The influence of age on valve disease in patients with varicose veins analysed by transmission electron microscopy and stereology

VASA ◽  
2018 ◽  
Vol 47 (5) ◽  
pp. 409-416 ◽  
Author(s):  
Wolfgang G. Mouton ◽  
Michael O. Wagner ◽  
Beat Haenni ◽  
Kim T. Mouton ◽  
Matthias Ochs ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Varicose Veins ◽  
Rank Correlation ◽  
Venous Valve ◽  
Ultrastructural Morphology ◽  
Spearman’S Rank Correlation ◽  
Transmission Electron ◽  
The Mean ◽  
Venous Disorders

Abstract. Background: The aim of this study was to investigate the influence of age on the ultrastructure of venous valve morphology in patients with C2 classified chronic venous disorders according to the CEAP classification. Patients and methods: The study population consisted of 16 consecutive patients with varicose veins (C2). The mean age was 49.8 years (30–66). The (pre-) terminal valve including the vessel wall was harvested within the proximal 2 centimetres of the great saphenous vein. The mean thickness (volume-to-surface ratio = V/S ratio) of elastin, collagen, endothelium and of the entire valve was determined. A blinded morphologist performed the examination by transmission electron microscopy and stereology. Analyses by Pearson’s product moment correlation, Kendall’s tau and Spearman’s rank correlation were performed to investigate whether there is a correlation between age and the ultrastructural morphology. Results: Stereological analysis of the valves demonstrated a mean V/S ratio (signifying a thickness estimation) for elastin of 0.87 μm3/μm2, for collagen of 18.0 μm3/μm2, for endothelium of 0.65 μm3/μm2, and for the entire valve of 25.2 μm³/μm². Statistical analyses showed no statistically significant correlation between age and the ultrastructural morphology in this patient group. Conclusions: The ultrastructural morphology of the venous valves in chronic venous disorders may not depend on age in patients presenting with C2 disease. This conclusion may or may not apply to all C classes as we investigated a homogenous group of patients with C2 limbs.

Size of pores of Kohn: influence of transpulmonary and vascular pressures

1981 ◽  
Vol 51 (3) ◽  
pp. 739-745 ◽  
Author(s):  
R. W. Mazzone ◽  
S. Kornblau
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Pore Size ◽  
Minimum Diameter ◽  
Transmission Electron ◽  
Zone Ii ◽  
The Mean ◽  
Alveolar Septa ◽  
Collateral Ventilation

We investigated the influence of transpulmonary (Ptp) and vascular pressures on the size of the pores of Kohn in primary alveolar septa. Dogs lungs, perfused and ventilated in situ, were rapidly frozen with Freon 22 in zone II or III conditions following deflation to Ptp of 5, 15, or 25 cmH2O. Frozen samples were freeze-substituted for transmission electron microscopy. Five fields containing at least one pore each were selected randomly from each section of tissue, and the minimum diameter visible in the cut section was measured. For both zone II and III conditions, as Ptp increased, mean pore size increased. The mean pore size under zone III conditions was 1.2015, 1.788, and 2.249 micrometer for Ptp of 5, 15, and 25 cmH2O, respectively. For zone 2 conditions, the corresponding values were 1.1438, 1,8757, and 2.08 micrometer. For both zones II and III, increasing capillary hydrostatic pressure had no significant effect on pore size. The results support the notion that alveolar pores can increase collateral ventilation by dynamically stretching as Ptp increases. Capillary pressure does not influence pore size probably because of collagen fibers, which surround the pore lumen. Presumably, these fibers resist encroachment of capillaries on the pore lumen as vascular pressures increase.

Ultrastructural morphology of the uredium and collar formation during urediosporogenesis of Uromyces transversalis on gladiolus

1990 ◽  
Vol 68 (3) ◽  
pp. 605-612 ◽  
Author(s):  
Johan F. Ferreira ◽  
F. H. J. Rijkenberg
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Basal Cell ◽  
Basal Layer ◽  
Ultrastructural Morphology ◽  
Transmission Electron

The transverse uredia of Uromyces transversalis on gladiolus leaves were investigated by scanning and transmission electron microscopy. The basal cell forms one or more protuberances distally, each being delimited by a septum to become a urediospore initial. The initial elongates and lays down a septum to form a urediospore and pedicel. The first protuberance on the basal cell forms holoblastically, and evidence is found at the same locus for the subsequent enteroblastic formation of up to three successive urediospore initials. The pedicel wall of a spore thus formed remains on the basal cell and becomes a collar around the next protuberance. The basal layer of the two-layered septum that delimited the pedicel from the basal cell grows out to form the wall of the subsequent protuberance, and in the process ruptures and laterally displaces the terminal septal layer. A new basipetal septum forms to delimit the subsequent urediospore initial. In this manner, several collars form retrogressively and concentrically at one locus.

Polyethyleneimine Modified Biocompatible Poly(N-isopropylacrylamide)-Based Nanogels for Drug Delivery

2008 ◽  
Vol 8 (5) ◽  
pp. 2377-2384 ◽  
Author(s):  
Chang-Yun Quan ◽  
Hua Wei ◽  
Yun-Xia Sun ◽  
Si-Xue Cheng ◽  
Kun Shen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Drug Delivery ◽  
Transmission Electron Microscopy ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Transmission Electron ◽  
Potential Applications ◽  
Different Temperatures ◽  
The Mean ◽  
Stimuli Sensitive

A series of biocompatible and stimuli-sensitive poly(N-isopropylacrylamide-co-propyl acrylic acid) (P(NIPAAm-co-PAAc)) nanogels were synthesized by emulsion polymerization. In addition, polyethyleneimine (PEI) was further grafted to modify the PNIPAAm-based nanogels. The P(NIPAAm-co-PAAc)-g-PEI nanogels exhibited good thermosensitivity as well as pH sensitivity. Transmission electron microscopy (TEM) showed that the P(NIPAAm-co-PAAc)-g-PEI and P(NIPAAm-co-PAAc) nanogels displayed well dispersed spherical morphology. The mean sizes of the nanogels measured by dynamic light scattering (DLS) were from 100 nm to 500 nm at different temperatures. The cytotoxicity study indicated P(NIPAAm-co-PAAc) nanogels exhibited a better biocompatibility than both PNIPAAm nanogel and P(NIPAAm-co-PAAc)-g-PEI nanogel although all the three kinds of nanogels did not exhibit apparent cytotoxicity. The drug-loaded nanogels, especially the PEI-grafted nanogels, showed temperature-trigged controlled release behaviors, indicating the potential applications as an intelligent drug delivery system.

scholarly journals Transmission Electron Microscopy as a Powerful Tool to Investigate the Interaction of Nanoparticles with Subcellular Structures

2021 ◽  
Vol 22 (23) ◽  
pp. 12789
Author(s):  
Manuela Malatesta
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Nanoparticle Uptake ◽  
Ultrastructural Morphology ◽  
Functional Value ◽  
Transmission Electron ◽  
Biological Environment ◽  
Microscopy Techniques ◽  
The Impact

Nanomedical research necessarily involves the study of the interactions between nanoparticulates and the biological environment. Transmission electron microscopy has proven to be a powerful tool in providing information about nanoparticle uptake, biodistribution and relationships with cell and tissue components, thanks to its high resolution. This article aims to overview the transmission electron microscopy techniques used to explore the impact of nanoconstructs on biological systems, highlighting the functional value of ultrastructural morphology, histochemistry and microanalysis as well as their fundamental contribution to the advancement of nanomedicine.

scholarly journals Comparative Study of Chitosan and Oligochitosan Coatings on Mucoadhesion of Curcumin Nanosuspensions

Pharmaceutics ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2154
Author(s):  
Gye Hwa Shin ◽  
Jun Tae Kim
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Morphological Changes ◽  
Transmission Electron ◽  
Efficient Delivery ◽  
Ft Ir ◽  
The Mean ◽  
Insoluble Compounds ◽  
Ft Ir Spectroscopy

Curcumin nanosuspensions (Cur-NSs), chitosan-coated Cur-NSs (CS-Cur-NSs), and oligochitosan-coated Cur-NSs (OCS-Cur-NSs) were prepared by using an ultrasonic homogenization technique. The mean particle size of Cur-NSs was 210.9 nm and significantly (p < 0.05) increased to 368.8 nm by CS coating and decreased to 172.8 nm by OCS coating. Encapsulation efficiencies of Cur-NSs, CS-Cur-NSs, and OCS-Cur-NSs were 80.6%, 91.4%, and 88.5%, respectively. The mucin adsorption of Cur-NSs was steeply increased about 3–4 times by CS and OCS coating. Morphological changes of these NSs were studied using circular dichroism spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM). Thus, CS-Cur-NSs and OCS-Cur-NSs showed great potential as mucoadhesive nano-carriers for the efficient delivery of water insoluble compounds like curcumin to the gastrointestinal system.

scholarly journals Semen quality and sperm ultrastructure of Himalayan snowtrout Schizothorax plagiostomus Heckel, 1838

2017 ◽  
Vol 64 (1) ◽  
pp. 49
Author(s):  
Gaurav Bhatt ◽  
Shurveer Singh ◽  
Vivek Bahugua ◽  
Ashish K. Chowdhary ◽  
Siddhand Bhardwaj ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Semen Quality ◽  
Total Lipids ◽  
Sperm Ultrastructure ◽  
Sperm Density ◽  
Transmission Electron ◽  
The Mean ◽  
Breeding Seasons ◽  
Schizothorax Plagiostomus

The aim of this study was to characterise physical and biochemical aspects of semen as well as to investigate the fine structure of spermatozoa of the Himalayan snowtrout Schizothorax plagiostomus Heckel, 1838 using scanning and transmission electron microscopy. The species breed twice in a year and semen was collected during both seasons, i.e. from 24 males in February and March, 2015 and from 30 males in September and October, 2015. Size of the fish ranged from 13.5 to 36 cm in February-March and 12.3 to 38 cm in September-October. The mean milt volume (ml), sperm density (×1010 ml-1) and spermatocrit (%) values were 2.25±1.26, 2.22±0.53 and 78.87± 8.25 in February-March and 2.12±1.25, 2.12±0.52 and 75.54±8.23 in September-October respectively. Biochemical parameters of seminal plasma viz., total protein (g dl-1), carbohydrates (mg dl-1) and total lipids were 0.312±0.05, 1.348±0.07 and 26.4±2.23 in February-March and 0.340±0.05, 1.34±0.1 and 26.4±3.19 in September-October respectively. Scanning and transmission electron microscopy studies of sperm revealed that the sperm was composed of an ovoid shaped head without acrosome, ellipsoidal midpiece with mitochondria and tail or flagellum. Flagellum had a typical 9+2 axoneme arrangement. The mean length (μm) of head, midpiece, flagella and total length of sperm were 1.82±0.24, 0.35±0.07, 20.18±0.79 and 22.3±3 respectively. For both the breeding seasons, sperm motility decreased significantly with time post-activation.

Light and Electron Microscopic Observation of Regenerated Fungiform Taste Buds in Patients with Recovered Taste Function after Severing Chorda Tympani Nerve

2011 ◽  
Vol 120 (11) ◽  
pp. 713-721 ◽  
Author(s):  
Takehisa Saito ◽  
Tetsufumi Ito ◽  
Norihiko Narita ◽  
Takechiyo Yamada ◽  
Yasuhiro Manabe
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Taste Buds ◽  
Chorda Tympani ◽  
Chorda Tympani Nerve ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
The Mean

Objectives: The aim of this study was to evaluate the mean number of regenerated fungiform taste buds per papilla and perform light and electron microscopic observation of taste buds in patients with recovered taste function after severing the chorda tympani nerve during middle ear surgery. Methods: We performed a biopsy on the fungiform papillae (FP) in the midlateral region of the dorsal surface of the tongue from 5 control volunteers (33 total FP) and from 7 and 5 patients with and without taste recovery (34 and 29 FP, respectively) 3 years 6 months to 18 years after surgery. The specimens were observed by light and transmission electron microscopy. The taste function was evaluated by electrogustometry. Results: The mean number of taste buds in the FP of patients with completely recovered taste function was significantly smaller (1.9 ± 1.4 per papilla; p < 0.01) than that of the control subjects (3.8 ± 2.2 per papilla). By transmission electron microscopy, 4 distinct types of cell (type I, II, III, and basal cells) were identified in the regenerated taste buds. Nerve fibers and nerve terminals were also found in the taste buds. Conclusions: It was clarified that taste buds containing taste cells and nerve endings do regenerate in the FP of patients with recovered taste function.

The Comparative Ultrastructure of Fibrin Induced by Thrombin and by Staphylocoagulase

1975 ◽  
Vol 34 (01) ◽  
pp. 223-235 ◽  
Author(s):  
M. J. S King ◽  
M. S Morris ◽  
M Tager
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
T Test ◽  
Test Analysis ◽  
A Value ◽  
Transmission Electron ◽  
The Mean ◽  
Comparative Ultrastructure

SummaryFibrin induced by the action of thrombin and by staphylocoagulase was studied by transmission electron microscopy.Periodic striations were consistently observed in the negatively stained preparations of both fibrins. When 4200 major periods in the thrombin fibrin system were measured the mean length was 228 Å. For 3666 major periods in the coagulase fibrin system the mean length was 223 Å. While the T test analysis of these values gave a value of 10, it is noteworthy that the differences are well within the scatter of periodicity reported in the literature for thrombin-induced fibrin.Gross inspection of the preparations indicated that the coagulase-induced fibrin had a knottier appearance and was accompanied by a greater amount of background debris than the thrombin-induced fibrin.

The Determination of Evolving Microstructure Using Constitutive Relationships

1999 ◽  
Vol 578 ◽  
Author(s):  
B.J. Diak ◽  
S. Saimoto
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Size ◽  
Tensile Deformation ◽  
Constitutive Parameter ◽  
Upper Limit ◽  
Transmission Electron ◽  
The Mean ◽  
Slip Distance

AbstractThe evolution of the constitutive parameter, the mean slip distance, λ, is monitored during tensile deformation of 3.2 μm grain size aluminum at 200 K. Transmission electron microscopy (TEM) confirms that the grain size, D, sets an upper limit to λ.

Melting process of nanometer-sized In particles embedded in an Al matrix synthesized by ball milling

1996 ◽  
Vol 11 (11) ◽  
pp. 2841-2851 ◽  
Author(s):  
H. W. Sheng ◽  
J. Xu ◽  
L. G. Yu ◽  
X. K. Sun ◽  
Z. Q. Hu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Size ◽  
Melting Point ◽  
Melting Point Depression ◽  
X Ray ◽  
Transmission Electron ◽  
Mean Grain Size ◽  
The Mean ◽  
Al Matrix

Dispersions of nanometer-sized In particles embedded in an Al matrix (10 wt. % In) have been synthesized by ball milling of a mixture of Al and In powders. The as-milled product was characterized by using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray spectrometer (EDX), transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HREM), respectively. It was found that In and Al are pure components immiscible with each other, with nanometer-sized In particles dispersively embedded in the Al matrix. The melting behavior of In particles was investigated by means of differential scanning calorimeter (DSC). The calorimetric measurements indicate that both the melting point and the melting enthalpy of the In nanoparticles decrease with increasing milling time, or refinement of the In particles. Compared to its bulk melting temperature, a melting point depression of 13.4 K was observed when the mean grain size of In is 15 nm, and the melting point depression of In nanoparticles is proportional to the reciprocal of the mean grain size. The melting enthalpy depression was interpreted according to the two-state concept for the nanoparticles. Melting of the interface was deduced to be an exothermal process due to its large excess energy/volume.

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