Exploring the Critical Factors Limiting Polyaniline Biocompatibility

Today, the application of polyaniline in biomedicine is widely discussed. However, information about impurities released from polyaniline and about the cytotoxicity of its precursors aniline, aniline hydrochloride, and ammonium persulfate are scarce. Therefore, cytotoxicity thresholds for the individual precursors and their combinations were determined (MTT assay) and the type of cell death caused by exposition to the precursors was identified using flow-cytometry. Tests on fibroblasts revealed higher cytotoxicity of ammonium persulfate than aniline hydrochloride. Thanks to the synergic effect, both monomers in combination enhanced their cytotoxicities compared with individual substances. Thereafter, cytotoxicity of polyaniline doped with different acids (sulfuric, nitric, phosphoric, hydrochloric, and methanesulfonic) was determined and correlated with impurities present in respective sample (HPLC). The lowest cytotoxicity showed polyaniline doped with phosphoric acid (followed by sulfuric, methanesulfonic, and nitric acid). Cytotoxicity of polyaniline was mainly attributed to the presence of residual ammonium persulfate and low-molecular-weight polar substances. This is crucial information with respect to the purification of polyaniline and production of its cytocompatible form.

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Molecular weight determines the frequency of delayed type hypersensitivity reactions to heparin and synthetic oligosaccharides

Thrombosis and Haemostasis ◽

10.1160/th05-05-0318 ◽

2005 ◽

Vol 94 (12) ◽

pp. 1265-1269 ◽

Cited By ~ 34

Author(s):

Susanne Alban ◽

Roland Kaufmann ◽

Edelgard Lindhoff-Last ◽

Wolf-Henning Boehncke ◽

Ralf J. Ludwig ◽

...

Keyword(s):

Molecular Weight ◽

Heparin Therapy ◽

Delayed Type Hypersensitivity ◽

Published Data ◽

Low Molecular Weight ◽

Hypersensitivity Reactions ◽

Type Iv ◽

Total Data ◽

The Individual

SummaryEczematous lesions, resulting from type IV sensitizations are well-known and relatively frequent cutaneous adverse effects of s.c. heparin therapy. If anticoagulation is further required intravenous heparin, heparinoids or lepirudin may be used as a substitute. However, these alternatives are not optimal in terms of practicability and/or safety-profiles. As molecular weight of different heparin preparations has repetitively been implied to determine the frequency of sensitization, we hypothesized, that due to its low molecular weight the pentasaccharide fondaparinux may provide a practicable and safe anticoagulant therapy in patients with delayed type hypersensitivity reactions (DTH) to heparin and other oligosaccharides. To test this concept, patients referred for diagnosis of cutaneous reactions after s.c. anticoagulant treatment underwent a series of in vivo skin allergyand challenge-tests with unfractionated heparin, a series of low molecular weight heparins (nadroparin, dalteparin, tinzaparin, enoxaparin and certoparin), the heparinoid danaparoid and the synthetic pentasaccharide fondaparinux. In total, data from twelve patients was evaluated. In accordance with previously published data, we report a high crossreactivity among heparins and heparinoids. In contrast – and in support of our initial hypothesis – sensitization towards the synthetic pentasaccharide fondaparinux was rarely observed. Plotting the cumulative incidence against the determined molecular weight of the individual anticoagulant preparations, shows that molecular weight generally is a key determinant of sensitization towards heparins and other oligosaccharides (r2=0.842, p=0.009). Hence, fondaparinux may be used as a therapeutic alternative in patients with cutaneous DTH relations towards heparin and other polysaccharides.

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CD80 Expression Correlates with IL-6 Production in THP-1-Like Macrophages Costimulated with LPS and Dialyzable Leukocyte Extract (Transferon®)

Journal of Immunology Research ◽

10.1155/2019/2198508 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Alexis P. Jiménez-Uribe ◽

Hugo Valencia-Martínez ◽

Gregorio Carballo-Uicab ◽

Luis Vallejo-Castillo ◽

Emilio Medina-Rivero ◽

...

Keyword(s):

Molecular Weight ◽

Flow Cytometry ◽

Viral Infections ◽

Surface Expression ◽

Low Molecular Weight ◽

Activated Macrophages ◽

Therapeutic Properties ◽

And Function ◽

Complex Drug ◽

Stimulation Of

Transferon® is a complex drug based on a mixture of low molecular weight peptides. This biotherapeutic is employed as a coadjuvant in clinical trials of several diseases, including viral infections and allergies. Given that macrophages play key roles in pathogen recognition, phagocytosis, processing, and antigen presentation, we evaluated the effect of Transferon® on phenotype and function of macrophage-like cells derived from THP-1 monocytes. We determined the surface expression of CD80 and CD86 by flow cytometry and IL-1β, TNF-α, and IL-6 levels by ELISA. Transferon® alone did not alter the steady state of PMA-differentiated macrophage-like THP-1 cells. On the contrary, simultaneous stimulation of cells with Transferon® and LPS elicited a significant increase in CD80 (P≤0.001) and CD86 (P≤0.001) expression, as well as in IL-6 production (P≤0.05) compared to the LPS control. CD80 expression and IL-6 production exhibited a positive correlation (r=0.6, P≤0.05) in cells exposed to Transferon® and LPS. Our results suggest that the administration of Transferon® induces the expression of costimulatory molecules and the secretion of cytokines in LPS-activated macrophages. Further studies are necessary to determine the implication of these findings in the therapeutic properties of Transferon®.

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Selective Suppression of Cell Growth and Programmed Cell Death-Ligand 1 Expression in HT1080 Fibrosarcoma Cells by Low Molecular Weight Fucoidan Extract

Marine Drugs ◽

10.3390/md17070421 ◽

2019 ◽

Vol 17 (7) ◽

pp. 421 ◽

Cited By ~ 3

Author(s):

Kiichiro Teruya ◽

Yoshihiro Kusumoto ◽

Hiroshi Eto ◽

Noboru Nakamichi ◽

Sanetaka Shirahata

Keyword(s):

Molecular Weight ◽

Cell Death ◽

Programmed Cell Death ◽

Cancer Cells ◽

Biological Activities ◽

Immune Surveillance ◽

Selective Inhibition ◽

Low Molecular Weight ◽

Fibrosarcoma Cells ◽

Self Protection

Low molecular weight fucoidan extract (LMF), prepared by an abalone glycosidase digestion of a crude fucoidan extracted from Cladosiphon novae-caledoniae Kylin, exhibits various biological activities, including anticancer effect. Various cancers express programmed cell death-ligand 1 (PD-L1), which is known to play a significant role in evasion of the host immune surveillance system. PD-L1 is also expressed in many types of normal cells for self-protection. Previous research has revealed that selective inhibition of PD-L1 expressed in cancer cells is critical for successful cancer eradication. In the present study, we analyzed whether LMF could regulate PD-L1 expression in HT1080 fibrosarcoma cells. Our results demonstrated that LMF suppressed PD-L1/PD-L2 expression and the growth of HT1080 cancer cells and had no effect on the growth of normal TIG-1 cells. Thus, LMF differentially regulates PD-L1 expression in normal and cancer cells and could serve as an alternative complementary agent for treatment of cancers with high PD-L1 expression.

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Programmed Cell Death in Human Ovary Is a Function of Follicle and Corpus Luteum Status*

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.82.9.4191 ◽

1997 ◽

Vol 82 (9) ◽

pp. 3148-3155

Author(s):

Wei Yuan ◽

Linda C. Giudice

Keyword(s):

Molecular Weight ◽

Cell Death ◽

Programmed Cell Death ◽

Corpus Luteum ◽

Dna Fragmentation ◽

Low Molecular Weight ◽

Corpora Lutea ◽

Positive Staining ◽

Human Ovary ◽

Dna Laddering

Abstract Although extensive investigation on follicular apoptosis (programmed cell death) has been conducted in the infraprimate ovary, there is little information regarding apoptosis and its relationship to follicular status in the human. In this study, apoptosis was investigated in 116 human ovarian follicles (primordial to dominant) and 5 corpora lutea from a total of 27 premenopausal women. Follicles and corpora lutea were evaluated for the presence of DNA fragmentation, characteristic of apoptosis, by two methods: in situ hybridization using 3′ end-labeling of DNA with digoxigenin-labeled nucleotides and subsequent digoxigenin antibody and peroxidase staining, and/or biochemical analysis of low molecular weight DNA laddering. Follicle functional status was evaluated by determining follicle sizes and follicular fluid androgen/estrogen (A/E) ratios. No apoptosis was observed in 67 primordial, primary, or secondary follicles. Positive staining for DNA fragmentation was found in a few granulosa cells in 0.1- to 2-mm follicles, whereas abundant staining in granulosa was detected in 2.1- to 9.9-mm follicles. In contrast, no DNA fragmentation was detected in dominant follicles (10–16 mm). The frequency of apoptosis in follicles was calculated to be 37% in 0.1- to 2-mm follicles, 50% in 2.1- to 5-mm follicles, and 27% in 5.1- to 9.9-mm follicles. Abundant low molecular weight DNA laddering was only found in androgen-dominant follicles and not in estrogen-dominant follicles. Positive staining for DNA fragmentation and low molecular weight DNA laddering were observed in degenerating but not healthy-appearing corpora lutea. In the former, DNA fragmentation was found primarily in large luteal cells. These data suggest that follicular atresia in human ovary results from normal programmed cell death and primarily occurs in the granulosa cell layers of the early antral and <10-mm antral follicles primarily. Furthermore, because apoptosis occurs as early as the 200-mm stage, follicle selection may begin as early as the initial formation of the antrum. The results also suggest that degeneration of the corpus luteum occurs by apoptotic mechanisms.

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In Vitro Evaluation of the Effects of Cadmium on Endocytic Uptakes of Proteins into Cultured Proximal Tubule Epithelial Cells

Toxics ◽

10.3390/toxics8020024 ◽

2020 ◽

Vol 8 (2) ◽

pp. 24

Author(s):

Hitomi Fujishiro ◽

Hazuki Yamamoto ◽

Nobuki Otera ◽

Nanae Oka ◽

Mei Jinno ◽

...

Keyword(s):

Molecular Weight ◽

Flow Cytometry ◽

Tubular Reabsorption ◽

In Vitro Assay ◽

Low Molecular Weight ◽

S2 Cells ◽

Vitro Assay ◽

Renal Tubular ◽

Low Molecular Weight Proteins

Cadmium (Cd) is an environmental pollutant known to cause dysfunctions of the tubular reabsorption of biomolecules in the kidney. Elevated levels of urinary excretion of low-molecular-weight proteins such as β2-microglobulin (β2-MG) have been used as an indicator of Cd-induced renal tubular dysfunctions. However, very few studies have examined the direct effects of Cd on the reabsorption efficiency of proteins using cultured renal cells. Here, we developed an in vitro assay system for quantifying the endocytic uptakes of fluorescent-labeled proteins by flow cytometry in S1 and S2 cells derived from mouse kidney proximal tubules. Endocytic uptakes of fluorescent-labeled albumin, transferrin, β2-MG, and metallothionein into S1 cells were confirmed by fluorescence imaging and flow cytometry. The exposure of S1 and S2 cells to Cd at 1 and 3 µM for 3 days resulted in significant decreases in the uptakes of β2-MG and metallothionein but not in those of albumin or transferrin. These results suggest that Cd affects the tubular reabsorption of low-molecular-weight proteins even at nonlethal concentrations. The in vitro assay system developed in this study to evaluate the endocytic uptakes of proteins may serve as a useful tool for detecting toxicants that cause renal tubular dysfunctions.

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Oligonol, a Low Molecular Weight Polyphenol, Enhances Apoptotic Cell Death in Ovarian Cancer Cells via Suppressing NF-κB Activation

Nutrition and Cancer ◽

10.1080/01635581.2018.1557215 ◽

2019 ◽

Vol 71 (1) ◽

pp. 141-148

Author(s):

Miseon Kim ◽

Wook Ha Park ◽

Seul Lee ◽

Dong Hoon Suh ◽

Kidong Kim ◽

...

Keyword(s):

Ovarian Cancer ◽

Molecular Weight ◽

Cell Death ◽

Cancer Cells ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Ovarian Cancer Cells ◽

Low Molecular Weight

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Clinical and Laboratory Validation of the 2nd International Standard of Low Molecular Weight Heparin (IS 2003-01/608) in the Anti-Xa, Anti-LIA Heptest and Prothrombinase Induced Clotting (PiCT) Tests.

Blood ◽

10.1182/blood.v106.11.4147.4147 ◽

2005 ◽

Vol 106 (11) ◽

pp. 4147-4147

Author(s):

D. Hoppensteadt ◽

W. Jeske ◽

D. Fareed ◽

F. Baltasar ◽

J. M. Walenga ◽

...

Keyword(s):

Molecular Weight ◽

International Standards ◽

Clinical Monitoring ◽

Low Molecular Weight ◽

Therapeutic Trial ◽

Global Test ◽

International Standard ◽

Assay Methods ◽

The Individual ◽

Concentration Curves

Abstract Background: Because of the relative insensitivity of the global clot based assays such as the activated partial thromboplastin time (APTT), the low molecular weight heparins (LMWHs) are potency evaluated/optimized in the anti-Xa (AXa) and heptest. A new clot based assay namely, prothrombin induced clotting time (PiCT) is sensitive to the anticoagulant effects of LMWHs and related drugs. As the LMWHs are standardized using the anti-Xa methods, using the International Standards, this study was designed to cross validate the 2nd International Standard for LMWHs(NIBSC 01/608) in various assay methods. Methods: Commercially available LMWHs, Dalteparin (D), Enoxaparin (E), Tinzaparin (T) and the 1st International Standard (85/600) were crossed referenced against the 2nd International Standard (NIBSC 01/608) using an amidolytic AXa method. Each of these LMWHs were compared in the AXa, adjusted concentration range of 0–1.0 U/ml using the Heptest, AXa, AIIa and PiCT. In addition plasma samples from patients receiving a LMWH, E for therapeutic and interventional purposes were measured using various tests. Results: The AXa potency adjusted LMWHs (D, E, and T) and 1st International Standard provided superimposable concentration curves in the amidolytic AXa assays. However marked differences in the heptest and PiCT were noted. Major differences were noted in the AIIA levels, even between the two International standards. When patients samples (n=75) from a therapeutic trial (1.0 mg/kg BID/SC) were evaluated, assay based differences were further amplified. The amidolytic AXa assay consistently measured higher AXa levels. When the two standards were cross-referenced with one another in different assays, major differences were noted in the clot-based assays. Even in the AXa assay at equivalent AXa levels, differences were obvious. Conclusions: These results suggest that both of the International Standards of LMWH are valid for only the cross standardization of the AXa activities of LMWHs. If any of the other methods were used, significantly different results were obtained with each of the individual LMWHs. Thus, the 2nd International Standard should only be used for amidolytic AXa assay for potency referencing purposes. Moreover, the stated potency of the 2nd Internation Standard may need to be readjusted against the 1st Standard to obtain valid results. These standards are of limited value in the clinical monitoring of LMWHs. It is therefore proposed that each of the LMWHs should be cross referenced by its own standard and the clinical monitoring of these drugs should only be carried out utilizing the specific drug used in a given patient. The PiCT test offers a global test which is capable of monitoring the effects of all components of heparins regardless of their affinity to serpines. Moreover, the effect of TFPI released on clotting processes is also measured. Thus, the PiCT test provides a physiologically relevant anticoagulant index.

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Thrombin Generation Is a Sensitive Measure of Low Molecular Weight Heparin Anticoagulant Activity.

Blood ◽

10.1182/blood.v116.21.1099.1099 ◽

2010 ◽

Vol 116 (21) ◽

pp. 1099-1099

Author(s):

Alexander Gatt ◽

Anne Riddell ◽

Lesley Lanning ◽

Saman Aghighi ◽

Pamala Kanagasapathy ◽

...

Keyword(s):

Molecular Weight ◽

Thrombin Generation ◽

Conflicts Of Interest ◽

Anticoagulant Activity ◽

Coagulation Cascade ◽

Low Molecular Weight ◽

Acute Thrombosis ◽

Coagulation Proteins ◽

Risk Patients ◽

The Individual

Abstract Abstract 1099 Current guidelines recommend monitoring of low molecular weight heparins (LMWHs) using the anti-Xa assay in high risk patients like those with renal impairment, pregnancy or overweight and in children. However, it is well accepted that this test does not accurately predict the anticoagulant effect of these drugs1. This is understandable since the various LMWHs available affect the coagulation cascade in different ways relative to their different molecular structure. Notoriously, the larger LMWHs like Tinzaparin have a higher anti-IIa to anti-Xa ratio that is not detected by the anti-Xa assay. We hypothesized that thrombin generation (TG) is a better, more sensitive way how to monitor LMWH anticoagulant activity since it is a measure of the interplay of all coagulation proteins. Blood samples from patients with acute thrombosis, pregnancy and other conditions and having LMWH monitoring were analysed using a chromogenic anti-Xa assay and a TG assay as per Hemker et al2 together with a chromogenic anti-IIa and FVIII clotting assay (FVIII:C). A tissue factor trigger of 10pM Innovin was used for the TG experiments. Patient samples were divided into 2 groups: those on Tinzaparin (n=45) or Enoxaparin (n=39). There was no difference between the FVIII:C levels of the Tinzaparin and Enoxaparin groups (mean 250 vs 327IU/ml P>0.05). A higher lower mean anti-Xa and a higher mean anti-IIa level was achieved with Tinzaparin (0.48 vs 0.63 U/ml P= >0.05 for anti-Xa and 0.3 vs 0.15U/ml P=0.005 for anti-IIa respectively). The endogenous thrombin potential (ETP) was significantly lower with Tinzaparin than Enoxaparin despite a higher anti-Xa (705 vs 1216nM.min P=0.006). Linear regression analysing TG with anti-Xa of the two LMWHs shows that 1.0U/ml antiXa activity for Enoxaparin is as potent as 0.7U/ml Tinzaparin in suppressing TG to similar levels. Significant inter-individual variation in TG suppression was noted with both LMWHs. This study demonstrates that anti-Xa results achieved for different LMWHs do not have the same anticoagulant significance. Using TG, we achieved similar therapeutic anti-Xa levels as achieved from the individual LMWH clinical trials3. It is clear that TG is a better test to predict LMWH anticoagulant activity. This needs to be proven in clinical studies. 1. Baglin T et al British Journal of Haematol. 2006; 133(1): 19–34. 2. Hemker HC et al Pathophysiol Haemost Thromb, 33, 4-15. Boneu B and de Moorloose P. Semin Thromb Hemost 2001; 27(5): 519–522. Disclosures: No relevant conflicts of interest to declare.

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