scholarly journals Differentiating Trypanosoma cruzi in a Host Mammalian Cell Imaged in Aqueous Liquid by Atmospheric Scanning Electron Microscopy

2022 ◽  
Author(s):  
Yuko Takagi ◽  
Mari Sato ◽  
Masami Naya ◽  
Chikara Sato
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Trypanosoma Cruzi ◽  
Mammalian Cell ◽  
Cell Plasma Membrane ◽  
Content Type ◽  
Cell Plasma ◽  
Internal Structures ◽  
Infectious Stage ◽  
Scanning Electron

Using Atmospheric Scanning Electron Microscopy (ASEM), we visualized interaction between infectious stage of Trypanosoma cruzi and completely intact host mammalian cell. Plasma membrane appears translucent under ASEM, which not only enables direct observation of T. cruzi within its host cell, but also reveals internal structures of the parasite itself.

scholarly journals Indirect Immunodetection of Fungal Fragments by Field Emission Scanning Electron Microscopy

2015 ◽  
Vol 81 (17) ◽  
pp. 5794-5803 ◽  
Author(s):  
Komlavi Anani Afanou ◽  
Anne Straumfors ◽  
Asbjørn Skogstad ◽  
Ajay P. Nayak ◽  
Ida Skaar ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Emission ◽  
Polyclonal Antibodies ◽  
Detection Methods ◽  
Indoor Environments ◽  
Content Type ◽  
Freeze Dried ◽  
Scanning Electron

ABSTRACTSubmicronic fungal fragments have been observed inin vitroaerosolization experiments. The occurrence of these particles has therefore been suggested to contribute to respiratory health problems observed in mold-contaminated indoor environments. However, the role of submicronic fragments in exacerbating adverse health effects has remained unclear due to limitations associated with detection methods. In the present study, we report the development of an indirect immunodetection assay that utilizes chicken polyclonal antibodies developed against spores fromAspergillus versicolorand high-resolution field emission scanning electron microscopy (FESEM). Immunolabeling was performed withA. versicolorfragments immobilized and fixed onto poly-l-lysine-coated polycarbonate filters. Ninety percent of submicronic fragments and 1- to 2-μm fragments, compared to 100% of >2-μm fragments generated from pure freeze-dried mycelial fragments ofA. versicolor, were positively labeled. In proof-of-concept experiments, air samples collected from moldy indoor environments were evaluated using the immunolabeling technique. Our results indicated that 13% of the total collected particles were derived from fungi. This fraction comprises 79% of the fragments that were detected by immunolabeling and 21% of the spore particles that were morphologically identified. The methods reported in this study enable the enumeration of fungal particles, including submicronic fragments, in a complex heterogeneous environmental sample.

Ovine pericardium as a new material for duraplasty

1996 ◽  
Vol 84 (3) ◽  
pp. 508-513 ◽  
Author(s):  
Jan Pařízek ◽  
Zdeněk Husěk ◽  
Pavel Měřička ◽  
Josef Téra ◽  
Stanislav Němeček ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Host Tissue ◽  
Γ Irradiation ◽  
Content Type ◽  
Dural Substitute ◽  
Freeze Dried ◽  
New Material ◽  
Fine Print ◽  
Scanning Electron

✓ The authors report on their 2 1/2-year clinical experience using a dural substitute, ovine pericardium, stabilized with 0.3% glutaraldehyde, flat freeze-dried, and sterilized with γ-irradiation. Packaging of the ovine pericardium in double-plastic transparent bags allows simple storage in operating rooms and the opportunity for the surgeon to choose an ideal graft according to its shape, size, and plasticity. The ovine pericardia were examined histologically and by transmission and scanning electron microscopy in their native, freeze-dried, and irradiated forms. The final product is composed solely of pericardium fibrosum interwoven with artificially formed extracellular microcavities that serve as natural pores for the ingrowth of host tissue. The surfaces of the grafts appear smooth on the inner and rough on the outer sides. Sixteen grafts were examined macroscopically at autopsy and four of these were also examined histologically to illustrate their successful healing with no adhesion to the underlying brain. As a new dural substitute, ovine pericardium proved to be superior to bovine and allogeneic pericardia because of its workability, flexibility, and reduced thickness. In a study of 120 grafts, all but one healed without complications.

scholarly journals Increased Water Activity Reduces the Thermal Resistance of Salmonella enterica in Peanut Butter

2013 ◽  
Vol 79 (15) ◽  
pp. 4763-4767 ◽  
Author(s):  
Yingshu He ◽  
Ye Li ◽  
Joelle K. Salazar ◽  
Jingyun Yang ◽  
Mary Lou Tortorello ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Resistance ◽  
Water Activity ◽  
Salmonella Enterica ◽  
Morphological Changes ◽  
Peanut Butter ◽  
Content Type ◽  
The Difference ◽  
Scanning Electron

ABSTRACTIncreased water activity in peanut butter significantly (P< 0.05) reduced the heat resistance of desiccation-stressedSalmonella entericaserotypes treated at 90°C. The difference in thermal resistance was less notable when strains were treated at 126°C. Using scanning electron microscopy, we observed minor morphological changes ofS. entericacells resulting from desiccation and rehydration processes in peanut oil.

scholarly journals Morphological evidence by scanning electron microscopy of excretion of metacyclic forms of Trypanosoma cruzi in vector's urine

1988 ◽  
Vol 83 (3) ◽  
pp. 361-365 ◽  
Author(s):  
Rodrigo Zeledon ◽  
Rodolfo Bolaños ◽  
M. R. Espejo Navarro ◽  
Miguel Rojas
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Division ◽  
Trypanosoma Cruzi ◽  
Urine Flow ◽  
The Other ◽  
Rectal Gland ◽  
Morphological Evidence ◽  
Different Levels ◽  
Scanning Electron

Comparision by scanning electron microscopy (SEM) of Trypanosoma cruzi flagellates attached to the cuticle of the rectal gland of infected Dipetalogaster maxima nymphs, showed marked differences before amd after feeding. Before feeding numerous metacyclic trypomastigotes were observed among the abundant epimastigotes that formed the carpet of flagellates. On the other hand, in insects that were allowed to urinate for 24 hours after a meal, the metacyclics were scarce,indicating that they had been detached by the urine flow. An asymetric type of cell division, probably originating both an epi-and a trypomastigote, was occasionally observed. The occurrence of swellings at different levels of the flagella of epimastigotes suggests that secondary sites of attachment may be common.

Morphological studies of human arteriovenous malformations

1985 ◽  
Vol 63 (3) ◽  
pp. 421-425 ◽  
Author(s):  
Peter M. Klara ◽  
Eugene D. George ◽  
Dennis E. McDonnell ◽  
Paul H. Pevsner
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Arteriovenous Malformations ◽  
Lattice Structure ◽  
Balloon Catheter ◽  
Surgical Removal ◽  
Content Type ◽  
Morphological Studies ◽  
Micro Channels ◽  
Scanning Electron

✓ Ten patients with symptomatic arteriovenous malformations (AVM's) underwent embolization with isobutyl 2-cyanoacrylate (Bucrylate) delivered via a mini-balloon catheter according to the protocol of George and Pevsner. These patients underwent surgical removal of their embolized AVM, and surgical specimens were evaluated by light and scanning electron microscopy. Ten other patients with AVM's underwent surgical resection without prior embolization, and these surgical specimens were evaluated in a similar manner. Results from this study indicate that Bucrylate incites an inflammatory response characterized by foreign-body giant cells. This reaction was present as early as 3 weeks after embolization and persisted in specimens resected almost 1 year after the last embolization. No such reaction was observed in unembolized AVM's. Both light and scanning electron microscopy demonstrated a lattice structure of the Bucrylate embolus within the AVM vessels. These studies also demonstrated micro-channels within the Bucrylate embolus and the presence of what appears to be normal red blood cells within the latticework of the embolus. Vascular endothelium not in direct contact with the Bucrylate embolus retains a normal morphology as revealed by scanning electron microscopy.

Synthesis, characterisation and tribological evaluation of surface-capped molybdenum sulphide nanoparticles as efficient antiwear bio-based lubricant additives

2017 ◽  
Vol 69 (3) ◽  
pp. 378-386 ◽  
Author(s):  
Sharul Hafiq Roslan ◽  
Sharifah Bee Abd Hamid ◽  
Nurin Wahidah Mohd Zulkifli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Wear Scar ◽  
Gravimetric Analysis ◽  
Content Type ◽  
X Ray ◽  
Lubricant Oil ◽  
Wear Reduction ◽  
Molybdenum Sulphide ◽  
Scanning Electron

Purpose The purpose of this study is to synthesise and characterise surface-capped molybdenum sulphide (SCMS) nanoparticles using the solvothermal method and to investigate their tribological behaviour towards friction improver and wear reduction for bio-based lubricant oil additives. Design/methodology/approach The design of the experiment was to use freshly prepared molybdenum (II) acetate, thioacetamide, fatty acid and hexane as the solvent inside an autoclave vessel which is heated at high temperature and pressure. Various types of fatty acids were used as the capping agent, such as caproic, lauric, stearic and oleic acid. The SCMS nanoparticles formed were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffractometry, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and thermal gravimetric analysis. These nanoadditives were then blended into pentaerythrityl tetracaprylate/caprate ester at 0.05 Wt.% concentration. The formulated bio-based lubricant oil samples were tested for viscosity, viscosity index (VI) and density based on standard method ASTM D445 and ASTM D2270. A four-ball test was carried out for determination of coefficient of friction and wear scar diameter. The wear scar formed on the surface of the ball bearing was analysed using scanning electron microscopy. Findings The characterisation results showed that SCMS nanoparticles were successfully formed with amorphous ball-like structure, and the presence of the capping layer surrounding the nanoparticles was confirmed. Then, the formulated bio-based lubricant oil with addition of nanoadditives displays improved tribological properties in term of VI, antifriction and wear reduction. Originality/value This research provides a synthesis method of producing SCMS nanoparticles using the organomolybdenum complex as the chemical precursor through the solvothermal reaction approach. Besides that, it also gives an alternative antifriction and antiwear nanoadditive for formulation of the bio-based lubricant oil.

Physicochemical, textural, color, nutritional, scanning electron microscopy and sensorial characterization of calcium-rich breads fortified with sesame, malted finger millet, cumin and moringa leaves

2019 ◽  
Vol 50 (1) ◽  
pp. 47-60 ◽  
Author(s):  
Dipika Agrahar-Murugkar ◽  
Preeti Dixit-Bajpai
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Finger Millet ◽  
Milk Powder ◽  
Calcium Content ◽  
Content Type ◽  
Flour Dough ◽  
Skimmed Milk ◽  
Skimmed Milk Powder ◽  
Scanning Electron

Purpose The purpose of this study is to examine the effect of calcium-rich ingredients such as sesame, skimmed milk powder, moringa leaves, cumin seeds and finger millet on flour, dough and breads with the objective of developing bread with higher calcium content and to investigate whether it maintains quality traits that guarantee its acceptability by consumers by testing textural, scanning electron microscopy and nutritional and sensorial parameters. Design/methodology/approach Refined flour was fortified with skimmed milk powder (SMP), sesame, moringa leaves and cumin (T1), SMP, sesame and malted finger millet (T2) and SMP and sesame (T3). Refined flour dough and breads served as control (C). The physicochemical, textural, scanning electron microscopy, nutritional and sensory parameters of flour, dough and breads were evaluated. Findings Significantly (p < 0.01) higher stickiness values of dough were obtained by refined flour dough-C (50.3 N); refined flour dough fortified with SMP and sesame - T3 (42.2 N); Refined flour dough fortified with sesame, SMP and malted finger millet -T2 (38.4 N); and refined flour dough fortified with sesame, SMP, moringa leaves and cumin -T1 (33.5 N). Oven spring in breads was 1.4 in C and decreased significantly (p < 0.01) to T3-1.0, T1-0.9 and T2-0.8. Chewiness values of T3 (4.1) was similar to C bread, whereas T1 and T2 showed significantly (p < 0.01) lower values. Scanning electron microscopy images of bread microstructure showed fortification of bread resulted in intermittent but more prominent gluten structure in test breads than control. The highest calcium content was observed in T1 (268 mg/100 g), followed by T2 (231 mg/100 g) and T3 (211 mg/100 g). The incorporation of dried moringa leaves and cumin seeds enhanced the appearance, aroma, taste and flavor of T1. Research limitations/implications The study shows that texturally and sensorially acceptable nutritious breads can be produced through natural fortification. Nutrients from naturally fortified foods are better absorbed and assimilated by the body. Calcium-fortified breads, each with its own distinctive taste and texture, showed high values in the sensory evaluation test. Originality/value The incorporation of calcium and protein-rich ingredients such as SMP, moringa leaves, cumin, malted finger millet and sesame would yield calcium enriched breads superior to the commonly consumed plain refined wheat flour bread with respect to textural, nutritional, functional and sensory attributes and have high potential to alleviate calcium deficiency in vulnerable groups.

Scanning electron micrographic study of vascular lesions caused by microvascular needles and suture

1980 ◽  
Vol 53 (1) ◽  
pp. 32-36 ◽  
Author(s):  
David M. Pagnanelli ◽  
T. Glenn Pait ◽  
Hugo V. Rizzoli ◽  
Arthur I. Kobrine
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Blood Vessels ◽  
Vascular Trauma ◽  
Vascular Lesions ◽  
Content Type ◽  
Fine Print ◽  
Scanning Electron

✓ The authors studied the damage to blood vessels 1 to 2 mm in diameter caused by the most commonly used types of microvascular needle. Excluding variables introduced by anastomosis, the study focused specifically on lesions attributable only to the needle and suture. Scanning electron microscopy revealed four distinct types of lesion. A theory is proposed to explain the mechanisms whereby these lesions were produced, and a needle design is recommended that may aid in minimizing vascular trauma.

Scanning Electron Microscopy of Ethanol Infiltrated Freeze-Fractured Cell Pellets

1974 ◽  
Vol 32 ◽  
pp. 98-99
Author(s):  
William G. Henk ◽  
Ben O. Spurlock
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Critical Point ◽  
Freeze Drying ◽  
Cultured Cells ◽  
Resolving Power ◽  
Ice Crystal ◽  
Internal Structures ◽  
Critical Point Drying ◽  
Scanning Electron

The increased depth of focus and superior resolving power of the scanning electron microscope provide advantages over the light microscope in viewing the external morphology of cultured cells and protists. Internal structures have, however, proved more difficult to observe. Freeze drying adequately preserves surface structures but results in poorly preserved cytoplasmic elements due to ice crystal damage. Critical point drying results in good preservation of both surface and cytoplasmic fine structure. Attempts to cut or break critical point dried material, however, result in plastic deformation of the cells. Humphreys, et al, recently introduced freeze fracturing of ethanol infiltrated tissues for biological scanning electron microscopy. We have modified and applied their technique and obtained similar results with Paramecium sp. obtained from mass cultures.

Sign in / Sign up

Export Citation Format

Share Document