Opisthorchiasis-associated biliary stones:Light and scanning electron microscopic study

AIM:Biliary stones are frequently encountered in areas endemic for opisthorchiasis in Thailand.The present study was to describe the prevalence and pathogenesis of these stones. METHODS:Gallstones and/or common bile duct stones and bile specimens from 113 consecutive cholecystectomies were included.Bile samples,including sludge and/or microcalculi,were examined for Opisthorchis viverrinieggs, calcium and bilirubin.The stones were also processed for scanning electron microscopic(SEM)study. RESULTS:Of the 113 cases,82 had pigment stones,while one had cholesterol stones.The other 30 cases had no stones.Most of the stone cases(76%,63/83)had multiple stones,while the remainder had a single stone.Stones were more frequently observed in females.Bile examination was positive for O.viverrini eggs in 50% of the cases studied.Aggregates of calcium bilirubinate precipitates were observed in all cases with sludge.Deposition of calcium bilirubinate on the eggshell was visualized by special staining.A SEM study demonstrated the presence of the parasite eggs in the stones.Numerous crystals, morphologically consistent with calcium derivatives and cholesterol precipitates,were seen. CONCLUSION:Northeast Thailand has a high prevalence of pigment stones,as observed at the cholecystectomy,and liver fluke infestation seems involved in the pathogenesis of stone formation.

Neutron Activation Analysis and Scanning Electron Microscopy of Phytoplankton in the Coastal Zone of Crimea (The Black Sea)

The physiology and ecology of planktonic organisms are influenced by the concentration, chemical speciation and resulting bioavailability of some trace metals. The determination of the elemental structure of phytoplankton is important for interpretation of physiological and functional states of coastal ecosystems. The present study is focused on the structure and elemental composition of the phytoplankton assemblages from the different coastal zones by instrumental neutron activation analysis (INAA), scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDS). For the first time these complementary techniques were simultaneously applied to study the Black Sea phytoplankton. The concentrations of 45 elements in the coastal phytoplankton communities used as bioindicator of inorganic contamination of the Black Sea coastal area near Sevastopol, Ukraine, were determined. Phytoplankton samples were collected by total tows of the plankton net with 35 μm pore size at 3 stations situated in polluted and relatively pristine water areas of the Sevastopol coastal zone during autumn period of the phytoplankton growth. The concentration of Mg, Al, Sc, Ti, V, Mn, As, Rb, Ba, Th and Fe, Cr increases exponentially from relatively pristine station to more polluted station and 10-times and 3-times greater, respectively, in the phytoplankton of the Sevastopol Bay. The rare-earth elements have relatively the same concentration values less than 1 μg/g and tend to accumulate in the phytoplankton from the polluted station in the Sevastopol Bay. The obtained results are in a good agreement with the elemental concentration data in the oceanic plankton, plankton communities from the White Sea and the Black Sea. Using energy-dispersive X-ray spectrometry the mineral particles of unknown origin and impurities of copper (0.42% by weight) in the phytoplankton at the polluted station and zinc (0.57% by weight) at the relatively pristine station were determined.

OBSERVATION AND ANALYSIS OF BLOOD CONTACTING SURFACE OF LEFT VENTRICULAR ASSIST DEVICE WITH SCANNING ELECTRON MICROSCOPY

Thrombus formation in the artificial heart blood pump is a complex problem. The most important factor of thrombosis in the blood pump is the quality of blood contacting surface which is related to hemocompatibility of materials and micromorphololgy or roughness of the surface. So it is necessary to understand the morphology of the surface inside of blood pump in order to develop and improve a good quality blood pump. The authors observed and analysed the inner surface of blood pumps (both preimplanted and postimplanted) with scanning electron microscopy (SEM) providing a means for evaluating the blood pumps and for developing good quality of blood pumps. It was observed that there were four kinds of surface defects on the inner surface of the blood pumps: air bubble domes, open bubble craters, contaminated dust and gel particles. Microcrakes had also been found on the diaphragm of the postimplanted pump. But in the newly improved blood pump that had been imlanted for 16 days, there were few defects on the blood contacting surface, and only a little fibrinous layer observed. It could be considered that the current design and modifications are reasonable. Since some problems associated with the surface defects and thrombosis still existed, further improvement in fabrication process and quality control procedures with SEM are under way.

Ultrastructural Analysis of the Ontogenetic Development of Shoot Induced from Embryonic Axes of Costa Rican Bean Varieties (<i>Phaseolus vulgaris</i>L.) under <i>in Vitro</i>Conditions by Scanning Electronic Microscopy

Common bean (Phaseolus vulgaris L.) is an economic important crop and one of the major grain legumes for human consumption in Latin America, Africa and Asia. A morphological study of shoot induced from embryonic axes development in four Costa Rican bean varieties (Brunca, Huetar, Guaymi and Bribri) cultivated on MS media with or without 5 mg·L–1 de N6-benzylaminopurine (BAP) by scanning electron microscopy (SEM) was developed in the present work. Micrographs showed similarities and differences in the ultrastructure of the apical dome, epidermal surface, stomata and different types of trichomes in the varieties cultivated on organogenesis media. Genotypes with advantageous morphological characteristics for genetic transformation, in particular an exposed apical dome, were identified. This work will contribute to the optimization of the in vitro regeneration of four common bean varieties.

Adverse Effects of Permanent Waving and Hair Relaxation—Assessment by Scanning Electron Microscopy (SEM)

Permanent waving is very popular in Japan. Polypeptide chains (main chains) form the principal components of hair, and they are lined up longitudinally. Hair relaxation is also called straight permanent waving, and there are methods that change curly or wavy hair into straight hair. Hair damage as a result of winding, combing, and using high-temperature hairdressing irons is also often seen. By using scanning electron micrographs (SEM) we showed broken hairs and hair damage caused by permanent wave solutions. The hair damage is obvious when comparisons are made with the condition of the hair surface, condition of the cuticle, etc. Hair swelling by permanent wave solutions, manipulations such as winding, etc., inadequate rinsing with water, procedures on injured hair at the outset, etc., are considered possible reasons for any of these types of injury.

TiO₂Nanoparticles Induced Genotoxicity in Cultured Cells Using Atmospheric Scanning Electron Microscopy (ASEM)

Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to easily determine the cell incorporation of TiO2 NPs or related DNA damage, and to date, few studies have examined the different degrees of incorporation into cells according to the size of the TiO2 NPs particles and the presence or absence of cell specificity regarding DNA damage. This present study was therefore designed to examine COS7 cells that had incorporated TiO2 NPs using atmospheric scanning electron microscopy (ASEM). The results indicated that absorption of TiO2 NPs into cells and nuclear abnormalities had occurred. ASEM is a rapid and simple technique that enables the observation of samples immediately after fixation with glutaraldehyde and staining with phosphotungstic acid, and this method was suggested to be useful in screening for DNA damage.

Mineral Particles Found on the Hairs of Holy Maria-Magdalena Studied by Scanning Electron Microscopy and Elemental Analysis

The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these techniques of the hair surfaces allows us to observe and study some marble fragments that can originate from the walls of the sarcophagus in which Maria-Magdalena’s remains were kept. These new findings support the authenticity of the hair as traditionally reported in the French “tradition des Saints de Provence”.

Functional Microvascular Anatomy of the Horse Eye: A Scanning Electron Microscopic Study of Corrosion Casts

Objective: This study presents the microvasculature of the horse iris, ciliary process, retina, and choroid and discusses the functional significance of the vasculature. Procedure: Seven horses were used for this study. The ocular vascular system was injected with methylmethacrylate resin via the carotid artery, and the vascular corrosion casts were observed using a scanning electron microscope. Results: The iridial vessels showed a wavy course. The ciliary process was supplied by 2 arterial routes: the iridial and ciliary arterial circles. The subjects displayed a paurangiotic retina with retinal vessels extending only a short distance around the disc. The retinal arterioles and venules ran in closely related pairs, and the capillaries formed hairpin loops. No central retinal artery was seen in the equine eyes examined. The choriocapillaris in the avascular retina was arranged in honeycomb hexagon lobules and formed a more densely packed network than that in the vascular retina. There were 2 distinct venous drainage systems in the horse choroid: the vortex veins and the posterior ciliary veins. The vortex vein ampulla was flattened and showed a slit-like lumen at the merge site with the ophthalmic vein. The vortex veins demonstrated a marked constriction before leaving the eye. Discussion: The 2 choroidal drainage systems may compensate each other in event of occlusion. The ampulla and the constriction in the vortex veins may act as a valve regulating the blood flow to keep the eye at an optimum size and the intraocular pressure within the normal physiological range.

Study of a Novel Small Caliber Vascular Graft in a Canine Model with Optical and Scanning Electron Microscopy

A novel biological small-diameter vascular graft was evaluated in a canine model. 3 cm long segments with 4 mm I.D. were implanted end-to-end in the carotid position of 12 dogs for 6 months. Color Doppler sonography was performed at the first week post-operation, and angiography was then administered to 9 grafts at 4th week, 12th week and 24th week respectively to monitor the graft pantency and blood flow characteristics. Vascular samples containing the grafts were collected at 1st week, 8th week, 12th week and 24th week after implantation. Morphological changes of the grafts were observed by optical and scanning electron microscopic (SEM) studies and compared with that of the original prosthesis and the normal host vessel. All grafts were patent throughout the experiment except one graft. Histopathology and SEM demonstrated both a nearly complete inner capsule of varied thickness lining the graft luminal surface and connective tissue adventitia formation at one-week post-operation. The neointima became confluent at 8 weeks and then compact but had no signs of hyperplasia up to 12 weeks; meanwhile on the neointimal surface newly grown endothelial-like cells were migrating from the stoma to the middle portion. The grafts also illustrated endothelialization in many “islands” in the mid-segment luminal surface of the grafts. In addition, the closer distance the cells towards the stoma were, the more morphological similarity the cells with the normal endothelial were. Taken together, the biological vascular graft remained patent for 24 weeks as a carotid prosthesis, characterized by the early and complete neointima formation plus endothelialization starting before 12 weeks post grafting. Therefore, the graft seems suitable for reconstruction of vascular lesions in dogs. Further studies may be carried out to extend the graft application for the clinical use.

Study of the bones tissue reparation using nanostructured titanium implants with hydroxylapatite coatings by scanning electron microscopy

A method of medical implants (biocomposites) preparation based on nanostructured titanium with nanocrystalline bioactive hydroxylapatite coatings is developed. The operative treatment using these implants improves the regeneration of bone tissue for rats, as compared to the “false-operated” animals. The morphological data at 7, 14, 21, 45 days are obtained by means of scanning electron microscopy and discussed.

Visualization of atomic scale reaction dynamics of supported nanocatalysts during oxidation and ammonia synthesis using in-situ environmental(scanning) transmission electron microscopy

Reaction dynamics in gases at operating temperatures at the atomic level are the basis of heterogeneous gas-solid catalyst reactions and are crucial to the catalyst function.Supported noble metal nanocatalysts such as platinum are of interest in fuel cells and as diesel oxidation catalysts for pollution control,and practical ruthenium nanocatalysts are explored for ammonia synthesis.Graphite and graphitic carbons are of interest as supports for the nanocatalysts.Despite considerable literature on the catalytic processes on graphite and graphitic supports,reaction dynamics of the nanocatalysts on the supports in different reactive gas environments and operating temperatures at the single atom level are not well understood.Here we present real time in-situ observations and analyses of reaction dynamics of Pt in oxidation,and practical Ru nanocatalysts in ammonia synthesis,on graphite and related supports under controlled reaction environments using a novel in-situ environmental(scanning) transmission electron microscope with single atom resolution.By recording snapshots of the reaction dynamics,the behaviour of the catalysts is imaged.The images reveal single metal atoms,clusters of a few atoms on the graphitic supports and the support function.These all play key roles in the mobility,sintering and growth of the catalysts.The experimental findings provide new structural insights into atomic scale reaction dynamics,morphology and stability of the nanocatalysts.

50 years of scanning electron microscopy of bone——a comprehensive overview of the important discoveries made and insights gained into bone material properties in health,disease,and taphonomy

Bone is an architecturally complex system that constantly undergoes structural and functional optimisation through renewal and repair.The scanning electron microscope (SEM) is among the most frequently used instruments for examining bone.It offers the key advantage of very high spatial resolution coupled with a large depth of field and wide field of view.Interactions between incident electrons and atoms on the sample surface generate backscattered electrons,secondary electrons,and various other signals including X-rays that relay compositional and topographical information.Through selective removal or preservation of specific tissue components (organic,inorganic,cellular,vascular),their individual contribution(s) to the overall functional competence can be elucidated.With few restrictions on sample geometry and a variety of applicable sample-processing routes,a given sample may be conveniently adapted for multiple analytical methods.While a conventional SEM operates at high vacuum conditions that demand clean,dry,and electrically conductive samples,non-conductive materials (e.g.,bone) can be imaged without significant modification from the natural state using an environmental scanning electron microscope.This review highlights important insights gained into bone microstructure and pathophysiology,bone response to implanted biomaterials,elemental analysis,SEM in paleoarchaeology,3D imaging using focused ion beam techniques,correlative microscopy and in situ experiments.The capacity to image seamlessly across multiple length scales within the meso-micro-nano-continuum,the SEM lends itself to many unique and diverse applications,which attest to the versatility and user-friendly nature of this instrument for studying bone.Significant technological developments are anticipated for analysing bone using the SEM.

Scanning Electron Microscopy(SEM) Observations of Antennal Sensilla of Chrysopa pallens Rambur(Neuroptera：Chrysopidae)

[Objectives]The paper was to provide background information for ongoing research on relationship between smell and behavior of the green lacewing Chrysopa pallens（ Rambur）（ Neuroptera： Chrysopidae）. [Methods]The submicroscopic structure of antennal sensilla of C. pallens was examined using scanning electron microscopy. [Results]Antennae of female and male C. pallens were linear in shape and（ 1. 52 ± 0. 08） and（ 1. 58 ± 0. 23） cm in length,respectively. The scape and pedicel were composed of single sub-segment,while the flagellum consisted of 116 sub-segments,on which most sensilla distributed. The flagella of female and male antennae were（ 1. 44 ± 0. 04） and（ 1. 47 ± 0. 13） cm in length,respectively. Nine morphological sensilla types were recorded in both sexes,including four types of highly abundant and widely distributed sensilla trichodea（ ST Ⅰ,ST Ⅱ,ST Ⅲ and ST Ⅳ）,three types of sensilla basiconica（ SB Ⅰ,SB Ⅱ,and SB Ⅲ）,and one of each type of sensilla chaetica and B9 hm bristles. Although the shape,structure,numbers,and distribution of antennae of females and males were basically similar,major differences were recorded between the sexes in the length of some sensilla types. Both the ST Ⅲ and SB Ⅰ in female adults were significantly longer than that in male ones. Notably,SB Ⅱ was found only in female. [Conclusions]The paper laid a foundation for revealing the relationship between smell and behavior,playing a crucial role in promoting the important biological control effect of C. pallens in farmland ecological system.

Scanning Electron Microscopy of Antennae of Aphidoletes aphidimyza (Diptera: Cecidomyiidae)

The morphology of antennae of Aphidoletes aphidimyza was observed with a scanning electron microscope. The results showed that both male and female were fourteen segmented, the male was approximately 2000 μm and the female was 1050μm. Six types of sensillae on the antenna were observed, viz. chaetica （Ch）, trichoidea （Tr）, basiconica （Ba）, cavity （Ca）, styloid （St） and circumfila （Ci） on the antennae of A. aphidimyza. Sensillae Ch had a long external-process, with a base surrounded by membranous sockets and a length of about 67.5 μm. Sensillae Tr were distally curved and inserted into a depression, 61.0μm long. Sensillae Ba were peg-like and 4.7μm long on the antennae. Sensillae Ca were pit-like in appearance and the diameter of the pit was 1.2μm. Sensilla St was found on the second sub-segment flagellum of the male antennae. The length of the sensilla was about 21 μm and the diameter was 1.5μm. The circurnfila, which are a unique type of sensilla found only on cecidomyiid antennae, formed loops around each of the antennal sub-segments, and were attached to the surface by a series of stalks. Sensilla St was only present on male antenna. The number of Ba and Tr was almost the same in both sexes. There were more Sensilla Ca on the male antenna than on the female, while there was more Ch on the female.

Nanoparticles Production and Inclusion in <i>S. aureus</i>Incubated with Polyurethane: An Electron Microscopy Analysis

This study shows that submicron/nanoparticles found in bacterial cells (S. aureus) incubated with polyurethane (a material commonly used for prostheses in odontostomatology) are a consequence of biodestruction. The presence of polyurethane nanoparticles into bacterial vesicles suggests that the internalization process occurs through endocytosis. TEM and FIB/SEM are a suitable set of correlated instruments and techniques for this multi facet investigation: polyurethane particles influence the properties of S. aureus from the morpho-functional standpoint that may have undesirable effects on the human body. S. aureus and C. albicans are symbiotic microorganisms;it was observed that C. albicans has a similar interaction with polyurethane and an increment of the biodestruction capacity is expected by its mutual work with S. aureus.

IDENTIFICATION OF MARINE AEROSOL COMPONENT BY COMBINED NAA AND SCANNING ELECTRON MICROSCOPY WITH X—RAY ANALYSIS

The concentrations of 30 elements in aerosol particles collected in western Pacific ocean have been determined by INAA. The crustal element concentrations decrease with increasing distance from land over the remote area close to Asia land and fluctuate around its average value over the remote ocean area. The volatile elements exhibite average atmospheric concentrations that are higher than those expected from the flux of seasalt or the continental dust. In order to identify marine aerosol component originating from the continent or ocean, the aerosol particles are examined by scanning electron microscopy combined with energy dispersive X-ray spectroscopy. Particle phase structure shows that the crustal aerosol particles are not present internal mixtures with seasalt aerosol, and it also proves the long-range transport of crustal elements from continent to ocean.

Detecting Magma Mixing Processes Using Scanning Electron Microscopy Method

This review work explains some of the most important techniques to detect the occurrence of magma mixing phenomena in the volcanic rocks by using SEM （scanning electron microscope）. In particular, the most useful methods related to the different types of mixing are reviewed： complete mixing （blending） or incomplete mixing （mingling）. For blending, backscattered electron images and EDS （energy dispersive spectroscopy） are the most accurate methods： an example taken from a sample of ash of the 2007 Stromboli volcano eruption was used. For mingling, the best method is given by X-ray elemental mapping （in particular of Ca and Si）, as explained through the example taken from a sample of the 2003 explosive eruption of Soufriere Hills volcano. The aim of this work was to establish whereas would be useful to use backscattered eletron images, EDS, or X-ray elemental mapping techniques, according to the different types of mixing that occur very often in magmatic systems.

Comparison of scanning electron microscopy findings regarding biofilm colonization with microbiological results in nasolacrimal stents for external, endoscopic and transcanalicular dacryocystorhinostomy

AIM:To compare bacterial biofilm colonization in lacrimal stents following external dacryocystorhinostomy(EX-DCR),endoscopic dacryocystorhinostomy(EN-DCR),and transcanalicular dacryocystorhinostomy(TC-DCR)with multidiode laser.METHODS:This prospective study included 30consecutive patients with nasolacrimal duct obstruction who underwent EXT-,EN-,or TC-DCR.Thirty removed lacrimal stent fragments and conjunctival samples were cultured.The lacrimal stent biofilms were examined by scanning electron microscopy(SEM).RESULTS:Eleven(36.7%)of the 30 lacrimal stent cultures were positive for aerobic bacteria(most commonly Staphylococcus epidermidis and Pseudomonas aeruginosa).However anaerobic bacteria and fungi were not identified in the lacrimal stent cultures.Twenty-seven(90%)patients had biofilmpositive lacrimal stents.The conjunctival culture positivity after the DCR,biofilm positivity on stents,the grade of biofilm colonization,and the presence of mucus and coccoid and rod-shaped organisms did not significantly differ between any of the groups(P】0.05).However,a significant difference was found when the SEM results were compared to the results of the lacrimal stent and conjunctival cultures(P【0.001).CONCLUSION:Type of dacryocystorhinostomy(DCR)surgery did not affect the biofilm colonization of the lacrimal stents.SEM also appears to be more precise than microbiological culture for evaluating the presence of biofilms on lacrimal stents.

Three-Dimensional Analysis of Melanosomes Isolated from B16 Melanoma Cells by Using Ultra High Voltage Electron Microscopy

Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some interesting structural features were found inside and outside of the melanosomes. By SEM observation, the melanosomes were ellipsoid shape, their surface was not smooth and was covered with rough substructure, 10 to 20 nm particles. By TEM, uneven structure and micro particles were observed in the melanosomes. Furthermore, three-dimensional analysis was tried by using the ultra-high voltage electron microscopy(UHVEM). Micrographs of the melanosomes were taken at various tilted angles by UHVEM, after preparing 500 nm thickness specimens stained with lead citrate. From the micrographs collected, the three-dimensional structures were reconstructed by using i-mode software. Melanin stained by lead and non stained parts was clearly observed in the reconstructed structure. Non stained parts were round, regular size, and distributed widely in the melanosomes.

Scanning Electron Microscopy (SEM) of the Bug Eye and Sand Coral

We present a Scanning Electron Microscopy (SEM) technique for the characterisation of biological and non-biological samples at nano-scale level. Scanning Electron Microscopy has been around for a long while especially in material science laboratories in developed countries. The SEM has enabled scientist to have a better understanding of microstructure by providing unsurpassed optical magnifications of samples. In this introductory paper, we introduce the techniques of using SEM to capture highly magnified microstructure of a fly found on an African soybean (Glycine max) seed. We are able to estimate the number of lenses in each eye and zoom into features that could describe its life characteristics. Hexagonal lenses are estimated to have sizes ranging from 14 um to 19 um. This paper also presents a finding of a sea coral “pie like structure” on a single grain of sand used for water filtration.