilles tendon group at 12 months after surgery.Through a comprehensive evaluation of animal general conditions,ligament general view,MAS score,hematoxylin-eosin staining,immunohistochemistry,and transmission electron microscopy observation,we successfully established a large animal model of anterior cruciate ligament reconstruction using autogenous Achilles tendon in southern Yunnan small-ear pigs,with good morphological,histological and ultrastructural results.
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Objective@#To explore the effect of Morinda citrifolia juice (MCJ) combined with ethylene diamine tetraacetic acid (EDTA) on premolar bonding strength and nanoleakage and compare the results with those of the most commonly used root canal irrigation solution, sodium hypochlorite (NaClO), to provide a reference for clinical application.@*Methods@#This study was approved by the ethics review committee. Sixty-three human premolars extracted for orthodontic treatment were randomly divided into a control group (distilled water group) and 6 experimental groups according to the different rinsing solutions used after the surface enamel was removed. The experimental groups included Group A (2.5% NaClO), Group B (5.25% NaClO), Group C (6% MCJ), Group D (2.5% NaClO-17% EDTA), Group E (5.25% NaClO-17% EDTA), and Group F (6% MCJ-17% EDTA) (n = 9). After soaking in the corresponding rinsing solution for 20 minutes, they were layered and stacked on their surfaces to form 4 mm × 4 mm × 3 mm Z350 resin blocks. Six samples from each group were cut into 1 mm × 1 mm × 8 mm specimen strips for microtensile bonding strength testing. The fracture type was determined under a stereomicroscope, and the remaining 3 samples from each group were aged and cut into 1 mm thick slices for interface nanoleakage testing and scanning electron microscopy observation of the resin dentin bonding interface.@*Results@#There were significant differences in the microtensile bonding strength among the groups (P<0.05), and the control group had the highest bonding strength. Among experimental groups, Group B had the lowest bonding strength, mainly bonding interface fracture, and Group F had the highest bonding strength, mainly mixed fracture. There were significant differences in nanoleakage among all groups (P<0.05), and the control group had the lowest nanoleakage value. Among experimental groups, Group B had the highest nanoleakage, with resin protrusions being unaltered, and Group F had the lowest nanoleakage value, with resin protrusions being thick and dense.@*Conclusion@#The higher the concentration of NaClO was, the worse the bonding strength and edge sealing of the crown dentin were. The effects of root canal irrigation with MCJ and EDTA on the adhesive strength and edge sealing of crown dentin were less pronounced than those of root canal irrigation with NaClO and EDTA.
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ObjectiveTo explore the scientific connotation of fried charcoal survivability of Lonicerae Japonicae Flos（LJF） by analyzing the correlation between the color change and the intrinsic components during the processing of LJF Carbonisata（LJFC）， and taking pH， charcoal adsorption and microscopic characteristics as indexes. MethodLJFC samples with different degrees of processing were prepared according to the stir-frying time of 0.0， 1.5， 3.0， 4.5， 6.0， 7.5， 9.0， 10.5 min（numbered S1-S8）， and the contents of gallic acid， chlorogenic acid， cryptochlorogenic acid， rutin， luteoloside， isochlorogenic acid A and isochlorogenic acid C were determined by high performance liquid chromatography（HPLC）， and the L*（brightness）， a*（red-greenness） and b*（yellow-blueness） of LJFC samples with different degrees of processing were determined by spectrophotometer， and the correlation analysis and principal component analysis（PCA） between the contents of seven representative components and the color of the samples were carried out by SPSS 26. 0 and SIMCA-P 14.1. Then pH， adsorption force and characteristic structure of different samples of LJFC were detected and the processing pattern of LJFC was analyzed. ResultThe results of quantitative analysis revealed that the contents of luteoloside， rutin， chlorogenic acid and isochlorogenic acid A gradually decreased， and the contents of cryptochlorogenic acid， isochlorogenic acid C and gallic acid firstly increased and then decreased. The L* and b* of the sample powders decreased， and a* showed a trend of increasing and then decreasing. The L* and b* were positively correlated with the contents of chlorogenic acid， rutin， luteoloside， isochlorogenic acid A， b* was positively correlated with the content of gallic acid， and a* was positively correlated with the contents of cryptochlorogenic acid and isochlorogenic acid C. PCA revealed that samples could be clearly divided into 3 groups， S1-S2 as one group， S3-S5 as one group， and S6-S8 as one group， with S3 having the highest score. The results of regression analysis showed that only isochlorogenic acid C could be used to predict the contents of components by colorimetric values combined with regression equations. Physicochemical analysis showed that pH of LJFC increased with the increase of degree of charcoal stir-frying， while adsorption force showed a tendency of increasing and then decreasing， with the highest adsorption force in the S5 sample， and the non-glandular hairs， calcium oxalate clusters and pollen grains had a varying degree of decreasing with the deepening of processing degree， and the microstructures of S6-S8 samples were obviously charred with pollen grains almost invisible. ConclusionThe changes in chemical composition and color characteristics of LJFC during the processing have certain correlations， combined with the changes in physicochemical properties， S5 sample is found to be the optimal processed products， which can provide a reference for the processing standardization and quality evaluation of LJFC， and enrich the scientific connotation of fried charcoal survivability of LJF.
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The correct pairing of disulfide bonds maintains the correct folding mode and high-level structure formation of peptides and protein drugs, which is crucial for the quality control of products. In order to ensure that the disulfide bonds are correctly paired, disulfide bond analysis is an essential part of peptides and protein drug characterization. Mass spectrometry can be used to analyze disulfide bonds. However, insulin and its analogues have two pairs of disulfide bonds without restriction enzyme cutting site. Conventional collision-induced dissociation (CID) and high-energy induced cleavage (HCD) cannot accurately locate the complex disulfide bond. In our study, three methods were used to localize the complex disulfide, including enzyme digestion combined with key peptide fragment in source decay (ISD) fragmentation method, enzyme digestion combined with partial reduction alkylation method, intact protein source ISD and electron transfer dissociation (ETD) cleavage method, The applicability of insulin aspart, insulin lispro and insulin glargine were also investigated. This study provides a new way for the quality control of disulfide bonding mode of insulin and its analogues, and also provides a reference for the disulfide bond localization of peptides or proteins containing this complex disulfide bond.
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Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.
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Objective:To investigate the risk factors for recurrence of benign vocal cord lesions after microsurgery.Methods:The clinical data of 2 214 patients with benign vocal cord lesions who underwent laryngeal microsurgery at the Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Yangzhou University from April 2013 to April 2022 were collected. The data, including sex, age, drinking history, smoking history, unilateral and bilateral lesions, and diagnosis, were recorded. These patients were divided into six groups according to admission diagnosis: polyps, Reinke's edema, leukoplakia, granulomas, cysts, and other benign lesions. All patients were followed up for 0-115 months, with a median follow-up time of 55 months. The Kaplan-Meier curve was used to determine whether there was any difference in the recurrence rate of benign vocal cord lesions among groups after surgical treatment. The Cox regression model was used to analyze the risk factors for the recurrence of benign vocal cord lesions after surgical treatment.Results:Out of the 2 214 patients, there were 1 953 cases of polyps (88.21%), 41 cases of granulomas (1.85%), 67 cases of cysts (3.03%), 87 cases of leukoplakia (3.93%), 34 cases of Reinke's edema (1.54%), and 32 cases of other benign lesions (1.45%). The recurrence rate for benign vocal cord lesions was 4.86% (95/1 953) in the polyp group, 31.70% (13/41) in the granuloma group, 14.94% (13/87) in the leukoplakia group, 2.98% (2/67) in the cysts group, 8.82% (3/34) in the Reinke's edema group, and 9.37% (3/32) in the other benign lesions group. Univariate analysis showed that bilateral lesions (95% CI 6.899-17.289, P < 0.001), smoking history (95% CI 1.282-2.564, P = 0.001), and alcohol consumption (95% CI 1.173-2.346, P = 0.001) were significantly associated with the recurrence of benign vocal cord lesions. The recurrence rate for benign vocal cord lesions in the leukoplakia group (95% CI 1.375-27.011, P = 0.017) and granuloma group (95% CI 3.053-60.980, P = 0.001) was significantly higher than that in the cysts group. Multivariate analysis of the risk factors for postoperative recurrence of benign vocal cord lesions showed that patients who had bilateral lesions (95% CI 6.680-16.900, P < 0.001) and a history of smoking (95% CI 1.572-16.157, P = 0.007) had a higher risk of recurrence of benign vocal cord lesions compared with those without bilateral lesions and a history of smoking. Granulomas were found to be significantly associated with postoperative recurrence of benign vocal cord lesions (95% CI 4.691-97.667, P < 0.05). Conclusion:Bilateral lesions and smoking are independent risk factors for the recurrence of benign vocal cord lesions after microsurgery. Granuloma is strongly associated with the postoperative recurrence of benign vocal cord lesions.
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Objective:To calibrate the absorbed doses of the configured ray water with different gears of energies in accelerator based on<The use of plane-parallel ionization chambers in high-energy electron and photon beams>of International Atomic Energy Agency(IAEA)277 and 381 reports,so as to ensure the accuracy of the output dose of the linear accelerator during clinical radiotherapy.Methods:Elekta Infinity linear accelerator was used in this study,and the photon beam energies were respectively 6MV flattening filter(FF)mode and 6MV flattening filter free(FFF)mode.The electron beam energies were respectively 4,6,8,10,12 and 15MeV.According to the IAEA TRS277 and TRS381 reports,the calibrations of output doses in photon and electron beam waters were performed respectively by using the PTW dosimeter,PTW30013 finger type of ionization chamber and PTW34001 parallel plate ionization chamber.The error of each step was analyzed,and the accuracies of the calibrations of using different standards for the output waters of linear accelerator were compared.Results:The output amounts of photon beams of FF mode and FFF mode of 6MV at the maximum dose point in water were respectively 1.003 and 1.008cGy/MU.The output amounts of the energy of each gear of electron beams of 4,6,8,10,12 and 15MeV at the maximum dose point in water were respectively 1.003,1.002,0.998,0.999,1.000 and 1.003 cGy/MU.The calibration of the output of each gear of energy rays at the maximum dose point in water was 1cCy corresponded to 1MU,which error was less than 1%.Conclusion:The calibration for the output dose amount of accelerator in water on the basis of IAEA TRS277 and trs381 can ensure the accuracy of the output dose of the accelerator.
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The sample delivery method is one of the key steps in implementing serial femtosecond crystallography research using X-ray free-electron lasers. Serial femtosecond crystallography can effectively capture the ultrafast dynamic processes of biological molecules, such as protein conformational changes and intermediate states in chemical reactions. It is of great significance for scientists to better understand the structure and function of biological molecules, reveal the mechanisms of life activities, and provide important technical means for drug development and biotechnology. When conducting experiments at X-ray free-electron laser beamline station, it is crucial to transport the samples to the region where it interacts with the free-electron laser pulses. The choice of suitable sample delivery method plays a decisive role in the sample consumption and experimental efficiency, and it is also an important factor for the success or failure of the experiment. This article reviews the latest research progress and future development directions of sample delivery methods in serial crystallography. It also introduces commonly used sample delivery methods and their applicable ranges, aiming to provide reference and guidance for scientists engaged in serial crystallography research. The sample transport methods of free electron lasers mainly include liquid injection and fixed target sample transport. The liquid injection method is achieved through various liquid sample injectors. The aqueous solution is driven by a peristaltic pump on high performance liquid chromatography (HPLC) into a sample storage, and the aqueous solution pushes the piston in the sample storage to extrude the sample solution into the sample transport pipeline, and finally sprays it out through the nozzle to reach the XFEL interaction region. For micro-nano crystals,3 preparation methods are introduced, including free interface diffusion method, seeding method, and batch crystallization, and characterization methods are also introduced. For the requirements of high sample transmission efficiency and low sample consumption, a gas-based liquid flow transport method is introduced, which is based on the principle of focusing the sample jet by coaxial gas to form a jet with a small diameter and fast flow rate. At the same time, the extended double flow focusing nozzle and mixed injection nozzle are briefly described. For samples in viscous media, a high viscosity liquid injection device is introduced, and the advantages and disadvantages of different media are explained and exemplified. In addition, the principle and example of electrostatic spinning injector and piezoelectric driven droplet injection technology applied to low-velocity serial crystallography experiments are also introduced. For the above liquid injection methods, a characterization method using a coaxial microscope or side-view microscope to measure the diameter and stable length of the liquid flow is introduced. Compared with the liquid injection method, the fixed target method is to fix the crystal on a support chip with a periodic array structure, and collect data through scanning. The working principle, sample environment, support materials, etc. of the fixed target method are briefly introduced in the article. With the advancement and development of technologies such as free electron lasers and detectors, various sampling methods for serial crystallography are constantly being innovated and optimized. By selecting appropriate sample delivery methods, it will be possible to improve experimental efficiency, reduce sample consumption, and open up new possibilities for researchers in the field of structural biology of biomacromolecules.
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Abstract The present study aimed to investigate the beneficial of prepared black rice anthocyanins nano-composite (An-AgNps) against hepatotoxicity induced by methotrexate (MTX) in rats. Anthocyanins nano-composite was prepared by silver as the metallic ion reduction and were characterized by IR and SEM. The rats in our experiment were divided into five groups. Serum lipid profile, serum transaminases (ALT and AST), ALP, LDH, TBA, GSH and SOD were examined. The results show that SEM of An-AgNps has average particle size from 70 to 130nm. In the group treated with MTX; TC, TG, LDL-c, ALT, AST, ALP, LDH and TBA levels were significantly (P0.05) increased than NC, while, HDL-c, SOD and GSH levels were significantly (P0.05) decreased. On the other hand, An-AgNps + MTX treated groups were reversed the levels of all biomarkers similar to NC. In conclusion, the results show that An-AgNps has a protective effect on MTX-induced hepatotoxicity and oxidative stress.
Resumo O presente estudo teve como objetivo investigar o benefício de nanocompósito de antocianinas de arroz preto preparado (An-AgNps) contra a hepatotoxicidade induzida por metotrexato (MTX) em ratos. O nanocompósito de antocianinas foi preparado a partir da prata por meio da redução do íon metálico e caracterizado por IR e SEM. Os ratos em nosso experimento foram divididos em cinco grupos, e foram examinados o perfil lipídico sérico, as transaminases séricas (ALT e AST), ALP, LDH, TBA, GSH e SOD. Os resultados mostram que SEM de An-AgNps tem tamanho médio de partícula de 70 a 130 nm. No grupo tratado com MTX, os níveis de TC, TG, LDL-c, ALT, AST, ALP, LDH e TBA aumentaram significativamente (P 0,05) do que NC, enquanto os níveis de HDL-c, SOD e GSH diminuíram significativamente (P 0,05). Por outro lado, nos grupos tratados com An-AgNps + MTX, foram revertidos os níveis de todos os biomarcadores semelhantes ao NC. Em conclusão, os resultados mostram que o An-AgNps tem um efeito protetor contra a hepatotoxicidade induzida pelo MTX e o estresse oxidativo.
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Aim: To evaluate changes in the surface roughness and morphology of a nanofilled composite following toothbrushing with a whitening (WT) or regular toothpaste (RT), alone or combined with 35% hydrogen peroxide bleaching (HP). Methods: Seventy disc-shaped nanofilled composite (Filtek Z350XT) specimens were randomly divided into groups (n=10): WT, RT, TB (without toothpaste control) or the combinations WT/ HP, RT/HP, TB/HP and HP. All groups underwent toothbrushing simulation (60,000 cycles) and bleaching treatment (4 sessions). Mean surface roughness (Ra, µm) was measured before (T0) and after treatments (TB). Surface morphology was assessed by scanning electron microscopy (SEM) at TB. Mean Ra was analyzed using general mixed models and multiple comparisons by the Tukey-Kramer test (α=5%). Results: HP caused no surface roughness changes on the nanofilled composite after treatment (p>0.05). RT toothbrushing, combined or not with HP, increased the surface roughness (p<0.05). WT and WT/ HP protocols had no effect on the surface roughness of the composite (p>0.05). The nanofilled composite submitted to RT toothbrushing combined with HP (RT/HP) presented substantial surface alterations under SEM, showing deep depressions and round-shaped defects. Toothbrushing with RT combined with the bleaching agent increased exposure of the inorganic fillers. Conclusion: WT toothbrushing, regardless of HP combination, or the single HP protocol had no effect on the surface roughness of the nanofilled composite. However, RT combined with HP negatively affected surface roughness and presented the most noticeable surface changes among groups
Subject(s)
Tooth Bleaching , Toothpastes , Microscopy, Electron, Scanning , Composite Resins , Hydrogen PeroxideABSTRACT
Objective: The aim of this study was to determine if SEM used with imaging software could be used to quantitatively determine the extent of dentine roughness due to tooth-brushing. Material and methods: Flat, polished dentine surfaces were subjected to 25,000 cycles of simulated tooth-brushing at 2 strokes per second with a load of 200 g. At the end of the brushing cycle, dentine surfaces were first assessed using profilometry and then subjected to SEM analysis. Ra (average roughness) readings were obtained for profilometric assessment. Using imaging software, the horizontal distance between adjacent characteristic grooves noted on micrographs was measured, ensuring that the middle of each crest of the associated groove was used as the reference point, the Crest-to-Crest distance (C-C distance). These two parameters were examined statistically for correlation. Results: When Spearman Rank tests were utilized the correlation between average Ra and crest to crest measurements was 0.709 (p <0.01). The Bland Altman plot, however, showed poor agreement between the two test parameters. Conclusion: Further work is needed to validate the use of this methodology in the quantitative assessment of tooth surface loss due to abrasion (AU)
Objetivo: O objetivo deste estudo foi determinar se o MEV usado com software de imagem poderia ser usado para determinar quantitativamente a extensão da rugosidade da dentina devido à escovação dentária. Material e Métodos: Superfícies dentinárias planas e polidas foram submetidas a 25.000 ciclos de escovação dentária simulada a 2 movimentos por segundo com uma carga de 200g. No final do ciclo de escovação, as superfícies dentinárias foram primeiro avaliadas por perfilometria e depois submetidas à análise MEV. Leituras de Ra (rugosidade média) foram obtidas para avaliação perfilométrica. Utilizando um software de imagem, foi medida a distância horizontal entre sulcos característicos adjacentes observados nas micrografias, garantindo que o meio de cada crista do sulco associado fosse usado como ponto de referência, a distância crista a crista (distância CC). Esses dois parâmetros foram examinados estatisticamente para correlação. Resultados: Quando foram utilizados os testes de Spearman Rank, a correlação entre a média de Ra e as medidas de crista a crista foi de 0,709 (p<0,01). O gráfico de Bland Altman, no entanto, mostrou fraca concordância entre os dois parâmetros de teste. Conclusão: Mais trabalhos são necessários para validar o uso desta metodologia na avaliação quantitativa da perda da superfície dentária devido à abrasão(AU)
Subject(s)
Surface Properties , Tooth Abrasion , Toothbrushing , Microscopy, Electron, Scanning , DentinABSTRACT
Abstract This study compares the effects of virus-cell interactions among SARS-CoV-2 variants of concern (VOCs) isolated in Brazil in 2021, hypothesizing a correlation between cellular alterations and mortality and between viral load and transmissibility. For this purpose, reference isolates of Alpha, Gamma, Zeta, and Delta variants were inoculated into monolayers of Vero-E6 cells. Viral RNA was quantified in cell supernatants by RT‒PCR, and infected cells were analyzed by Transmission Electron Microscopy (TEM) for qualitative and quantitative evaluation of cellular changes 24, 48, and 72 hours postinfection (hpi). Ultrastructural analyses showed that all variants of SARS-CoV-2 altered the structure and function of mitochondria, nucleus, and rough endoplasmic reticulum of cells. Monolayers infected with the Delta variant showed the highest number of modified cells and the greatest statistically significant differences compared to those of other variants. Viral particles were observed in the cytosol and the cell membrane in 100 % of the cells at 48 hpi. Alpha showed the highest mean particle diameter (79 nm), and Gamma and Delta were the smallest (75 nm). Alpha and Gamma had the highest particle frequency per field at 48 hpi, while the same was observed for Zeta and Delta at 72 hpi and 24 hpi, respectively. The cycle threshold of viral RNA varied among the target protein, VOC, and time of infection. The findings presented here demonstrate that all four VOCs evaluated caused ultrastructural changes in Vero-E6 cells, which were more prominent when infection occured with the Delta variant.
ABSTRACT
BACKGROUND: Basal energetic metabolism in sperm, particularly oxidative phosphorylation, is known to condition not only their oocyte fertilising ability, but also the subsequent embryo development. While the molecular pathways underlying these events still need to be elucidated, reactive oxygen species (ROS) could have a relevant role. We, therefore, aimed to describe the mechanisms through which mitochondrial activity can influence the first stages of embryo development. RESULTS: We first show that embryo development is tightly influenced by both intracellular ROS and mitochondrial activity. In addition, we depict that the inhibition of mitochondrial activity dramatically decreases intracellular ROS levels. Finally, we also demonstrate that the inhibition of mitochondrial respiration positively influences sperm DNA integrity, most likely because of the depletion of intracellular ROS formation. CONCLUSION: Collectively, the data presented in this work reveals that impairment of early embryo development may result from the accumulation of sperm DNA damage caused by mitochondrial-derived ROS.
Subject(s)
Humans , Male , Semen/metabolism , Mitochondria , Spermatozoa/metabolism , Reactive Oxygen Species/metabolism , Oxidative Stress , Embryonic DevelopmentABSTRACT
Purpose: To evaluate, by quantitative and qualitative methods, the glomerular ultrastructure in Wistar rats fed a cafeteria diet. Methods: Male Wistar rats were divided into two groups at 21 days of age: control (C, n = 10) and cafeteria diet (CAF, n = 8). The animals were followed up until 5 months of age, followed by euthanasia. The blood, kidneys, and fat depositsepididymal, retroperitoneal, and subcutaneouswere extracted and analyzed. Data were analyzed by Student's t test, and p < 0.05 was considered statistically significant. Results: The cafeteria diet promoted glucose intolerance, hyperglycemia (p < 0.0001), and deposition of retroperitoneal fat (p < 0.005). Scanning electron microscopy revealed that the length of the foot process was similar in both groups. The quantitative analyses by transmission electron microscopy revealed that the cafeteria diet reduced the thickness of the glomerular basement membrane (p < 0.05). Conclusions: The intake of lipids and simple carbohydrates were found to be associated with alteration in the glomerular ultrastructure. However, more studies are needed to evaluate not only the effects of high-protein and high-fat diets on components of the glomerular filtration barrier, but also renal physiology.
Subject(s)
Animals , Rats , Microscopy, Electron, Scanning , Rats, Wistar , Diet , KidneyABSTRACT
The incorporation of different molecules by eukaryotic cells occurs through endocytosis, which is critical to the cell's survival and ability to reproduce. Although this process has been studied in greater detail in mammalian and yeast cells, several groups working with pathogenic protists have made relevant contributions. This review analysed the most relevant data on the endocytic process in anaerobic protists (Entamoeba histolytica, Giardia intestinalis, Trichomonas vaginalis, and Tritrichomonas foetus). Many protozoa can exert endocytic activity across their entire surface and do so with great intensity, as with E. histolytica. The available data on the endocytic pathway and the participation of PI-3 kinase, Rab, and Rho molecular complexes is reviewed from a historical perspective.