scholarly journals Lignin-Stabilized Doxorubicin Microemulsions: Synthesis, Physical Characterization, and In Vitro Assessments

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 641 ◽  
Author(s):  
Abbas Rahdar ◽  
Saman Sargazi ◽  
Mahmood Barani ◽  
Sheida Shahraki ◽  
Fakhara Sabir ◽  
...  
Keyword(s):  
Colorimetric Assay ◽  
Drug Carrier ◽  
Membrane Integrity ◽  
Entrapment Efficiency ◽  
Scientific Basis ◽  
Colloidal Systems ◽  
Morphological Alterations ◽  
Cell Membrane Integrity ◽  
Drug Efficiency

Encapsulation of the chemotherapy agents within colloidal systems usually improves drug efficiency and decreases its toxicity. In this study, lignin (LGN) (the second most abundant biopolymer next to cellulose on earth) was employed to prepare novel doxorubicin (DOX)-loaded oil-in-water (O/W) microemulsions with the aim of enhancing the bioavailability of DOX. The droplet size of DOX-loaded microemulsion was obtained as ≈ 7.5 nm by dynamic light scattering (DLS) analysis. The entrapment efficiency (EE) % of LGN/DOX microemulsions was calculated to be about 82%. In addition, a slow and sustainable release rate of DOX (68%) was observed after 24 h for these microemulsions. The cytotoxic effects of standard DOX and LGN/DOX microemulsions on non-malignant (HUVEC) and malignant (MCF7 and C152) cell lines were assessed by application of a tetrazolium (MTT) colorimetric assay. Disruption of cell membrane integrity was investigated by measuring intracellular lactate dehydrogenase (LDH) leakage. In vitro experiments showed that LGN/DOX microemulsions induced noticeable morphological alterations and a greater cell-killing effect than standard DOX. Moreover, LGN/DOX microemulsions significantly disrupted the membrane integrity of C152 cells. These results demonstrate that encapsulation and slow release of DOX improved the cytotoxic efficacy of this anthracycline agent against cancer cells but did not improve its safety towards normal human cells. Overall, this study provides a scientific basis for future studies on the encapsulation efficiency of microemulsions as a promising drug carrier for overcoming pharmacokinetic limitations.

scholarly journals Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Chukwuebuka H. Ozoude ◽  
Chukwuemeka P. Azubuike ◽  
Modupe O. Ologunagba ◽  
Sejoro S. Tonuewa ◽  
Cecilia I. Igwilo
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Metformin Hydrochloride ◽  
Scanning Calorimetry ◽  
Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

scholarly journals DEVELOPMENT OF RITONAVIR LOADED NANOPARTICLES: IN VITRO AND IN VIVO CHARACTERIZATION

2018 ◽  
Vol 11 (3) ◽  
pp. 284
Author(s):  
Pravin S Patil ◽  
Shashikant C Dhawale
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Dissolution Rate ◽  
Drug Carrier ◽  
Entrapment Efficiency ◽  
Significant Rise ◽  
Scanning Calorimetry ◽  
In Vitro Drug Release

 Objective: The purpose of the present investigation was to develop a nanosuspension to improve dissolution rate and oral bioavailability of ritonavir.Methods: Extended-release ritonavir loaded nanoparticles were prepared using the polymeric system by nanoprecipitation technique. Further, the effect of Eudragit RL100 (polymeric matrix) and polyvinyl alcohol (surfactant) was investigated on particle size and distribution, drug content, entrapment efficiency, and in vitro drug release from nanosuspension where a strong influence of polymeric contents was observed. Drug-excipient compatibility and amorphous nature of drug in prepared nanoparticles were confirmed by Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction studies, respectively.Results: Hydrophobic portions of Eudragit RL100 could result in enhanced encapsulation efficiency. However, increase in polymer and surfactant contents lead to enlarged particle size proportionately as confirmed by transmission electron microscopy. Nanosuspension showed a significant rise in dissolution rate with complete in vitro drug release as well as higher bioavailability in rats compared to the pure drug.Conclusion: The nanoprecipitation technique used in present research could be further explored for the development of different antiretroviral drug carrier therapeutics.

scholarly journals Essential Oil Microcapsules Immobilized on Textiles and Certain Induced Effects

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2029 ◽  
Author(s):  
Miruna S. Stan ◽  
Laura Chirila ◽  
Alina Popescu ◽  
Denisa M. Radulescu ◽  
Diana E. Radulescu ◽  
...  
Keyword(s):  
Membrane Integrity ◽  
Dermal Fibroblasts ◽  
Cell Membrane Integrity ◽  
Textile Materials ◽  
Skin Cells ◽  
In Vitro Biocompatibility ◽  
Short Term Exposure ◽  
Before And After

In order to obtain textile materials with potential utility in the development of cosmetic textiles, this study examined the deposition by padding of rose and sage microcapsules on woven textile structures, with different fiber compositions (100% cotton and 50% cotton/50% polyester). Cationization of the textile materials was performed to enhance the degree of uptake the pf the microcapsules on the fabrics’ surface. A commercially acrylate-based binder was used to fix the microcapsules to the textile substrate and to improve the durability against external factors. The finished textile materials were characterized in terms of their physical-mechanical characteristics. The distribution of microcapsules on the fabrics surface before and after five washing cycles and 1000 abrasion cycles was investigated by scanning electron microscopy. The biocompatibility in terms of cell viability, cell membrane integrity and inflammation status of the functionalized fabrics was evaluated on CCD-1070Sk normal human dermal fibroblasts. The cell morphology was evaluated by F-actin staining using fluorescence microscopy and no significant changes were noticed after the incubation in the presence of fabrics compared with control. The in vitro biocompatibility evaluation on human skin cells confirmed the absence of cytotoxicity after the short-term exposure, supporting further in vivo use of these innovative textiles with improved properties.

scholarly journals Contribution of the band 3-ankyrin interaction to erythrocyte membrane mechanical stability

Blood ◽  
1991 ◽  
Vol 77 (7) ◽  
pp. 1581-1586 ◽  
Author(s):  
PS Low ◽  
BM Willardson ◽  
N Mohandas ◽  
M Rossi ◽  
S Shohet
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Mechanical Stability ◽  
Membrane Integrity ◽  
Membrane Skeleton ◽  
Band 3 ◽  
Cell Membrane Integrity ◽  
The Face ◽  
Cell Stability

Abstract In an effort to evaluate the role of the band 3-ankyrin linkage in maintenance of red blood cell membrane integrity, solution conditions were sought that would selectively dissociate the band 3-ankyrin linkage, leaving other membrane skeletal interactions intact. For this purpose erythrocytes were equilibrated overnight in nutrient-containing buffers at a range of elevated pHs and then examined for changes in mechanical stability and membrane skeletal composition. Band 3 was found to be released from interaction with the membrane skeleton over a pH range (8.4 to 9.5) that was observed to dissociate the band 3- ankyrin interaction in vitro. In contrast, all other membrane skeletal associations appeared to remain intact up to pH 9.3, after which they were also seen to dissociate. Whereas hemolysis of mechanically unstressed cells did not begin until approximately pH 9.3, where the membrane skeletons began to disintegrate, enhanced fragmentation of shear stressed membranes was seen to begin near pH 8, where band 3 dissociation was first observed. Furthermore, the shear-induced fragmentation rate was found to reach a maximum at pH 9.4, ie, where band 3 dissociation was essentially complete. Based on these correlations, we hypothesize that the band 3-ankyrin linkage of the membrane skeleton to the lipid bilayer is essential for red blood cell stability in the face of mechanical distortion but not for cellular integrity in the absence of mechanical stress.

scholarly journals Two Polyketides Produced by Endophytic Penicillium citrinum DBR-9 From Medicinal Plant Stephania kwangsiensis and Their Antifungal Activity Against Plant Pathogenic Fungi

2019 ◽  
Vol 14 (5) ◽  
pp. 1934578X1984679 ◽  
Author(s):  
Haiyu Luo ◽  
Zhen Qing ◽  
Yecheng Deng ◽  
Zhiyong Deng ◽  
Xia’an Tang ◽  
...  
Keyword(s):  
Medicinal Plant ◽  
Membrane Integrity ◽  
Pathogenic Fungi ◽  
Significant Inhibition ◽  
Penicillium Citrinum ◽  
Plant Pathogenic Fungi ◽  
Fungal Cell ◽  
Cell Membrane Integrity ◽  
Chinese Medicinal Plant

Endophytic fungi, especially those found in medicinal plants, are widely studied as producers of secondary metabolites of biotechnological interest. In this study, on the basis of an activity-directed isolation method and spectroscopic analysis, two active polyketides, citrinin (1) and emodin (2), were isolated and identified from the fermentation of the endophytic fungus Penicillium citrinum DBR-9. This fungus was isolated from the root tubers of the traditional Chinese medicinal plant Stephania kwangsiensis. In vitro antifungal assay showed that the two polyketides displayed significant inhibition on hypha growth of tested plant pathogenic fungi with IC50 values ranging from 3.1 to 123.1 μg/mL and 3.0 to 141.0 μg/mL, respectively. In addition, the mechanism of the effects of emodin (2) on the pathogen revealed it could affect the colony morphology, destroy cell membrane integrity, and influence the protein synthesis of the tested fungal cell. This work is the first report of two polyketides-producing endophytic P. citrinum DBR-9 from the medicinal plant S. kwangsiensis. Our results present new opportunities to deeply understand the potential of these two polyketides as natural antifungal agents to control phytopathogens in agriculture.

scholarly journals Osteoblasts Growth Behaviour on Bio-Based Calcium Carbonate Aragonite Nanocrystal

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Abdullahi Shafiu Kamba ◽  
Zuki Abu Bakar Zakaria
Keyword(s):  
Calcium Carbonate ◽  
Fluorescent Microscopy ◽  
Membrane Integrity ◽  
Biological Response ◽  
Cellular Interactions ◽  
Cell Membrane Integrity ◽  
Native Bone ◽  
Composition Structure ◽  
Stimulate Osteoblast Differentiation

Calcium carbonate (CaCO3) nanocrystals derived from cockle shells emerge to present a good concert in bone tissue engineering because of their potential to mimic the composition, structure, and properties of native bone. The aim of this study was to evaluate the biological response of CaCO3nanocrystals on hFOB 1.19 and MC3T3 E-1 osteoblast cellsin vitro. Cell viability and proliferation were assessed by MTT and BrdU assays, and LDH was measured to determine the effect of CaCO3nanocrystals on cell membrane integrity. Cellular morphology was examined by SEM and fluorescence microscopy. The results showed that CaCO3nanocrystals had no toxic effects to some extent. Cell proliferation, alkaline phosphatase activity, and protein synthesis were enhanced by the nanocrystals when compared to the control. Cellular interactions were improved, as indicated by SEM and fluorescent microscopy. The production of VEGF and TGF-1 was also affected by the CaCO3nanocrystals. Therefore, bio-based CaCO3nanocrystals were shown to stimulate osteoblast differentiation and improve the osteointegration process.

Soluble CD14 Protects Human Lymphocytes from Apoptosis

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2566-2566
Author(s):  
Elizabeth Naparstek ◽  
Benjamin Sredni ◽  
Eti Zigman ◽  
Gali Senyor ◽  
Boris Tartakovsky
Keyword(s):  
Human Peripheral Blood ◽  
Protective Efficacy ◽  
Human Lymphocytes ◽  
Membrane Integrity ◽  
Peripheral Blood Lymphocytes ◽  
Apoptotic Cells ◽  
Soluble Cd14 ◽  
Apoptotic Pathway ◽  
Cell Membrane Integrity

Abstract CD14, a 56 Kd glycoprotein, typically present on myeloid cells, has been traditionally associated with innate immunity and pattern recognition. Recently its membrane bound form has been shown to be involved in apoptosis, as a tethering receptor for apoptotic cells on the surface of phagocytes-in this case with the purpose of removing apoptotic cells, and also as a surface molecule involved in protection from apoptosis of monocytes, neutrophils and recently on enterocytes, challenged with LPS. Our aim was to evaluate the possible involvement of the soluble CD14 in the apoptotic pathway of human lymphocytes. Methods: Freshly obtained human peripheral blood lymphocytes were cultured in vitro with gliotoxin, an apoptotic inducer. Human recombinant CD14 was added to the culture at physiological concentrations (10μg/ml-0.5 μg/ml) and apoptosis was assessed by cell membrane integrity using 7AAD, mitochondrial membrane potential by DiOC6(3) and cytoplasm shrinkage by cell size scatter analysis. Results: Using DiOC6(3) we were able to show that human lymphocytes cultured in the presence of gliotoxin contained 63.8%±21 apoptotic cells, as opposed to 12.2%±11.5 in control cultures. Addition of recombinant human CD14 at a concentration of 10 mg/ml neutralized the apoptotic effect of gliotoxin back to 20.2%±10 (p<0.003). This inhibitory effect was blocked by CD14-specific monoclonal antibodies, but not by control antibodies. We then identified and synthesized the fragment within the CD14 molecule that was responsible for this apoptosis protective effect, and demonstrated its comparable protective efficacy in vitro as shown in figure 1. The figure clearly reveals that this specific peptide, as opposed to the scrambled peptide, protected the lymphocytes form apoptosis, similarly to the full CD14 protein. Same results were obtained using 7AAD and cytoplasm shrinkage. Conclusion: Our data thus suggest that circulating CD14 may play an important role in the prevention of apoptosis of lymphocytes and perhaps of other cells. Figure Figure

Assessment of changes in sperm cell membrane integrity occurring during the storage of semen from genetically different males using two diagnostic methods

2014 ◽  
Vol 94 (4) ◽  
pp. 601-606 ◽  
Author(s):  
Anna Wysokińska ◽  
Stanislaw Kondracki
Keyword(s):  
Cell Membrane ◽  
Sperm Cell ◽  
Cell Membranes ◽  
Intact Cell ◽  
Membrane Integrity ◽  
Diagnostic Methods ◽  
Cell Membrane Integrity ◽  
Staining Methods ◽  
Breed Crosses

Wysokińska, A. and Kondracki, S. 2014. Assessment of changes in sperm cell membrane integrity occurring during the storage of semen from genetically different males using two diagnostic methods. Can. J. Anim. Sci. 94: 601–606. The present study was carried out to assess changes in sperm cell membrane integrity occurring during the storage of semen collected from genetically different domestic male pigs. The study was aimed at assessing differences in the course of changes in the integrity of cell membranes in spermatozoa produced by males with different degrees of genetic diversity (pure-bred males, two-breed hybrids and multi-breed crosses) and testing the usefulness of two methods of sperm cell membrane integrity evaluation, based on material collected from genetically different males. The experiments were conducted on 56 ejaculates collected from 28 domestic male pigs. The examination of sperm cell membrane integrity was performed three times for each ejaculate, i.e., after 1 h, after 24 h and after 48 h from collection. The preparations for analysing cell membrane integrity were made using two methods: the SYBR 14/PI method and the eosin–nigrosin method. It was found that both SYBR 14/PI and eosin–nigrosin staining methods make it possible to successfully assess the integrity of the plasma membrane of domestic pig sperm cells under in vitro conditions. Hybrid pig spermatozoa, especially those from multi-breed crosses, better retain the integrity of their plasmalemmas than the spermatozoa of pure-bred boars. The ejaculates of Hypor cross-breed boars assessed after 1, 24 and 48 h of storage contain more spermatozoa with intact cell membranes than the ejaculates of pure-bred Duroc and Pietrain boars. The ejaculates of Hypor boars also show fewer decaying spermatozoa than those produced by pure-bred boars.

scholarly journals Altering the Proclivity towards Daptomycin Resistance in Methicillin-Resistant Staphylococcus aureus Using Combinations with Other Antibiotics

2012 ◽  
Vol 56 (10) ◽  
pp. 5046-5053 ◽  
Author(s):  
Andrew D. Berti ◽  
Justine E. Wergin ◽  
Gary G. Girdaukas ◽  
Scott J. Hetzel ◽  
George Sakoulas ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Cell Membrane ◽  
Membrane Integrity ◽  
Wall Thickening ◽  
Methicillin Resistant ◽  
Content Type ◽  
Cell Membrane Integrity ◽  
Cell Membrane Fluidity

ABSTRACTDaptomycin (DAP) is increasingly used as a part of combination therapy, particularly in complex methicillin-resistantStaphylococcus aureus(MRSA) infections. While multiple studies have reported the potential for synergy between DAP and adjunctive anti-infectives, few have examined the influence of adjunctive therapy on the emergence of DAP resistance. This study examined eight adjunctive antimicrobial combinations with DAPin vitroand the emergence of DAP resistance over time (up to 4 weeks) using clinical isolates of DAP-susceptible MRSA (MIC, 0.5 μg/ml) in which DAP resistance subsequently developed during patient therapy (MIC, 3 μg/ml). In addition to DAP susceptibility testing, selected strains were examined for phenotypic changes associated with DAP resistance, including changes to cell wall thickness (CWT) and cell membrane alterations. The addition of either oxacillin or clarithromycin in medium containing DAP significantly inhibited the development of DAP resistance through the entirety of the 4-week exposure (10- to 32-fold MIC reduction from that of DAP alone). Combinations with rifampin or fosfomycin were effective in delaying the emergence of DAP resistance through the end of week one only (week one MIC, 0.5 μg/ml; week four MIC, 24 μg/ml). Cell wall thickening was observed for all antibiotic combinations regardless of their effect on the DAP MIC (14 to 70% increase in CWT), while changes in cell membrane fluidity were variable and treatment dependent. DAP showed reduced activity against strains with DAP MICs of 1 to 12 μg/ml, but cell membrane integrity was still disrupted at concentrations achieved with doses greater than 10 mg/kg of body weight. The emergence of DAP resistance in MRSA is strongly influenced by the presence of subinhibitory concentrations of adjunctive antimicrobials. These data suggest that combining DAP with oxacillin or clarithromycin may delay the development of DAP resistance in cases requiring prolonged antibiotic therapy.

Glucose enhancement of transcellular calcium transport in the intestine

1988 ◽  
Vol 255 (3) ◽  
pp. G339-G345 ◽  
Author(s):  
K. M. Carroll ◽  
R. J. Wood ◽  
E. B. Chang ◽  
I. H. Rosenberg
Keyword(s):  
Calcium Transport ◽  
Calcium Uptake ◽  
Calcium Absorption ◽  
Membrane Integrity ◽  
Calcium Flux ◽  
Calcium Efflux ◽  
Cell Membrane Integrity ◽  
Active Calcium ◽  
Altered Cell

Glucose stimulates calcium transport in vitro in rat duodenal tissue and isolated enterocytes. Under short-circuited conditions, glucose increased mucosal to serosal calcium flux (JCa(m----s)) without altering serosal to mucosal calcium flux (JCa(s----m)) in the duodenum, the primary site of active calcium absorption in the rat small intestine. The half-maximal dose (ED50) of the glucose stimulatory effect was less than 1 mM, and an increase in JCa(m----s) of 80% over control was seen at a glucose concentration of 50 mM. Glucose did not increase calcium flux in the ileum where active calcium absorption is minimal. Glucose stimulated net calcium uptake by 35% in isolated duodenal enterocytes. Glucose did not alter calcium efflux from preloaded enterocytes suspended in calcium-free buffer. Glucose enhancement of net calcium uptake in enterocytes was not caused by altered cell membrane integrity or functional viability. The nonmetabolizable glucose analogue alpha-methylglucoside did not stimulate calcium transport. Our findings suggest that glucose can stimulate intestinal calcium absorption, at least partially, by enhancing transcellular calcium transport and that cellular glucose metabolism is necessary for stimulation of this route of calcium transport.

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