scholarly journals Influence of chemistry and fiber diameter of electrospun PLA, PCL and their blend membranes, intended as cell supports, on their biological behavior

2021 ◽  
pp. 107364
Author(s):  
María Herrero-Herrero ◽  
Sara Alberdi-Torres ◽  
Maria Luisa González-Fernández ◽  
Guillermo Vilariño-Feltrer ◽  
José Carlos Rodríguez-Hernández ◽  
...  
Keyword(s):  
Fiber Diameter ◽  
Biological Behavior ◽  
Blend Membranes

Physicochemical and biological investigation of oxygen plasma modified electrospun polyurethane scaffolds for connective tissue engineering application

2019 ◽  
Vol 39 (6) ◽  
pp. 526-533
Author(s):  
Farnaz Ghorbani ◽  
Ali Zamanian
Keyword(s):  
Tissue Engineering ◽  
Plasma Treatment ◽  
Oxygen Plasma ◽  
Fiber Diameter ◽  
Engineering Application ◽  
Biological Behavior ◽  
Plasma Modification ◽  
Diameter Distribution ◽  
Oxygen Plasma Treatment ◽  
Tissue Engineering Application

AbstractIn this study, electrospinning was selected to fabricate randomly oriented polyurethane (PU) nanofibers for tissue engineering application, and the surface of scaffolds was exposed to oxygen plasma flow. The morphology structure of the PU scaffolds before and after oxygen plasma treatment was observed using scanning electron microscopy (SEM) micrographs, and the fiber diameter distribution was measured using Image J software. The results demonstrated that oxygen plasma modification reduces the fiber diameter without any other special effects on fiber microstructure. Water drop contact angle and swelling ratio of PU constructs were performed to estimate the water-scaffolds interactions. The results revealed improvement of hydrophilicity by oxygen plasma treatment. Atomic force microscopy test was done to analyze a topological characteristic of the scaffolds, and it was found out that oxygen plasma treatment decreases the roughness of the scaffolds. The biological behavior of the scaffolds was investigated by SEM observation and MTT assay after L-929 fibroblast cells culture.In vitroassays demonstrated biocompatibility, cellular attachments, and filopodia formation on plasma modified samples. These results suggest that oxygen plasma treatment improves the physicochemical and biological properties of PU scaffolds to create a more hydrophilic surface which facilitates cell attachments and proliferation.

Quantitative Diameter Measurements of Chromatin and TMV Fibers in the Freeze-Dried State

1988 ◽  
Vol 46 ◽  
pp. 170-171
Author(s):  
B. D. Athey ◽  
A. L. Stout ◽  
M. F. Smith ◽  
J. P. Langmore
Keyword(s):  
Reliable Method ◽  
Fiber Diameter ◽  
Quantitative Agreement ◽  
One Dimension ◽  
Fiber Axis ◽  
Two Dimensional ◽  
Fiber Density ◽  
Variable Diameter ◽  
Freeze Dried ◽  
Expected Values

Although there is general agreement that Inactive chromosome fibers consist of helically packed nucleosomes, the pattern of packing is still undetermined. Only one of the proposed models, the crossed-linker model, predicts a variable diameter dependent on the length of DNA between nucleosomes. Measurements of the fiber diameter of negatively-stained and frozen- hydrated- chromatin from Thyone sperm (87bp linker) and Necturus erythrocytes (48bp linker) have been previously reported from this laboratory. We now introduce a more reliable method of measuring the diameters of electron images of fibrous objects. The procedure uses a modified version of the computer program TOTAL, which takes a two-dimensional projection of the fiber density (represented by the micrograph itself) and projects it down the fiber axis onto one dimension. We illustrate this method using high contrast, in-focus STEM images of TMV and chromatin from Thyone and Necturus. The measured diameters are in quantitative agreement with the expected values for the crossed-linker model for chromatin structure

Effect of Glycosaminoglycans on Thrombin- and Atroxin-Induced Fibrin Assembly and Structure

1989 ◽  
Vol 62 (04) ◽  
pp. 1057-1061 ◽  
Author(s):  
Marcus E Carr ◽  
Patrick L Powers
Keyword(s):  
Chondroitin Sulfate ◽  
Fiber Diameter ◽  
Lag Phase ◽  
Low Molecular Weight ◽  
Fibrin Gels ◽  
Fiber Size ◽  
Induced Changes ◽  
The Impact ◽  
Fiber Radius ◽  
Turbidity Increase

SummaryThis study was performed to quantitate the impact of several glycosaminoglycans (GAG) on fibrin assembly and structure. Gel formation was monitored as the increase in optical density at 633 nm subsequent to thrombin (2 NIH u/ml) or atroxin (0.10 mg/ml) addition to solutions of buffered fibrinogen (1 mg/ml) or plasma. Gel absorbance was measured as a function of wavelength (400 to 800 nm) and gel fiber diameter and mass/length ratio (μ) were calculated. Chondroitin sulfate A (CSA)shortened the lag phase, enhanced the maximal rate of turbidity increase, and increased the final gel turbidity of fibrin gels formed by thrombin or atroxin. CSA (16 mg/ml) increased fiber μ from 1.3 to 3.1 × 1013 dalton/cm and fiber radius from 6.0 to 8.6 × 10-6 cm in thrombin-induced gels. μ increased from 0.7 to 2.7 × 1013 dalton/cm and fiber radius from 4 to 7.8 × 10-6 cm for atroxin-induced gels. Above 16 mg/ml, CSA caused fibrinogen precipitation in purified solutions but not in plasma. CSA inhibited thrombin-induced plasma clotting of plasma but effects in atroxin-mediated plasma gels paralleled those seen in purified solutions. Chondroitin sulfate B (CSB)-induced changes in fibrin were similar but slightly less dramatic than those seen with CSA. μ increased from 0.9 to 2.0 × 1013 dalton/cm for thrombin-induced fibrin gels and from 0.8 to 2.3 × 1013 dalton/cm for atroxininduced gels. Low molecular weight heparin (Mr = 5100) slowed fibrin assembly and reduced fiber size by 50% in thrombininduced gels. Changes in μ of atroxin-induced gels were much less pronounced (<20%). This study documents pronounced GAGinduced changes in fibrin structure which vary with GAG species and may mediate significant physiologic functions.

Clinical case of breast tumor relapse in domestic cat

2020 ◽  
pp. 29-32
Author(s):  
Viktor V. Grechko ◽  
◽  
Lyudmila F. Bodrova ◽  
Dmitriy K. Ovchinnikov ◽  
Keyword(s):  
Histological Examination ◽  
Breast Tumor ◽  
Abdominal Ultrasound ◽  
Liver Parenchyma ◽  
Mammary Glands ◽  
Blood Analysis ◽  
Domestic Cat ◽  
Biological Behavior ◽  
Breast Adenocarcinoma ◽  
Low Grade

Domestic shorthair 10-year-old cat, not sterilized, not vaccinated, feeding from the table. We went to the clinic with breast cancer. General and special research methods were performed: blood analysis, x-ray examination of the lungs and abdominal ultrasound. Based on anamnesis and clinical examination, the diagnosis was made: a malignant breast tumor. The operation was performed. The operating material is sent for histological examination. Chemotherapy was prescribed. After the fi rst chemotherapy and monitoring of the animal's condition, it was necessary to perform a second unilateral mastoectomy of the remaining mammary glands, but the animal's owners refused to perform the operation. Chemotherapy was performed twice. Re-applied, after a year and a half with a sharp deterioration in the General condition and the appearance of a new tumor on the non-removed mammary glands. The owners refused the necessary treatment and decided to euthanize the cat. At the autopsy, breast neoplasms are presented as tubercles of various sizes. There are pronounced signs of inflammation, ulceration and necrosis foci. In the chest cavity, the lungs are enlarged, there were single and multiple formations of white and brown color, round shape of different diameters, dense consistency. There is a large number of metastases in the liver parenchyma. The organ is enlarged in size, dark brown in color, irregularly colored, with an uneven (bumpy) surface. In General, there are many dense nodes of a round-oval shape of white color, of various diameters. Histological examination of the tumor revealed foci of necrosis, atypical glandular complexes with frequently occurring mitosis figures. This structure indicates a low-grade breast adenocarcinoma. In the lungs, there is an expansion of the alveoli and bronchioles, thinning and rupture of the interalveolar partitions. There is a complex of tumor cells. In the liver, there is a lack of structural units of the liver, hepatocytes disperse chaotically, liver triads do not have a clear localization, atrophy and necrosis are expressed. Metastases in the liver, various forms. In a cat, a breast tumor interpreted as an adenocarcinoma had different biological behavior. At the initial diagnosis-adenocarcinoma of medium differentiation, and a year and a half later-low-grade adenocarcinoma.

Association between expression of Ki-67, parafibromin, p27, and Rb protein and the biological behavior in parathyroid tumors

2013 ◽  
Author(s):  
Keiko Ohkuwa ◽  
Chie Masaki ◽  
Junko Akaishi ◽  
Akifumi Suzuki ◽  
Takashi Uruno ◽  
...  
Keyword(s):  
Biological Behavior ◽  
Ki 67 ◽  
Rb Protein ◽  
Parathyroid Tumors

A Possible Basis for Nondestructive Characterization of Ropes of Nylon 6

1997 ◽  
Vol 503 ◽  
Author(s):  
H. Jiang ◽  
M. K. Davis ◽  
R. K. Eby ◽  
P. Arsenovic
Keyword(s):  
Tensile Strength ◽  
Service Life ◽  
Fiber Diameter ◽  
Structural Parameters ◽  
Crystal Form ◽  
Nylon 6 ◽  
Remaining Service Life ◽  
Nondestructive Characterization ◽  
Fractional Content

ABSTRACTPhysical properties and structural parameters have been measured for ropes of nylon 6 as a function of the number of use operations. The fractional content of the α crystal form, sound velocity, birefringence, tensile strength and length all increase systematically and significantly with increasing the number of use operations. The fractional content of the γ crystal form and fiber diameter decrease with use. These trends indicate that the measurement of such properties and structural parameters, especially the length, provide a possible basis for establishing a reliable, rapid, and convenient nondestructive characterization method to predict the remaining service life of nylon 6 ropes.

Effects and Mechanisms of Anlotinib and Dihydroartemisinin Combination Therapy in Ameliorating Malignant Biological Behavior of Gastric Cancer Cells

2020 ◽  
Vol 21 ◽  
Author(s):  
Qiong Luo ◽  
Suyun Zhang ◽  
Donghuan Zhang ◽  
Rui Feng ◽  
Nan Li ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Cancer Cells ◽  
Molecular Mechanisms ◽  
Chorioallantoic Membrane ◽  
Cell Counting ◽  
Biological Behavior ◽  
Gastric Cancer Cells ◽  
Invasion And Migration ◽  
Apoptosis Related Protein ◽  
And Migration

Background: Gastric cancer(GC) is currently one of the major malignancies that threatens human lives and health. Anlotinib is a novel small-molecule that inhibits angiogenesis to exert anti-tumor effects. However, the function in gastric cancer is incompletely understood. Objective: The aim of the present study was to investigate the anti-tumor effects and molecular mechanisms of anlotinib combined with dihydroartemisinin (DHA) in SGC7901 gastric cancer cells. Method: Different concentrations of anlotinib and DHA were used to treat SGC7901 gastric cancer cells, after which cell proliferation was measured. Drug interactions of anlotinib and DHA were analyzed by the Chou-Talalay method with CompuSyn software. proliferation, apoptosis, invasion, migration, and angiogenesis were measured using the cell counting kit-8 (CCK8) assay, flow cytometry, Transwell invasion assays, scratch assays, and chicken chorioallantoic membrane (CAM) assays. proliferation-associated protein (Ki67), apoptosis-related protein (Bcl-2), and vascular endothelial growth factor A (VEGF-A) were quantified by Western bloting. Results: The combination of 2.5 μmol/L of anlotinib and 5 of μmol/L DHA was highly synergistic in inhibiting cell growth, significantly increased the apoptosis rate and suppressed obviously the invasion and migration capability and angiogenesis of gastric cancer cells. In addition, the expression levels of Ki67, Bcl-2, and VEGF-A, as well as angiogenesis, were significantly decreased in the Combination of drugs compared with in control and either drug alone. Conclusion: The combination of anlotinib and DHA showed synergistic antitumor activity, suggesting their potential in treating patients with gastric cancer.

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