Preparation of cultured astrocytes for x-ray microanalysis

Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1777 ◽  
Author(s):  
Jaeyong Kim ◽  
Huwon Kang ◽  
Hakjoon Choi ◽  
Ara Jo ◽  
Dooi-Ri Oh ◽  
...  

The leaves of Perilla frutescens var. acuta (PFA) are commonly used as a traditional medicine in Korea, Japan, and China. We previously showed that PFA attenuates eye fatigue by improving visual accommodation through a clinical study. However, detailed mechanisms and chemical compounds have not been studied. In this study, we analyzed the active compounds in an aqueous extract of PFA involved in ciliary muscle relaxation in vitro and in vivo. NMR and MS analyses showed that the PFA extract contained mainly luteolin-7-O-diglucuronide and apigenin-7-O-diglucuronide. The composition after freeze-drying and spray-drying was similar. Freeze-dried PFA (50 µg/mL, 100 µg/mL, and 200 µg/mL) increased nitric oxide and cGMP levels in ciliary muscle cells isolated from the eyes of rats. [Ca2+]i decreased in a dose-dependent manner. Furthermore, Sprague-Dawley rats treated with freeze-dried PFA (200 mg/kg, orally) showed significantly increased cGMP levels compared with the control group and irradiated with white light. Our results suggest that PFA extract has the potential to reduce eye fatigue by relaxing ciliary muscles.


2001 ◽  
Vol 7 (S2) ◽  
pp. 732-733
Author(s):  
Y. Fujii ◽  
N. Terada ◽  
T. Baba ◽  
H. Ueda ◽  
S. Ohno

It is well known that flowing erythrocytes in blood capillaries were morphologically changing in vivo, as observed by light microscopy. Recently, dynamic morphological changes of flowing mouse erythrocytes in large blood vessels and hepatic sinusoids were demonstrated by scanning (SEM) or transmission (TEM) electron microscopy with our “in vivo cryotechnique”. Moreover, human erythrocyte deformability was already studied under artificially jetting conditions at different pressures by using “in vivo cryotechnique”, followed by freeze-substitution method for SEM. in this study, we have analyzed elemental changes of each human erythrocyte at different jetting pressures by “in vivo cryotechnique” combined with SEM for X-ray microanalysis.Human blood was collected with heparin-coated syringes, divided into two groups and kept at 4°C and 36°C. They were directly jetted into isopentane-propane cryogen (-193°C) through tubes (21 gauge) at different pressures (0-220mmHg) (Fig.la). The frozen blood samples were freeze-dried (4-6×10-7torr,-95°C,24h) in Eiko FD-3AS apparatus (Eiko Engineering, Japan) (Fig. lb).


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


2020 ◽  
Vol 17 (3) ◽  
pp. 207-217
Author(s):  
Eman A. Hakeem ◽  
Galal M. El-Mahrouk ◽  
Ghada Abdelbary ◽  
Mahmoud H. Teaima

Background: Clopidogrel (CLP) suffers from extensive first pass metabolism results in a negative impact on its oral systemic bioavailability. Cubosomes are Lyotropic Liquid Crystalline (LLC) nano-systems comprising monoolein, a steric stabilizer and an aqueous system, it considered a promising carrier for different pharmaceutical compounds. Box-Behnken Design (BBD) is an efficient tool for process analysis and optimization skipping forceful treatment combinations. Objective: The study was designed to develop freeze-dried clopidogrel loaded LLC (cubosomes) for enhancement of its oral bioavailability. Methods: A 33 BBD was adopted, the studied independent factors were glyceryl monooleate (GMO lipid phase), Pluronic F127 (PL F127steric stabilizer) and polyvinyl alcohol powder (stabilizer). Particle Size (PS), Polydispersity Index (PDI) and Zeta Potential (ZP) were set as independent response variables. Seventeen formulae were prepared in accordance with the bottom up approach and in-vitro evaluated regarding PS, PDI and ZP. Statistical analysis and optimization were achieved using design expert software®, then the optimum suggested formula was prepared, in-vitro revaluated, freeze-dried with 3% mannitol (cryoprotectant), solid state characterized and finally packed in hard gelatin capsule for comparative in-vitro release and in-vivo evaluation to Plavix®. Results: Results of statistical analysis of each individual response revealed a quadratic model for PS and PDI where a linear model for ZP. The optimum suggested formula with desirability factor equal 0.990 consisting of (200 mg GMO, 78.15 mg PL F127 and 2% PVA). LC/MS/MS study confirmed significant higher C>max, AUC>0-24h and AUC>0-∞ than that of Plavix®. Conclusion: The results confirm the capability of developed carrier to overcome the low oral bioavailability.


Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4554
Author(s):  
Ralph-Alexandru Erdelyi ◽  
Virgil-Florin Duma ◽  
Cosmin Sinescu ◽  
George Mihai Dobre ◽  
Adrian Bradu ◽  
...  

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.


2021 ◽  
Vol 30 ◽  
pp. 096368972110354
Author(s):  
Eun-Jung Yoon ◽  
Hye Rim Seong ◽  
Jangbeen Kyung ◽  
Dajeong Kim ◽  
Sangryong Park ◽  
...  

Stamina-enhancing effects of human adipose derived stem cells (hADSCs) were investigated in young Sprague-Dawley rats. Ten-day-old male rats were transplanted intravenously (IV) or intracerebroventricularly (ICV) with hADSCs (1 × 106 cells/rat), and physical activity was measured by locomotor activity and rota-rod performance at post-natal day (PND) 14, 20, 30, and 40, as well as a forced swimming test at PND 41. hADSCs injection increased the moving time in locomotor activity, the latency in rota-rod performance, and the maximum swimming time. For the improvement of physical activity, ICV transplantation was superior to IV injection. In biochemical analyses, ICV transplantation of hADSCs markedly reduced serum creatine phosphokinase, lactate dehydrogenase, alanine transaminase, and muscular lipid peroxidation, the markers for muscular and hepatic injuries, despite the reduction in muscular glycogen and serum triglycerides as energy sources. Notably, hADSCs secreted brain-derived neurotrophic factor (BDNF) and nerve growth factor in vitro, and increased the level of BDNF in the brain and muscles in vivo. The results indicate that hADSCs enhance physical activity including stamina not only by attenuating tissue injury, but also by strengthening the muscles via production of BDNF.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii214-ii214
Author(s):  
Jenna Minami ◽  
Nicholas Bayley ◽  
Christopher Tse ◽  
Henan Zhu ◽  
Danielle Morrow ◽  
...  

Abstract Metabolic reprogramming is a hallmark of cancer, and malignant cells must acquire metabolic adaptations to fuel neoplastic progression. Mutations or changes in metabolic gene expression can impose nutrient dependencies in tumors, and even in the absence of metabolic defects, cancer cells can become auxotrophic for particular nutrients or metabolic byproducts generated by other cells in the tumor microenvironment (TME). Conventional cell lines do not recapitulate the metabolic heterogeneity of glioblastoma (GBM), while primary cultured cells do not account for the influences of the microenvironment and the blood brain barrier on tumor biology. Additionally, these systems are under strong selective pressure divergent from that in vivo, leading to reduced heterogeneity between cultured tumor cells. Here, we describe a biobank of direct-from-patient derived orthotopic xenografts (GliomaPDOX) and gliomaspheres that reveal a subset of gliomas that, while able to form in vivo, cannot survive in vitro. RNA sequencing of tumors that can form both in vivo and in vitro (termed “TME-Indifferent”) compared to that of tumors that can only form in vivo (termed “TME-Dependent”) revealed transcriptional changes associated with altered nutrient availability, emphasizing the unique metabolic programs impacted by the tumor microenvironment. Furthermore, TME-dependent tumors lack metabolic signatures associated with nutrient biosynthesis, thus indicating a potential dependency of these tumors on scavenging specific nutrients from the extracellular milieu. Collectively, these data emphasize the metabolic heterogeneity within GBM, and reveal a subset of gliomas that lack metabolic plasticity, indicating a potential brain-microenvironment specific metabolic dependency that can be targeted for therapy.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 825
Author(s):  
Saman Sargazi ◽  
Mohammad Reza Hajinezhad ◽  
Abbas Rahdar ◽  
Muhammad Nadeem Zafar ◽  
Aneesa Awan ◽  
...  

In this research, tin ferrite (SnFe2O4) NPs were synthesized via hydrothermal route using ferric chloride and tin chloride as precursors and were then characterized in terms of morphology and structure using Fourier-transform infrared spectroscopy (FTIR), Ultraviolet–visible spectroscopy (UV-Vis), X-ray power diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) method. The obtained UV-Vis spectra was used to measure band gap energy of as-prepared SnFe2O4 NPs. XRD confirmed the spinel structure of NPs, while SEM and TEM analyses disclosed the size of NPs in the range of 15–50 nm and revealed the spherical shape of NPs. Moreover, energy dispersive X-ray spectroscopy (EDS) and BET analysis was carried out to estimate elemental composition and specific surface area, respectively. In vitro cytotoxicity of the synthesized NPs were studied on normal (HUVEC, HEK293) and cancerous (A549) human cell lines. HUVEC cells were resistant to SnFe2O4 NPs; while a significant decrease in the viability of HEK293 cells was observed when treated with higher concentrations of SnFe2O4 NPs. Furthermore, SnFe2O4 NPs induced dramatic cytotoxicity against A549 cells. For in vivo study, rats received SnFe2O4 NPs at dosages of 0, 0.1, 1, and 10 mg/kg. The 10 mg/kg dose increased serum blood urea nitrogen and creatinine compared to the controls (P < 0.05). The pathology showed necrosis in the liver, heart, and lungs, and the greatest damages were related to the kidneys. Overall, the in vivo and in vitro experiments showed that SnFe2O4 NPs at high doses had toxic effects on lung, liver and kidney cells without inducing toxicity to HUVECs. Further studies are warranted to fully elucidate the side effects of SnFe2O4 NPs for their application in theranostics.


Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2223
Author(s):  
Manon Dominique ◽  
Nicolas Lucas ◽  
Romain Legrand ◽  
Illona-Marie Bouleté ◽  
Christine Bôle-Feysot ◽  
...  

CLPB (Caseinolytic peptidase B) protein is a conformational mimetic of α-MSH, an anorectic hormone. Previous in vivo studies have already shown the potential effect of CLPB protein on food intake and on the production of peptide YY (PYY) by injection of E. coli wild type (WT) or E. coli ΔClpB. However, until now, no study has shown its direct effect on food intake. Furthermore, this protein can fragment naturally. Therefore, the aim of this study was (i) to evaluate the in vitro effects of CLPB fragments on PYY production; and (ii) to test the in vivo effects of a CLPB fragment sharing molecular mimicry with α-MSH (CLPB25) compared to natural fragments of the CLPB protein (CLPB96). To do that, a primary culture of intestinal mucosal cells from male Sprague–Dawley rats was incubated with proteins extracted from E. coli WT and ΔCLPB after fragmentation with trypsin or after a heat treatment of the CLPB protein. PYY secretion was measured by ELISA. CLPB fragments were analyzed by Western Blot using anti-α-MSH antibodies. In vivo effects of the CLPB protein on food intake were evaluated by intraperitoneal injections in male C57Bl/6 and ob/ob mice using the BioDAQ® system. The natural CLPB96 fragmentation increased PYY production in vitro and significantly decreased cumulative food intake from 2 h in C57Bl/6 and ob/ob mice on the contrary to CLPB25. Therefore, the anorexigenic effect of CLPB is likely the consequence of enhanced PYY secretion.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shojiro Katoh ◽  
Atsuki Fujimaru ◽  
Masaru Iwasaki ◽  
Hiroshi Yoshioka ◽  
Rajappa Senthilkumar ◽  
...  

AbstractRegenerative medicine applications require cells that are not inflicted with senescence after in vitro culture for an optimal in vivo outcome. Methods to overcome replicative senescence include genomic modifications which have their own disadvantages. We have evaluated a three-dimensional (3D) thermo-reversible gelation polymer (TGP) matrix environment for its capabilities to reverse cellular senescence. The expression of senescence-associated beta-galactosidase (SA-βgal) by human chondrocytes from osteoarthritis-affected cartilage tissue, grown in a conventional two-dimensional (2D) monolayer culture versus in 3D-TGP were compared. In 2D, the cells de-differentiated into fibroblasts, expressed higher SA-βgal and started degenerating at 25 days. SA-βgal levels decreased when the chondrocytes were transferred from the 2D to the 3D-TGP culture, with cells exhibiting a tissue-like growth until 42–45 days. Other senescence associated markers such as p16INK4a and p21 were also expressed only in 2D cultured cells but not in 3D-TGP tissue engineered cartilage. This is a first-of-its-kind report of a chemically synthesized and reproducible in vitro environment yielding an advantageous reversal of aging of human chondrocytes without any genomic modifications. The method is worth consideration as an optimal method for growing cells for regenerative medicine applications.


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