Exploring Therapeutic Potential Of Nanocarrier Systems Against Breast Cancer.

PubMed

Kumar, Lalit; Baldi, Ashish; Verma, Shivani; Utreja, Puneet

2018-06-03

Breast cancer is most widely occurring non-cutaneous cancer in women. Treatment options available for breast cancer are limited and there are a number of toxicity concerns associated with them. Therefore, nanocarrier based approaches have been explored for breast cancer treatment. Nanocarriers implemented for breast cancer treatment are nanoliposomes, polymeric nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers, gold nanoparticles, dendrimers, and protein nanocages. Objective of this review was to explore the therapeutic efficacy of various nanocarrier systems against breast cancer. Existing literature regarding nanocarrier systems for breast cancer therapy was reviewed using Pubmed and Google Scholar. Nanocarriers may show prolonged circulation time of chemotherapeutic agent with efficient breast tumor targeting. Both active and passive targeting methodologies can be explored to target breast cancer cells using different nanocarriers. Targeted nanocarriers have the capability to reduce side effects caused by various conventional formulations used to treat breast cancer. Various nanocarriers listed above have shown their therapeutic potential in preclinical studies to treat breast cancer. Satisfactory clinical evaluation and scale up techniques can promote their entry into the pharmaceutical market in greater extent. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Vibrio parahaemolyticus CalR down regulates the thermostable direct hemolysin (TDH) gene transcription and thereby inhibits hemolytic activity.

PubMed

Zhang, Yiquan; Zhang, Ying; Gao, He; Zhang, Lingyu; Yin, Zhe; Huang, Xinxiang; Zhou, Dongsheng; Yang, Huiying; Yang, Wenhui; Wang, Li

2017-05-20

TDH, encoded by tdh gene, is a major virulent determinant of V. parahaemolyticus that controls various biological activities, such as hemolytic activity, cytotoxicity, and enterotoxicity. The hemolytic activity on Wagatsuma agar ascribed to TDH is called Kanagawa phenomenon (KP). All KP positive strains contain tdh1 and tdh2 genes, but tdh2 is predominantly responsible for KP. CalR is a regulatory protein that was originally identified as a repressor of swarming motility and T3SS1 gene expression in V. parahaemolyticus. In the present study, the regulation of tdh2 by CalR was investigated using a set of experiments including qRT-PCR, primer extension, LacZ fusion, hemolytic phenotype, EMSA, and DNase I footprinting assays. The results showed that His-CalR protected a single region from 224bp to 318bp upstream of tdh2 against DNase I digestion, and a transcriptional start site located at 42bp upstream of tdh2 was detected and its transcribed activity was inhibited by CalR. Moreover, the KP test results showed that the hemolytic activity of V. parahaemolyticus is also under negative control of CalR. The data demonstrated that CalR is a repressor of the tdh2 transcription and thereby inhibits the hemolytic activity of V. parahaemolyticus. Copyright © 2017. Published by Elsevier B.V.

Allicin from garlic neutralizes the hemolytic activity of intra- and extra-cellular pneumolysin O in vitro.

PubMed

Arzanlou, M; Bohlooli, S; Jannati, E; Mirzanejad-Asl, H

2011-03-15

Pneumolysin (PLY) is a key virulence factor contributes to the pathogenesis of Streptococcus pneumoniae. In this study we investigated the effect of allicin and aqueous garlic extracts on hemolytic activity of PLY both in prelysed and intact cells. Additionally the antimicrobial activity of allicin was tested against the bacteria. All tested materials potently inhibited the PLY hemolytic activity. Allicin neutralizes PLY in a concentration- and time-dependent manner. Twenty five minute incubation of PLY (2 HU/mL) with 0.61 μM/mL concentration of allicin, totally inhibited hemolytic activity of PLY (IC50 = 0.28 μM/mL). The inhibitory activity of old extract of garlic was similar to pure allicin (IC50 = 50.46 μL/mL; 0.31 μM/mL; P < 0.05). In contrast fresh extract of garlic inhibits the PLY hemolytic activity at lower concentrations (IC50 = 13.96 μL/mL; 0.08 μM/mL allicin). Exposure of intact cells to allicin (1.8 μM) completely inhibited hemolytic activity of PLY inside bacterial cells. The inhibitory effect of the allicin was restored by addition of reducing agent DTT at 5 mM, proposing that allicin likely inhibits the PLY by binding to cysteinyl residue in the binding site. The MIC value of allicin was determined to be 512 μg/mL (3.15 μM/mL). These results indicate that PLY is a novel target for allicin and may provide a new line of investigation on pneumococcal diseases in the future. Copyright © 2010 Elsevier Ltd. All rights reserved.

Nanocarriers from GRAS Zein Proteins to Encapsulate Hydrophobic Actives.

PubMed

Weissmueller, Nikolas T; Lu, Hoang D; Hurley, Amanda; Prud'homme, Robert K

2016-11-14

One factor limiting the expansion of nanomedicines has been the high cost of the materials and processes required for their production. We present a continuous, scalable, low cost nanoencapsulation process, Flash Nanoprecipitation (FNP) that enables the production of nanocarriers (NCs) with a narrow size distribution using zein corn proteins. Zein is a low cost, GRAS protein (having the FDA status of "Generally Regarded as Safe") currently used in food applications, which acts as an effective encapsulant for hydrophobic compounds using FNP. The four-stream FNP configuration allows the encapsulation of very hydrophobic compounds in a way that is not possible with previous precipitation processes. We present the encapsulation of several model active compounds with as high as 45 wt % drug loading with respect to zein concentration into ∼100 nm nanocarriers. Three examples are presented: (1) the pro-drug antioxidant, vitamin E-acetate, (2) an anticholera quorum-sensing modulator CAI-1 ((S)-3-hydroxytridecan-4-one; CAI-1 that reduces Vibrio cholerae virulence by modulating cellular communication), and (3) hydrophobic fluorescent dyes with a range of hydrophobicities. The specific interaction between zein and the milk protein, sodium caseinate, provides stabilization of the NCs in PBS, LB medium, and in pH 2 solutions. The stability and size changes in the three media provide information on the mechanism of assembly of the zein/active/casein NC.

[Dynamics of complement hemolytic activity in experimental Ebola infection].

PubMed

Zabavichene, N M; Chepurnov, A A

2004-01-01

The dynamic hemolytic activity of complements (HAC) was investigated in blood of guinea pigs in lethal and non-lethal Ebola infection. The increasing HAC dynamic activity in the animal blood was found to correlate with the infection lethal course. HAC as observed in animals with lethal infection was sweepingly increasing after they, were infected with Ebola virus, and yet after 15 hours from the infection time the complement activity parameters topped 2-fold the basic values in 100% of guinea pigs. They began to be dropping by the end of day 1, their decrease reached, when the incubation time was over (days 3-4 after infection) the basic value, after which they continued to go down to the zero value in 2-3 days before the lethal outcome. The described phenomenon, like the phenomenon of accelerated death, was even more pronounced, when the animals were infected after a single immunization by activated Ebola virus. In case, guinea pigs were infected by a non-lethal Ebola virus strain, the compliment synthesis was observed to be activated only at the end of the incubation period; the process was accompanied with a gradual raise and with a plateau-type or wave-type increase of the complement during the treatment time--it was equally accompanied with normalizing activity parameters during recovery. The detected specificity could be important in prognosticating a disease outcome. A reliable correlation was demonstrated between the complement hemolytic activity and the level of circulating immune complexes in blood of experimental animals, which can be traced both in lethal and non-lethal infection.

Decreased circulation time offsets increased efficacy of PEGylated nanocarriers targeting folate receptors of glioma

NASA Astrophysics Data System (ADS)

McNeeley, Kathleen M.; Annapragada, Ananth; Bellamkonda, Ravi V.

2007-09-01

Liposomal and other nanocarrier based drug delivery vehicles can localize to tumours through passive and/or active targeting. Passively targeted liposomal nanocarriers accumulate in tumours via 'leaky' vasculature through the enhanced permeability and retention (EPR) effect. Passive accumulation depends upon the circulation time and the degree of tumour vessel 'leakiness'. After extravasation, actively targeted liposomal nanocarriers efficiently deliver their payload by receptor-mediated uptake. However, incorporation of targeting moieties can compromise circulation time in the blood due to recognition and clearance by the reticuloendothelial system, decreasing passive accumulation. Here, we compare the efficacy of passively targeted doxorubicin-loaded PEGylated liposomal nanocarriers to that of actively targeted liposomal nanocarriers in a rat 9L brain tumour model. Although folate receptor (FR)-targeted liposomal nanocarriers had significantly reduced blood circulation time compared to PEGylated liposomal nanocarriers; intratumoural drug concentrations both at 20 and 50 h after administration were equal for both treatments. Both treatments significantly increased tumour inoculated animal survival by 60-80% compared to non-treated controls, but no difference in survival was observed between FR-targeted and passively targeted nanocarriers. Therefore, alternate approaches allowing for active targeting without compromising circulation time may be important for fully realizing the benefits of receptor-mediated active targeting of gliomas.

Characteristics of hemolytic activity induced by the aqueous extract of the Mexican fire coral Millepora complanata.

PubMed

García-Arredondo, Alejandro; Murillo-Esquivel, Luis J; Rojas, Alejandra; Sanchez-Rodriguez, Judith

2014-01-01

Millepora complanata is a plate-like fire coral common throughout the Caribbean. Contact with this species usually provokes burning pain, erythema and urticariform lesions. Our previous study suggested that the aqueous extract of M. complanata contains non-protein hemolysins that are soluble in water and ethanol. In general, the local damage induced by cnidarian venoms has been associated with hemolysins. The characterization of the effects of these components is important for the understanding of the defense mechanisms of fire corals. In addition, this information could lead to better care for victims of envenomation accidents. An ethanolic extract from the lyophilized aqueous extract was prepared and its hemolytic activity was compared with the hemolysis induced by the denatured aqueous extract. Based on the finding that ethanol failed to induce nematocyst discharge, ethanolic extracts were prepared from artificially bleached and normal M. complanata fragments and their hemolytic activity was tested in order to obtain information about the source of the heat-stable hemolysins. Rodent erythrocytes were more susceptible to the aqueous extract than chicken and human erythrocytes. Hemolytic activity started at ten minutes of incubation and was relatively stable within the range of 28-50°C. When the aqueous extract was preincubated at temperatures over 60°C, hemolytic activity was significantly reduced. The denatured extract induced a slow hemolytic activity (HU50 = 1,050.00 ± 45.85 μg/mL), detectable four hours after incubation, which was similar to that induced by the ethanolic extract prepared from the aqueous extract (HU50 = 1,167.00 ± 54.95 μg/mL). No significant differences were observed between hemolysis induced by ethanolic extracts from bleached and normal fragments, although both activities were more potent than hemolysis induced by the denatured extract. The results showed that the aqueous extract of M. complanata possesses one or

Stimuli-responsive polymeric nanocarriers for the controlled transport of active compounds: concepts and applications.

PubMed

Fleige, Emanuel; Quadir, Mohiuddin A; Haag, Rainer

2012-06-15

The use of polymeric nanocarriers to transport active compounds like small-molecular drugs, peptides, or genes found an increased attention throughout the different fields of natural sciences. Not only that these nanocarriers enhance the properties of already existing drugs in terms of solubility, bioavailability, and prolonged circulation times, furthermore they can be tailor-made in such a manner that they selectively release their cargo at the desired site of action. For the triggered release, these so-called smart drug delivery systems are designed to react on certain stimuli like pH, temperature, redox potential, enzymes, light, and ultrasound. Some of these stimuli are naturally occurring in vivo, for example the difference in pH in different cellular compartments while others are caused by the disease, which is to be treated, like differences in pH and temperature in some tumor tissues. Other external applied stimuli, like light and ultrasound, allow the temporal and spatial control of the release, since they are not triggered by any biological event. This review gives a brief overview about some types of stimuli-responsive nanocarriers with the main focus on organic polymer-based systems. Furthermore, the different stimuli and the design of corresponding responsive nanocarriers will be discussed with the help of selected examples from the literature. Copyright © 2012 Elsevier B.V. All rights reserved.

Current Progress of Virus-mimicking Nanocarriers for Drug Delivery

PubMed Central

Somiya, Masaharu; Liu, Qiushi; Kuroda, Shun'ichi

2017-01-01

Nanomedicines often involve the use of nanocarriers as a delivery system for drugs or genes for maximizing the therapeutic effect and/or minimizing the adverse effect. From drug administration to therapeutic activity, nanocarriers must evade the host's immune system, specifically and efficiently target and enter the cell, and release their payload into the cell cytoplasm by endosomal escape. These processes constitute the early infection stage of viruses. Viruses are a powerful natural nanomaterial for the efficient delivery of genetic information by sophisticated mechanisms. Over the past two decades, many virus-inspired nanocarriers have been generated to permit successful drug and gene delivery. In this review, we summarize the early infection machineries of viruses, of which the part has so far been utilized for delivery systems. Furthermore, we describe basics and applications of the bio-nanocapsule, which is a hepatitis B virus-mimicking nanoparticle harboring nearly all activities involved in the early infection machineries (i.e., stealth activity, targeting activity, cell entry activity, endosomal escaping activity). PMID:29188175

Pneumolysin with low hemolytic activity confers an early growth advantage to Streptococcus pneumoniae in the blood.

PubMed

Harvey, Richard M; Ogunniyi, Abiodun D; Chen, Austen Y; Paton, James C

2011-10-01

Streptococcus pneumoniae is a leading cause of human diseases such as pneumonia, bacteremia, meningitis, and otitis media. Pneumolysin (Ply) is an important virulence factor of S. pneumoniae and a promising future vaccine target. However, the expansion of clones carrying ply alleles with reduced hemolytic activity has been observed in serotypes associated with outbreaks of invasive disease and includes an allele identified in a highly virulent serotype 1 isolate (ply4496). The virulence of Ply-deficient and ply allelic-replacement derivatives of S. pneumoniae D39 was compared with that of wild-type D39. In addition, the protective immunogenicity of Ply against pneumococci with low versus high hemolytic activity was also investigated. Replacement of D39 ply with ply4496 resulted in a small but statistically significant reduction of virulence. However, both native Ply- and Ply4496-expressing strains were significantly more virulent than a Ply-deficient mutant. While the numbers of both Ply- and Ply4496-expressing isolate cells were higher in the blood than the numbers of Ply-deficient mutant cells, the growth of the Ply4496-expressing strain was superior to that of the wild type in the first 15 h postchallenge. Ply immunization provided protection regardless of the hemolytic activity of the challenge strain. In summary, we show that low-hemolytic-activity Ply alleles contribute to systemic virulence and may provide a survival advantage in the blood. Moreover, pneumococci expressing such alleles remain vulnerable to Ply-based vaccines.

Hemolytic crisis

MedlinePlus

Hemolytic crisis occurs when large numbers of red blood cells are destroyed over a short time. The loss of ... During a hemolytic crisis, the body cannot make enough red blood cells to replace those that are destroyed. This causes acute and often ...

Novel bio-active lipid nanocarriers for the stabilization and sustained release of sitosterol

NASA Astrophysics Data System (ADS)

Lacatusu, I.; Badea, N.; Stan, R.; Meghea, A.

2012-11-01

In this work, new stable and efficiently bio-active lipid nanocarriers (NLCs) with antioxidant properties have been developed for the transport of active ingredients in food. The novel NLCs loaded with β-sitosterol/β-sitosterol and green tea extract (GTE) and prepared by a combination of natural oils (grape seed oil, fish oil and squalene) and biological lipids with food grade surfactants, were physico-chemically examined by DLS, TEM, electrokinetic potential, DSC and HPLC and found to have main diameters less than 200 nm, a spherical morphology, excellent physical stability, an imperfect crystalline lattice and high entrapment efficiency. The novel loaded-NLCs have demonstrated the potential to develop a high blocking action of chain reactions, trapping up to 92% of the free-oxygen radicals, as compared to the native β-sitosterol (AA%=36.5). Another advantage of this study is associated with the quality of bio-active NLCs based on grape seed oil and squalene to manifest a better sitosterol—sustained release behaviour as compared to their related nanoemulsions. By coupling both in vitro results, i.e. the enhanced antioxidant activity and superior release properties, this study emphasizes the sustainability of novel bio-active nanocarriers to gain specific bio-food features for development of functional foods with a high applicability spectrum.

Food Protein Based Core-Shell Nanocarriers for Oral Drug Delivery: Effect of Shell Composition on in Vitro and in Vivo Functional Performance of Zein Nanocarriers.

PubMed

Alqahtani, Mohammed S; Islam, M Saiful; Podaralla, Satheesh; Kaushik, Radhey S; Reineke, Joshua; Woyengo, Tofuko; Perumal, Omathanu

2017-03-06

The study was aimed at systematically investigating the influence of shell composition on the particle size, stability, release, cell uptake, permeability, and in vivo gastrointestinal distribution of food protein based nanocarriers for oral delivery applications. Three different core-shell nanocarriers were prepared using food-grade biopolymers including zein-casein (ZC) nanoparticles, zein-lactoferrin (ZLF), nanoparticles and zein-PEG (ZPEG) micelles. Nile red was used as a model hydrophobic dye for in vitro studies. The nanocarriers had negative, positive, and neutral charge, respectively. All three nanocarriers had a particle size of less than 200 nm and a low polydispersity index. The nanoparticles were stable at gastrointestinal pH (2-9) and ionic strength (10-200 mM). The nanocarriers sustained the release of Nile red in simulated gastric and intestinal fluids. ZC nanoparticles showed the slowest release followed by ZLF nanoparticles and ZPEG micelles. The nanocarriers were taken up by endocytosis in Caco-2 cells. ZPEG micelles showed the highest cell uptake and transepithelial permeability followed by ZLF and ZC nanoparticles. ZPEG micelles also showed P-gp inhibitory activity. All three nanocarriers showed bioadhesive properties. Cy 5.5, a near IR dye, was used to study the in vivo biodistribution of the nanocarriers. The nanocarriers showed longer retention in the rat gastrointestinal tract compared to the free dye. Among the three formulations, ZC nanoparticles was retained the longest in the rat gastrointestinal tract (≥24 h). Overall, the outcomes from this study demonstrate the structure-function relationship of core-shell protein nanocarriers. The findings from this study can be used to develop food protein based oral drug delivery systems with specific functional attributes.

Investigation into the hemolytic activity of tentacle venom from jellyfish Cyanea nozakii Kishinouye

NASA Astrophysics Data System (ADS)

Li, Cuiping; Yu, Huahua; Li, Rongfeng; Xing, Ronge; Liu, Song; Li, Pengcheng

2016-03-01

Cyanea nozakii Kishinouy e ( C. nozakii), a giant cnidarian of the class Scyphomedusae, order Semaeostomeae and family Cyaneidae, is widely distributed in the East China Sea, the Yellow Sea and the Bohai Sea, and is abundant from late summer to early autumn. Venom produced by C. nozakii during mass agglomerations can contaminate seawater resulting in death of the halobios and seriously damage commercial fisheries. Swimmers and fishermen commonly suff er painful stings from this jellyfish, resulting in local edema, tingling, breathing difficulties, depressed blood pressure and even death. Such effects arise from the complex mixture of biologically active molecules that make up jellyfish venom. In the present study, the hemolytic activity of venom from tentacles of C. nozakii and factors aff ecting its activity were assayed. The HU50 ( defined as the amount of protein required to lyse 50 % of erythrocytes) of the venom against dove and chicken erythrocytes was 34 and 59 μg/mL, respectively. Carboxylmethyl chitosan and glycerol could increase hemolytic activity at concentrations greater than 0.06% and 0.2 mol/L, respectively.

Pneumolysin with Low Hemolytic Activity Confers an Early Growth Advantage to Streptococcus pneumoniae in the Blood ▿

PubMed Central

Harvey, Richard M.; Ogunniyi, Abiodun D.; Chen, Austen Y.; Paton, James C.

2011-01-01

Streptococcus pneumoniae is a leading cause of human diseases such as pneumonia, bacteremia, meningitis, and otitis media. Pneumolysin (Ply) is an important virulence factor of S. pneumoniae and a promising future vaccine target. However, the expansion of clones carrying ply alleles with reduced hemolytic activity has been observed in serotypes associated with outbreaks of invasive disease and includes an allele identified in a highly virulent serotype 1 isolate (ply4496). The virulence of Ply-deficient and ply allelic-replacement derivatives of S. pneumoniae D39 was compared with that of wild-type D39. In addition, the protective immunogenicity of Ply against pneumococci with low versus high hemolytic activity was also investigated. Replacement of D39 ply with ply4496 resulted in a small but statistically significant reduction of virulence. However, both native Ply- and Ply4496-expressing strains were significantly more virulent than a Ply-deficient mutant. While the numbers of both Ply- and Ply4496-expressing isolate cells were higher in the blood than the numbers of Ply-deficient mutant cells, the growth of the Ply4496-expressing strain was superior to that of the wild type in the first 15 h postchallenge. Ply immunization provided protection regardless of the hemolytic activity of the challenge strain. In summary, we show that low-hemolytic-activity Ply alleles contribute to systemic virulence and may provide a survival advantage in the blood. Moreover, pneumococci expressing such alleles remain vulnerable to Ply-based vaccines. PMID:21788389

Characterization of Antibacterial and Hemolytic Activity of Synthetic Pandinin 2 Variants and Their Inhibition against Mycobacterium tuberculosis

PubMed Central

Rodríguez, Alexis; Villegas, Elba; Montoya-Rosales, Alejandra; Rivas-Santiago, Bruno; Corzo, Gerardo

2014-01-01

The contention and treatment of Mycobacterium tuberculosis and other bacteria that cause infectious diseases require the use of new type of antibiotics. Pandinin 2 (Pin2) is a scorpion venom antimicrobial peptide highly hemolytic that has a central proline residue. This residue forms a structural “kink” linked to its pore-forming activity towards human erythrocytes. In this work, the residue Pro14 of Pin2 was both substituted and flanked using glycine residues (P14G and P14GPG) based on the low hemolytic activities of antimicrobial peptides with structural motifs Gly and GlyProGly such as magainin 2 and ponericin G1, respectively. The two Pin2 variants showed antimicrobial activity against E. coli, S. aureus, and M. tuberculosis. However, Pin2 [GPG] was less hemolytic (30%) than that of Pin2 [G] variant. In addition, based on the primary structure of Pin2 [G] and Pin2 [GPG], two short peptide variants were designed and chemically synthesized keeping attention to their physicochemical properties such as hydrophobicity and propensity to adopt alpha-helical conformations. The aim to design these two short antimicrobial peptides was to avoid the drawback cost associated to the synthesis of peptides with large sequences. The short Pin2 variants named Pin2 [14] and Pin2 [17] showed antibiotic activity against E. coli and M. tuberculosis. Besides, Pin2 [14] presented only 25% of hemolysis toward human erythrocytes at concentrations as high as 100 µM, while the peptide Pin2 [17] did not show any hemolytic effect at the same concentration. Furthermore, these short antimicrobial peptides had better activity at molar concentrations against multidrug resistance M. tuberculosis than that of the conventional antibiotics ethambutol, isoniazid and rifampicin. Therefore, Pin2 [14] and Pin2 [17] have the potential to be used as an alternative antibiotics and anti-tuberculosis agents with reduced hemolytic effects. PMID:25019413

Effects of block copolymer properties on nanocarrier protection from in vivo clearance

PubMed Central

D’Addio, Suzanne M.; Saad, Walid; Ansell, Steven M.; Squiers, John J.; Adamson, Douglas; Herrera-Alonso, Margarita; Wohl, Adam R.; Hoye, Thomas R.; Macosko, Christopher W.; Mayer, Lawrence D.; Vauthier, Christine; Prud’homme, Robert K.

2012-01-01

Drug nanocarrier clearance by the immune system must be minimized to achieve targeted delivery to pathological tissues. There is considerable interest in finding in vitro tests that can predict in vivo clearance outcomes. In this work, we produce nanocarriers with dense PEG layers resulting from block copolymer-directed assembly during rapid precipitation. Nanocarriers are formed using block copolymers with hydrophobic blocks of polystyrene (PS), poly-ε-caprolactone (PCL), poly-D,L-lactide (PLA), or poly-lactide-co-glycolide (PLGA), and hydrophilic blocks of polyethylene glycol (PEG) with molecular weights from 1.5 kg/mol to 9 kg/mol. Nanocarriers with paclitaxel prodrugs are evaluated in vivo in Foxn1nu mice to determine relative rates of clearance. The amount of nanocarrier in circulation after 4 h varies from 10% to 85% of initial dose, depending on the block copolymer. In vitro complement activation assays are conducted in an effort to correlate the protection of the nanocarrier surface from complement binding and activation and in vivo circulation. Guidelines for optimizing block copolymer structure to maximize circulation of nanocarriers formed by rapid precipitation and directed assembly are proposed, relating to the relative size of the hydrophilic and hydrophobic block, the hydrophobicity of the anchoring block, the absolute size of the PEG block, and polymer crystallinity. The in vitro results distinguish between the poorly circulating PEG5k-PCL9k and the better circulating nanocarriers, but could not rank the better circulating nanocarriers in order of circulation time. Analysis of PEG surface packing on monodisperse 200 nm latex spheres indicates that the sizes of the hydrophobic PCL, PS, and PLA blocks are correlated with the PEG blob size, and possibly the clearance from circulation. Suggestions for next step in vitro measurements are made. PMID:22732478

Sugar-Grafted Cyclodextrin Nanocarrier as a "Trojan Horse" for Potentiating Antibiotic Activity.

PubMed

Li, Min; Neoh, Koon Gee; Xu, Liqun; Yuan, Liang; Leong, David Tai; Kang, En-Tang; Chua, Kim Lee; Hsu, Li Yang

2016-05-01

The use of "Trojan Horse" nanocarriers for antibiotics to enhance the activity of antibiotics against susceptible and resistant bacteria is investigated. Antibiotic carriers (CD-MAN and CD-GLU) are prepared from β-cyclodextrin grafted with sugar molecules (D-mannose and D-glucose, respectively) via azide-alkyne click reaction. The sugar molecules serve as a chemoattractant enticing the bacteria to take in higher amounts of the antibiotic, resulting in rapid killing of the bacteria. Three types of hydrophobic antibiotics, erythromycin, rifampicin and ciprofloxacin, are used as model drugs and loaded into the carriers. The minimum inhibitory concentration of the antibiotics in the CD-MAN-antibiotic and CD-GLU-antibiotic complexes for Gram-negative Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii strains, and a number of Gram-positive Staphylococcus aureus strains, including the methicillin-resistant strains (MRSA), are reduced by a factor ranging from 3 to >100. The CD-MAN-antibiotic complex is also able to prolong the stability of the loaded antibiotic and inhibit development of intrinsic antibiotic resistance in the bacteria. These non-cytotoxic sugar-modfied nanocarriers can potentiate the activity of existing antibiotics, especially against multidrug-resistant bacteria, which is highly advantageous in view of the paucity of new antibiotics in the pipeline.

Stimulus-responsive zinc oxide-functionalized macromolecular humic acid nanocarrier for enhancement of antibacterial activity of ciprofloxacin hydrochloride.

PubMed

Murugesan, Gowri; Latha, Nachimuthu; Suganya, Kannan; Murugan, Marudhamuthu; Munusamy, Murugan A; Rajan, Mariappan

2018-07-15

Macromolecular of naturally occurring humic acid (HA) have garnered interest in the chemical, biological and medicine industry owing to their unique behavior, i.e., strong adsorptive and non-toxic nature. Here, we investigated the functionalization of organic (HA) with inorganic (ZnO) hybrid nanoparticles for topical and site-targeted delivery of ciprofloxacin by simple emulsification techniques. Ciprofloxacin (CIPRO)-encapsulated hybrid nanocarrier constitute an attractive novel drug delivery vehicle for sustained release of antibiotics to bacterial infection sites in an extended and controlled manner. The analytical characteristics of the designed system were thoroughly investigated by FTIR, XRD, SEM/EDAX, and TEM. The drug release of ciprofloxacin over 24h was 87.5%, 98.03%, 97.44%, and 97.24% for pH2.5, 5.5, 6.8, and 8.0, respectively. The antibacterial activities results confirmed that the CIPRO-encapsulated hybrid nanocarrier showed excellent growth inhibition against microorganisms. This hybrid nanocarrier loaded with antibiotics represents a promising approach for targeted and controlled drug delivery to infected sites. Copyright © 2018 Elsevier B.V. All rights reserved.

Recent Advances in Endogenous and Exogenous Stimuli-Responsive Nanocarriers for Drug Delivery and Therapeutics.

PubMed

Hatakeyama, Hiroto

2017-01-01

Significant progress has been achieved in the development of stimuli-responsive nanocarriers for drug delivery, diagnosis, and therapy. Various types of triggers are utilized in the development of nanocarrier delivery. Endogenous factors such as changes in pH, redox, gradient, and enzyme concentration which are linked to disease progression have been utilized for controlling biodistribution and releasing drugs from nanocarriers, as well as increasing subsequent pharmacological activity at the disease site. Nanocarriers which respond to artificially-induced exogenous factors (such as temperature, light, magnetic field, and ultrasound) have also been developed. This review aims to discuss recent advances in the design of stimuli-responsive nanocarriers which appear to have a promising future in medicine.

A Web Server and Mobile App for Computing Hemolytic Potency of Peptides

NASA Astrophysics Data System (ADS)

Chaudhary, Kumardeep; Kumar, Ritesh; Singh, Sandeep; Tuknait, Abhishek; Gautam, Ankur; Mathur, Deepika; Anand, Priya; Varshney, Grish C.; Raghava, Gajendra P. S.

2016-03-01

Numerous therapeutic peptides do not enter the clinical trials just because of their high hemolytic activity. Recently, we developed a database, Hemolytik, for maintaining experimentally validated hemolytic and non-hemolytic peptides. The present study describes a web server and mobile app developed for predicting, and screening of peptides having hemolytic potency. Firstly, we generated a dataset HemoPI-1 that contains 552 hemolytic peptides extracted from Hemolytik database and 552 random non-hemolytic peptides (from Swiss-Prot). The sequence analysis of these peptides revealed that certain residues (e.g., L, K, F, W) and motifs (e.g., “FKK”, “LKL”, “KKLL”, “KWK”, “VLK”, “CYCR”, “CRR”, “RFC”, “RRR”, “LKKL”) are more abundant in hemolytic peptides. Therefore, we developed models for discriminating hemolytic and non-hemolytic peptides using various machine learning techniques and achieved more than 95% accuracy. We also developed models for discriminating peptides having high and low hemolytic potential on different datasets called HemoPI-2 and HemoPI-3. In order to serve the scientific community, we developed a web server, mobile app and JAVA-based standalone software (http://crdd.osdd.net/raghava/hemopi/).

A Web Server and Mobile App for Computing Hemolytic Potency of Peptides.

PubMed

Chaudhary, Kumardeep; Kumar, Ritesh; Singh, Sandeep; Tuknait, Abhishek; Gautam, Ankur; Mathur, Deepika; Anand, Priya; Varshney, Grish C; Raghava, Gajendra P S

2016-03-08

Numerous therapeutic peptides do not enter the clinical trials just because of their high hemolytic activity. Recently, we developed a database, Hemolytik, for maintaining experimentally validated hemolytic and non-hemolytic peptides. The present study describes a web server and mobile app developed for predicting, and screening of peptides having hemolytic potency. Firstly, we generated a dataset HemoPI-1 that contains 552 hemolytic peptides extracted from Hemolytik database and 552 random non-hemolytic peptides (from Swiss-Prot). The sequence analysis of these peptides revealed that certain residues (e.g., L, K, F, W) and motifs (e.g., "FKK", "LKL", "KKLL", "KWK", "VLK", "CYCR", "CRR", "RFC", "RRR", "LKKL") are more abundant in hemolytic peptides. Therefore, we developed models for discriminating hemolytic and non-hemolytic peptides using various machine learning techniques and achieved more than 95% accuracy. We also developed models for discriminating peptides having high and low hemolytic potential on different datasets called HemoPI-2 and HemoPI-3. In order to serve the scientific community, we developed a web server, mobile app and JAVA-based standalone software (http://crdd.osdd.net/raghava/hemopi/).

Resveratrol-Loaded Lipid Nanocarriers: Correlation between In Vitro Occlusion Factor and In Vivo Skin Hydrating Effect

PubMed Central

Parenti, Carmela; Turnaturi, Rita

2017-01-01

Lipid nanocarriers show occlusive properties that may be related to their ability to improve skin hydration. The aim of this work was to evaluate the relationship between in vitro occlusion factor and in vivo skin hydration for three types of lipid nanocarriers: nanoemulsions (NEs), solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs). These lipid nanocarriers were loaded with trans-resveratrol (RSV) and incorporated in gel vehicles. In vitro occlusion factor was in the order SLNs > NLCs > NEs. Gels containing unloaded or RSV loaded lipid nanocarriers were applied on the back of a hand of 12 healthy volunteers twice a day for one week, recording skin hydration changes using the instrument Soft Plus. An increase of skin hydration was observed for all lipid nanocarriers (SLNs > NLCs > NEs). RSV loading into these nanocarriers did not affect in vitro and in vivo lipid nanocarriers effects. A linear relationship (r2 = 0.969) was observed between occlusion factor and in vivo increase of skin hydration. Therefore, the results of this study showed the feasibility of using the occlusion factor to predict in vivo skin hydration resulting from topical application of different lipid nanocarriers loading an active ingredient with no inherent hydrating activity. PMID:29232856

Antibacterial activity of antipsychotic agents, their association with lipid nanocapsules and its impact on the properties of the nanocarriers and on antibacterial activity.

PubMed

Nehme, Hassan; Saulnier, Patrick; Ramadan, Alyaa A; Cassisa, Viviane; Guillet, Catherine; Eveillard, Matthieu; Umerska, Anita

2018-01-01

Bacterial antibiotic resistance is an emerging public health problem worldwide; therefore, new therapeutic strategies are needed. Many studies have described antipsychotic compounds that present antibacterial activity. Hence, the aims of this study were to evaluate the in vitro antibacterial activity of antipsychotics belonging to different chemical families, to assess the influence of their association with lipid nanocapsules (LNCs) on their antimicrobial activity as well as drug release and to study the uptake of LNCs by bacterial cells. Antibacterial activity was evaluated against Gram-positive Staphylococcus aureus and Gram negative Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii by minimum inhibitory concentration (MIC) assay, and the capability of killing tested microorganisms was evaluated by time kill assay. LNCs were prepared by phase inversion method, and the antipsychotic agents were incorporated using pre-loading and post-loading strategies. Only phenothiazines and thioxanthenes showed antibacterial activity, which was independent of antibiotic-resistance patterns. Loading the nanocarriers with the drugs affected the properties of the former, particularly their zeta potential. The release rate depended on the drug and its concentration-a maximum of released drug of less than 40% over 24 hours was observed for promazine. The influence of the drug associations on the antibacterial properties was concentration-dependent since, at low concentrations (high nanocarrier/drug ratio), the activity was lost, probably due to the high affinity of the drug to nanocarriers and slow release rate, whereas at higher concentrations, the activity was well maintained for the majority of the drugs. Chlorpromazine and thioridazine increased the uptake of the LNCs by bacteria compared with blank LNCs, even below the minimum inhibitory concentration.

Hemolytic uremic syndrome complicating Mycoplasma pneumoniae infection.

PubMed

Godron, Astrid; Pereyre, Sabine; Monet, Catherine; Llanas, Brigitte; Harambat, Jérôme

2013-10-01

Mycoplasma pneumoniae can cause various extrapulmonary manifestations but, to our knowledge, no case of Mycoplasma pneumoniae associated with hemolytic uremic syndrome (HUS) has been reported. We describe a 1-year-old boy with M. pneumoniae respiratory tract infection and associated microangiopathic hemolytic anemia, slightly decreased platelet count and mild renal impairment, suggesting a diagnosis of HUS. Assuming M. pneumoniae infection was the cause of HUS in this case, the different possible mechanisms, including an atypical HUS due to preexisting complement dysregulation, an alternative complement pathway activation induced by M. pneumoniae infection at the acute phase, an autoimmune disorder, and a direct role of the bacteria in inducing endothelial injury, are discussed. The signs of HUS resolved with treatment of the M. pneumoniae infection. Hemolytic uremic syndrome may be an unusual complication of M. pneumoniae infection.

Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom.

PubMed

Kang, Changkeun; Munawir, Al; Cha, Mijin; Sohn, Eun-Tae; Lee, Hyunkyoung; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Kim, Euikyung

2009-07-01

The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC(50)=2 microg/mL vs. 12 microg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (or=60 degrees C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pHactivity was not significantly affected even at the highest pH environment tested (pHhemolytic activity of the venom was examined using the erythrocytes of cat, dog, human, rabbit and rat. Venom concentration-dependent hemolysis could be observed from 10 microg/mL of protein equivalents or higher with variable potencies in different species, among which dog erythrocyte was the most susceptible to the venom (EC(50)=151 microg/mL). SDS-PAGE analysis of N. nomurai venom showed the molecules of 20-40 kDa and 10-15 kDa appeared to be the major protein components of the venom.

Red wines and flavonoids diminish Staphylococcus aureus virulence with anti-biofilm and anti-hemolytic activities.

PubMed

Cho, Hyun Seob; Lee, Jin-Hyung; Cho, Moo Hwan; Lee, Jintae

2015-01-01

The emergence of antibiotic resistant Staphylococcus aureus presents a worldwide problem that requires non-antibiotic strategies. This study investigated the anti-biofilm and anti-hemolytic activities of four red wines and two white wines against three S. aureus strains. All red wines at 0.5-2% significantly inhibited S. aureus biofilm formation and hemolysis by S. aureus, whereas the two white wines had no effect. Furthermore, at these concentrations, red wines did not affect bacterial growth. Analyses of hemolysis and active component identification in red wines revealed that the anti-biofilm compounds and anti-hemolytic compounds largely responsible were tannic acid, trans-resveratrol, and several flavonoids. In addition, red wines attenuated S. aureus virulence in vivo in the nematode Caenorhabditis elegans, which is killed by S. aureus. These findings show that red wines and their compounds warrant further attention in antivirulence strategies against persistent S. aureus infection.

Vegetable Peel Waste for the Production of ZnO Nanoparticles and its Toxicological Efficiency, Antifungal, Hemolytic, and Antibacterial Activities

NASA Astrophysics Data System (ADS)

Surendra, T. V.; Roopan, Selvaraj Mohana; Al-Dhabi, Naif Abdullah; Arasu, Mariadhas Valan; Sarkar, Gargi; Suthindhiran, K.

2016-12-01

Zinc oxide (ZnO) nanoparticles (NPs) are important materials when making different products like sun screens, textiles, and paints. In the current study, the photocatalytic effect of prepared ZnO NPs from Moringa oleifera ( M. oleifera) was evaluated on degradation of crystal violet (CV) dye, which is largely released from textile industries and is harmful to the environment. Preliminarily, ZnO NP formation was confirmed using a double beam ultraviolet visible (UV-Vis) spectrophotometer; further, the NP size was estimated using XRD analysis and the functional group analysis was determined using Fourier transform infrared (FT-IR) spectroscopy. The morphology of the synthesized NPs was found to be a hexagonal shape using SEM and TEM analysis and elemental screening was analyzed using EDX. ZnO NPs were shown sized 40-45 nm and spherical in shape. The degradation percentage of ZnO NPs was calculated as 94% at 70 min and the rate of the reaction -k = 0.0282. The synthesized ZnO NPs were determined for effectiveness on biological activities such as antifungal, hemolytic, and antibacterial activity. ZnO NPs showed good antifungal activity against Alternaria saloni and Sclerrotium rolfii strains. Further, we have determined the hemolytic and antibacterial activity of ZnO NPs and we got successive results in antibacterial and hemolytic activities.

Grafting synthetic transmembrane units to the engineered low-toxicity α-hemolysin to restore its hemolytic activity.

PubMed

Ui, Mihoko; Harima, Kousuke; Takei, Toshiaki; Tsumoto, Kouhei; Tabata, Kazuhito V; Noji, Hiroyuki; Endo, Sumire; Akiyama, Kimio; Muraoka, Takahiro; Kinbara, Kazushi

2014-12-01

The chemical modification of proteins to provide desirable functions and/or structures broadens their possibilities for use in various applications. Usually, proteins can acquire new functions and characteristics, in addition to their original ones, via the introduction of synthetic functional moieties. Here, we adopted a more radical approach to protein modification, i.e., the replacement of a functional domain of proteins with alternative chemical compounds to build "cyborg proteins." As a proof of concept model, we chose staphylococcal α-hemolysin (Hla), which is a well-studied, pore-forming toxin. The hemolytic activity of Hla mutants was dramatically decreased by truncation of the stem domain, which forms a β-barrel pore in the membrane. However, the impaired hemolytic activity was significantly restored by attaching a pyrenyl-maleimide unit to the cysteine residue that was introduced in the remaining stem domain. In contrast, negatively charged fluorescein-maleimide completely abolished the remaining activity of the mutants.

Advanced nanocarriers based on heparin and its derivatives for cancer management.

PubMed

Yang, Xiaoye; Du, Hongliang; Liu, Jiyong; Zhai, Guangxi

2015-02-09

To obtain a satisfying anticancer effect, rationally designed nanocarriers are intensively studied. In this field, heparin and its derivatives have been widely attempted recently as potential component of nanocarriers due to their unique biological and physiochemical features, especially the anticancer activity. This review focuses on state-of-the-art nanocarriers with heparin/heparin derivatives as backbone or coating material. At the beginning, the unique advantages of heparin used in cancer nanotechnology are discussed. After that, different strategies of heparin chemical modification are reviewed, laying the foundation of developing various nanocarriers. Then a systematic summary of diverse nanoparticles with heparin as component is exhibited, involving heparin-drug conjugate, polymeric nanoparticles, nanogels, polyelectrolyte complex nanoparticles, and heparin-coated organic and inorganic nanoparticles. The application of these nanoparticles in various novel cancer therapy (containing targeted therapy, magnetic therapy, photodynamic therapy, and gene therapy) will be highlighted. Finally, future challenges and opportunities of heparin-based biomaterials in cancer nanotechnology are discussed.

Hemolytic activity of Fusobacterium necrophorum culture supernatants due to presence of phospholipase A and lysophospholipase.

PubMed

Abe, P M; Kendall, C J; Stauffer, L R; Holland, J W

1979-01-01

Culture supernatants of Fusobacterium necrophorum demonstrated hemolytic activity. The hemolysin(s), which was partially purified by ammonium sulfate precipitation, was temperature-dependent and heat labile. The spectrum of hemolytic activity against various erythrocytes included rabbit, human, and dog erythrocytes. Goats, sheep, and bovine erythrocytes showed only trace hemolysis. According to results of thin-layer chromatography, the hemolysin hydrolyzed rabbit erythrocyte phosphatidyl choline, phosphatidyl ethanolamine, lysophosphatidyl choline, and bovine phosphatidyl choline. Hydrolysis of egg yolk phosphatidyl choline, bovine phosphatidyl ethanolamine, cholesterol, 1,2-dipalmitin, 1,3-dipalmitin, sphingomyelin, or triolein was not detected by thin layer chromatography. A more sensitive procedure utilizing gas-liquid chromatography revealed that, of the substrates tested, the following were bein hydrolyzed: bovine and egg yolk phosphatidyl choline, lysophosphatidyl choline, alpha-palmito-beta-eleoyl-L-alpha lecithin and alpha-oleoyl-betal-palmitoyl-L-alpha lecithin. Substrates which were weakly hydrolyzed were bovine phosphatidyl ethanolamine, DL-alpha-hosphatidyl ethanolamine dipalmitoyl, 1,2-dipalmitin, 1,3-dipalmitin, and triolein.

Recent advances in hyaluronic acid-decorated nanocarriers for targeted cancer therapy

PubMed Central

Wickens, Jennifer M.; Alsaab, Hashem O.; Kesharwani, Prashant; Bhise, Ketki; Amin, Mohd Cairul Iqbal Mohd; Tekade, Rakesh Kumar; Gupta, Umesh; Iyer, Arun K.

2016-01-01

The cluster-determinant 44 (CD44) receptor has a high affinity for hyaluronic acid (HA) binding and is a desirable receptor for active targeting based on its overexpression in cancer cells compared with normal body cells. The nanocarrier affinity can be increased by conjugating drug-loaded carriers with HA, allowing enhanced cancer cell uptake via the HA-CD44 receptor-mediated endocytosis pathway. In this review, we discuss recent advances in HA-based nanocarriers and micelles for cancer therapy. In vitro and in vivo experiments have repeatedly indicated HA-based nanocarriers to be a target-specific drug and gene delivery platform with great promise for future applications in clinical cancer therapy. PMID:28017836

Recent advances in hyaluronic acid-decorated nanocarriers for targeted cancer therapy.

PubMed

Wickens, Jennifer M; Alsaab, Hashem O; Kesharwani, Prashant; Bhise, Ketki; Amin, Mohd Cairul Iqbal Mohd; Tekade, Rakesh Kumar; Gupta, Umesh; Iyer, Arun K

2017-04-01

The cluster-determinant 44 (CD44) receptor has a high affinity for hyaluronic acid (HA) binding and is a desirable receptor for active targeting based on its overexpression in cancer cells compared with normal body cells. The nanocarrier affinity can be increased by conjugating drug-loaded carriers with HA, allowing enhanced cancer cell uptake via the HA-CD44 receptor-mediated endocytosis pathway. In this review, we discuss recent advances in HA-based nanocarriers and micelles for cancer therapy. In vitro and in vivo experiments have repeatedly indicated HA-based nanocarriers to be a target-specific drug and gene delivery platform with great promise for future applications in clinical cancer therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lysosomal enzyme delivery by ICAM-1-targeted nanocarriers bypassing glycosylation- and clathrin-dependent endocytosis.

PubMed

Muro, Silvia; Schuchman, Edward H; Muzykantov, Vladimir R

2006-01-01

Enzyme replacement therapy, a state-of-the-art treatment for many lysosomal storage disorders, relies on carbohydrate-mediated binding of recombinant enzymes to receptors that mediate lysosomal delivery via clathrin-dependent endocytosis. Suboptimal glycosylation of recombinant enzymes and deficiency of clathrin-mediated endocytosis in some lysosomal enzyme-deficient cells limit delivery and efficacy of enzyme replacement therapy for lysosomal disorders. We explored a novel delivery strategy utilizing nanocarriers targeted to a glycosylation- and clathrin-independent receptor, intercellular adhesion molecule (ICAM)-1, a glycoprotein expressed on diverse cell types, up-regulated and functionally involved in inflammation, a hallmark of many lysosomal disorders. We targeted recombinant human acid sphingomyelinase (ASM), deficient in types A and B Niemann-Pick disease, to ICAM-1 by loading this enzyme to nanocarriers coated with anti-ICAM. Anti-ICAM/ASM nanocarriers, but not control ASM or ASM nanocarriers, bound to ICAM-1-positive cells (activated endothelial cells and Niemann-Pick disease patient fibroblasts) via ICAM-1, in a glycosylation-independent manner. Anti-ICAM/ASM nanocarriers entered cells via CAM-mediated endocytosis, bypassing the clathrin-dependent pathway, and trafficked to lysosomes, where delivered ASM displayed stable activity and alleviated lysosomal lipid accumulation. Therefore, lysosomal enzyme targeting using nanocarriers targeted to ICAM-1 bypasses defunct pathways and may improve the efficacy of enzyme replacement therapy for lysosomal disorders, such as Niemann-Pick disease.

Stimuli-responsive chitosan-based nanocarriers for cancer therapy

PubMed Central

Fathi, Marziyeh; Sahandi Zangabad, Parham; Majidi, Sima; Barar, Jaleh; Erfan-Niya, Hamid

2017-01-01

Introduction: Stimuli-responsive nanocarriers offer unique advantages over the traditional drug delivery systems (DDSs) in terms of targeted drug delivery and on-demand release of cargo drug molecules. Of these, chitosan (CS)-based DDSs offer several advantages such as high compatibility with biological settings. Methods: In this study, we surveyed the literature in terms of the stimuli-responsive nanocarriers and discussed the most recent advancements in terms of CS-based nanosystems and their applications in cancer therapy and diagnosis. Results: These advanced DDSs are able to release the entrapped drugs in response to a specific endogenous stimulus (e.g., pH, glutathione concentration or certain enzymes) or exogenous stimulus (e.g., temperature, light, ultrasound, and magnetic field) at the desired time and target site. Dual-responsive nanocarriers by the combination of different stimuli have also been developed as efficient and improved DDSs. Among the stimuli-responsive nanocarriers, CS-based DDSs offer several advantages, including biocompatibility and biodegradability, antibacterial activity, ease of modification and functionalization, and non-immunogenicity. They are as one of the most ideal smart multifunction DDSs. Conclusion: The CS-based stimuli-responsive multifunctional nanosystems (NSs) offer unique potential for the targeted delivery of anticancer agents and provide great potential for on-demand and controlled-release of anticancer agents in response to diverse external/internal stimuli. PMID:29435435

Stimuli-responsive chitosan-based nanocarriers for cancer therapy.

PubMed

Fathi, Marziyeh; Sahandi Zangabad, Parham; Majidi, Sima; Barar, Jaleh; Erfan-Niya, Hamid; Omidi, Yadollah

2017-01-01

Introduction: Stimuli-responsive nanocarriers offer unique advantages over the traditional drug delivery systems (DDSs) in terms of targeted drug delivery and on-demand release of cargo drug molecules. Of these, chitosan (CS)-based DDSs offer several advantages such as high compatibility with biological settings. Methods: In this study, we surveyed the literature in terms of the stimuli-responsive nanocarriers and discussed the most recent advancements in terms of CS-based nanosystems and their applications in cancer therapy and diagnosis. Results: These advanced DDSs are able to release the entrapped drugs in response to a specific endogenous stimulus (e.g., pH, glutathione concentration or certain enzymes) or exogenous stimulus (e.g., temperature, light, ultrasound, and magnetic field) at the desired time and target site. Dual-responsive nanocarriers by the combination of different stimuli have also been developed as efficient and improved DDSs. Among the stimuli-responsive nanocarriers, CS-based DDSs offer several advantages, including biocompatibility and biodegradability, antibacterial activity, ease of modification and functionalization, and non-immunogenicity. They are as one of the most ideal smart multifunction DDSs. Conclusion: The CS-based stimuli-responsive multifunctional nanosystems (NSs) offer unique potential for the targeted delivery of anticancer agents and provide great potential for on-demand and controlled-release of anticancer agents in response to diverse external/internal stimuli.

New doxorubicin nanocarriers based on cyclodextrins.

PubMed

Viale, Maurizio; Giglio, Valentina; Monticone, Massimiliano; Maric, Irena; Lentini, Giovanni; Rocco, Mattia; Vecchio, Graziella

2017-10-01

Polymeric nanoparticles and fibrin gels (FBGs) are attractive biomaterials for local delivery of a variety of biotherapeutic agents, from drugs to proteins. We combined these different drug delivery approaches by preparing nanoparticle-loaded FBGs characterized by their intrinsic features of drug delivery rate and antiproliferative/apoptotic activities. Inclusion complexes of doxorubicin (DOXO) with oligomeric β-cyclodextrins (oCyD) functionalized with different functional groups were studied. These nanocarriers were able to interact with FBGs as shown by a decreased release rate of DOXO. One of these complexes, oCyDNH 2 /DOXO, demonstrated good antiproliferative and apoptotic activity in vitro, reflecting a higher drug uptake by cells. As hypothesized, the nanocarrier/FBG complexes showed a lower drug release rate than similar FBGs loaded with the corresponding non-functionalized oCyD/DOXO. Taken together, our results provide experimental evidence that oCyDNH 2 /DOXO complexes may be useful components in enhanced FBGs and further build support for the great promise these complex molecules hold for clinical use in localized anticancer therapy of inoperable or surgically removable tumors of different histological origin.

Photochemical mechanisms of light-triggered release from nanocarriers

PubMed Central

Fomina, Nadezda; Sankaranarayanan, Jagadis; Almutairi, Adah

2012-01-01

Over the last three decades, a handful of photochemical mechanisms have been applied to a large number of nanoscale assemblies that encapsulate a payload to afford spatio-temporal and remote control over activity of the encapsulated payload. Many of these systems are designed with an eye towards biomedical applications, as spatio-temporal and remote control of bioactivity would advance research and clinical practice. This review covers five underlying photochemical mechanisms that govern the activity of the majority of photoresponsive nanocarriers: 1. photo driven isomerization and oxidation, 2. surface plasmon absorption and photothermal effects, 3. photo driven hydrophobicity changes, 4. photo driven polymer backbone fragmentation and 5. photo driven de-crosslinking. The ways in which these mechanisms have been incorporated into nanocarriers and how they affect release is detailed, as well as the advantages and disadvantages of each system. PMID:22386560

Stevia rebaudiana Bertoni effect on the hemolytic potential of Listeria monocytogenes.

PubMed

Sansano, S; Rivas, A; Pina-Pérez, M C; Martinez, A; Rodrigo, D

2017-06-05

The effect of Stevia rebaudiana Bertoni on the hemolytic potential of Listeria monocytogenes was studied by means of the assessment of the Listeriolysin O (LLO) production. The three factors under study, stevia concentration in the range [0-2.5] % (w/v), incubation temperature (10 and 37°C), and exposure time (0-65h) significantly affected (p≤0.05) the hemolytic activity of L. monocytogenes. Results showed that at the lower incubation temperature the hemolytic potential of the bacterium was significantly reduced, from 100% at 37°C to 8% at 10°C (after 65h of incubation) in unsupplemented substrate (0% stevia). Irrespective of the temperature, 10 or 37°C, supplementation of the medium with stevia at 2.5 % (w/v) reduced the bacterium's hemolytic activity by a maximum of 100%. Furthermore, the time of exposure to 2.5 % (w/v) stevia concentration was also a significant factor reducing the hemolytic capability of L. monocytogenes. The possibility of reducing the pathogenic potential of L. monocytogenes (hemolysis) by exposure to stevia should be confirmed in real food matrices, opening a research niche with a valuable future impact on food safety. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of sodium dodecyl sulfate on the conformation and hemolytic activity of St I and St II, two isotoxins purified from Stichodactyla helianthus.

PubMed

Lanio, M E; Alvarez, C; Pazos, F; Martinez, D; Martínez, Y; Casallanovo, F; Abuin, E; Schreier, S; Lissi, E

2003-01-01

The effect of sodium dodecyl sulfate (SDS) upon the conformation and hemolytic activity of St I and St II strongly depends on its concentration. At relatively low surfactant concentrations (ca. 0.5-5mM range) the surfactant leads to the formation of aggregates, as suggested by the turbidity observed even at relatively low (micromolar range) protein concentrations. In this surfactant range, the proteins show an increase in intrinsic fluorescence intensity and reduced quenching by acrylamide, with an almost total loss of its hemolytic activity. At higher surfactant concentrations the protein adducts disaggregates. This produces a decrease in fluorescence intensity, increase in quenching efficiency by acrylamide, loss of the native tertiary conformation (as reported by the near UV-CD spectra), and increase in alpha-helix content (as evidenced by the far UV-CD spectra). However, and in spite of these substantial changes, the toxins partially recover their hemolytic activity. The reasons for this recovering of the activity at high surfactant concentrations is discussed.

Poly(ethylene glycol) (PEG)-lactic acid nanocarrier-based degradable hydrogels for restoring the vaginal microenvironment

PubMed Central

Rajan, Sujata Sundara; Turovskiy, Yevgeniy; Singh, Yashveer; Chikindas, Michael L.; Sinko, Patrick J.

2014-01-01

Women with bacterial vaginosis (BV) display reduced vaginal acidity, which make them susceptible to associated infections such as HIV. In the current study, poly(ethylene glycol) (PEG) nanocarrier-based degradable hydrogels were developed for the controlled release of lactic acid in the vagina of BV-infected women. PEG-lactic acid (PEG-LA) nanocarriers were prepared by covalently attaching lactic acid to 8-arm PEG-SH via cleavable thioester bonds. PEG-LA nanocarriers with 4 copies of lactic acid per molecule provided controlled release of lactic acid with a maximum release of 23% and 47% bound lactic acid in phosphate buffered saline (PBS, pH 7.4) and acetate buffer (AB, pH 4.3), respectively. The PEG nanocarrier-based hydrogels were formed by cross-linking the PEG-LA nanocarriers with 4-arm PEG-NHS via degradable thioester bonds. The nanocarrier-based hydrogels formed within 20 min under ambient conditions and exhibited an elastic modulus that was 100-fold higher than the viscous modulus. The nanocarrier-based degradable hydrogels provided controlled release of lactic acid for several hours; however, a maximum release of only 10%–14% bound lactic acid was observed possibly due to steric hindrance of the polymer chains in the cross-linked hydrogel. In contrast, hydrogels with passively entrapped lactic acid showed burst release with complete release within 30 min. Lactic acid showed antimicrobial activity against the primary BV pathogen Gardnerella vaginalis with a minimum inhibitory concentration (MIC) of 3.6 mg/ml. In addition, the hydrogels with passively entrapped lactic acid showed retained antimicrobial activity with complete inhibition G. vaginalis growth within 48 h. The results of the current study collectively demonstrate the potential of PEG nanocarrier-based hydrogels for vaginal administration of lactic acid for preventing and treating BV. PMID:25223229

Drug-induced immune hemolytic anemia

MedlinePlus

Immune hemolytic anemia secondary to drugs; Anemia - immune hemolytic - secondary to drugs ... In some cases, a drug can cause the immune system to mistake your own red blood cells for foreign substances. The body responds by making ...

Ultrasound-Mediated Local Drug and Gene Delivery Using Nanocarriers

PubMed Central

Zhou, Qiu-Lan; Chen, Zhi-Yi; Yang, Feng

2014-01-01

With the development of nanotechnology, nanocarriers have been increasingly used for curative drug/gene delivery. Various nanocarriers are being introduced and assessed, such as polymer nanoparticles, liposomes, and micelles. As a novel theranostic system, nanocarriers hold great promise for ultrasound molecular imaging, targeted drug/gene delivery, and therapy. Nanocarriers, with the properties of smaller particle size, and long circulation time, would be advantageous in diagnostic and therapeutic applications. Nanocarriers can pass through blood capillary walls and cell membrane walls to deliver drugs. The mechanisms of interaction between ultrasound and nanocarriers are not clearly understood, which may be related to cavitation, mechanical effects, thermal effects, and so forth. These effects may induce transient membrane permeabilization (sonoporation) on a single cell level, cell death, and disruption of tissue structure, ensuring noninvasive, targeted, and efficient drug/gene delivery and therapy. The system has been used in various tissues and organs (in vitro or in vivo), including tumor tissues, kidney, cardiac, skeletal muscle, and vascular smooth muscle. In this review, we explore the research progress and application of ultrasound-mediated local drug/gene delivery with nanocarriers. PMID:25202710

[Balance between cardiovascular pharmacological and hemolytic effects of saponins of Panax notogenseng].

PubMed

Han, Shu-Xian; You, Yun

2016-03-01

PNS (total saponins of Panax notognseng, PNS) has a clear effect and wide application prospect for cardiovascular diseases. At the same time, saponins have hemolytic properties, which are related to its molecular structure type and dosage. On one hand, this article summarizes the research progress of PNS in heart cerebrovascular pharmacology pharmacological in recent five years, a number of studies both in vitro and in vivo for overall body, organs, cells and molecules, show that PNS could improve myocardial and cerebral ischemia injury, and it has effects in resisting thrombosis, inflammation, oxidation, atherosclerosis, and modulating vascular endothelial cells function and improving the cerebral ischemia injury etc. On the other hand, the hemolysis effect of PNS is closely related to its molecular structure type and administrating dosage. Different structures bring about different hemolysis activities. Structure-activity relationship suggests that the length of sugar side chains attached to C-20 and the disaccharide connection mode on C-3 may influence the hemolysis activity of PNS. Within the dose range from 2.5 to 250 mg•L⁻¹, PNS has no hemolysis activity. However, PNS exhibits hemolytic properties at high concentrations(≥500 mg•L⁻¹). Based on the hemolytic or anti-hemolysis characteristics of saponins, and dose-response relationship, the rational clinical application of PNS can be guaranteed by controlling the ratio of hemolytic monosaponins in PNS and improving the hemolytic test method. Copyright© by the Chinese Pharmaceutical Association.

Synthesis, characterization, in vitro anti-proliferative and hemolytic activity of hydroxyapatite

NASA Astrophysics Data System (ADS)

Palanivelu, R.; Ruban Kumar, A.

2014-06-01

Hydroxyapatite (Ca10(PO4)6(OH)2, HAP) nanoparticles are widely used in several biomedical applications due to its compositional similarities to bone mineral, excellent biocompatibility and bioactivity, osteoconductivity. In this present investigation, HAP nanoparticles synthesized by precipitation technique using calcium nitrate and di-ammonium phosphate. The crystalline nature and the functional group analysis are confirmed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Fourier transform Raman spectroscopy (FT-Raman) respectively. The morphological observations are ascertained from field emission electron scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). In vitro anti-proliferative and hemolytic activities are carried out on the synthesized HAP samples and the studies reveals that HAP have mild activity against erythrocytes.

Antioxidant and hemolytic activities, and effects in rat cutaneous wound healing of a novel polysaccharide from fenugreek (Trigonella foenum-graecum) seeds.

PubMed

Ktari, Naourez; Trabelsi, Imen; Bardaa, Sana; Triki, Mehdi; Bkhairia, Intidhar; Ben Slama-Ben Salem, Rabab; Nasri, Moncef; Ben Salah, Riadh

2017-02-01

The aim of this work was to evaluate the antioxidant and hemolytic activities as well as the in vivo wound healing performance of a novel polysaccharide (FWEP) extracted from fenugreek (Trigonella foenum-graecum) seeds. The antioxidant activity was evaluated in vivo and in vitro using various assays. Results showed that FWEP exhibited strong antioxidant activities but no hemolytic activity was observed towards bovine erythrocytes. The application of FWEP hydrogel on the wound site in a rat model enhanced significantly wound healing activity and accelerated the wound closure after 14days of wound induction. Histological examination also demonstrated fully re-epithelialized wound with a complete epidermal regeneration. Altogether, these evidences demonstrated that FWEP had strong wound healing potential presumably achieved through its antioxidant activities. Copyright © 2016 Elsevier B.V. All rights reserved.

Enhanced Delivery and Effects of Acid Sphingomyelinase by ICAM-1-Targeted Nanocarriers in Type B Niemann-Pick Disease Mice.

PubMed

Garnacho, Carmen; Dhami, Rajwinder; Solomon, Melani; Schuchman, Edward H; Muro, Silvia

2017-07-05

Acid sphingomyelinase deficiency in type B Niemann-Pick disease leads to lysosomal sphingomyelin storage, principally affecting lungs, liver, and spleen. Infused recombinant enzyme is beneficial, yet its delivery to the lungs is limited and requires higher dosing than liver and spleen, leading to potentially adverse reactions. Previous studies showed increased enzyme pulmonary uptake by nanocarriers targeted to ICAM-1, a protein overexpressed during inflammation. Here, using polystyrene and poly(lactic-co-glycolic acid) nanocarriers, we optimized lung delivery by varying enzyme dose and nanocarrier concentration, verified endocytosis and lysosomal trafficking in vivo, and evaluated delivered activity and effects. Raising the enzyme load of nanocarriers progressively increased absolute enzyme delivery to all lung, liver, and spleen, over the naked enzyme. Varying nanocarrier concentration inversely impacted lung versus liver and spleen uptake. Mouse intravital and postmortem examination verified endocytosis, transcytosis, and lysosomal trafficking using nanocarriers. Compared to naked enzyme, nanocarriers increased enzyme activity in organs and reduced lung sphingomyelin storage and macrophage infiltration. Although old mice with advanced disease showed reactivity (pulmonary leukocyte infiltration) to injections, including buffer without carriers, antibody, or enzyme, younger mice with mild disease did not. We conclude that anti-ICAM nanocarriers may result in effective lung enzyme therapy using low enzyme doses. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

A novel nano-carrier transdermal gel against inflammation.

PubMed

Chaudhary, Hema; Kohli, Kanchan; Kumar, Vikash

2014-04-25

The objective was to develop a stable, reproducible and patient non-infringing novel transdermal drug delivery system "nano-carrier transdermal gel" (NCTG) in combination of partial dose replacement of diclofenac diethylamine (DDEA) by curcumin (CRM). The drug content of gel was 99.30 and 97.57% for DDEA and CRM. Plasma samples were analyzed by liquid chromatography with triple-quadrupole tandem mass spectrometer (LC-MS/MS). Data were integrated with Analyst™ and analyzed by WinNonlin; stability parameters were analyzed using Tukey-Kramer multiple comparison test. Its average skin irritation scored 0.49 concluded to be non-irritant, safe for human use and in vivo studies revealed significantly greater extent of absorption and highly significant inhibition (%) of carrageenan induced paw edema. The results also demonstrated that encapsulation of drugs in nano-carrier increases its biological activity due to superior skin penetration potential. Hence, a novel once day transdermal gel of nano-carrier (nano-transfersomes; deformable vesicular) is achieved, to increase systemic availability, subsequent reduction in dose and toxicity of DDEA was developed for the treatment of inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

Dissection of the antimicrobial and hemolytic activity of Cap18: Generation of Cap18 derivatives with enhanced specificity.

PubMed

Ebbensgaard, Anna; Mordhorst, Hanne; Overgaard, Michael Toft; Aarestrup, Frank Møller; Hansen, Egon Bech

2018-01-01

Due to the rapid emergence of resistance to classical antibiotics, novel antimicrobial compounds are needed. It is desirable to selectively kill pathogenic bacteria without targeting other beneficial bacteria in order to prevent the negative clinical consequences caused by many broad-spectrum antibiotics as well as reducing the development of antibiotic resistance. Antimicrobial peptides (AMPs) represent an alternative to classical antibiotics and it has been previously demonstrated that Cap18 has high antimicrobial activity against a broad range of bacterial species. In this study we report the design of a positional scanning library consisting of 696 Cap18 derivatives and the subsequent screening for antimicrobial activity against Y. ruckeri, A. salmonicida, S. Typhimurium and L. lactis as well as for hemolytic activity measuring the hemoglobin release of horse erythrocytes. We show that the hydrophobic face of Cap18, in particular I13, L17 and I24, is essential for its antimicrobial activity against S. Typhimurium, Y. ruckeri, A. salmonicida, E. coli, P. aeruginosa, L. lactis, L. monocytogenes and E. faecalis. In particular, Cap18 derivatives harboring a I13D, L17D, L17P, I24D or I24N substitution lost their antimicrobial activity against any of the tested bacterial strains. In addition, we were able to generate species-specific Cap18 derivatives by particular amino acid substitutions either in the hydrophobic face at positions L6, L17, I20, and I27, or in the hydrophilic face at positions K16 and K18. Finally, our data showed the proline residue at position 29 to be essential for the inherent low hemolytic activity of Cap18 and that substitution of the residues K16, K23, or G21 by any hydrophobic residues enhances the hemolytic activity. This study demonstrates the potential of generating species-specific AMPs for the selective elimination of bacterial pathogens.

Synthesis, characterization, in vitro anti-proliferative and hemolytic activity of hydroxyapatite.

PubMed

Palanivelu, R; Ruban Kumar, A

2014-06-05

Hydroxyapatite (Ca10(PO4)6(OH)2, HAP) nanoparticles are widely used in several biomedical applications due to its compositional similarities to bone mineral, excellent biocompatibility and bioactivity, osteoconductivity. In this present investigation, HAP nanoparticles synthesized by precipitation technique using calcium nitrate and di-ammonium phosphate. The crystalline nature and the functional group analysis are confirmed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Fourier transform Raman spectroscopy (FT-Raman) respectively. The morphological observations are ascertained from field emission electron scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). In vitro anti-proliferative and hemolytic activities are carried out on the synthesized HAP samples and the studies reveals that HAP have mild activity against erythrocytes. Copyright © 2014 Elsevier B.V. All rights reserved.

Inhibitory role of acyl homoserine lactones in hemolytic activity and viability of Streptococcus pyogenes M6 S165

PubMed Central

Saroj, Sunil D.; Holmer, Linda; Berengueras, Júlia M.; Jonsson, Ann-Beth

2017-01-01

Streptococcus pyogenes an adapted human pathogen asymptomatically colonizes the nasopharynx, among other polymicrobial communities. However, information on the events leading to the colonization and expression of virulence markers subject to interspecies and host-bacteria interactions are limited. The interference of acyl homoserine lactones (AHLs) with the hemolytic activity and viability of S. pyogenes M6 S165 was examined. AHLs, with fatty acid side chains ≥12 carbon atoms, inhibited hemolytic activity by downregulating the expression of the sag operon involved in the production of streptolysin S. Inhibitory AHLs upregulated the expression of transcriptional regulator LuxR. Electrophoretic mobility shift assays revealed the interaction of LuxR with the region upstream of sagA. AHL-mediated bactericidal activity observed at higher concentrations (mM range) was an energy-dependent process, constrained by the requirement of glucose and iron. Ferrichrome transporter FtsABCD facilitated transport of AHLs across the streptococcal membrane. The study demonstrates a previously unreported role for AHLs in S. pyogenes virulence. PMID:28303956

Inhibitory role of acyl homoserine lactones in hemolytic activity and viability of Streptococcus pyogenes M6 S165.

PubMed

Saroj, Sunil D; Holmer, Linda; Berengueras, Júlia M; Jonsson, Ann-Beth

2017-03-17

Streptococcus pyogenes an adapted human pathogen asymptomatically colonizes the nasopharynx, among other polymicrobial communities. However, information on the events leading to the colonization and expression of virulence markers subject to interspecies and host-bacteria interactions are limited. The interference of acyl homoserine lactones (AHLs) with the hemolytic activity and viability of S. pyogenes M6 S165 was examined. AHLs, with fatty acid side chains ≥12 carbon atoms, inhibited hemolytic activity by downregulating the expression of the sag operon involved in the production of streptolysin S. Inhibitory AHLs upregulated the expression of transcriptional regulator LuxR. Electrophoretic mobility shift assays revealed the interaction of LuxR with the region upstream of sagA. AHL-mediated bactericidal activity observed at higher concentrations (mM range) was an energy-dependent process, constrained by the requirement of glucose and iron. Ferrichrome transporter FtsABCD facilitated transport of AHLs across the streptococcal membrane. The study demonstrates a previously unreported role for AHLs in S. pyogenes virulence.

The cholesterol-dependent cytolysins pneumolysin and streptolysin O require binding to red blood cell glycans for hemolytic activity

PubMed Central

Shewell, Lucy K.; Harvey, Richard M.; Higgins, Melanie A.; Day, Christopher J.; Hartley-Tassell, Lauren E.; Chen, Austen Y.; Gillen, Christine M.; James, David B. A.; Alonzo, Francis; Torres, Victor J.; Walker, Mark J.; Paton, Adrienne W.; Paton, James C.; Jennings, Michael P.

2014-01-01

The cholesterol-dependent cytolysin (CDC) pneumolysin (Ply) is a key virulence factor of Streptococcus pneumoniae. Membrane cholesterol is required for the cytolytic activity of this toxin, but it is not clear whether cholesterol is the only cellular receptor. Analysis of Ply binding to a glycan microarray revealed that Ply has lectin activity and binds glycans, including the Lewis histo-blood group antigens. Surface plasmon resonance analysis showed that Ply has the highest affinity for the sialyl LewisX (sLeX) structure, with a Kd of 1.88 × 10−5 M. Ply hemolytic activity against human RBCs showed dose-dependent inhibition by sLeX. Flow cytometric analysis and Western blots showed that blocking binding of Ply to the sLeX glycolipid on RBCs prevents deposition of the toxin in the membrane. The lectin domain responsible for sLeX binding is in domain 4 of Ply, which contains candidate carbohydrate-binding sites. Mutagenesis of these predicted carbohydrate-binding residues of Ply resulted in a decrease in hemolytic activity and a reduced affinity for sLeX. This study reveals that this archetypal CDC requires interaction with the sLeX glycolipid cellular receptor as an essential step before membrane insertion. A similar analysis conducted on streptolysin O from Streptococcus pyogenes revealed that this CDC also has glycan-binding properties and that hemolytic activity against RBCs can be blocked with the glycan lacto-N-neotetraose by inhibiting binding to the cell surface. Together, these data support the emerging paradigm shift that pore-forming toxins, including CDCs, have cellular receptors other than cholesterol that define target cell tropism. PMID:25422425

The cholesterol-dependent cytolysins pneumolysin and streptolysin O require binding to red blood cell glycans for hemolytic activity.

PubMed

Shewell, Lucy K; Harvey, Richard M; Higgins, Melanie A; Day, Christopher J; Hartley-Tassell, Lauren E; Chen, Austen Y; Gillen, Christine M; James, David B A; Alonzo, Francis; Torres, Victor J; Walker, Mark J; Paton, Adrienne W; Paton, James C; Jennings, Michael P

2014-12-09

The cholesterol-dependent cytolysin (CDC) pneumolysin (Ply) is a key virulence factor of Streptococcus pneumoniae. Membrane cholesterol is required for the cytolytic activity of this toxin, but it is not clear whether cholesterol is the only cellular receptor. Analysis of Ply binding to a glycan microarray revealed that Ply has lectin activity and binds glycans, including the Lewis histo-blood group antigens. Surface plasmon resonance analysis showed that Ply has the highest affinity for the sialyl LewisX (sLeX) structure, with a K(d) of 1.88 × 10(-5) M. Ply hemolytic activity against human RBCs showed dose-dependent inhibition by sLeX. Flow cytometric analysis and Western blots showed that blocking binding of Ply to the sLeX glycolipid on RBCs prevents deposition of the toxin in the membrane. The lectin domain responsible for sLeX binding is in domain 4 of Ply, which contains candidate carbohydrate-binding sites. Mutagenesis of these predicted carbohydrate-binding residues of Ply resulted in a decrease in hemolytic activity and a reduced affinity for sLeX. This study reveals that this archetypal CDC requires interaction with the sLeX glycolipid cellular receptor as an essential step before membrane insertion. A similar analysis conducted on streptolysin O from Streptococcus pyogenes revealed that this CDC also has glycan-binding properties and that hemolytic activity against RBCs can be blocked with the glycan lacto-N-neotetraose by inhibiting binding to the cell surface. Together, these data support the emerging paradigm shift that pore-forming toxins, including CDCs, have cellular receptors other than cholesterol that define target cell tropism.

Oxidative stress-mediated hemolytic activity of solvent exchange-prepared fullerene (C60) nanoparticles

NASA Astrophysics Data System (ADS)

Trpkovic, Andreja; Todorovic-Markovic, Biljana; Kleut, Duska; Misirkic, Maja; Janjetovic, Kristina; Vucicevic, Ljubica; Pantovic, Aleksandar; Jovanovic, Svetlana; Dramicanin, Miroslav; Markovic, Zoran; Trajkovic, Vladimir

2010-09-01

The present study investigated the hemolytic properties of fullerene (C60) nanoparticles prepared by solvent exchange using tetrahydrofuran (nC60THF), or by mechanochemically assisted complexation with macrocyclic oligosaccharide gamma-cyclodextrin (nC60CDX) or the copolymer ethylene vinyl acetate-ethylene vinyl versatate (nC60EVA-EVV). The spectrophotometrical analysis of hemoglobin release revealed that only nC60THF, but not nC60CDX or nC60EVA-EVV, was able to cause lysis of human erythrocytes in a dose- and time-dependent manner. Atomic force microscopy revealed that nC60THF-mediated hemolysis was preceded by erythrocyte shrinkage and increase in cell surface roughness. A flow cytometric analysis confirmed a decrease in erythrocyte size and demonstrated a significant increase in reactive oxygen species production in red blood cells exposed to nC60THF. The nC60THF-triggered hemolytic activity was efficiently reduced by the antioxidants N-acetylcysteine and butylated hydroxyanisole, as well as by serum albumin, the most abundant protein in human blood plasma. These data indicate that nC60THF can cause serum albumin-preventable hemolysis through oxidative stress-mediated damage of the erythrocyte membrane.

Design and Application of Multifunctional DNA Nanocarriers for Therapeutic Delivery

PubMed Central

Charoenphol, Phapanin; Bermudez, Harry

2013-01-01

The unique programmability of nucleic acids offers versatility and flexibility in the creation of self-assembled DNA nanostructures. To date, many three-dimensional DNA architectures have been precisely formed of varying sizes and shapes. Their biocompatibility, biodegradability, and high intrinsic stability in physiological environments emphasize their emerging use as carriers for drug and gene delivery. Furthermore, DNA nanocarriers have been shown to enter cells efficiently and without the aid of transfection reagents. A key strength of DNA nanocarriers over other delivery systems is their modularity and their ability to control the spatial distribution of cargoes and ligands. Optimizing DNA nanocarrier properties to dictate their localization, uptake, and intracellular trafficking is also possible. In this review, we present design considerations for DNA nanocarriers and examples of their use in the context of therapeutic delivery applications. The assembly of DNA nanocarriers and approaches for loading and releasing cargo are described. The stability and safety of DNA nanocarriers is also discussed, with particular attention to the in vivo physiological environment. Mechanisms of cellular uptake and intracellular trafficking are examined, and we conclude with strategies to enhance the delivery efficiency of DNA nanocarriers. PMID:23896566

PSMA-Targeted Theranostic Nanocarrier for Prostate Cancer

PubMed Central

Flores, Orielyz; Santra, Santimukul; Kaittanis, Charalambos; Bassiouni, Rania; Khaled, Amr S; Khaled, Annette R.; Grimm, Jan; Perez, J Manuel

2017-01-01

Herein, we report the use of a theranostic nanocarrier (Folate-HBPE(CT20p)) to deliver a therapeutic peptide to prostate cancer tumors that express PSMA (folate hydrolase 1). The therapeutic peptide (CT20p) targets and inhibits the chaperonin-containing TCP-1 (CCT) protein-folding complex, is selectively cytotoxic to cancer cells, and is non-toxic to normal tissue. With the delivery of CT20p to prostate cancer cells via PSMA, a dual level of cancer specificity is achieved: (1) selective targeting to PSMA-expressing prostate tumors, and (2) specific cytotoxicity to cancer cells with minimal toxicity to normal cells. The PSMA-targeting theranostic nanocarrier can image PSMA-expressing cells and tumors when a near infrared dye is used as cargo. Meanwhile, it can be used to treat PSMA-expressing tumors when a therapeutic, such as the CT20p peptide, is encapsulated within the nanocarrier. Even when these PSMA-targeting nanocarriers are taken up by macrophages, minimal cell death is observed in these cells, in contrast with doxorubicin-based therapeutics that result in significant macrophage death. Incubation of PSMA-expressing prostate cancer cells with the Folate-HBPE(CT20p) nanocarriers induces considerable changes in cell morphology, reduction in the levels of integrin β1, and lower cell adhesion, eventually resulting in cell death. These results are relevant as integrin β1 plays a key role in prostate cancer invasion and metastatic potential. In addition, the use of the developed PSMA-targeting nanocarrier facilitates the selective in vivo delivery of CT20p to PSMA-positive tumor, inducing significant reduction in tumor size. PMID:28744329

The dinoflagellate Akashiwo sanguinea will benefit from future climate change: The interactive effects of ocean acidification, warming and high irradiance on photophysiology and hemolytic activity.

PubMed

Ou, Guanyong; Wang, Hong; Si, Ranran; Guan, Wanchun

2017-09-01

Due to global climate change, marine phytoplankton will likely experience low pH (ocean acidification), high temperatures and high irradiance in the future. Here, this work report the results of a batch culture experiment conducted to study the interactive effects of elevated CO 2 , increased temperature and high irradiance on the harmful dinoflagellate Akashiwo sanguinea, isolated at Dongtou Island, Eastern China Sea. The A. sanguinea cells were acclimated in high CO 2 condition for about three months before testing the responses of cells to a full factorial matrix experimentation during a 7-day period. This study measured the variation in physiological parameters and hemolytic activity in 8 treatments, representing full factorial combinations of 2 levels each of exposure to CO 2 (400 and 1000μatm), temperature (20 and 28°C) and irradiance (50 and 200μmol photons m -2 s -1 ). Sustained growth of A. sanguinea occurred in all treatments, but high CO 2 (HC) stimulated faster growth than low CO 2 (LC). The pigments (chlorophyll a and carotenoid) decreased in all HC treatments. The quantum yield (F v /F m ) declined slightly in all high-temperature (HT) treatments. High irradiance (HL) induced the accumulation of ultraviolet-absorbing compounds (UV abc ) irrespective of temperature and CO 2 . The hemolytic activity in the LC treatments, however, declined when exposed to HT and HL, but HC alleviated the adverse effects of HT and HL on hemolytic activity. All HC and HL conditions and the combinations of high temperature*high light (HTHL) and high CO 2 *high temperature*high light (HCHTHL) positively affected the growth in comparison to the low CO 2 *low temperature*low light (LCLTLL) treatment. High temperature (HT), high light (HL) and a combination of HT*HL, however, negatively impacted hemolytic activity. CO 2 was the main factor that affected the growth and hemolytic activity. There were no significant interactive effects of CO 2 *temperature*irradiance on growth

Hemolytic, anticancer and antigiardial activity of Palythoa caribaeorum venom.

PubMed

Lazcano-Pérez, Fernando; Zavala-Moreno, Ariana; Rufino-González, Yadira; Ponce-Macotela, Martha; García-Arredondo, Alejandro; Cuevas-Cruz, Miguel; Gómez-Manzo, Saúl; Marcial-Quino, Jaime; Arreguín-Lozano, Barbarín; Arreguín-Espinosa, Roberto

2018-01-01

Cnidarian venoms and extracts have shown a broad variety of biological activities including cytotoxic, antibacterial and antitumoral effects. Most of these studied extracts were obtained from sea anemones or jellyfish. The present study aimed to determine the toxic activity and assess the antitumor and antiparasitic potential of Palythoa caribaeorum venom by evaluating its in vitro toxicity on several models including human tumor cell lines and against the parasite Giardia intestinalis . The presence of cytolysins and vasoconstrictor activity of P. caribaeorum venom were determined by hemolysis, PLA 2 and isolated rat aortic ring assays, respectively. The cytotoxic effect was tested on HCT-15 (human colorectal adenocarcinoma), MCF-7 (human mammary adenocarcinoma), K562 (human chronic myelogenous leukemia), U251 (human glyoblastoma), PC-3 (human prostatic adenocarcinoma) and SKLU-1 (human lung adenocarcinoma). An in vivo toxicity assay was performed with crickets and the antiparasitic assay was performed against G. intestinalis at 24 h of incubation. P. caribaeorum venom produced hemolytic and PLA 2 activity and showed specific cytotoxicity against U251 and SKLU-1 cell lines, with approximately 50% growing inhibition. The venom was toxic to insects and showed activity against G. intestinalis in a dose-dependent manner by possibly altering its membrane osmotic equilibrium. These results suggest that P. caribaeorum venom contains compounds with potential therapeutic value against microorganisms and cancer.

Characterization of plasma labile heme in hemolytic conditions

PubMed Central

Gouveia, Zélia; Carlos, Ana R.; Yuan, Xiaojing; Aires-da-Silva, Frederico; Stocker, Roland; Maghzal, Ghassan J.; Leal, Sónia S.; Gomes, Cláudio M.; Todorovic, Smilja; Iranzo, Olga; Ramos, Susana; Santos, Ana C.; Hamza, Iqbal; Gonçalves, João; Soares, Miguel P.

2018-01-01

Extracellular hemoglobin, a byproduct of hemolysis, can release its prosthetic heme groups upon oxidation. This produces metabolically active heme that is exchangeable between acceptor proteins, macromolecules and low molecular weight ligands, termed here labile heme. As it accumulates in plasma labile heme acts in a pro-oxidant manner and regulates cellular metabolism while exerting pro-inflammatory and cytotoxic effects that foster the pathogenesis of hemolytic diseases. Here, we developed and characterized a panel of heme-specific single domain antibodies (sdAbs) that together with a cellular-based heme reporter assay, allow for quantification and characterization of labile heme in plasma during hemolytic conditions. Using these approaches, we demonstrate that when generated during hemolytic conditions labile heme is bound to plasma molecules with an affinity higher than 10−7 m and that 2–8% (∼ 2–5 μm) of the total amount of heme detected in plasma can be internalized by bystander cells, termed here bioavailable heme. Acute, but not chronic, hemolysis is associated with transient reduction of plasma heme-binding capacity, that is, the ability of plasma molecules to bind labile heme with an affinity higher than 10−7 m. The heme-specific sdAbs neutralize the pro-oxidant activity of soluble heme in vitro, suggesting that these maybe used to counter the pathologic effects of labile heme during hemolytic conditions. Finally, we show that heme-specific sdAbs can be used to visualize cellular heme. In conclusion, we describe a panel of heme-specific sdAbs that when used with other approaches provide novel insights to the pathophysiology of heme. PMID:28783254

Nanocarriers in advanced drug targeting: setting novel paradigm in cancer therapeutics.

PubMed

Akhter, Md Habban; Rizwanullah, Md; Ahmad, Javed; Ahsan, Mohamed Jawed; Mujtaba, Md Ali; Amin, Saima

2018-08-01

Cancer has been growing nowadays consequently high number of death ascertained worldwide. The medical intervention involves chemotherapy, radiation therapy and surgical removal. This conventional technique lacking targeting potential and harm the normal cells. In drug treatment regimen, the combination therapy is preferred than single drug treatment module due to higher internalization of chemotherapeutics in the cancer cells both by enhance permeation retention effect and by direct cell apoptosis. The cancer therapeutics involves different methodologies of delivering active moiety to the target site. The active and passive transport mode of chemotherapeutic targeting utilizes advance nanocarriers. The nanotechnological strategic treatment applying advance nanocarrier greatly helps in mitigating the cancer prevalence. The nanocarrier-incorporating nanodrug directed for specific area appealed scientist across the globe and issues to be addressed in this regard. Therefore, various techniques and approaches invented to meet the objectives. With the advances in nanomedicine and drug delivery, this review briefly focused on various modes of nanodrug delivery including nanoparticles, liposomes, dendrimer, quantum dots, carbon nanotubes, metallic nanoparticles, nanolipid carrier (NLC), gold nanoshell, nanosize cantilevers and nanowire that looks promising and generates a novel horizon in cancer therapeutics.

Reversibly crosslinked nanocarriers for on-demand drug delivery in cancer treatment

PubMed Central

Shao, Yu; Huang, Wenzhe; Shi, Changying; Atkinson, Sean T; Luo, Juntao

2013-01-01

Polymer micelles have proven to be one of the most versatile nanocarriers for anticancer drug delivery. However, the in vitro and in vivo stability of micelles remains a challenge due to the dynamic nature of these self-assembled systems, which leads to premature drug release and nonspecific biodistribution in vivo. Recently, reversibly crosslinked micelles have been developed to provide solutions to stabilize nanocarriers in blood circulation. Increased stability allows nanoparticles to accumulate at tumor sites efficiently via passive and/or active tumor targeting, while cleavage of the micelle crosslinkages, through internal or external stimuli, facilitates on-demand drug release. In this review, various crosslinking chemistries as well as the choices for reversible linkages in these nanocarriers will be introduced. Then, the development of reversibly crosslinked micelles for on-demand drug release in response to single or dual stimuli in the tumor microenvironment is discussed, for example, acidic pH, reducing microenvironment, enzymatic microenvironment, photoirradiation and the administration of competitive reagents postmicelle delivery. PMID:23323559

Isolation and in vitro partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish Stomolophus meleagris.

PubMed

Li, Rongfeng; Yu, Huahua; Xing, Ronge; Liu, Song; Qing, Yukun; Li, Kecheng; Li, Bing; Meng, Xiangtao; Cui, Jinhui; Li, Pengcheng

2013-09-01

Jellyfish venom contains various toxins and can cause itching, edema, muscle aches, shortness of breath, blood pressure depression, shock or even death after being stung. Hemolytic protein is one of the most hazardous components in the venom. The present study investigated the hemolytic activity of the nematocyst venom from jellyfish Stomolophus meleagris. Anion exchange chromatography, DEAE Sepharose Fast Flow, and gel filtration chromatography, Superdex200 had been employed to isolate hemolytic proteins from the nematocyst venom of jellyfish S. meleagris. Hemolysis of chicken red blood cells was used to quantify hemolytic potency of crude nematocyst venom and chromatography fractions during the purification process. Native-PAGE profile displayed one protein band in the purified hemolytic protein (SmTX); however, two protein bands with apparent molecular weights of ≈ 45 kDa and 52 kDa were observed in the reducing SDS-PAGE analysis. Approximately 70 μg/mL of SmTX caused 50% hemolysis (HU50) of the erythrocyte suspension. The hemolytic activity of SmTX was shown to be temperature and pH dependent, with the optimum temperature and pH being 37°C and pH 5.0. The present study is the first report of isolation and partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish S. meleagris. The mechanism of the hemolytic activity of SmTX is not clear and deserves further investigation. Copyright © 2013. Published by Elsevier Ltd.

Hemolytic Anemia

MedlinePlus

... t known. AIHA accounts for half of all cases of hemolytic anemia. AIHA may come on very quickly and become serious. Having certain diseases or infections can raise your risk for AIHA. Examples include: Autoimmune diseases, such as lupus Chronic lymphocytic ...

Development of mannose-anchored thiolated amphotericin B nanocarriers for treatment of visceral leishmaniasis.

PubMed

Shahnaz, Gul; Edagwa, Benson J; McMillan, JoEllyn; Akhtar, Sohail; Raza, Abida; Qureshi, Naveeda A; Yasinzai, Masoom; Gendelman, Howard E

2017-01-01

Our goal was to improve treatment outcomes for visceral leishmaniasis by designing nanocarriers that improve drug biodistribution and half-life. Thus, long-acting mannose-anchored thiolated chitosan amphotericin B nanocarrier complexes (MTC AmB) were developed and characterized. A mannose-anchored thiolated chitosan nanocarrier was manufactured and characterized. MTC AmB was examined for cytotoxicity, biocompatibility, uptake and antimicrobial activities. MTC AmB was rod shaped with a size of 362 nm. MTC AmB elicited 90% macrophage viability and 71-fold enhancement in drug uptake compared with native drug. The antileishmanial IC 50 for MTC AmB was 0.02 μg/ml compared with 0.26 μg/ml for native drug. These studies show that MTC can serve as a platform for clearance of Leishmania in macrophages.

Effects of co-existing microalgae and grazers on the production of hemolytic toxins in Karenia mikimotoi

NASA Astrophysics Data System (ADS)

Yang, Weidong; Zhang, Naisheng; Cui, Weimin; Xu, Yanyan; Li, Hongye; Liu, Jiesheng

2011-11-01

Karenia mikimotoi (Miyake & Kominami ex Oda) Hansen & Moestrup is associated with harmful algal blooms in temperate and subtropical zones of the world. The hemolytic substances produced by K. mikimotoi are thought to cause mortality in fishes and invertebrates. We evaluated the composition of the hemolytic toxin produced by K. mikimotoi cultured in the laboratory using thin-layer chromatography. In addition, we evaluated the effect of co-occuring algae ( Prorocentrum donghaiense and Alexandrium tamarense) and the cladoceran grazer Moina mongolica on hemolytic toxin production in K. mikimotoi. The hemolytic toxins from K. mikimotoi were a mixture of 2 liposaccharides and 1 lipid. Waterborne clues from P. donghaiense and A. tamarense inhibited the growth of K. mikimotoi but increased the production of hemolytic toxins. Conversely, K. mikimotoi strongly inhibited the growth of caged P. donghaiense and A. tamarense. In addition, the ingestion of K. mikimotoi by M. mongolica induced the production of hemolytic toxins in K. mikimotoi. Taken together, our results suggest that the presence of other microalgae and grazers may be as important as environmental factors for controlling the production of hemolytic substances. K. mikimotoi secreted allelochemicals other than unstable fatty acids with hemolytic activity. The production of hemolytic toxins in dinoflagellates was not only dependent on resource availability, but also on the risk of predation. Hemolytic toxins likely play an important role as chemical deterrents secreted by K. mikimotoi.

Optimization of cell receptor-specific targeting through multivalent surface decoration of polymeric nanocarriers

PubMed Central

D’Addio, Suzanne M.; Baldassano, Steven; Shi, Lei; Cheung, Lila; Adamson, Douglas H.; Bruzek, Matthew; Anthony, John E.; Laskin, Debra L.; Sinko, Patrick J.; Prud’homme, Robert K.

2013-01-01

Treatment of tuberculosis is impaired by poor drug bioavailability, systemic side effects, patient non-compliance, and pathogen resistance to existing therapies. The mannose receptor (MR) is known to be involved in the recognition and internalization of Mycobacterium tuberculosis. We present a new assembly process to produce nanocarriers with variable surface densities of mannose targeting ligands in a single step, using kinetically-controlled, block copolymer-directed assembly. Nanocarrier association with murine macrophage J774 cells expressing the MR is examined as a function of incubation time and temperature, nanocarrier size, dose, and PEG corona properties. Amphiphilic diblock copolymers are prepared with terminal hydroxyl, methoxy, or mannoside functionality and incorporated into nanocarrier formulations at specific ratios by Flash NanoPrecipitation. Association of nanocarriers protected by a hydroxyl-terminated PEG corona with J774 cells is size dependent, while nanocarriers with methoxy-terminated PEG coronas do not associate with cells, regardless of size. Specific targeting of the MR is investigated using nanocarriers having 0-75% mannoside-terminated PEG chains in the PEG corona. This is a wider range of mannose densities than has been previously studied. Maximum nanocarrier association is attained with 9% mannoside-terminated PEG chains, increasing uptake more than 3-fold compared to non-targeted nanocarriers with a 5 kg mol−1 methoxy-terminated PEG corona. While a 5 kg mol−1 methoxy-terminated PEG corona prevents non-specific uptake, a 1.8 kg mol−1 methoxy-terminated PEG corona does not sufficiently protect the nanocarriers from nonspecific association. There is continuous uptake of MR-targeted nanocarriers at 37°C, but a saturation of association at 4°C. The majority of targeted nanocarriers associate with J774E cells are internalized at 37°C and uptake is receptor-dependent, diminishing with competitive inhibition by dextran. This

Transferrin-Conjugated Nanocarriers as Active-Targeted Drug Delivery Platforms for Cancer Therapy.

PubMed

Nogueira-Librelotto, Daniele R; Codevilla, Cristiane F; Farooqi, Ammad; Rolim, Clarice M B

2017-01-01

A lot of effort has been devoted to achieving active targeting for cancer therapy in order to reach the right cells. Hence, increasingly it is being realized that active-targeted nanocarriers notably reduce off-target effects, mainly because of targeted localization in tumors and active cellular uptake. In this context, by taking advantage of the overexpression of transferrin receptors on the surface of tumor cells, transferrin-conjugated nanodevices have been designed, in hope that the biomarker grafting would help to maximize the therapeutic benefit and to minimize the side effects. Notably, active targeting nanoparticles have shown improved therapeutic performances in different tumor models as compared to their passive targeting counterparts. In this review, current development of nano-based devices conjugated with transferrin for active tumor-targeting drug delivery are highlighted and discussed. The main objective of this review is to provide a summary of the vast types of nanomaterials that have been used to deliver different chemotherapeutics into tumor cells, and to ultimately evaluate the progression on the strategies for cancer therapy in view of the future research. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Cationic nanocarriers induce cell necrosis through impairment of Na+/K+-ATPase and cause subsequent inflammatory response

PubMed Central

Wei, Xiawei; Shao, Bin; He, Zhiyao; Ye, Tinghong; Luo, Min; Sang, Yaxiong; Liang, Xiao; Wang, Wei; Luo, Shuntao; Yang, Shengyong; Zhang, Shuang; Gong, Changyang; Gou, Maling; Deng, Hongxing; Zhao, Yinglan; Yang, Hanshuo; Deng, Senyi; Zhao, Chengjian; Yang, Li; Qian, Zhiyong; Li, Jiong; Sun, Xun; Han, Jiahuai; Jiang, Chengyu; Wu, Min; Zhang, Zhirong

2015-01-01

Nanocarriers with positive surface charges are known for their toxicity which has limited their clinical applications. The mechanism underlying their toxicity, such as the induction of inflammatory response, remains largely unknown. In the present study we found that injection of cationic nanocarriers, including cationic liposomes, PEI, and chitosan, led to the rapid appearance of necrotic cells. Cell necrosis induced by cationic nanocarriers is dependent on their positive surface charges, but does not require RIP1 and Mlkl. Instead, intracellular Na+ overload was found to accompany the cell death. Depletion of Na+ in culture medium or pretreatment of cells with the Na+/K+-ATPase cation-binding site inhibitor ouabain, protected cells from cell necrosis. Moreover, treatment with cationic nanocarriers inhibited Na+/K+-ATPase activity both in vitro and in vivo. The computational simulation showed that cationic carriers could interact with cation-binding site of Na+/K+-ATPase. Mice pretreated with a small dose of ouabain showed improved survival after injection of a lethal dose of cationic nanocarriers. Further analyses suggest that cell necrosis induced by cationic nanocarriers and the resulting leakage of mitochondrial DNA could trigger severe inflammation in vivo, which is mediated by a pathway involving TLR9 and MyD88 signaling. Taken together, our results reveal a novel mechanism whereby cationic nanocarriers induce acute cell necrosis through the interaction with Na+/K+-ATPase, with the subsequent exposure of mitochondrial damage-associated molecular patterns as a key event that mediates the inflammatory responses. Our study has important implications for evaluating the biocompatibility of nanocarriers and designing better and safer ones for drug delivery. PMID:25613571

Candida tropicalis from veterinary and human sources shows similar in vitro hemolytic activity, antifungal biofilm susceptibility and pathogenesis against Caenorhabditis elegans.

PubMed

Brilhante, Raimunda Sâmia Nogueira; Oliveira, Jonathas Sales de; Evangelista, Antônio José de Jesus; Serpa, Rosana; Silva, Aline Lobão da; Aguiar, Felipe Rodrigues Magalhães de; Pereira, Vandbergue Santos; Castelo-Branco, Débora de Souza Collares Maia; Pereira-Neto, Waldemiro Aquino; Cordeiro, Rossana de Aguiar; Sidrim, José Júlio Costa; Rocha, Marcos Fábio Gadelha

2016-08-30

The aim of this study was to evaluate the in vitro hemolytic activity and biofilm antifungal susceptibility of veterinary and human Candida tropicalis strains, as well as their pathogenesis against Caenorhabditis elegans. Twenty veterinary isolates and 20 human clinical isolates of C. tropicalis were used. The strains were evaluated for their hemolytic activity and biofilm production. Biofilm susceptibility to itraconazole, fluconazole, voriconazole, amphotericin B and caspofungin was assessed using broth microdilution assay. The in vivo evaluation of strain pathogenicity was investigated using the nematode C. elegans. Hemolytic factor was observed in 95% of the strains and 97.5% of the isolates showed ability to form biofilm. Caspofungin and amphotericin B showed better results than azole antifungals against mature biofilms. Paradoxical effect on mature biofilm metabolic activity was observed at elevated concentrations of caspofungin (8-64μg/mL). Azole antifungals were not able to inhibit mature C. tropicalis biofilms, even at the higher tested concentrations. High mortality rates of C. elegans were observed when the worms were exposed to with C. tropicalis strains, reaching up to 96%, 96h after exposure of the worms to C. tropicalis strains. These results reinforce the high pathogenicity of C. tropicalis from veterinary and human sources and show the effectiveness of caspofungin and amphotericin B against mature biofilms of this species. Copyright © 2016 Elsevier B.V. All rights reserved.

Plasmonic nanocarrier grid-enhanced Raman sensor for studies of anticancer drug delivery.

PubMed

Kurzątkowska, Katarzyna; Santiago, Ty; Hepel, Maria

2017-05-15

Targeted drug delivery systems using nanoparticle nanocarriers offer remarkable promise for cancer therapy by discriminating against devastating cytotoxicity of chemotherapeutic drugs to healthy cells. To aid in the development of new drug nanocarriers, we propose a novel plasmonic nanocarrier grid-enhanced Raman sensor which can be applied for studies and testing of drug loading onto the nanocarriers, attachment of targeting ligands, dynamics of drug release, assessment of nanocarrier stability in biological environment, and general capabilities of the nanocarrier. The plasmonic nanogrid sensor offers strong Raman enhancement due to the overlapping plasmonic fields emanating from the nearest-neighbor gold nanoparticle nanocarriers and creating the enhancement "hot spots". The sensor has been tested for immobilization of an anticancer drug gemcitabine (2',2'-difluoro-2'-deoxycytidine, GEM) which is used in treatment of pancreatic tumors. The drawbacks of currently applied treatment include high systemic toxicity, rapid drug decay, and low efficacy (ca. 20%). Therefore, the development of a targeted GEM delivery system is highly desired. We have demonstrated that the proposed nanocarrier SERS sensor can be utilized to investigate attachment of targeting ligands to nanocarriers (attachment of folic acid ligand recognized by folate receptors of cancer cells is described). Further testing of the nanocarrier SERS sensor involved drug release induced by lowering pH and increasing GSH levels, both occurring in cancer cells. The proposed sensor can be utilized for a variety of drugs and targeting ligands, including those which are Raman inactive, since the linkers can act as the Raman markers, as illustrated with mercaptobenzoic acid and para-aminothiophenol. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of mannose-anchored thiolated amphotericin B nanocarriers for treatment of visceral leishmaniasis

PubMed Central

Shahnaz, Gul; Edagwa, Benson J; McMillan, JoEllyn; Akhtar, Sohail; Raza, Abida; Qureshi, Naveeda A; Yasinzai, Masoom; Gendelman, Howard E

2017-01-01

Aim: Our goal was to improve treatment outcomes for visceral leishmaniasis by designing nanocarriers that improve drug biodistribution and half-life. Thus, long-acting mannose-anchored thiolated chitosan amphotericin B nanocarrier complexes (MTC AmB) were developed and characterized. Materials & methods: A mannose-anchored thiolated chitosan nanocarrier was manufactured and characterized. MTC AmB was examined for cytotoxicity, biocompatibility, uptake and antimicrobial activities. Results: MTC AmB was rod shaped with a size of 362 nm. MTC AmB elicited 90% macrophage viability and 71-fold enhancement in drug uptake compared with native drug. The antileishmanial IC50 for MTC AmB was 0.02 μg/ml compared with 0.26 μg/ml for native drug. Conclusion: These studies show that MTC can serve as a platform for clearance of Leishmania in macrophages. PMID:27879160

Lecithin-based novel cationic nanocarriers (LeciPlex) I: fabrication, characterization and evaluation.

PubMed

Date, Abhijit A; Srivastava, Deepika; Nagarsenker, Mangal S; Mulherkar, Rita; Panicker, Lata; Aswal, Vinod; Hassan, Puthusserickal A; Steiniger, Frank; Thamm, Jana; Fahr, Alfred

2011-10-01

In the present investigation, the feasibility of fabricating novel self-assembled cationic nanocarriers (LeciPlex) containing cetyltrimethylammonium bromide (CTAB) or didodecyldimethylammonium bromide (DDAB) and soybean lecithin using pharmaceutically acceptable biocompatible solvents such as 2-Pyrrolidone (Soluphor P) and diethyleneglycol monoethyl ether (Transcutol) was established. The interaction between DDAB/CTAB and soybean lecithin in the nanocarriers was confirmed by differential scanning calorimetry and in vitro antimicrobial studies. The positive charge on the nanocarriers was confirmed by zeta potential analysis. Transmission electron microscopy analysis could not reveal sufficient information regarding the internal structure of the nanocarriers, whereas cryotransmission electron microscopy studies indicated that these novel nanocarriers have unilamellar structure. Small-angle neutron scattering studies confirmed interaction of cationic surfactant (DDAB) and lecithin in the nanocarriers and confirmed the presence of unilamellar nanostructures. Various hydrophobic drugs could be encapsulated in the CTAB/DDAB-based lecithin nanocarriers (CTAB-LeciPlex or DDAB-LeciPlex) irrespective of their difference in log p-values. In vitro antimicrobial studies on triclosan-loaded LeciPlex confirmed entrapment of triclosan in the nanocarriers. The ability of CTAB-LeciPlex and DDAB-LeciPlex to condense plasmid DNA was established using agarose gel electrophoresis. DDAB-LeciPlex could successfully transfect pDNA in HEK-293 cells indicating potential in gene delivery.

Formulation, Quality Control and Safety Issues of Nanocarriers Used for Cancer Treatment.

PubMed

Bianco, Ismael D; Ceballos, Marcelo R; Casado, Cristian; Dabbene, Viviana G; Rizzi, Carolina; Mizutamari, R Kiyomi

2017-01-01

Cancer is becoming a leading cause of death in the last years. Although we have seen great advances, most human cancers remain incurable because many patients either do not respond or relapse to treatment. Several lines of research are disclosing new therapeutic targets which lead to new active drugs. However, there are still unsolved problems related to stabilization of the pharmaceutical ingredient in aqueous and biological media, pharmacokinetic and pharmacodynamic profiles and cellular uptake to name just a few. In this context, nanotechnology with the emerging tools of nanoengineering offers many possibilities to guide the design of new products with improved safety and efficacy. The presence of several reacting groups and the sensitivity of their properties to small changes in composition make nanocarriers tunable not only to modify their stability in a particular environment but also to respond to changes in biological situations in the right place and time frame. This review summarizes the main preparation methods and formulation strategies of nano and microcarriers designed for drug delivery applications for cancer treatment and will attempt to give a glimpse on how their structure, shape, physico-chemical properties and chemical composition may affect their overall stability and interactions with biological systems. We will also cover aspects of nanoengineering that are opening new opportunities for the development of more effective nanomedicines, emphasizing on the challenges that have to be kept in mind when dealing with biological activities of nanocarriers that depend not only on their chemical composition but also on those of the structures formed by them and by their interactions with biological systems. From this, a very important issue that emerges is that nanocarriers frequently display an intrinsic bioactivity (i.e.: immunomodulatory). Therefore, it should be stressed that nanocarriers cannot be considered as inert, biocompatible excipients

A Novel Quantitative Hemolytic Assay Coupled with Restriction Fragment Length Polymorphisms Analysis Enabled Early Diagnosis of Atypical Hemolytic Uremic Syndrome and Identified Unique Predisposing Mutations in Japan

PubMed Central

Yoshida, Yoko; Miyata, Toshiyuki; Matsumoto, Masanori; Shirotani-Ikejima, Hiroko; Uchida, Yumiko; Ohyama, Yoshifumi; Kokubo, Tetsuro; Fujimura, Yoshihiro

2015-01-01

For thrombotic microangiopathies (TMAs), the diagnosis of atypical hemolytic uremic syndrome (aHUS) is made by ruling out Shiga toxin-producing Escherichia coli (STEC)-associated HUS and ADAMTS13 activity-deficient thrombotic thrombocytopenic purpura (TTP), often using the exclusion criteria for secondary TMAs. Nowadays, assays for ADAMTS13 activity and evaluation for STEC infection can be performed within a few hours. However, a confident diagnosis of aHUS often requires comprehensive gene analysis of the alternative complement activation pathway, which usually takes at least several weeks. However, predisposing genetic abnormalities are only identified in approximately 70% of aHUS. To facilitate the diagnosis of complement-mediated aHUS, we describe a quantitative hemolytic assay using sheep red blood cells (RBCs) and human citrated plasma, spiked with or without a novel inhibitory anti-complement factor H (CFH) monoclonal antibody. Among 45 aHUS patients in Japan, 24% (11/45) had moderate-to-severe (≥50%) hemolysis, whereas the remaining 76% (34/45) patients had mild or no hemolysis (<50%). The former group is largely attributed to CFH-related abnormalities, and the latter group has C3-p.I1157T mutations (16/34), which were identified by restriction fragment length polymorphism (RFLP) analysis. Thus, a quantitative hemolytic assay coupled with RFLP analysis enabled the early diagnosis of complement-mediated aHUS in 60% (27/45) of patients in Japan within a week of presentation. We hypothesize that this novel quantitative hemolytic assay would be more useful in a Caucasian population, who may have a higher proportion of CFH mutations than Japanese patients. PMID:25951460

Fully glutathione degradable waterborne polyurethane nanocarriers: Preparation, redox-sensitivity, and triggered intracellular drug release.

PubMed

Omrani, Ismail; Babanejad, Niloofar; Shendi, Hasan Kashef; Nabid, Mohammad Reza

2017-01-01

Polyurethanes are important class of biomaterials that are extensively used in medical devices. In spite of their easy synthesis, polyurethanes that are fully degradable in response to the intracellular reducing environment are less explored for controlled drug delivery. Herein, a novel glutathione degradable waterborne polyurethane (WPU) nanocarrier for redox triggered intracellular delivery of a model lipophilic anticancer drug, doxorubicin (DOX) is reported. The WPU was prepared from polyaddition reaction of isophorone diisocyanate (IPDI) and a novel linear polyester polyol involving disulfide linkage, disulfide labeled chain extender, dimethylolpropionic acid (DMPA) using dibutyltin dilaurate (DBTDL) as a catalyst. The resulting polyurethane self-assembles into nanocarrier in water. The dynamic light scattering (DLS) measurements and scanning electron microscope (SEM) revealed fast swelling and disruption of nanocarriers under an intracellular reduction-mimicking environment. The in vitro release studies showed that DOX was released in a controlled and redox-dependent manner. MTT assays showed that DOX-loaded WPU had a high in vitro antitumor activity in both HDF noncancer cells and MCF- 7 cancer cells. In addition, it is found that the blank WPU nanocarriers are nontoxic to HDF and MCF-7 cells even at a high concentration of 2mg/mL. Hence, nanocarriers based on disulfide labeled WPU have appeared as a new class of biocompatible and redox-degradable nanovehicle for efficient intracellular drug delivery. Copyright © 2016 Elsevier B.V. All rights reserved.

Genetics Home Reference: atypical hemolytic-uremic syndrome

MedlinePlus

... Kidney Diseases: Kidney Failure: Choosing a Treatment That's Right for You Educational Resources (6 links) Disease InfoSearch: Hemolytic uremic syndrome, atypical MalaCards: genetic atypical hemolytic-uremic syndrome Merck Manual Consumer Version: Overview of Anemia Merck Manual Consumer Version: ...

Hemolytic potential of hydrodynamic cavitation.

PubMed

Chambers, S D; Bartlett, R H; Ceccio, S L

2000-08-01

The purpose of this study was to determine the hemolytic potentials of discrete bubble cavitation and attached cavitation. To generate controlled cavitation events, a venturigeometry hydrodynamic device, called a Cavitation Susceptibility Meter (CSM), was constructed. A comparison between the hemolytic potential of discrete bubble cavitation and attached cavitation was investigated with a single-pass flow apparatus and a recirculating flow apparatus, both utilizing the CSM. An analytical model, based on spherical bubble dynamics, was developed for predicting the hemolysis caused by discrete bubble cavitation. Experimentally, discrete bubble cavitation did not correlate with a measurable increase in plasma-free hemoglobin (PFHb), as predicted by the analytical model. However, attached cavitation did result in significant PFHb generation. The rate of PFHb generation scaled inversely with the Cavitation number at a constant flow rate, suggesting that the size of the attached cavity was the dominant hemolytic factor.

Hemolytic and cytotoxic properties of saponin purified from Holothuria leucospilota sea cucumber.

PubMed

Soltani, Mozhgan; Parivar, Kazem; Baharara, Javad; Kerachian, Mohammad Amin; Asili, Javad

2014-10-01

Holothuroids (sea cucumbers) are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota). The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC), hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cells, a human lung cancer cell line. The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR) spectrum of the extract showed hydroxyl (-OH), alkyl (C-H), ether (C-O) and ester (-C=O) absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.

Synergistic Interplay of Medicinal Chemistry and Formulation Strategies in Nanotechnology - From Drug Discovery to Nanocarrier Design and Development.

PubMed

Sunoqrot, Suhair; Hamed, Rania; Abdel-Halim, Heba; Tarawneh, Ola

2017-01-01

Over the last few decades, nanotechnology has given rise to promising new therapies and diagnostic tools for a wide range of diseases, especially cancer. The unique properties of nanocarriers such as liposomes, polymeric nanoparticles, micelles, and bioconjugates have mainly been exploited to enhance drug solubility, dissolution, and bioavailability. The most important advantage offered by nanotechnology is the ability to specifically target organs, tissues, and individual cells, which ultimately reduces the systemic side effects and improves the therapeutic index of drug molecules. The contribution of medicinal chemistry to nanotechnology is evident in the abundance of new active molecules that are being discovered but are faced with tremendous delivery challenges by conventional formulation strategies. Additionally, medicinal chemistry plays a crucial role in all the steps involved in the preparation of nanocarriers, where structure-activity relationships of the drug molecule as well as the nanocarrier are harnessed to enhance the design, efficacy, and safety of nanoformulations. The aim of this review is to provide an overview of the contributions of medicinal chemistry to nanotechnology, from supplying drug candidates and inspiring high-throughput nanocarrier design strategies, to structure-activity relationship elucidation and construction of computational models for better understanding of nanocarrier physicochemical properties and biological behavior. These two fields are undoubtedly interconnected and we will continue to see the fruits of that communion for years to come. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Development of biodegradable hyperbranched core-multishell nanocarriers for efficient topical drug delivery.

PubMed

Du, Fang; Hönzke, Stefan; Neumann, Falko; Keilitz, Juliane; Chen, Wei; Ma, Nan; Hedtrich, Sarah; Haag, Rainer

2016-11-28

The topical application of drugs allows for a local application in skin disease and can reduce side effects. Here we present biodegradable core-multishell (CMS) nanocarriers which are composed of a hyperbranched polyglycerol core functionalized with diblock copolymers consisting of polycaprolactone (PCL) and poly(ethylene glycol) (mPEG) as the outer shell. The anti-inflammatory drug Dexamethasone (Dexa) was loaded into these CMS nanocarriers. DLS results suggested that Dexa loaded nanoparticles mostly act as a unimolecular carrier system. With longer PCL segments, a better transport capacity is observed. In vitro skin permeation studies showed that CMS nanocarriers could improve the Nile red penetration through the skin by up to 7 times, compared to a conventional cream formulation. Interestingly, covalently FITC-labeled CMS nanocarriers remain in the stratum corneum layer. This suggests the enhancement is due to the release of cargo after being transported into the stratum corneum by the CMS nanocarriers. In addition, the hPG-PCL-mPEG CMS nanocarriers exhibited good stability, low cytotoxicity, and their production can easily be scaled up, which makes them promising nanocarriers for topical drug delivery. Copyright © 2016 Elsevier B.V. All rights reserved.

Vascular-targeted nanocarriers: design considerations and strategies for successful treatment of atherosclerosis and other vascular diseases.

PubMed

Kelley, William J; Safari, Hanieh; Lopez-Cazares, Genesis; Eniola-Adefeso, Omolola

2016-11-01

Vascular-targeted nanocarriers are an attractive option for the treatment of a number of cardiovascular diseases, as they allow for more specific delivery and increased efficacy of many small molecule drugs. However, immune clearance, limited cellular uptake, and particle-cell dynamics in blood flow can hinder nanocarrier efficacy in many applications. This review aims to investigate successful strategies for the use of vascular-targeted nanocarriers in the treatment of cardiovascular diseases such as atherosclerosis. In particular, the review will highlight strategies employed for actively targeting the components of the atherosclerotic plaque, including endothelial cells, macrophages, and platelets and passive targeting via endothelial permeability, as well as design specifications (such as size, shape, and density) aimed at enhancing the ability of nanocarriers to reach the vascular wall. WIREs Nanomed Nanobiotechnol 2016, 8:909-926. doi: 10.1002/wnan.1414 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

Comparative study of the hemolytic and cytotoxic activities of nematocyst venoms from the jellyfish Cyanea nozakii Kishinouye and Nemopilema nomurai Kishinouye

NASA Astrophysics Data System (ADS)

Pang, Min; Xu, Jintao; Liu, Yunlong; Zhang, Xuelei

2017-10-01

Two species of jellyfish, Cyanea nozakii Kishinouye and Nemopilema nomurai Kishinouye, have occurred off coastal areas of the northeastern China Sea, Yellow Sea, and Bohai Sea in recent years. They influence marine ecosystem safety and fishery production, and also pose a risk to human health. The current study examined the hemolytic and cytotoxic activities of crude venoms extracted from the nematocysts of C. nozakii and N. nomurai. The results showed that there were more nematocysts on tentacles from C. nozakii than on tentacles of the same length from N. nomurai. The protein concentration per nematocyst extracted from N. nomurai was higher than that from C. nozakii. Both nematocyst venoms showed dose- and time-dependent hemolytic activity on erythrocytes from chicken, pigeon, and sheep, with sheep erythrocytes being the most sensitive, with EC50 values of 69.69 and 63.62 μg/mL over a 30-min exposure with N. nomurai and C. nozakii nematocyst venoms, respectively. A cytotoxic assay of both jellyfish venoms on A431 human epidermal carcinoma cells resulted in IC50 values of 68.6 and 40.9 μg/mL after 24-h incubation, respectively, with venom from C. nozakii showing stronger cytotoxic activity than that from N. nomurai. The results of current study indicate that nematocyst venom from C. nozakii had stronger hemolytic and cytotoxic activities than that from N. nomurai and, thus, C. nozakii might be more harmful to the health of humans and other species than are N. nomurai when they appear in coastal waters.

Assessment of phytochemicals, antioxidant, anti-lipid peroxidation and anti-hemolytic activity of extract and various fractions of Maytenus royleanus leaves.

PubMed

Shabbir, Maria; Khan, Muhammad Rashid; Saeed, Naima

2013-06-22

Maytenus royleanus is traditionally used in gastro-intestinal disorders. The aim of this study was to evaluate the methanol extract of leaves and its derived fractions for various antioxidant assays and for its potential against lipid peroxidation and hemolytic activity. Various parameters including scavenging of free-radicals (DPPH, ABTS, hydroxyl and superoxide radical), hydrogen peroxide scavenging, Fe3+ to Fe2+ reducing capacity, total antioxidant capacity, anti-lipid peroxidation and anti-hemolytic activity were investigated. Methanol extract and its derived fractions were also subjected for chemical constituents. LC-MS was also performed on the methanol extract. Qualitative analysis of methanol extract exhibited the presence of alkaloids, anthraquinones, cardiac glycosides, coumarins, flavonoids, saponins, phlobatannins, tannins and terpenoids. LC-MS chromatogram indicated the composition of diverse compounds including flavonoids, phenolics and phytoestrogens. Methanol extract, its ethyl acetate and n-butanol fractions constituted the highest amount of total phenolic and flavonoid contents and showed a strong correlation coefficient with the IC50 values for the scavenging of DPPH, hydrogen peroxide radicals, superoxide radicals, anti-lipid peroxidation and anti-hemolytic efficacy. Moreover, n-butanol fraction showed the highest scavenging activity for ABTS radicals and for reduction of Fe3+ to Fe2+. Present results suggested the therapeutic potential of Maytenus royleanus leaves, in particular, methanol extract, ethyl acetate and n-butanol fraction as therapeutic agent against free-radical associated damages. The protective potential of the extract and or fraction may be attributed due to the high concentration of phenolic, flavonoid, tannins and terpenoids.

Advances in the use of nanocarriers for cancer diagnosis and treatment

PubMed Central

Vieira, Débora Braga; Gamarra, Lionel Fernel

2016-01-01

ABSTRACT The use of nanocarriers as drug delivery systems for therapeutic or imaging agents can improve the pharmacological properties of commonly used compounds in cancer diagnosis and treatment. Advances in the surface engineering of nanoparticles to accommodate targeting ligands turned nanocarriers attractive candidates for future work involving targeted drug delivery. Although not targeted, several nanocarriers have been approved for clinical use and they are currently used to treat and/or diagnosis various types of cancers. Furthermore, there are several formulations, which are now in various stages of clinical trials. This review examined some approved formulations and discussed the advantages of using nanocarriers in cancer therapy. PMID:27074238

Retinal phlebitis associated with autoimmune hemolytic anemia.

PubMed

Chew, Fiona L M; Tajunisah, Iqbal

2009-01-01

To describe a case of retinal phlebitis associated with autoimmune hemolytic anemia. Observational case report. A 44-year-old Indian man diagnosed with autoimmune hemolytic anemia presented with a 1-week history of blurred vision in both eyes. Fundus biomicroscopy revealed bilateral peripheral retinal venous sheathing and cellophane maculopathy. Fundus fluorescent angiogram showed bilateral late leakage from the peripheral venous arcades and submacular fluid accumulation. The retinal phlebitis resolved following a blood transfusion and administration of systemic steroids. Retinopathy associated with autoimmune hemolytic anemia is not well known. This is thought to be the first documentation of retinal phlebitis occurring in this condition.

Highly lipophilic pluronics-conjugated polyamidoamine dendrimer nanocarriers as potential delivery system for hydrophobic drugs.

PubMed

Nguyen, Thi Tram Chau; Nguyen, Cuu Khoa; Nguyen, Thi Hiep; Tran, Ngoc Quyen

2017-01-01

In the study, four kinds of pluronics (P123, F68, F127 and F108) with varying hydrophilic-lipophilic balance (HLB) values were modified and conjugated on 4th generation of polyamidoamine dendrimer (PAMAM). The obtained results from FT-IR, 1 H NMR and GPC showed that the pluronics effectively conjugated on the dendrimer. The molecular weight of four PAMAM G4.0-Pluronics and its morphologies are in range of 200.15-377.14kDa and around 60-180nm in diameter by TEM, respectively. Loading efficiency and release of hydrophobic fluorouracil (5-FU) anticancer drug were evaluated by HPLC; Interesting that the dendrimer nanocarrier was conjugated with the highly lipophilic pluronic P123 (G4.0-P123) exhibiting a higher drug loading efficiency (up to 76.25%) in comparison with another pluronics. Live/dead fibroblast cell staining assay mentioned that all conjugated nanocarriers are highly biocompatible. The drug-loaded nanocarriers also indicated a highly anti-proliferative activity against MCF-7 breast cancer cell. The obtained results demonstrated a great potential of the highly lipophilic pluronics-conjugated nanocarriers in hydrophobic drugs delivery for biomedical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Biochemical evaluation of the anticancer potential of the polyamine-based nanocarrier Nano11047

PubMed Central

Ferrari, Elena; Xie, Ying; Yu, Fei; Marton, Laurence J.; Oupicky, David; Casero, Robert A.

2017-01-01

Synthesizing polycationic polymers directly from existing drugs overcomes the drug-loading limitations often associated with pharmacologically inert nanocarriers. We recently described nanocarriers formed from a first-generation polyamine analogue, bis(ethyl)norspermine (BENSpm), that could simultaneously target polyamine metabolism while delivering therapeutic nucleic acids. In the current study, we describe the synthesis and evaluation of self-immolative nanocarriers derived from the second-generation polyamine analogue PG-11047. Polyamines are absolutely essential for proliferation and their metabolism is frequently dysregulated in cancer. Through its effects on polyamine metabolism, PG-11047 effectively inhibits tumor growth in cancer cell lines of multiple origins as well as in human tumor mouse xenografts. Promising clinical trials have been completed verifying the safety and tolerance of this rotationally restricted polyamine analogue. We therefore used PG-11047 as the basis for Nano11047, a biodegradable, prodrug nanocarrier capable of targeting polyamine metabolism. Following exposure of lung cancer cell lines to Nano11047, uptake and intracellular degradation into the parent compound PG-11047 was observed. The release of PG-11047 highly induced the polyamine catabolic enzyme activities of spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX). By contrast, the activity of ornithine decarboxylase (ODC), a rate-limiting enzyme in polyamine biosynthesis and a putative oncogene, was decreased. Consequently, intracellular levels of the natural polyamines were depleted concurrent with tumor cell growth inhibition. This availability of Nano11047 as a novel drug form and potential nucleic acid delivery vector will potentially benefit and encourage future clinical studies. PMID:28423064

Biochemical evaluation of the anticancer potential of the polyamine-based nanocarrier Nano11047.

PubMed

Murray-Stewart, Tracy; Ferrari, Elena; Xie, Ying; Yu, Fei; Marton, Laurence J; Oupicky, David; Casero, Robert A

2017-01-01

Synthesizing polycationic polymers directly from existing drugs overcomes the drug-loading limitations often associated with pharmacologically inert nanocarriers. We recently described nanocarriers formed from a first-generation polyamine analogue, bis(ethyl)norspermine (BENSpm), that could simultaneously target polyamine metabolism while delivering therapeutic nucleic acids. In the current study, we describe the synthesis and evaluation of self-immolative nanocarriers derived from the second-generation polyamine analogue PG-11047. Polyamines are absolutely essential for proliferation and their metabolism is frequently dysregulated in cancer. Through its effects on polyamine metabolism, PG-11047 effectively inhibits tumor growth in cancer cell lines of multiple origins as well as in human tumor mouse xenografts. Promising clinical trials have been completed verifying the safety and tolerance of this rotationally restricted polyamine analogue. We therefore used PG-11047 as the basis for Nano11047, a biodegradable, prodrug nanocarrier capable of targeting polyamine metabolism. Following exposure of lung cancer cell lines to Nano11047, uptake and intracellular degradation into the parent compound PG-11047 was observed. The release of PG-11047 highly induced the polyamine catabolic enzyme activities of spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMOX). By contrast, the activity of ornithine decarboxylase (ODC), a rate-limiting enzyme in polyamine biosynthesis and a putative oncogene, was decreased. Consequently, intracellular levels of the natural polyamines were depleted concurrent with tumor cell growth inhibition. This availability of Nano11047 as a novel drug form and potential nucleic acid delivery vector will potentially benefit and encourage future clinical studies.

DNA Dendrimer: An Efficient Nanocarrier of Functional Nucleic Acids for Intracellular Molecular Sensing

PubMed Central

2015-01-01

Functional nucleic acid (FNA)-based sensing systems have been developed for efficient detection of a wide range of biorelated analytes by employing DNAzymes or aptamers as recognition units. However, their intracellular delivery has always been a concern, mainly in delivery efficiency, kinetics, and the amount of delivered FNAs. Here we report a DNA dendrimer scaffold as an efficient nanocarrier to deliver FNAs and to conduct in situ monitoring of biological molecules in living cells. A histidine-dependent DNAzyme and an anti-ATP aptamer were chosen separately as the model FNAs to make the FNA dendrimer. The FNA-embedded DNA dendrimers maintained the catalytic activity of the DNAzyme or the aptamer recognition function toward ATP in the cellular environment, with no change in sensitivity or specificity. Moreover, these DNA dendrimeric nanocarriers show excellent biocompatibility, high intracellular delivery efficiency, and sufficient stability in a cellular environment. This FNA dendrimeric nanocarrier may find a broad spectrum of applications in biomedical diagnosis and therapy. PMID:24806614

Hemolytic-uremic syndrome

MedlinePlus

... page, please enable JavaScript. Shiga-like toxin producing E coli hemolytic-uremic syndrome (STEC-HUS) is a disorder ... HUS) often occurs after a gastrointestinal infection with E coli bacteria ( Escherichia coli O157:H7). However, the condition ...

Hemolytic and cytotoxic properties of saponin purified from Holothuria leucospilota sea cucumber

PubMed Central

Soltani, Mozhgan; Parivar, Kazem; Baharara, Javad; Kerachian, Mohammad Amin; Asili, Javad

2014-01-01

Background: Holothuroids (sea cucumbers) are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota). The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. Methods: The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC), hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cells, a human lung cancer cell line. Results: The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR) spectrum of the extract showed hydroxyl (-OH), alkyl (C-H), ether (C-O) and ester (–C=O) absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. Conclusion: The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate. PMID:26989736

Hydrodynamic interactions for complex-shaped nanocarriers in targeted drug delivery

NASA Astrophysics Data System (ADS)

Wang, Yaohong; Eckmann, David; Radhakrishnan, Ravi; Ayyaswamy, Portonovo

2014-11-01

Nanocarrier motion in a blood vessel involves hydrodynamic and Brownian interactions, which collectively dictate the efficacy in targeted drug delivery. The shape of nanocarriers plays a crucial role in drug delivery. In order to quantify the flow and association properties of elliptical nanoparticles, we have developed an arbitrary Lagrangian-Eulerian framework with capabilities to simulate the hydrodynamic motion of nanoparticles of arbitrary shapes. We introduce the quaternions for rotational motion, and two collision models, namely, (a) an impulse-based model for wall-particle collision, and (b) the short-range repulsive Gay-Berne potential for particle-particle collision. We also study the red blood cell and nanocarrier (such as ellipsoid) interactions. We compare our results with those obtained for a hard sphere model for both RBCs and nanocarriers. Supported by NIH through grant U01-EB016027.

Comparative Study of Esterase and Hemolytic Activities in Clinically Important Candida Species, Isolated From Oral Cavity of Diabetic and Non-diabetic Individuals.

PubMed

Fatahinia, Mahnaz; Poormohamadi, Farzad; Zarei Mahmoudabadi, Ali

2015-03-01

Diabetes mellitus as a chronic metabolic disease occurs in patients with partial or complete deficiency of insulin secretion or disorder in action of insulin on tissue. The disease is known to provide conditions for overgrowth of Candida species. Candida spp. cause candidiasis by many virulence factors such as esterase, hemolysin and phospholipase. This study aimed to compare esterase and hemolytic activity in various Candida species isolated from oral cavity of diabetic and non-diabetic individuals. Swab samples were taken from 95 patients with diabetes (35 men and 60 women) and 95 normal persons (42 men and 53 women) and cultured on Sabouraud dextrose agar. Identification of isolated yeasts was performed by germ tube test, morphology on CHROMagar Candida medium, corn meal agar and ability to grow at 45°C. Hemolysin activity was evaluated using blood plate assay and esterase activity was determined using the Tween 80 opacity test. Different Candida species were isolated from 57 (60%) diabetic and 24 (25%) non-diabetic individuals. Esterase activity was detected in all Candida isolates. Only 21.6% of C. albicans from patients with diabetes had esterase activity as + 3, while it ranged from + 1 to + 2 in others. Hemolytic activity was determined in C. albicans, C. dubliniensis, C. glabrata and C. krusei as 0.79, 0.58, 0.66 and 0.74, respectively. Hemolytic activity was significantly different in the two groups of diabetics and non-diabetics. Oral carriage of C. albicans in the diabetic group (n = 42; 66.7%) was significantly greater than the control group (n = 16; 57.1%). Esterase activity of C. albicans in diabetic group was higher than non-diabetic group. Although C. albicans remains the most frequently pathogenic yeast for human, but other species are increasing.

Novel alginate-based nanocarriers as a strategy to include high concentrations of hydrophobic compounds in hydrogels for topical application.

PubMed

Nguyen, H T P; Munnier, E; Souce, M; Perse, X; David, S; Bonnier, F; Vial, F; Yvergnaux, F; Perrier, T; Cohen-Jonathan, S; Chourpa, I

2015-01-26

The cutaneous penetration of hydrophobic active molecules is of foremost concern in the dermatology and cosmetic formulation fields. The poor solubility in water of those molecules limits their use in hydrophilic forms such as gels, which are favored by patients with chronic skin disease. The aim of this work is to design a novel nanocarrier of hydrophobic active molecules and to determine its potential as an ingredient of a topical form. The nanocarrier consists of an oily core surrounded by a protective shell of alginate, a natural polysaccharide isolated from brown algae. These calcium alginate-based nanocarriers (CaANCs) were prepared at room temperature and without the use of organic solvent by an accelerated nanoemulsification-polymer crosslinking method. The size (hydrodynamic diameter ~200 nm) and surface charge (zeta potential ~ - 30 mV) of the CaANCs are both compatible with their application on skin. CaANCs loaded with a fluorescent label were stable in model hydrophilic galenic forms under different storage conditions. Curcumin was encapsulated in CaANCs with an efficiency of ~95%, fully retaining its antioxidant activity. The application of the curcumin-loaded CaANCs on excised human skin led to a significant accumulation of the active molecules in the upper layers of the skin, asserting the potential of these nanocarriers in active pharmaceutical and cosmetic ingredients topical delivery.

Novel alginate-based nanocarriers as a strategy to include high concentrations of hydrophobic compounds in hydrogels for topical application

NASA Astrophysics Data System (ADS)

Nguyen, H. T. P.; Munnier, E.; Souce, M.; Perse, X.; David, S.; Bonnier, F.; Vial, F.; Yvergnaux, F.; Perrier, T.; Cohen-Jonathan, S.; Chourpa, I.

2015-06-01

The cutaneous penetration of hydrophobic active molecules is of foremost concern in the dermatology and cosmetic formulation fields. The poor solubility in water of those molecules limits their use in hydrophilic forms such as gels, which are favored by patients with chronic skin disease. The aim of this work is to design a novel nanocarrier of hydrophobic active molecules and to determine its potential as an ingredient of a topical form. The nanocarrier consists of an oily core surrounded by a protective shell of alginate, a natural polysaccharide isolated from brown algae. These calcium alginate-based nanocarriers (CaANCs) were prepared at room temperature and without the use of organic solvent by an accelerated nanoemulsification-polymer crosslinking method. The size (hydrodynamic diameter ˜200 nm) and surface charge (zeta potential ˜ - 30 mV) of the CaANCs are both compatible with their application on skin. CaANCs loaded with a fluorescent label were stable in model hydrophilic galenic forms under different storage conditions. Curcumin was encapsulated in CaANCs with an efficiency of ˜95%, fully retaining its antioxidant activity. The application of the curcumin-loaded CaANCs on excised human skin led to a significant accumulation of the active molecules in the upper layers of the skin, asserting the potential of these nanocarriers in active pharmaceutical and cosmetic ingredients topical delivery.

[Treatment and results of therapy in autoimmune hemolytic anemia].

PubMed

Tasić, J; Macukanović, L; Pavlović, M; Koraćević, S; Govedarević, N; Kitić, Lj; Tijanić, I; Bakić, M

1994-01-01

Basic principles in the therapy of idiopathic autoimmune hemolytic anemia induced by warm antibody were glucocorticoides and splenectomy. Immunosupresive drugs, plasmaferesis and intravenous high doses gamma globulin therapy are also useful. In secundary autoimmune hemolytic anemia induced by warm antibody we treated basic illness. During the period of 1990-1992 we treated 21 patients with primary autoimmune hemolytic anemia and 6 patients with secondary /4 CLL and 2 Non-Hodgkin's lymphoma/. Complete remission we found as a normalisation of reticulocites and hemoglobin level respectively. Complete remission by corticoides we got in 14/21 patients, partial response in 2/21 respectively. Complete response by splenectomy we got in 2/3 splenoctomized patients (idiopathic type). For successful treatment secondary hemolytic anemias we treated primary diseases (CLL and malignant lymphoma) and we got in 4/6 patients complete remission. Our results were standard in both type of autoimmune hemolytic anaemias induced by warm antibody.

Liposomal nanocarriers for tumor imaging.

PubMed

Erdogan, Suna

2009-04-01

Currently used imaging modalities such as scintigraphy, computed tomography, magnetic resonance imaging and ultrasonography require the sufficient intensity of a corresponding signal from an area of interest to differentiate this area from the surrounding tissues. Targeting of various reporter moieties directly to the specific organs, tissues or tumors provide the highest dose of drug directly where it is needed. Many different types of nanoparticles are currently being studied for applications in nanomedicine. Among particulate drug carriers, liposomes are one of the most extensively studied and possess the most suitable characteristics for encapsulation of many drugs, genes, and diagnostic (imaging) agents. Among the many potential targets for such nanocarriers, tumors have been most often investigated. This review attempts to summarize the currently available information regarding liposomal nanocarriers for cancer imaging.

Late onset seizures, hemiparesis and blindness in hemolytic uremic syndrome.

PubMed

Bennett, B; Booth, T; Quan, A

2003-03-01

Neurologic complications of hemolytic uremic syndrome, including seizures, usually occur early during the acute phase of the illness. We report a3-year-old girl with classic diarrhea-associated hemolytic uremic syndrome who developed late onset seizures, hemiparesis and transient blindness on the 17th hospital day, at which time her recovery was characterized by improvement in her blood pressure, serum electrolytes, renal function, hematocrit and platelet count. A CT and MR revealed brainstem and posterior parietal and occipital infarct/edema. The association of these radiologic findings within the posterior distribution along with visual loss and seizures are unique to posterior reversible encephalopathy syndrome. Within 7 days, she regained motor function and vision and had no further seizure activity. At 6 months follow-up, physical examination revealed normal motor function and vision and a repeat MR showed near resolution of the previous findings with minimal occipital lobe gliosis. This case report describes the uncommon finding of late onset seizures occurring during the recovery phase of hemolytic uremic syndrome with MR findings consistent with posterior reversible encephalopathy syndrome.

Assessment of hemolytic activity, enzyme production and bacteriocin characterization of Bacillus subtilis LR1 isolated from the gastrointestinal tract of fish.

PubMed

Banerjee, Goutam; Nandi, Ankita; Ray, Arun Kumar

2017-01-01

In the present investigation, probiotic potential (antagonistic activity, enzyme production, hemolytic activity, biosafety, antibiotic sensitivity and bile tolerance level) of Bacillus subtilis LR1 was evaluated. Bacteriocin produced by the bacterial strain B. subtilis LR1 isolated from the gastrointestinal tract of Labeo rohita was purified and characterized. The molecular weight of the purified bacteriocin was ~50 kDa in 12 % Native PAGE and showed inhibitory activity against four fish pathogens such as Bacillus mycoides, Aeromonas salmonicida, Pseudomonas fluorescens and Aeromonas hydrophila. The purified bacteriocin was maximally active at temperature 40 °C and pH 7.0, while none of the tested surfactants affect the bacteriocin activity. Extracellular enzyme activity of the selected bacterial strain was also evaluated. Amylase activity was estimated to be highest (38.23 ± 1.15 µg of maltose liberated mg -1  protein ml -1 of culture filtrate) followed by cellulase and protease activity. The selected bacterium was sensitive to most of the antibiotics used in this experiment, can tolerate 0.25 % bile salt and non-hemolytic in nature. Finally, the efficiency of the proposed probiotic candidate was evaluated in in vivo condition. It was detected that the bacterial strain can effectively reduce bacterial pathogenicity in Indian major carps.

Transformable DNA Nanocarriers for Plasma Membrane Targeted Delivery of Cytokine

PubMed Central

Sun, Wujin; Ji, Wenyan; Hu, Quanyin; Yu, Jicheng; Wang, Chao; Qian, Chenggen; Hochu, Gabrielle; Gu, Zhen

2016-01-01

Direct delivery of cytokines using nanocarriers holds great promise for cancer therapy. However, the nanometric scale of the vehicles made them susceptible to size-dependent endocytosis, reducing the plasma membrane-associated apoptosis signalling. Herein, we report a tumor microenvironment-responsive and transformable nanocarrier for cell membrane targeted delivery of cytokine. This formulation is comprised of a phospholipase A2 (PLA2) degradable liposome as a shell, and complementary DNA nanostructures (designated as nanoclews) decorated with cytokines as the cores. Utilizing the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a model cytokine, we demonstrate that the TRAIL loaded DNA nanoclews are capable of transforming into nanofibers after PLA2 activation. The nanofibers with micro-scaled lengths efficiently present the loaded TRAIL to death receptors on the cancer cell membrane and amplified the apoptotic signalling with reduced TRAIL internalization. PMID:27131597

Significance of Hemolytic Colonies in Throat Cultures

PubMed Central

Quinn, Robert W.; Lowry, P. Nye

1969-01-01

These studies indicate that a single strain of hemolytic streptococci almost exclusively predominates the bacterial flora in patients with streptococcal infections and in the carrier state. One can proceed with confidence that, in isolating streptococci from throat swabs cultured on blood-agar plates, only a single hemolytic colony need be picked for serological grouping and typing. PMID:4888863

Multifunctional High Drug Loading Nanocarriers for Cancer Drug Delivery

NASA Astrophysics Data System (ADS)

Jin, Erlei

2011-12-01

Most anticancer drugs have poor water-solubility, rapid blood clearance, low tumor-selectivity and severe systemic toxicity to healthy tissues. Thus, polymeric nanocarriers have been widely explored for anticancer drugs to solve these problems. However, polymer nanocarriers developed to date still suffer drawbacks including low drug loading contents, premature drug release, slow cellular internalization, slow intracellular drug release and thereby low therapeutic efficiency in cancer thermotherapy. Accordingly, in this dissertation, functional nanocapsules and nanoparticles including high drug loading liposome-like nanocapsules, high drug loading phospholipid-mimic nanocapsules with fast intracellular drug release, high drug loading charge-reversal nanocapsules, TAT based long blood circulation nanoparticles and charge-reversal nuclear targeted nanoparticles are designed and synthesized. These functional carriers have advantages such as high drug loading contents without premature drug release, fast cellular internalization and intracellular drug release, nuclear targeted delivery and long blood circulation. As a result, all these drug carriers show much higher in vitro and in vivo anti-cancer activities.

MRI mediated, non-invasive tracking of intratumoral distribution of nanocarriers in rat glioma

NASA Astrophysics Data System (ADS)

Karathanasis, Efstathios; Park, Jaekeun; Agarwal, Abhiruchi; Patel, Vijal; Zhao, Fuqiang; Annapragada, Ananth V.; Hu, Xiaoping; Bellamkonda, Ravi V.

2008-08-01

Nanocarrier mediated therapy of gliomas has shown promise. The success of systemic nanocarrier-based chemotherapy is critically dependent on the so-called leaky vasculature to permit drug extravasation across the blood-brain barrier. Yet, the extent of vascular permeability in individual tumors varies widely, resulting in a correspondingly wide range of responses to the therapy. However, there exist no tools currently for rationally determining whether tumor blood vessels are amenable to nanocarrier mediated therapy in an individualized, patient specific manner today. To address this need for brain tumor therapy, we have developed a multifunctional 100 nm scale liposomal agent encapsulating a gadolinium-based contrast agent for contrast-enhanced magnetic resonance imaging with prolonged blood circulation. Using a 9.4 T MRI system, we were able to track the intratumoral distribution of the gadolinium-loaded nanocarrier in a rat glioma model for a period of three days due to improved magnetic properties of the contrast agent being packaged in a nanocarrier. Such a nanocarrier provides a tool for non-invasively assessing the suitability of tumors for nanocarrier mediated therapy and then optimizing the treatment protocol for each individual tumor. Additionally, the ability to image the tumor in high resolution can potentially constitute a surgical planning tool for tumor resection.

MRI mediated, non-invasive tracking of intratumoral distribution of nanocarriers in rat glioma.

PubMed

Karathanasis, Efstathios; Park, Jaekeun; Agarwal, Abhiruchi; Patel, Vijal; Zhao, Fuqiang; Annapragada, Ananth V; Hu, Xiaoping; Bellamkonda, Ravi V

2008-08-06

Nanocarrier mediated therapy of gliomas has shown promise. The success of systemic nanocarrier-based chemotherapy is critically dependent on the so-called leaky vasculature to permit drug extravasation across the blood-brain barrier. Yet, the extent of vascular permeability in individual tumors varies widely, resulting in a correspondingly wide range of responses to the therapy. However, there exist no tools currently for rationally determining whether tumor blood vessels are amenable to nanocarrier mediated therapy in an individualized, patient specific manner today. To address this need for brain tumor therapy, we have developed a multifunctional 100 nm scale liposomal agent encapsulating a gadolinium-based contrast agent for contrast-enhanced magnetic resonance imaging with prolonged blood circulation. Using a 9.4 T MRI system, we were able to track the intratumoral distribution of the gadolinium-loaded nanocarrier in a rat glioma model for a period of three days due to improved magnetic properties of the contrast agent being packaged in a nanocarrier. Such a nanocarrier provides a tool for non-invasively assessing the suitability of tumors for nanocarrier mediated therapy and then optimizing the treatment protocol for each individual tumor. Additionally, the ability to image the tumor in high resolution can potentially constitute a surgical planning tool for tumor resection.

Chirality-dependent cellular uptake of chiral nanocarriers and intracellular delivery of different amounts of guest molecules

NASA Astrophysics Data System (ADS)

Kehr, Nermin Seda; Jose, Joachim

2017-12-01

We demonstrate the organic molecules loaded and chiral polymers coated periodic mesoporous organosilica (PMO) to generate chiral nanocarriers that we used to study chirality-dependent cellular uptake in serum and serum-free media and the subsequent delivery of different amounts of organic molecules into cells. Our results show that the amount of internalized PMO and thus the transported amount of organic molecules by nanocarrier PMO into cells was chirality dependent and controlled by hard/soft protein corona formation on the PMO surfaces. Therefore, this study demonstrate that chiral porous nanocarriers could potentially be used as advanced drug delivery systems which are able to use the specific chiral surface-protein interactions to influence/control the amount of (bio)active molecules delivered to cells in drug delivery and/or imaging applications.

Group A β-hemolytic streptococcal pharyngotonsillitis outbreak.

PubMed

Culqui, Dante R; Manzanares-Laya, Sandra; Van Der Sluis, Sarah Lafuente; Fanlo, Albert Anton; Comas, Rosa Bartolomé; Rossi, Marcello; Caylá, Joán A

2014-04-01

The aim was to describe an outbreak of group A β-hemolytic streptococcal pharyngotonsillitis in health care professionals. This is a cross-sectional descriptive study of 17 clients who dined at the same table in a restaurant in Barcelona in July 2012. The frequency, timing and severity of symptoms were analyzed, as were demographic variables and others concerning the food ingested. The attack rate was 58.8%. Six of the 10 clients were positive for group A β-hemolytic streptococcal. Six of the 13 individuals who handled the food involved in the dinner had symptoms. No association was identified with the food consumed. There is epidemiological evidence of foodborne group A β-hemolytic streptococcal transmission, but respiratory transmission could not be ruled out.

Group A β-hemolytic streptococcal pharyngotonsillitis outbreak

PubMed Central

Culqui, Dante R; Manzanares-Laya, Sandra; Van Der Sluis, Sarah Lafuente; Fanlo, Albert Anton; Comas, Rosa Bartolomé; Rossi, Marcello; Caylá, Joán A

2014-01-01

The aim was to describe an outbreak of group A β-hemolytic streptococcal pharyngotonsillitis in health care professionals. This is a cross-sectional descriptive study of 17 clients who dined at the same table in a restaurant in Barcelona in July 2012. The frequency, timing and severity of symptoms were analyzed, as were demographic variables and others concerning the food ingested. The attack rate was 58.8%. Six of the 10 clients were positive for group A β-hemolytic streptococcal. Six of the 13 individuals who handled the food involved in the dinner had symptoms. No association was identified with the food consumed. There is epidemiological evidence of foodborne group A β-hemolytic streptococcal transmission, but respiratory transmission could not be ruled out. PMID:24897054

Multi-scale Observation of Biological Interactions of Nanocarriers: from Nano to Macro

PubMed Central

Jin, Su-Eon; Bae, Jin Woo; Hong, Seungpyo

2010-01-01

Microscopic observations have played a key role in recent advancements in nanotechnology-based biomedical sciences. In particular, multi-scale observation is necessary to fully understand the nano-bio interfaces where a large amount of unprecedented phenomena have been reported. This review describes how to address the physicochemical and biological interactions of nanocarriers within the biological environments using microscopic tools. The imaging techniques are categorized based on the size scale of detection. For observation of the nano-scale biological interactions of nanocarriers, we discuss atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). For the micro to macro-scale (in vitro and in vivo) observation, we focus on confocal laser scanning microscopy (CLSM) as well as in vivo imaging systems such as magnetic resonance imaging (MRI), superconducting quantum interference devices (SQUIDs), and IVIS®. Additionally, recently developed combined techniques such as AFM-CLSM, correlative Light and Electron Microscopy (CLEM), and SEM-spectroscopy are also discussed. In this review, we describe how each technique helps elucidate certain physicochemical and biological activities of nanocarriers such as dendrimers, polymers, liposomes, and polymeric/inorganic nanoparticles, thus providing a toolbox for bioengineers, pharmaceutical scientists, biologists, and research clinicians. PMID:20232368

Bioconjugation of recombinant tissue plasminogen activator to magnetic nanocarriers for targeted thrombolysis

PubMed Central

Yang, Hung-Wei; Hua, Mu-Yi; Lin, Kun-Ju; Wey, Shiaw-Pyng; Tsai, Rung-Ywan; Wu, Siao-Yun; Lu, Yi-Ching; Liu, Hao-Li; Wu, Tony; Ma, Yunn-Hwa

2012-01-01

Low-toxicity magnetic nanocarriers (MNCs) composed of a shell of poly [aniline-co-N-(1-one-butyric acid) aniline] over a Fe3O4 magnetic nanoparticle core were developed to carry recombinant tissue plasminogen activator (rtPA) in MNC-rtPA for targeted thrombolysis. With an average diameter of 14.8 nm, the MNCs exerted superparamagnetic properties. Up to 276 μg of active rtPA was immobilized per mg of MNCs, and the stability of the immobilized rtPA was greatly improved during storage at 4°C and 25°C. In vitro thrombolysis testing with a tubing system demonstrated that magnet-guided MNC-rtPA showed significantly improved thrombolysis compared with free rtPA and reduced the clot lysis time from 39.2 ± 3.2 minutes to 10.8 ± 4.2 minutes. In addition, magnet-guided MNC-rtPA at 20% of the regular rtPA dose restored blood flow within 15–25 minutes of treatment in a rat embolism model without triggering hematological toxicity. In conclusion, this improved system is based on magnetic targeting accelerated thrombolysis and is potentially amenable to therapeutic applications in thromboembolic diseases. PMID:23055728

Effective use of nanocarriers as drug delivery systems for the treatment of selected tumors

PubMed Central

Ullah, Izhar; Qureshi, Omer Salman; Mustapha, Omer; Shafique, Shumaila; Zeb, Alam

2017-01-01

Nanotechnology has recently gained increased attention for its capability to effectively diagnose and treat various tumors. Nanocarriers have been used to circumvent the problems associated with conventional antitumor drug delivery systems, including their nonspecificity, severe side effects, burst release and damaging the normal cells. Nanocarriers improve the bioavailability and therapeutic efficiency of antitumor drugs, while providing preferential accumulation at the target site. A number of nanocarriers have been developed; however, only a few of them are clinically approved for the delivery of antitumor drugs for their intended actions at the targeted sites. The present review is divided into three main parts: first part presents introduction of various nanocarriers and their relevance in the delivery of anticancer drugs, second part encompasses targeting mechanisms and surface functionalization on nanocarriers and third part covers the description of selected tumors, including breast, lungs, colorectal and pancreatic tumors, and applications of relative nanocarriers in these tumors. This review increases the understanding of tumor treatment with the promising use of nanotechnology. PMID:29042776

Recent Developments of Liposomes as Nanocarriers for Theranostic Applications

PubMed Central

Xing, Hang; Hwang, Kevin; Lu, Yi

2016-01-01

Liposomes are nanocarriers comprised of lipid bilayers encapsulating an aqueous core. The ability of liposomes to encapsulate a wide variety of diagnostic and therapeutic agents has led to significant interest in utilizing liposomes as nanocarriers for theranostic applications. In this review, we highlight recent progress in developing liposomes as nanocarriers for a) diagnostic applications to detect proteins, DNA, and small molecule targets using fluorescence, magnetic resonance, ultrasound, and nuclear imaging; b) therapeutic applications based on small molecule-based therapy, gene therapy and immunotherapy; and c) theranostic applications for simultaneous detection and treatment of heavy metal toxicity and cancers. In addition, we summarize recent studies towards understanding of interactions between liposomes and biological components. Finally, perspectives on future directions in advancing the field for clinical translations are also discussed. PMID:27375783

Nanocarriers in therapy of infectious and inflammatory diseases

NASA Astrophysics Data System (ADS)

Ikoba, Ufuoma; Peng, Haisheng; Li, Haichun; Miller, Cathy; Yu, Chenxu; Wang, Qun

2015-02-01

Nanotechnology is a growing science that has applications in various areas of medicine. The composition of nanocarriers for drug delivery is critical to guarantee high therapeutic performance when targeting specific host sites. Applications of nanotechnology are prevalent in the diagnosis and treatment of infectious and inflammatory diseases. This review summarizes recent advancements in the application of nanotechnology to the therapy of infectious and inflammatory diseases. The major focus is on the design and fabrication of various nanomaterials, characteristics and physicochemical properties of drug-loaded nanocarriers, and the use of these nanoscale drug delivery systems in treating infectious and inflammatory diseases, such as AIDS, hepatitis, tuberculosis, melanoma, and representative inflammatory diseases. Clinical trials and future perspective of the use of nanocarriers are also discussed in detail. We hope that such a review will be valuable to researchers who are exploring nanoscale drug delivery systems for the treatment of specific infectious and inflammatory diseases.

Scalable and cleavable polysaccharide nanocarriers for the delivery of chemotherapy drugs.

PubMed

Wang, Hao; Dai, Tingting; Li, Shengli; Zhou, Shuyan; Yuan, Xiaojing; You, Jiayi; Wang, Chenglong; Mukwaya, Vincent; Zhou, Guangdong; Liu, Guojun; Wei, Xiaohui; Dou, Hongjing

2018-05-01

While polysaccharide-based nanocarriers have been recognized for their crucial roles in tumor theranostics, the industrial-scale production of nanotherapeutics still remains a significant challenge. Most current approaches adopt a postpolymerization self-assembly strategy that follows a separate synthetic step and thus suffers from subgram scale yields and a limited range of application. In this study, we demonstrate the kilogram-scale formation of polysaccharide-polyacrylate nanocarriers at concentrations of up to 5 wt% through a one-pot approach - starting from various acrylate monomers and polysaccharides - that combines aspects of hydrophobicity-induced self-assembly with the free radical graft copolymerization of acrylate monomers from polysaccharide backbones into a single process that is thus denoted as a graft copolymerization induced self-assembly. We also demonstrate that this novel approach is applicable to a broad range of polysaccharides and acrylates. Notably, by choosing a crosslinker that bears a disulfide group and two vinyl capping groups to structurally lock the nanocarriers, the products are rendered cleavable in the reducing environments encountered at tumor sites and thus provide ideal candidates for the construction of anticancer nanotherapeutic systems. In vitro and in vivo studies demonstrated that the use of this nanocarrier for the delivery of doxorubicin hydrochloride (DOX) significantly decreased the side effects of DOX and improved the bio-safety of the chemotherapy accordingly. While polysaccharide-based nanocarriers have been recognized for their crucial roles in tumor theranostics, the industrial-scale production of these nanotherapeutics still remains a significant challenge. Most current approaches adopt a post-polymerization self-assembly strategy which that follows a separate synthetic step, and thus suffers from sub-gram scale yields and a limited range of application. In this study, the hydrophobic effect was combined with

Pure and zinc doped nano-hydroxyapatite: Synthesis, characterization, antimicrobial and hemolytic studies

NASA Astrophysics Data System (ADS)

Tank, Kashmira P.; Chudasama, Kiran S.; Thaker, Vrinda S.; Joshi, Mihir J.

2014-09-01

The structural, antimicrobial, and hemolytic properties and bioactivity have been studied of pure hydroxyapatite (HAP) and zinc doped hydroxyapatite (Zn-HAP) nano-particles for their medical applications. Pure HAP and Zn-HAP nano-particles were synthesized by the surfactant mediated approach. The doping of zinc was estimated by EDAX. The average particle size was determined by applying Scherrer's formula to powdered XRD patterns. The nano-particle morphology was studied by TEM and the presence of various functional groups was identified by FTIR spectroscopy. Good antimicrobial activity of nano-HAP and nano-Zn-HAP was found against five organisms, viz., Pseudomonas aeruginosa and Shigella flexneri as Gram negative as well as Micrococcus luteus, Staphylococcous aureus and Bacillus cereus as Gram positive. The ability of new apatite formation on the surface of pure and doped HAP samples was studied by using Simulated Body Fluid (SBF) in vitro. Hemolytic study indicated that all samples were non-hemolytic and suggesting potential application as bone implant material.

Polysaccharide-based micro/nanocarriers for oral colon-targeted drug delivery.

PubMed

Zhang, Lin; Sang, Yuan; Feng, Jing; Li, Zhaoming; Zhao, Aili

2016-08-01

Oral colon-targeted drug delivery has attracted many researchers because of its distinct advantages of increasing the bioavailability of the drug at the target site and reducing the side effects. Polysaccharides that are precisely activated by the physiological environment of the colon hold greater promise for colon targeting. Considerable research efforts have been directed towards developing polysaccharide-based micro/nanocarriers. Types of polysaccharides for colon targeting and in vitro/in vivo assessments of polysaccharide-based carriers for oral colon-targeted drug delivery are summarised. Polysaccharide-based microspheres have gained increased importance not just for the delivery of the drugs for the treatment of local diseases associated with the colon (colon cancer, inflammatory bowel disease (IBD), amoebiasis and irritable bowel syndrome (IBS)), but also for it's potential for the delivery of anti-rheumatoid arthritis and anti-chronic stable angina drugs. Besides, Polysaccharide-based micro/nanocarriers such as microbeads, microcapsules, microparticles, nanoparticles, nanogels and nanospheres are also introduced in this review.

Exosomes as nanocarriers for immunotherapy of cancer and inflammatory diseases.

PubMed

Tran, Thanh-Huyen; Mattheolabakis, George; Aldawsari, Hibah; Amiji, Mansoor

2015-09-01

Cell secreted exosomes (30-100nm vesicles) play a major role in intercellular communication due to their ability to transfer proteins and nucleic acids from one cell to another. Depending on the originating cell type and the cargo, exosomes can have immunosuppressive or immunostimulatory effects, which have potential application as immunotherapies for cancer and autoimmune diseases. Cellular components shed from tumor cells or antigen presenting cells (APCs), such as dendritic cells, macrophages and B cells, have been shown to be efficiently packaged in exosomes. In this review, we focus on the application of exosomes as nanocarriers and immunological agents for cancer and autoimmune immunotherapy. APC-derived exosomes demonstrate effective therapeutic efficacy for the treatment of cancer and experimental autoimmune diseases such as rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis. In addition to their intrinsic immunomodulating activity, exosomes have many advantages over conventional nanocarriers for drug and gene delivery. Copyright © 2015 Elsevier Inc. All rights reserved.

Albumin based versatile multifunctional nanocarriers for cancer therapy: Fabrication, surface modification, multimodal therapeutics and imaging approaches.

PubMed

Kudarha, Ritu R; Sawant, Krutika K

2017-12-01

Albumin is a versatile protein used as a carrier system for cancer therapeutics. As a carrier it can provide tumor specificity, reduce drug related toxicity, maintain therapeutic concentration of the active moiety like drug, gene, peptide, protein etc. for long period of time and also reduce drug related toxicities. Apart from cancer therapy, it is also utilized in the imaging and multimodal therapy of cancer. This review highlights the important properties, structure and types of albumin based nanocarriers with regards to their use for cancer targeting. It also provides brief discussion on methods of preparation of these nanocarriers and their surface modification. Applications of albumin nanocarriers for cancer therapy, gene delivery, imaging, phototherapy and multimodal therapy have also been discussed. This review also provides brief discussion about albumin based marketed nano formulations and those under clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

Nanocarriers for delivery of siRNA and co-delivery of siRNA and other therapeutic agents.

PubMed

Zhao, Jing; Feng, Si-Shen

2015-07-01

A major problem in cancer treatment is the multidrug resistance. siRNA inhibitors have great advantages to solve the problem, if the bottleneck of their delivery could be well addressed by the various nanocarriers. Moreover, co-delivery of siRNA together with the various anticancer agents in one nanocarrier may maximize their additive or synergistic effect. This review provides a comprehensive summary on the state-of-the-art of the nanocarriers, which may include prodrugs, micelles, liposomes, dendrimers, nanohydrogels, solid lipid nanoparticles, nanoparticles of biodegradable polymers and nucleic acid nanocarriers for delivery of siRNA and co-delivery of siRNA together with anticancer agents with focus on synthesis of the nanocarrier materials, design and characterization, in vitro and in vivo evaluation, and prospect and challenges of nanocarriers.

Nanocarriers for the Effective Treatment of Cervical Cancer: Research Advancements and Patent Analysis.

PubMed

Akhtar, Nida; Pathak, Kamla

2018-04-02

Cervical cancer being the cancer of cervix is caused by the aberrant cell growth that acquires an ability to spread/ invade to other body parts as well. It has been reported to be the second most commonest cause of death and cancer as well among women. Based on the severity of the disease, treatment aspect needs to be explored more in order to overcome the limitations acquired by conventional treatment. Recently, nanocarriers based drug delivery systems including liposomes, nanofibres, metallic NPs, polymeric NPs, dendrimers, polymeric micelles, antibody-drug conjugates etc. have been explored to target and treat cervical cancer. This review highlights numerous recent research and patent reports as well on nanocarriers based systems. Patents viz US, EP and WIPO have been retrieved using sites www.uspto.gov/patft and www.freepatentsonline.com to collect literature on nanocarriers. Various research reports and patents revealed nanocarriers to be effective in treating cervical cancer and these carriers are observed to be safer than the conventional treatment. Nanocarriers results in transforming drug distribution that can overpower drug resistance. Further, nanocarriers based drug delivery systems can particularly target drugs to cellular, subcellular and tissue sites. By enhancing the drug's bioavailability at the desired site, these systems result in therapeutic benefits like enhanced safety and efficacy. Also, in combination with other treatment approaches like radiation, photothermal and gene therapy, nanocarriers are reported to be quite effective and can define novel strategies to combat cervical cancer. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Accelerated blood clearance phenomenon upon cross-administration of PEGylated nanocarriers in beagle dogs

PubMed Central

Wang, Chunling; Cheng, Xiaobo; Su, Yuqing; Pei, Ying; Song, Yanzhi; Jiao, Jiao; Huang, Zhenjun; Ma, Yanfei; Dong, Yinming; Yao, Ying; Fan, Jingjing; Ta, Han; Liu, Xinrong; Xu, Hui; Deng, Yihui

2015-01-01

The cross-administration of nanocarriers modified by poly(ethylene glycol) (PEG), named PEGylated nanocarriers, a type of combination therapy, is becoming an increasingly important method of long-term drug delivery, to decrease side effects, avoid multidrug resistance, and increase therapeutic efficacy. However, repeated injections of PEGylated nanocarriers induces the accelerated blood clearance (ABC) phenomenon, prevents long circulation, and can cause adverse effects owing to alterations in the biodistribution of the drug. Although the nature of the ABC phenomenon that is induced by repeated injections of PEGylated nanocarriers has already been studied in detail, there are few reports on the immune response elicited by the cross-administration of PEGylated nanocarriers. In this study, we investigated the ABC phenomenon induced by the intravenous cross-administration of various PEGylated nanocarriers, including PEGylated liposomes (PL), PEG micelles (PM), PEGylated solid lipid nanoparticles (PSLN), and PEGylated emulsions (PE), in beagle dogs. The results indicated that the magnitude of the immune response elicited by the cross-administration was in the following order (from the strongest to the weakest): PL, PE, PSLN, PM. It is specifically PEG in the brush structure that elicits a significant immune response, in both the induction phase and the effectuation phase. Furthermore, the present study suggests that there is a considerable difference between the effect of repeated injections and cross-administration, depending on the colloidal structure. This work is a preliminary investigation into the cross-administration of PEGylated nanocarriers, and our observations can have serious implications for the design of combination therapies that use PEGylated vectors. PMID:25999716

Hemolytic anemia and metabolic acidosis: think about glutathione synthetase deficiency.

PubMed

Ben Ameur, Salma; Aloulou, Hajer; Nasrallah, Fehmi; Kamoun, Thouraya; Kaabachi, Naziha; Hachicha, Mongia

2015-02-01

Glutathione synthetase deficiency (GSSD) is a rare disorder of glutathione metabolism with varying clinical severity. Patients may present with hemolytic anemia alone or together with acidosis and central nervous system impairment. Diagnosis is made by clinical presentation and detection of elevated concentrations of 5-oxoproline in urine and low glutathione synthetase activity in erythrocytes or cultured skin fibroblasts. The prognosis seems to depend on early diagnosis and treatment. We report a 4 months old Tunisian male infant who presented with severe metabolic acidosis with high anion gap and hemolytic anemia. High level of 5-oxoproline was detected in her urine and diagnosis of GSSD was made. Treatment consists of the correction of acidosis, blood transfusion, and supplementation with antioxidants. He died of severe metabolic acidosis and sepsis at the age of 15 months.

Polymer-Based Nanocarriers for Co-Delivery and Combination of Diverse Therapies against Cancers

PubMed Central

Yan, Guowen; Li, Aihua; Zhang, Aitang; Sun, Yong; Liu, Jingquan

2018-01-01

Cancer gives rise to an enormous number of deaths worldwide nowadays. Therefore, it is in urgent need to develop new therapies, among which combined therapies including photothermal therapy (PTT) and chemotherapy (CHT) using polymer-based nanocarriers have attracted enormous interest due to the significantly enhanced efficacy and great progress has been made so far. The preparation of such nanocarriers is a comprehensive task involving the cooperation of nanomaterial science and biomedicine science. In this review, we try to introduce and analyze the structure, preparation and synergistic therapeutic effect of various polymer-based nanocarriers composed of anti-tumor drugs, nano-sized photothermal materials and other possible parts. Our effort may bring benefit to future exploration and potential applications of similar nanocarriers. PMID:29401694

Complement mutations in diacylglycerol kinase-ε-associated atypical hemolytic uremic syndrome.

PubMed

Sánchez Chinchilla, Daniel; Pinto, Sheila; Hoppe, Bernd; Adragna, Marta; Lopez, Laura; Justa Roldan, Maria Luisa; Peña, Antonia; Lopez Trascasa, Margarita; Sánchez-Corral, Pilar; Rodríguez de Córdoba, Santiago

2014-09-05

Atypical hemolytic uremic syndrome is characterized by vascular endothelial damage caused by complement dysregulation. Consistently, complement inhibition therapies are highly effective in most patients with atypical hemolytic uremic syndrome. Recently, it was shown that a significant percentage of patients with early-onset atypical hemolytic uremic syndrome carry mutations in diacylglycerol kinase-ε, an intracellular protein with no obvious role in complement. These data support an alternative, complement-independent mechanism leading to thrombotic microangiopathy that has implications for treatment of early-onset atypical hemolytic uremic syndrome. To get additional insights into this new form of atypical hemolytic uremic syndrome, the diacylglycerol kinase-ε gene in a cohort with atypical hemolytic uremic syndrome was analyzed. Eighty-three patients with early-onset atypical hemolytic uremic syndrome (<2 years) enrolled in the Spanish atypical hemolytic uremic syndrome registry between 1999 and 2013 were screened for mutations in diacylglycerol kinase-ε. These patients were also fully characterized for mutations in the genes encoding factor H, membrane cofactor protein, factor I, C3, factor B, and thrombomodulin CFHRs copy number variations and rearrangements, and antifactor H antibodies. Four patients carried mutations in diacylglycerol kinase-ε, one p.H536Qfs*16 homozygote and three compound heterozygotes (p.W322*/p.P498R, two patients; p.Q248H/p.G484Gfs*10, one patient). Three patients also carried heterozygous mutations in thrombomodulin or C3. Extensive plasma infusions controlled atypical hemolytic uremic syndrome recurrences and prevented renal failure in the two patients with diacylglycerol kinase-ε and thrombomodulin mutations. A positive response to plasma infusions and complement inhibition treatment was also observed in the patient with concurrent diacylglycerol kinase-ε and C3 mutations. Data suggest that complement dysregulation influences

Complement Mutations in Diacylglycerol Kinase-ε–Associated Atypical Hemolytic Uremic Syndrome

PubMed Central

Sánchez Chinchilla, Daniel; Pinto, Sheila; Hoppe, Bernd; Adragna, Marta; Lopez, Laura; Justa Roldan, Maria Luisa; Peña, Antonia; Lopez Trascasa, Margarita; Sánchez-Corral, Pilar; Rodríguez de Córdoba, Santiago

2014-01-01

Background and objectives Atypical hemolytic uremic syndrome is characterized by vascular endothelial damage caused by complement dysregulation. Consistently, complement inhibition therapies are highly effective in most patients with atypical hemolytic uremic syndrome. Recently, it was shown that a significant percentage of patients with early-onset atypical hemolytic uremic syndrome carry mutations in diacylglycerol kinase-ε, an intracellular protein with no obvious role in complement. These data support an alternative, complement-independent mechanism leading to thrombotic microangiopathy that has implications for treatment of early-onset atypical hemolytic uremic syndrome. To get additional insights into this new form of atypical hemolytic uremic syndrome, the diacylglycerol kinase-ε gene in a cohort with atypical hemolytic uremic syndrome was analyzed. Design, setting, participants, & measurements Eighty-three patients with early-onset atypical hemolytic uremic syndrome (<2 years) enrolled in the Spanish atypical hemolytic uremic syndrome registry between 1999 and 2013 were screened for mutations in diacylglycerol kinase-ε. These patients were also fully characterized for mutations in the genes encoding factor H, membrane cofactor protein, factor I, C3, factor B, and thrombomodulin CFHRs copy number variations and rearrangements, and antifactor H antibodies. Results Four patients carried mutations in diacylglycerol kinase-ε, one p.H536Qfs*16 homozygote and three compound heterozygotes (p.W322*/p.P498R, two patients; p.Q248H/p.G484Gfs*10, one patient). Three patients also carried heterozygous mutations in thrombomodulin or C3. Extensive plasma infusions controlled atypical hemolytic uremic syndrome recurrences and prevented renal failure in the two patients with diacylglycerol kinase-ε and thrombomodulin mutations. A positive response to plasma infusions and complement inhibition treatment was also observed in the patient with concurrent diacylglycerol

A systematic review on nanoencapsulation of food bioactive ingredients and nutraceuticals by various nanocarriers.

PubMed

Assadpour, Elham; Jafari, Seid Mahdi

2018-06-08

Today, there is an ever-growing interest on natural food ingredients both by consumers and producers in the food industry. In fact, people are looking for those products in the market which are free from artificial and synthetic additives and can promote their health. These food bioactive ingredients should be formulated in such a way that protects them against harsh process and environmental conditions and safely could be delivered to the target organs and cells. Nanoencapsulation is a perfect strategy for this situation and there have been many studies in recent years for nanoencapsulation of food components and nutraceuticals by different technologies. In this review paper, our main goal is firstly to have an overview of nanoencapsulation techniques applicable to food ingredients in a systematic classification, i.e., lipid-based nanocarriers, nature-inspired nanocarriers, special-equipment-based nanocarriers, biopolymer nanocarriers, and other miscellaneous nanocarriers. Then, application of these cutting-edge nanocarriers for different nutraceuticals including phenolic compounds and antioxidants, natural food colorants, antimicrobial agents and essential oils, vitamins, minerals, flavors, fish oils and essential fatty acids will be discussed along with presenting some examples in each field.

Tumor-targeting delivery of herb-based drugs with cell-penetrating/tumor-targeting peptide-modified nanocarriers

PubMed Central

Kebebe, Dereje; Liu, Yuanyuan; Wu, Yumei; Vilakhamxay, Maikhone; Liu, Zhidong; Li, Jiawei

2018-01-01

Cancer has become one of the leading causes of mortality globally. The major challenges of conventional cancer therapy are the failure of most chemotherapeutic agents to accumulate selectively in tumor cells and their severe systemic side effects. In the past three decades, a number of drug delivery approaches have been discovered to overwhelm the obstacles. Among these, nanocarriers have gained much attention for their excellent and efficient drug delivery systems to improve specific tissue/organ/cell targeting. In order to enhance targeting efficiency further and reduce limitations of nanocarriers, nanoparticle surfaces are functionalized with different ligands. Several kinds of ligand-modified nanomedicines have been reported. Cell-penetrating peptides (CPPs) are promising ligands, attracting the attention of researchers due to their efficiency to transport bioactive molecules intracellularly. However, their lack of specificity and in vivo degradation led to the development of newer types of CPP. Currently, activable CPP and tumor-targeting peptide (TTP)-modified nanocarriers have shown dramatically superior cellular specific uptake, cytotoxicity, and tumor growth inhibition. In this review, we discuss recent advances in tumor-targeting strategies using CPPs and their limitations in tumor delivery systems. Special emphasis is given to activable CPPs and TTPs. Finally, we address the application of CPPs and/or TTPs in the delivery of plant-derived chemotherapeutic agents. PMID:29563797

Temperature-Responsive Smart Nanocarriers for Delivery Of Therapeutic Agents: Applications and Recent Advances.

PubMed

Karimi, Mahdi; Sahandi Zangabad, Parham; Ghasemi, Alireza; Amiri, Mohammad; Bahrami, Mohsen; Malekzad, Hedieh; Ghahramanzadeh Asl, Hadi; Mahdieh, Zahra; Bozorgomid, Mahnaz; Ghasemi, Amir; Rahmani Taji Boyuk, Mohammad Reza; Hamblin, Michael R

2016-08-24

Smart drug delivery systems (DDSs) have attracted the attention of many scientists, as carriers that can be stimulated by changes in environmental parameters such as temperature, pH, light, electromagnetic fields, mechanical forces, etc. These smart nanocarriers can release their cargo on demand when their target is reached and the stimulus is applied. Using the techniques of nanotechnology, these nanocarriers can be tailored to be target-specific, and exhibit delayed or controlled release of drugs. Temperature-responsive nanocarriers are one of most important groups of smart nanoparticles (NPs) that have been investigated during the past decades. Temperature can either act as an external stimulus when heat is applied from the outside, or can be internal when pathological lesions have a naturally elevated termperature. A low critical solution temperature (LCST) is a special feature of some polymeric materials, and most of the temperature-responsive nanocarriers have been designed based on this feature. In this review, we attempt to summarize recent efforts to prepare innovative temperature-responsive nanocarriers and discuss their novel applications.

Clostridium septicum infection and hemolytic uremic syndrome.

PubMed Central

Barnham, M.; Weightman, N.

1998-01-01

Five cases of Clostridium septicum infection secondary to Escherichia coli O157-induced hemolytic uremic syndrome have been reported. We report on three cases (one of which is included in the above five) of dual Cl. septicum and E. coil infection; all three patients were exposed to farm animals. A common zoonotic source for Cl. septicum and E. coli O157 infections should be considered. Patients with hemolytic uremic syndrome should be treated aggressively and monitored closely for Cl. septicum superinfection. PMID:9621207

Polycaprolactone/maltodextrin nanocarrier for intracellular drug delivery: formulation, uptake mechanism, internalization kinetics, and subcellular localization.

PubMed

Korang-Yeboah, Maxwell; Gorantla, Yamini; Paulos, Simon A; Sharma, Pankaj; Chaudhary, Jaideep; Palaniappan, Ravi

2015-01-01

Prostate cancer (PCa) disease progression is associated with significant changes in intracellular and extracellular proteins, intracellular signaling mechanism, and cancer cell phenotype. These changes may have direct impact on the cellular interactions with nanocarriers; hence, there is the need for a much-detailed understanding, as nanocarrier cellular internalization and intracellular sorting mechanism correlate directly with bioavailability and clinical efficacy. In this study, we report the differences in the rate and mechanism of cellular internalization of a biocompatible polycaprolactone (PCL)/maltodextrin (MD) nanocarrier system for intracellular drug delivery in LNCaP, PC3, and DU145 PCa cell lines. PCL/MD nanocarriers were designed and characterized. PCL/MD nanocarriers significantly increased the intracellular concentration of coumarin-6 and fluorescein isothiocyanate-labeled bovine serum albumin, a model hydrophobic and large molecule, respectively. Fluorescence microscopy and flow cytometry analysis revealed rapid internalization of the nanocarrier. The extent of nanocarrier cellular internalization correlated directly with cell line aggressiveness. PCL/MD internalization was highest in PC3 followed by DU145 and LNCaP, respectively. Uptake in all PCa cell lines was metabolically dependent. Extraction of endogenous cholesterol by methyl-β-cyclodextrin reduced uptake by 75%±4.53% in PC3, 64%±6.01% in LNCaP, and 50%±4.50% in DU145, indicating the involvement of endogenous cholesterol in cellular internalization. Internalization of the nanocarrier in LNCaP was mediated mainly by macropinocytosis and clathrin-independent pathways, while internalization in PC3 and DU145 involved clathrin-mediated endocytosis, clathrin-independent pathways, and macropinocytosis. Fluorescence microscopy showed a very diffused and non-compartmentalized subcellular localization of the PCL/MD nanocarriers with possible intranuclear localization and minor colocalization in

Targeted transport of nanocarriers into brain for theranosis with rabies virus glycoprotein-derived peptide.

PubMed

Fu, Chen; Xiang, Yonggang; Li, Xiaorong; Fu, Ailing

2018-06-01

For successful theranosis of brain diseases, limited access of therapeutic molecules across blood-brain barrier (BBB) needs be overcome in brain delivery. Currently, peptide derivatives of rabies virus glycoprotein (RVG) have been exploited as delivery ligands to transport nanocarriers across BBB and specifically into the brain. The targeting peptides usually conjugate to the nanocarrier surface, and the cargoes, including siRNA, miRNA, DNA, proteins and small molecular chemicals, are complexed or encapsulated in the nanocarriers. The peptide ligand of the RVG-modified nanocarriers introduces the conjugated targeted-delivery into the brain, and the cargoes are involved in disease theranosis. The peptide-modified nanocarriers have been applied to diagnose and treat various brain diseases, such as glioma, Alzheimer's disease, ischemic injury, protein misfolding diseases etc. Since the targeting delivery system has displayed good biocompatibility and desirable therapeutic effect, it will raise a potential application in treating brain diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Emerging role of nanocarriers to increase the solubility and bioavailability of curcumin.

PubMed

Mohanty, Chandana; Das, Manasi; Sahoo, Sanjeeb K

2012-11-01

Curcumin is a safe, affordable and natural bioactive molecule of turmeric (Curcuma longa). It has gained considerable attention in recent years for its multiple pharmacological activities. However, its optimum pharmaceutical potential has been limited by its lack of aqueous solubility and poor bioavailability. To mitigate the above limitations, recently various nanostructured water-soluble delivery systems were developed to increase the solubility and bioavailability of curcumin. Major reasons contributing to the low bioavailability of curcumin appear to be owing to its poor solubility, low absorption, rapid metabolism and rapid systemic elimination. The present review summarizes the strategies using curcumin in various nanocarrier delivery systems to overcome poor solubility and inconsistent bioavailability of curcumin and describes the current status and challenges for the future. The development of various drug delivery systems to deliver curcumin will certainly provide a step up towards augmenting the therapeutic activity of curcumin thereby increasing the solubility and bioavailability of curcumin. However, the future of such delivery technology will be highly dependent on the development of safe, non-toxic and non-immunogenic nanocarriers.

A hemolytic factor from Haemonchus contortus alters erythrocyte morphology.

PubMed

Fetterer, R H; Rhoads, M L

1998-12-15

A hemolytic factor from adult Haemonchus contortus caused distinct morphological changes in the surface of sheep red blood cells (RBCs). After a 15 min exposure to the hemolytic factor, hemolysis was not detected in incubation media, but RBCs were spherical in shape with numerous surface projections compared to control cells that were smooth-surfaced biconcave disks. After 30 min, a time at which significant hemolysis occurred, echinocytes were formed, and after 90 min, cells were severely disrupted with many visible holes in membranes. No RBC ghosts were observed. RBCs from four other mammalian species were lysed by the H. contortus hemolytic factor. However, the rate of hemolysis varied with a relative order of sheep approximately rabbit>goat>pig>calf. The morphology of RBCs from all four species was significantly altered after 30 min incubation with the degree of morphological changes related to the degree of hemolysis. These results support the hypothesis that the hemolytic factor acts as a pore-forming agent, although a phospholipase or other enzyme might play a role in solubilization of cell membranes.

Red blood cell vesiculation in hereditary hemolytic anemia

PubMed Central

Alaarg, Amr; Schiffelers, Raymond M.; van Solinge, Wouter W.; van Wijk, Richard

2013-01-01

Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias. PMID

[Hemolytic anemia due to hemoglobin Evans in an Argentinean family].

PubMed

Zanotto, María I; Calvo, Karina; Schvartzman, Gabriel; Deana, Alejandra; Noguera, Nélida; Bragós, Irma; Milani, Angela

2010-12-01

Unstable hemoglobins are structural variants of the hemoglobin molecule, mostly originated by single amino-acid replacement in some globin chains. These changes affect molecule stability, leading to loss of solubility, precipitation, and cellular lysis. Patients carrying these unstable hemoglobins may present mild to severe chronic hemolytic anemia. Hemoglobin Evans is an unstable variant originated by replacement of valine with methionine at position 62 of the α-globin chain. We have identified this variant in a girl with an acute hemolytic crisis associated to pharyngitis, as well as in two of her family members. This is the third case of hemolytic anemia due to hemoglobin Evans reported in the literature.

The Research and Applications of Quantum Dots as Nano-Carriers for Targeted Drug Delivery and Cancer Therapy

NASA Astrophysics Data System (ADS)

Zhao, Mei-Xia; Zhu, Bing-Jie

2016-04-01

Quantum dots (QDs), nano-carriers for drugs, can help realize the targeting of drugs, and improve the bioavailability of drugs in biological fields. And, a QD nano-carrier system for drugs has the potential to realize early detection, monitoring, and localized treatments of specific disease sites. In addition, QD nano-carrier systems for drugs can improve stability of drugs, lengthen circulation time in vivo, enhance targeted absorption, and improve the distribution and metabolism process of drugs in organization. So, the development of QD nano-carriers for drugs has become a hotspot in the fields of nano-drug research in recent years. In this paper, we review the advantages and applications of the QD nano-carriers for drugs in biological fields.

Pernicious anemia associated with autoimmune hemolytic anemia and alopecia areata.

PubMed

Zafad, Saadia; Madani, Abdellah; Harif, Mhamed; Quessar, Asmaa; Benchekroun, Said

2007-12-01

We report a 16-year-old male with a combination of pernicious anemia, auto-immune hemolytic anemia and alopecia areata. Autoimmune hemolytic anemia coexisted with pernicious anemia but was diagnosed only when the anemia failed to respond to cobalamin therapy. Alopecia areata occurred 9 years later. 2007 Wiley-Liss, Inc

Transdermal Drug Delivery: Opportunities and Challenges for Controlled Delivery of Therapeutic Agents Using Nanocarriers.

PubMed

Kurmi, Balak Das; Tekchandani, Pawan; Paliwal, Rishi; Paliwal, Shivani Rai

2017-01-01

Transdermal drug delivery represents an extremely attractive and innovative route across the skin owing to the possibility for achieving systemic effect of drugs. The present scenario demands a special focus on developing safe medicine with minimized toxic adverse effects related to most of the pharmacologically active agents. Transdermal drug delivery would be a focal paradigm which provides patient convenience, first-pass hepatic metabolism avoidance, local targeting and reduction in toxic effect related to various categories of drugs like, analgesics, antiinflammatory, antibiotics, antiviral, anaesthetic, anticancer etc. Even this route has challenges due to highly organized structure of skin which acts as a main barrier to penetration of drug via the skin. Several alternative possible strategies are available which overcome these barriers, including use of penetration enhancer, eletroporation, iontophoresis and various nanotechnologically developed nanocarrier systems. The latest one includes employing liposome, dendrimers, nanoparticles, ethosome, carbon nanotube and many more to avoid associated limitations of conventional formulations. Numerous transdermal products such as Estrasorb, Diractin, VivaGel®, Daytrana®, Aczone, Sileryst® are available in the market having a novel strategy to achieve higher penetration of drugs. This encourages formulation fraternity to develop structurally deformable and stable nanocarriers as an alternative approach for controlled and reliable drug delivery across the skin barrier. In this review, we will discuss nanocarriers mediated approaches that come-up with the solutions to the different challenges towards transdermal drug delivery, its clinical importance and latest insight to research in it. The reports presented in this review confirm the wide application of nanocarriers for transdermal delivery of drug/gene. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Novel nanocarriers for topical drug delivery: investigating delivery efficiency and distribution in skin using two-photon microscopy

NASA Astrophysics Data System (ADS)

Kirejev, Vladimir; Guldbrand, Stina; Bauer, Brigitte; Smedh, Maria; Ericson, Marica B.

2011-03-01

The complex structure of skin represents an effective barrier against external environmental factors, as for example, different chemical and biochemical compounds, yeast, bacterial and viral infections. However, this impermeability prevents efficient transdermal drug delivery which limits the number of drugs that are able to penetrate the skin efficiently. Current trends in drug application through skin focus on the design and use of nanocarriers for transport of active compounds. The transport systems applied so far have several drawbacks, as they often have low payload, high toxicity, a limited variability of inclusion molecules, or long degradation times. The aim of these current studies is to investigate novel topical drug delivery systems, e.g. nanocarriers based on cyclic oligosaccharides - cyclodextrins (CD) or iron (III)-based metal-organic frameworks (MOF). Earlier studies on cell cultures imply that these drug nanocarriers show promising characteristics compared to other drug delivery systems. In our studies, we use two-photon microscopy to investigate the ability of the nanocarriers to deliver compounds through ex-vivo skin samples. Using near infrared light for excitation in the so called optical window of skin allows deep-tissue visualization of drug distribution and localization. In addition, it is possible to employ two-photon based fluorescence correlation spectroscopy for quantitative analysis of drug distribution and concentrations in different cell layers.

Nanovaccines : nanocarriers for antigen delivery.

PubMed

Gonzalez-Aramundiz, Jose Vicente; Cordeiro, Ana Sara; Csaba, Nœmi; de la Fuente, Maria; Alonso, María José

2012-01-01

Vaccination has become one of the most important health interventions of our times, revolutionizing health care, and improving the quality of life and life expectancy of millions all over the world. In spite of this, vaccine research remains a vast field for innovation and improvement. Indeed, the shift towards the use of sub-unit antigens, much safer but less immunogenic, and the recognized need to facilitate the access to vaccines in the global framework is currently stimulating the search for safe and efficient adjuvants and delivery technologies. Within this context, nanocarriers have gained particular attention over the last years and appear as one of the most promising strategies for antigen delivery. A number of biomaterials and technologies can be used to design nanovaccines that fulfill the requirements of new vaccination approaches, such as single-dose and transmucosal immunization, critical for achieving a widespread coverage while reducing the overall costs in relation to traditional forms of vaccination. Here we present an overview of the current state of nanocarriers for antigen delivery, developed with the perspective of contributing to the global vaccination goal. © Société de Biologie, 2013.

Nanocarrier-mediated drugs targeting cancer stem cells: an emerging delivery approach.

PubMed

Malhi, Sarandeep; Gu, Xiaochen

2015-07-01

Cancer stem cells (CSCs) play an important role in the development of drug resistance, metastasis and recurrence. Current conventional therapies do not commonly target CSCs. Nanocarrier-based delivery systems targeting cancer cells have entered a new era of treatment, where specific targeting to CSCs may offer superior outcomes to efficient cancer therapies. This review discusses the involvement of CSCs in tumor progression and relevant mechanisms associated with CSCs resistance to conventional chemo- and radio-therapies. It highlights CSCs-targeted strategies that are either under evaluation or could be explored in the near future, with a focus on various nanocarrier-based delivery systems of drugs and nucleic acids to CSCs. Novel nanocarriers targeting CSCs are presented in a cancer-specific way to provide a current perspective on anti-CSCs therapeutics. The field of CSCs-targeted therapeutics is still emerging with a few small molecules and macromolecules currently proving efficacy in clinical trials. However considering the complexities of CSCs and existing delivery difficulties in conventional anticancer therapies, CSC-specific delivery systems would face tremendous technical and clinical challenges. Nanocarrier-based approaches have demonstrated significant potential in specific drug delivery and targeting; their success in CSCs-targeted drug delivery would not only significantly enhance anticancer treatment but also address current difficulties associated with cancer resistance, metastasis and recurrence.

Platform for Lipid Based Nanocarriers' Formulation Components and their Potential Effects: A Literature Review.

PubMed

Farid, Ragwa Mohamed; Youssef, Nancy Abdel Hamid Abou; Kassem, Abeer Ahmed

2017-11-27

Lipid based nanocarriers have gained recently enormous interest for pharmaceutical application. They have the potential to provide controlled drug release and to target the drug to a specific area. In addition, lipid based nanocarriers can improve the bioavailability of drugs suffering from high hepatic first-pass metabolism, by enhancing their transport via the lymphatic system. The main components of lipid based nanocarriers are lipids and surfactants. Both have great influence on the prepared lipid based systems characteristics. The criteria for their selection are much related to physicochemical properties of the drug and the required administration route. This work gives an overview on the effect of both the type and amount of lipids and surfactants used in the manufacture of lipid based nanocarriers on their behavior and characteristics. Recent studies revealed that the properties of the final product including; particle size, homogeneity, drug loading capacity, zeta potential, drug release profile, stability, permeability, pharmacokinetic properties, crystallinity and cytotoxicity, may be significantly influenced not only by the type but also the amount of the lipids and/or surfactants included in the formulation of the lipid based nanocarriers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Medicago truncatula CYP716A12 Is a Multifunctional Oxidase Involved in the Biosynthesis of Hemolytic Saponins[W

PubMed Central

Carelli, Maria; Biazzi, Elisa; Panara, Francesco; Tava, Aldo; Scaramelli, Laura; Porceddu, Andrea; Graham, Neil; Odoardi, Miriam; Piano, Efisio; Arcioni, Sergio; May, Sean; Scotti, Carla; Calderini, Ornella

2011-01-01

Saponins, a group of glycosidic compounds present in several plant species, have aglycone moieties that are formed using triterpenoid or steroidal skeletons. In spite of their importance as antimicrobial compounds and their possible benefits for human health, knowledge of the genetic control of saponin biosynthesis is still poorly understood. In the Medicago genus, the hemolytic activity of saponins is related to the nature of their aglycone moieties. We have identified a cytochrome P450 gene (CYP716A12) involved in saponin synthesis in Medicago truncatula using a combined genetic and biochemical approach. Genetic loss-of-function analysis and complementation studies showed that CYP716A12 is responsible for an early step in the saponin biosynthetic pathway. Mutants in CYP716A12 were unable to produce hemolytic saponins and only synthetized soyasaponins, and were thus named lacking hemolytic activity (lha). In vitro enzymatic activity assays indicate that CYP716A12 catalyzes the oxidation of β-amyrin and erythrodiol at the C-28 position, yielding oleanolic acid. Transcriptome changes in the lha mutant showed a modulation in the main steps of triterpenic saponin biosynthetic pathway: squalene cyclization, β-amyrin oxidation, and glycosylation. The analysis of CYP716A12 expression in planta is reported together with the sapogenin content in different tissues and stages. This article provides evidence for CYP716A12 being a key gene in hemolytic saponin biosynthesis. PMID:21821776

Nanotechnology and nanocarrier-based approaches on treatment of degenerative diseases

NASA Astrophysics Data System (ADS)

Chowdhury, Anindita; Kunjiappan, Selvaraj; Panneerselvam, Theivendren; Somasundaram, Balasubramanian; Bhattacharjee, Chiranjib

2017-04-01

Degenerative diseases are results of deterioration of cells and tissues with aging either by unhealthy lifestyle or normal senescence. The degenerative disease likely affects central nervous system and cardiovascular system to a great extent. Certain medications and therapies have emerged for the treatment of degenerative diseases, but in most cases bearing with poor solubility, lower bioavailability, drug resistance, and incapability to cross the blood-brain barrier (BBB). Hence, it has to be overcome with conventional treatment system; in this connection, nanotechnology has gained a great deal of interest in recent years. Moreover, nanotechnology and nanocarrier-based approach drug delivery system could revolutionize the treatment of degenerative diseases by faster absorption of drug, targeted interaction at specific site, and its release in a controlled manner into human body with minimal side effects. The core objective of this review is to customize and formulate therapeutically active molecules with specific site of action and without affecting other organs and tissues to obtain effective result in the improvement of quality of health. In addition, the review provides a concise insight into the recent developments and applications of nanotech and nanocarrier-based drug delivery for the treatment of various degenerative diseases.

Evaluation of Doxorubicin-loaded 3-Helix Micelles as Nanocarriers

PubMed Central

Dube, Nikhil; Shu, Jessica Y.; Dong, He; Seo, Jai W.; Ingham, Elizabeth; Kheirolomoom, Azadeh; Chen, Pin-Yuan; Forsayeth, John; Bankiewicz, Krystof; Ferrara, Katherine W.; Xu, Ting

2013-01-01

Designing stable drug nanocarriers, 10-30 nm in size, would have significant impact on their transport in circulation, tumor penetration and therapeutic efficacy. In the present study, biological properties of 3-helix micelles loaded with 8 wt% doxorubicin (DOX), ~15 nm in size, were characterized to validate their potential as a nanocarrier platform. DOX-loaded micelles exhibited high stability in terms of size and drug retention in concentrated protein environments similar to conditions after intravenous injections. DOX-loaded micelles were cytotoxic to PPC-1 and 4T1 cancer cells at levels comparable to free DOX. 3-helix micelles can be disassembled by proteolytic degradation of peptide shell to enable drug release and clearance to minimize long-term accumulation. Local administration to normal rat striatum by convection enhanced delivery (CED) showed greater extent of drug distribution and reduced toxicity relative to free drug. Intravenous administration of DOX-loaded 3-helix micelles demonstrated improved tumor half-life and reduced toxicity to healthy tissues in comparison to free DOX. In vivo delivery of DOX-loaded 3-helix micelles through two different routes clearly indicates the potential of 3-helix micelles as safe and effective nanocarriers for cancer therapeutics. PMID:24050265

Nanocarrier-Integrated Microspheres: Nanogel Tectonic Engineering for Advanced Drug-Delivery Systems.

PubMed

Tahara, Yoshiro; Mukai, Sada-Atsu; Sawada, Shin-Ichi; Sasaki, Yoshihiro; Akiyoshi, Kazunari

2015-09-09

A nanocarrier-integrated bottom-up method is a promising strategy for advanced drug-release systems. Self-assembled nanogels, which are one of the most beneficial nanocarriers for drug-delivery systems, are tectonically integrated to prepare nanogel-crosslinked (NanoClik) microspheres. NanoClik microspheres consisting of nanogel-derived structures (observed by STED microscopy) release "drug-loaded nanogels" after hydrolysis, resulting in successful sustained drug delivery in vivo. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Superiority of liquid crystalline cubic nanocarriers as hormonal transdermal vehicle: comparative human skin permeation-supported evidence.

PubMed

Mohyeldin, Salma M; Mehanna, Mohammed M; Elgindy, Nazik A

2016-08-01

The aim of this investigation was to explore the feasibility of various nanocarriers to enhance progesterone penetration via the human abdominal skin. Four progesterone-loaded nanocarriers; cubosomes, nanoliposomes, nanoemulsions and nanomicelles were formulated and characterized regarding particle size, zeta potential, % drug encapsulation and in vitro release. Structural elucidation of each nanoplatform was performed using transmission electron microscopy. Ex vivo skin permeation, deposition ability and histopathological examination were evaluated using Franz diffusion cells. Each nanocarrier was fabricated with a negative surface, nanometric size (≤ 270 nm), narrow size distribution and reasonable encapsulation efficiency. In vitro progesterone release showed a sustained release pattern for 24 h following a non-Fickian transport diffusion mechanism. All nanocarriers exhibited higher transdermal flux relative to free progesterone. Cubosomes revealed a higher skin penetration with transdermal steady flux of 48.57.10(-2) ± 0.7 µg/cm(2) h. Nanoliposomes offered a higher percentage of skin progesterone deposition compared to other nanocarriers. Based on the histopathological examination, cubosomes and nanoliposomes were found to be biocompatible for transdermal application. Confocal laser scanning microscopy confirmed the ability of fluoro-labeled cubosomes to penetrate through the whole skin layers. The elaborated cubosomes proved to be a promising non-invasive nanocarrier for transdermal hormonal delivery.

Multifunctional Triblock Nanocarrier (PAMAM-PEG-PLL) for the Efficient Intracellular siRNA Delivery and Gene Silencing

PubMed Central

2011-01-01

A novel triblock poly(amido amine)-poly(ethylene glycol)-poly-l-lysine (PAMAM-PEG-PLL) nanocarrier was designed, synthesized, and evaluated for the delivery of siRNA. The design of the nanocarrier is unique and provides a solution to most of the common problems associated with the delivery and therapeutic applications of siRNA. Every component in the triblock nanocarrier plays a significant role and performs multiple functions: (1) tertiary amine groups in the PAMAM dendrimer work as a proton sponge and play a vital role in the endosomal escape and cytoplasmic delivery of siRNA; (2) PEG, a linker connecting PLL and PAMAM dendrimers renders nuclease stability and protects siRNA in human plasma; (3) PLL provides primary amines to form polyplexes with siRNA through electrostatic interaction and also acts as penetration enhancer; and (4) conjugation to PEG and PAMAM reduced toxicity of PLL and the entire triblock nanocarrier PAMAM-PEG-PLL. The data obtained show that the polyplexes resulted from the conjugation of siRNA, and the proposed nanocarriers were effectively taken up by cancer cells and induced the knock down of the target BCL2 gene. In addition, triblock nanocarrier/siRNA polyplexes showed excellent stability in human plasma. PMID:21322531

Genetically engineered nanocarriers for drug delivery.

PubMed

Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

2014-01-01

Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins.

Genetically engineered nanocarriers for drug delivery

PubMed Central

Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

2014-01-01

Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins. PMID:24741309

Multiple-Targeted Graphene-based Nanocarrier for Intracellular Imaging of mRNAs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Ying; Li, Zhaohui; Liu, Misha

Simultaneous detection and imaging of multiple intracellular messenger RNA (mRNAs) hold great significant for early cancer diagnostics and preventive medicine development. Herein, we propose a multiple-targeted graphene oxide (GO) nanocarrier that can simultaneously detect and image different type mRNAs in living cells. First of all, in vitro detection of multiple targets have been realized successfully based on the multiple-targeted GO nanocarrier with linear relationship ranging from 3 nM to 200 nM, as well as sensitive detection limit of 1.84 nM for manganese superoxide dismutase (Mn-SOD) mRNA and 2.45 nM for β-actin mRNA. Additionally, this nanosensing platform composed of fluorescent labeledmore » single strand DNA probes and GO nanocarrier can identify Mn-SOD mRNA and endogenous mRNA of β-actin in living cancer cells, showing rapid response, high specificity, nuclease stability, and good biocompatibility during the cell imaging. Thirdly, changes of the expression levels of mRNA in living cells before or after the drug treatment can be monitored successfully. By using multiple ssDNA as probes and GO nanocarrier as the cellular delivery cargo, the proposed simultaneous multiple-targeted sensing platform will be of great potential as a powerful tool for intracellular trafficking process from basic research to clinical diagnosis.« less

Lipid nanocarriers: influence of lipids on product development and pharmacokinetics.

PubMed

Pathak, Kamla; Keshri, Lav; Shah, Mayank

2011-01-01

Lipid nanocarriers are on the forefront of the rapidly developing field of nanotechnology with several potential applications in drug delivery. Owing to their size-dependent properties, lipid nanoparticles offer the possibility for development of new therapeutics and an alternative system to other colloidal counterparts for drug administration. An important point to be considered in the selection of a lipid for the carrier system is its effect on the properties of the nanocarrier and also its intended use, as different types of lipids differ in their nature. Researchers around the globe have tapped the potential of solid lipid nanoparticles (SLNs) in developing formulation(s) that can be administered by various routes such as oral, ocular, parenteral, topical, and pulmonary. Since the start of this millennium, a new generation of lipid nanoparticles, namely nanostructured lipid carriers (NLCs), lipid drug conjugates (LDCs), and pharmacosomes, has evolved that have the potential to overcome the limitations of SLNs. The current review article presents broad considerations on the influence of various types of lipids on the diverse characteristics of nanocarriers, encompassing their physicochemical, formulation, pharmacokinetic, and cytotoxic aspects.

Mucin-mediated nanocarrier disassembly for triggered uptake of oligonucleotides as a delivery strategy for the potential treatment of mucosal tumours

NASA Astrophysics Data System (ADS)

Martirosyan, A.; Olesen, M. J.; Fenton, R. A.; Kjems, J.; Howard, K. A.

2016-06-01

This work demonstrates gastric mucin-triggered nanocarrier disassembly for release of antisense oligonucleotides and consequent unassisted cellular entry as a novel oral delivery strategy. A fluorescence activation-based reporter system was used to investigate the interaction and mucin-mediated disassembly of chitosan-based nanocarriers containing a 13-mer DNA oligonucleotide with a flanked locked RNA nucleic acid gapmer design. Gastric mucins were shown to trigger gapmer release from nanocarriers that was dependent on the interaction time, mucin concentration and N : P ratio with a maximal release at N : P 10. In contrast to siRNA, naked gapmers exhibited uptake into mucus producing HT-MTX mono-cultures and HT-MTX co-cultured with the carcinoma epithelial cell line Caco-2. Importantly, in vivo gapmer uptake was observed in epithelial tissue 30 min post-injection in murine intestinal loops. The findings present a mucosal design-based system tailored for local delivery of oligonucleotides that may maximize the effectiveness of gene silencing therapeutics within tumours at mucosal sites.This work demonstrates gastric mucin-triggered nanocarrier disassembly for release of antisense oligonucleotides and consequent unassisted cellular entry as a novel oral delivery strategy. A fluorescence activation-based reporter system was used to investigate the interaction and mucin-mediated disassembly of chitosan-based nanocarriers containing a 13-mer DNA oligonucleotide with a flanked locked RNA nucleic acid gapmer design. Gastric mucins were shown to trigger gapmer release from nanocarriers that was dependent on the interaction time, mucin concentration and N : P ratio with a maximal release at N : P 10. In contrast to siRNA, naked gapmers exhibited uptake into mucus producing HT-MTX mono-cultures and HT-MTX co-cultured with the carcinoma epithelial cell line Caco-2. Importantly, in vivo gapmer uptake was observed in epithelial tissue 30 min post-injection in murine intestinal

Hemolytic venoms from marine cnidarian jellyfish - an overview.

PubMed

Mariottini, Gian Luigi

2014-01-01

Cnidarian jellyfish are viewed as an emergent problem in several coastal zones throughout the world. Recurrent outbreaks pose a serious threat to tourists and bathers, as well as to sea-workers, involving health and economical aspects. As a rule, cnidarian stinging as a consequence of nematocyst firing induces merely local symptoms but cardiovascular or neurological complications can also occur. Hemolysis is a frequent effect of cnidarian stinging; this dangerous condition is known to be caused by several venoms and can sometimes be lethal. At present, the bulk of data concerning hemolytic cnidarian venoms comes from the study of benthic species, such as sea anemones and soft corals, but hemolytic factors were found in venoms of several siphonophore, cubozoan and scyphozoan jellyfish, which are mainly involved in the envenomation of bathers and sea-workers. Therefore, the aim of this paper is to review the scientific literature concerning the hemolytic venoms from cnidarian jellyfish taking into consideration their importance in human pathology as well as health implications and possible therapeutic measures.

Melatonin Promotes Brain-Derived Neurotrophic Factor (BDNF) Expression and Anti-Apoptotic Effects in Neonatal Hemolytic Hyperbilirubinemia via a Phospholipase (PLC)-Mediated Mechanism

PubMed Central

Luo, Yong; Peng, Mei; Wei, Hong

2017-01-01

Background Melatonin therapy shows positive effects on neuroprotective factor brain-derived neurotrophic factor (BDNF) expression and neuronal apoptosis in neonatal hemolytic hyperbilirubinemia. We hypothesized that melatonin promotes BDNF expression and anti-apoptotic effects in neonatal hemolytic hyperbilirubinemia through a phospholipase (PLC)-mediated mechanism. Material/Methods A phenylhydrazine hydrochloride (PHZ)-induced neonatal hemolytic hyperbilirubinemia model was constructed in neonatal rats. Four experimental groups – a control group (n=30), a PHZ group (n=30), a PHZ + melatonin group (n=30), and a PHZ + melatonin+U73122 (a PLC inhibitor) group (n=30) – were constructed. Trunk blood was assayed for serum hemoglobin, hematocrit, total and direct bilirubin, BDNF, S100B, and tau protein levels. Brain tissue levels of neuronal apoptosis, BDNF expression, PLC activity, IP3 content, phospho- and total Ca2+/calmodulin-dependent protein kinase type IV (CaMKIV) expression, and phospho- and total cAMP response element binding protein (CREB) expression were also assayed. Results PHZ-induced hemolytic hyperbilirubinemia was validated by significantly decreased serum hemoglobin and hematocrit as well as significantly increased total and direct serum bilirubin (p<0.05). Neonatal bilirubin-induced neurotoxicity was validated by significantly decreased serum BDNF, brain BDNF, and serum S100B, along with significantly increased serum tau protein (p<0.05). PHZ-induced hemolytic hyperbilirubinemia significantly decreased serum BDNF, brain BDNF, and PLC/IP3/Ca2+ pathway activation while increasing neuronal apoptosis levels (p<0.05), all of which were partially rescued by melatonin therapy (p<0.05). Pre-treatment with the PLC inhibitor U73122 largely abolished the positive effects of melatonin on PLC/IP3/Ca2+ pathway activation, downstream BDNF levels, and neuronal apoptosis (p<0.05). Conclusions Promotion of BDNF expression and anti-apoptotic effects in neonatal

Factorial Design Based Multivariate Modeling and Optimization of Tunable Bioresponsive Arginine Grafted Poly(cystaminebis(acrylamide)-diaminohexane) Polymeric Matrix Based Nanocarriers.

PubMed

Yang, Rongbing; Nam, Kihoon; Kim, Sung Wan; Turkson, James; Zou, Ye; Zuo, Yi Y; Haware, Rahul V; Chougule, Mahavir B

2017-01-03

Desired characteristics of nanocarriers are crucial to explore its therapeutic potential. This investigation aimed to develop tunable bioresponsive newly synthesized unique arginine grafted poly(cystaminebis(acrylamide)-diaminohexane) [ABP] polymeric matrix based nanocarriers by using L9 Taguchi factorial design, desirability function, and multivariate method. The selected formulation and process parameters were ABP concentration, acetone concentration, the volume ratio of acetone to ABP solution, and drug concentration. The measured nanocarrier characteristics were particle size, polydispersity index, zeta potential, and percentage drug loading. Experimental validation of nanocarrier characteristics computed from initially developed predictive model showed nonsignificant differences (p > 0.05). The multivariate modeling based optimized cationic nanocarrier formulation of <100 nm loaded with hydrophilic acetaminophen was readapted for a hydrophobic etoposide loading without significant changes (p > 0.05) except for improved loading percentage. This is the first study focusing on ABP polymeric matrix based nanocarrier development. Nanocarrier particle size was stable in PBS 7.4 for 48 h. The increase of zeta potential at lower pH 6.4, compared to the physiological pH, showed possible endosomal escape capability. The glutathione triggered release at the physiological conditions indicated the competence of cytosolic targeting delivery of the loaded drug from bioresponsive nanocarriers. In conclusion, this unique systematic approach provides rational evaluation and prediction of a tunable bioresponsive ABP based matrix nanocarrier, which was built on selected limited number of smart experimentation.

Ocular Drug Delivery Barriers-Role of Nanocarriers in the Treatment of Anterior Segment Ocular Diseases.

PubMed

Bachu, Rinda Devi; Chowdhury, Pallabitha; Al-Saedi, Zahraa H F; Karla, Pradeep K; Boddu, Sai H S

2018-02-27

Ocular drug delivery is challenging due to the presence of anatomical and physiological barriers. These barriers can affect drug entry into the eye following multiple routes of administration (e.g., topical, systemic, and injectable). Topical administration in the form of eye drops is preferred for treating anterior segment diseases, as it is convenient and provides local delivery of drugs. Major concerns with topical delivery include poor drug absorption and low bioavailability. To improve the bioavailability of topically administered drugs, novel drug delivery systems are being investigated. Nanocarrier delivery systems demonstrate enhanced drug permeation and prolonged drug release. This review provides an overview of ocular barriers to anterior segment delivery, along with ways to overcome these barriers using nanocarrier systems. The disposition of nanocarriers following topical administration, their safety, toxicity and clinical trials involving nanocarrier systems are also discussed.

Ocular Drug Delivery Barriers—Role of Nanocarriers in the Treatment of Anterior Segment Ocular Diseases

PubMed Central

Bachu, Rinda Devi; Chowdhury, Pallabitha; Al-Saedi, Zahraa H. F.; Karla, Pradeep K.; Boddu, Sai H. S.

2018-01-01

Ocular drug delivery is challenging due to the presence of anatomical and physiological barriers. These barriers can affect drug entry into the eye following multiple routes of administration (e.g., topical, systemic, and injectable). Topical administration in the form of eye drops is preferred for treating anterior segment diseases, as it is convenient and provides local delivery of drugs. Major concerns with topical delivery include poor drug absorption and low bioavailability. To improve the bioavailability of topically administered drugs, novel drug delivery systems are being investigated. Nanocarrier delivery systems demonstrate enhanced drug permeation and prolonged drug release. This review provides an overview of ocular barriers to anterior segment delivery, along with ways to overcome these barriers using nanocarrier systems. The disposition of nanocarriers following topical administration, their safety, toxicity and clinical trials involving nanocarrier systems are also discussed. PMID:29495528

Novel Twin Streptolysin S-Like Peptides Encoded in the sag Operon Homologue of Beta-Hemolytic Streptococcus anginosus

PubMed Central

Tabata, Atsushi; Nakano, Kota; Ohkura, Kazuto; Tomoyasu, Toshifumi; Kikuchi, Ken; Whiley, Robert A.

2013-01-01

Streptococcus anginosus is a member of the anginosus group streptococci, which form part of the normal human oral flora. In contrast to the pyogenic group streptococci, our knowledge of the virulence factors of the anginosus group streptococci, including S. anginosus, is not sufficient to allow a clear understanding of the basis of their pathogenicity. Generally, hemolysins are thought to be important virulence factors in streptococcal infections. In the present study, a sag operon homologue was shown to be responsible for beta-hemolysis in S. anginosus strains by random gene knockout. Interestingly, contrary to pyogenic group streptococci, beta-hemolytic S. anginosus was shown to have two tandem sagA homologues, encoding streptolysin S (SLS)-like peptides, in the sag operon homologue. Gene deletion and complementation experiments revealed that both genes were functional, and these SLS-like peptides were essential for beta-hemolysis in beta-hemolytic S. anginosus. Furthermore, the amino acid sequence of these SLS-like peptides differed from that of the typical SLS of S. pyogenes, especially in their propeptide domain, and an amino acid residue indicated to be important for the cytolytic activity of SLS in S. pyogenes was deleted in both S. anginosus homologues. These data suggest that SLS-like peptides encoded by two sagA homologues in beta-hemolytic S. anginosus may be potential virulence factors with a different structure essential for hemolytic activity and/or the maturation process compared to the typical SLS present in pyogenic group streptococci. PMID:23292771

Lipid based nanocarriers system for topical delivery of photosensitizers.

PubMed

Md, Shadab; Haque, Shadabul; Madheswaran, Thiagarajan; Zeeshan, Farrukh; Meka, Venkata Srikanth; Radhakrishnan, Ammu K; Kesharwani, Prashant

2017-08-01

Topical photodynamic therapy (PDT) is a non-invasive technique used in the treatment of malignant and non-malignant skin diseases. It offers great promise because of its simplicity, enhanced patient compliance, localisation of the photosensitizer, as well as the use of light and oxygen to achieve photocytotoxicity. Despite progress in photosensitizer-mediated topical PDT, its clinical application is limited by poor penetration of photosensitizers through the skin. Therefore, much effort has been made to develop nanocarriers that can tackle the challenges of conventional photosensitizer-mediated PDT for topical delivery. This review discusses recent data on the use of different types of lipid-based nanocarriers in delivering photosensitizer for topical PDT. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pulmonary hypertension in chronic hemolytic anemias: Pathophysiology and treatment.

PubMed

Haw, Alexandra; Palevsky, Harold I

2018-04-01

Pulmonary hypertension has emerged as a major cause of morbidity and mortality in patients with hemoglobinopathies and chronic hemolytic anemias. These hematological diseases include - but are not limited to - sickle cell disease (SCD), thalassemia, paroxysmal nocturnal hematuria, and hereditary spherocytosis. Although most studies have been based on the use of echocardiography as a screening tool for pulmonary hypertension as opposed to the gold standard of right heart catheterization for definitive diagnosis, the association between chronic hemolytic anemia and pulmonary hypertension is evident. Studies have shown that patients with SCD and a tricuspid regurgitant velocity (TRV) ≥ 2.5 m/sec are at increased risk of pulmonary hypertension and are at increased mortality risk. Additional markers of risk of pulmonary hypertension and increased mortality include a pro-BNP >160 pg/mL combined with a 6-min walk distance of <333 m. There is currently a lack of concrete data to support the use of targeted oral pulmonary arterial hypertension therapy in chronic hemolytic anemia. As a result, management is generally targeted towards medical optimization of the underlying anemia. This literature review aims to discuss the pathophysiology, diagnostic and prognostic tools, recent studies and current protocols that are essential in guiding management of pulmonary hypertension in chronic hemolytic anemias. Copyright © 2018 Elsevier Ltd. All rights reserved.

Complement deposition in autoimmune hemolytic anemia is a footprint for difficult-to-detect IgM autoantibodies

PubMed Central

Meulenbroek, Elisabeth M.; de Haas, Masja; Brouwer, Conny; Folman, Claudia; Zeerleder, Sacha S.; Wouters, Diana

2015-01-01

In autoimmune hemolytic anemia autoantibodies against erythrocytes lead to increased clearance of the erythrocytes, which in turn results in a potentially fatal hemolytic anemia. Depending on whether IgG or IgM antibodies are involved, response to therapy is different. Proper identification of the isotype of the anti-erythrocyte autoantibodies is, therefore, crucial. However, detection of IgM autoantibodies can be challenging. We, therefore, set out to improve the detection of anti-erythrocyte IgM. Direct detection using a flow cytometry-based approach did not yield satisfactory improvements. Next, we analyzed whether the presence of complement C3 on a patient’s erythrocytes could be used for indirect detection of anti-erythrocyte IgM. To this end, we fractionated patients’ sera by size exclusion chromatography and tested which fractions yielded complement deposition on erythrocytes. Strikingly, we found that all patients with C3 on their erythrocytes according to standard diagnostic tests had an IgM anti-erythrocyte component that could activate complement, even if no such autoantibody had been detected with any other test. This also included all tested patients with only IgG and C3 on their erythrocytes, who would previously have been classified as having an IgG-only mediated autoimmune hemolytic anemia. Depleting patients’ sera of either IgG or IgM and testing the remaining complement activation confirmed this result. In conclusion, complement activation in autoimmune hemolytic anemia is mostly IgM-mediated and the presence of covalent C3 on patients’ erythrocytes can be taken as a footprint of the presence of anti-erythrocyte IgM. Based on this finding, we propose a diagnostic workflow that will aid in choosing the optimal treatment strategy. PMID:26354757

Small-molecule factor D inhibitors selectively block the alternative pathway of complement in paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome.

PubMed

Yuan, Xuan; Gavriilaki, Eleni; Thanassi, Jane A; Yang, Guangwei; Baines, Andrea C; Podos, Steven D; Huang, Yongqing; Huang, Mingjun; Brodsky, Robert A

2017-03-01

Paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome are diseases of excess activation of the alternative pathway of complement that are treated with eculizumab, a humanized monoclonal antibody against the terminal complement component C5. Eculizumab must be administered intravenously, and moreover some patients with paroxysmal nocturnal hemoglobinuria on eculizumab have symptomatic extravascular hemolysis, indicating an unmet need for additional therapeutic approaches. We report the activity of two novel small-molecule inhibitors of the alternative pathway component Factor D using in vitro correlates of both paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome. Both compounds bind human Factor D with high affinity and effectively inhibit its proteolytic activity against purified Factor B in complex with C3b. When tested using the traditional Ham test with cells from paroxysmal nocturnal hemoglobinuria patients, the Factor D inhibitors significantly reduced complement-mediated hemolysis at concentrations as low as 0.01 μM. Additionally the compound ACH-4471 significantly decreased C3 fragment deposition on paroxysmal nocturnal hemoglobinuria erythrocytes, indicating a reduced potential relative to eculizumab for extravascular hemolysis. Using the recently described modified Ham test with serum from patients with atypical hemolytic uremic syndrome, the compounds reduced the alternative pathway-mediated killing of PIGA -null reagent cells, thus establishing their potential utility for this disease of alternative pathway of complement dysregulation and validating the modified Ham test as a system for pre-clinical drug development for atypical hemolytic uremic syndrome. Finally, ACH-4471 blocked alternative pathway activity when administered orally to cynomolgus monkeys. In conclusion, the small-molecule Factor D inhibitors show potential as oral therapeutics for human diseases driven by the alternative pathway of complement

Cobalt-doped nanohydroxyapatite: synthesis, characterization, antimicrobial and hemolytic studies

NASA Astrophysics Data System (ADS)

Tank, Kashmira P.; Chudasama, Kiran S.; Thaker, Vrinda S.; Joshi, Mihir J.

2013-05-01

Hydroxyapatite (Ca10(PO4)6(OH)2; HAP) is a major mineral component of the calcified tissues, and it has various applications in medicine and dentistry. In the present investigation, cobalt-doped hydroxyapatite (Co-HAP) nanoparticles were synthesized by surfactant-mediated approach and characterized by different techniques. The EDAX was carried out to estimate the amount of doping in Co-HAP. The transmission electron microscopy result suggested the transformation of morphology from needle shaped to spherical type on increasing the doping concentration. The powder XRD study indicated the formation of a new phase of brushite for higher concentration of cobalt. The average particle size and strain were calculated using Williamson-Hall analysis. The average particle size was found to be 30-60 nm. The FTIR study confirmed the presence of various functional groups in the samples. The antimicrobial activity was evaluated against four organisms Pseudomonas aeruginosa and Shigella flexneri as Gram negative as well as Micrococcus luteus and Staphylococcus aureus as Gram positive. The hemolytic test result suggested that all samples were non-hemolytic. The photoluminescence study was carried out to identify its possible applicability as a fluorescent probe.

Nanocarriers in ocular drug delivery: an update review.

PubMed

Wadhwa, Sheetu; Paliwal, Rishi; Paliwal, Shivani Rai; Vyas, S P

2009-01-01

Controlled drug delivery to eye is one of the most challenging fields of pharmaceutical research. Low drug-contact time and poor ocular bioavailability due to drainage of solution, tear turnover and its dilution or lacrimation are the problems associated with conventional systems. In addition, anatomical barriers and physiological conditions of eye are also important parameters which control designing of drug delivery systems. Nanosized carriers like micro/nano-suspensions, liposome, niosome, dendrimer, nanoparticles, ocular inserts, implants, hydrogels and prodrug approaches have been developed for this purpose. These novel systems offer manifold advantages over conventional systems as they increase the efficiency of drug delivery by improving the release profile and also reduce drug toxicity. Conventional delivery systems get diluted with tear, washed away through the lacrimal gland and usually require administering at regular time intervals whereas nanocarriers release drug at constant rate for a prolonged period of time and thus enhance its absorption and site specific delivery. This review presents an overview of the various aspects of the ocular drug delivery, with special emphasis on nanocarrier based strategies, including structure of eye, its barriers, delivery routes and the challenges/limitations associated with development of novel nanocarriers. The recent progresses in therapy of ocular disease like gene therapy have also been included so that future options should also be considered from the delivery point of view. Recent progress in the delivery of proteins and peptides via ocular route has also been incorporated for reader benefit.

A novel Trojan-horse targeting strategy to reduce the non-specific uptake of nanocarriers by non-cancerous cells.

PubMed

Shen, Zheyu; Wu, Hao; Yang, Sugeun; Ma, Xuehua; Li, Zihou; Tan, Mingqian; Wu, Aiguo

2015-11-01

One big challenge with active targeting of nanocarriers is non-specific binding between targeting molecules and non-target moieties expressed on non-cancerous cells, which leads to non-specific uptake of nanocarriers by non-cancerous cells. Here, we propose a novel Trojan-horse targeting strategy to hide or expose the targeting molecules of nanocarriers on-demand. The non-specific uptake by non-cancerous cells can be reduced because the targeting molecules are hidden in hydrophilic polymers. The nanocarriers are still actively targetable to cancer cells because the targeting molecules can be exposed on-demand at tumor regions. Typically, Fe3O4 nanocrystals (FN) as magnetic resonance imaging (MRI) contrast agents were encapsulated into albumin nanoparticles (AN), and then folic acid (FA) and pH-sensitive polymers (PP) were grafted onto the surface of AN-FN to construct PP-FA-AN-FN nanoparticles. Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), transmission electron microscope (TEM) and gel permeation chromatography (GPC) results confirm successful construction of PP-FA-AN-FN. According to difference of nanoparticle-cellular uptake between pH 7.4 and 5.5, the weight ratio of conjugated PP to nanoparticle FA-AN-FN (i.e. graft density) and the molecular weight of PP (i.e. graft length) are optimized to be 1.32 and 5.7 kDa, respectively. In vitro studies confirm that the PP can hide ligand FA to prevent it from binding to cells with FRα at pH 7.4 and shrink to expose FA at pH 5.5. In vivo studies demonstrate that our Trojan-horse targeting strategy can reduce the non-specific uptake of the PP-FA-AN-FN by non-cancerous cells. Therefore, our PP-FA-AN-FN might be used as an accurately targeted MRI contrast agent. Copyright © 2015 Elsevier Ltd. All rights reserved.

Recent advances in galactose-engineered nanocarriers for the site-specific delivery of siRNA and anticancer drugs.

PubMed

Jain, Ashay; Jain, Atul; Parajuli, Prahlad; Mishra, Vijay; Ghoshal, Gargi; Singh, Bhupinder; Shivhare, Uma Shankar; Katare, Om Prakash; Kesharwani, Prashant

2018-05-01

Galactosylated nanocarriers have recently emerged as viable and versatile tools to deliver drugs at an optimal rate specifically to their target tissues or cells, thus maximizing their therapeutic benefits while circumventing off-target effects. The abundance of lectin receptors on cell surfaces makes the galactosylated carriers suitable for the targeted delivery of bioactives. Additionally, tethering of galactose (GAL) to various carriers, including micelles, liposomes, and nanoparticles (NPs), might also be appropriate for drug delivery. Here, we review recent advances in the development of galactosylated nanocarriers for active tumor targeting. We also provide a brief overview of the targeting mechanisms and cell receptor theory involved in the ligand-receptor-mediated delivery of drug carriers. Copyright © 2017 Elsevier Ltd. All rights reserved.

White-Light Supercontinuum Laser-Based Multiple Wavelength Excitation for TCSPC-FLIM of Cutaneous Nanocarrier Uptake

NASA Astrophysics Data System (ADS)

Volz, Pierre; Brodwolf, Robert; Zoschke, Christian; Haag, Rainer; Schäfer-Korting, Monika; Alexiev, Ulrike

2018-05-01

We report here on a custom-built time-correlated single photon-counting (TCSPC)-based fluorescence lifetime imaging microscopy (FLIM) setup with a continuously tunable white-light supercontinuum laser combined with acousto-optical tunable filters (AOTF) as an excitation source for simultaneous excitation of multiple spectrally separated fluorophores. We characterized the wavelength dependence of the white-light supercontinuum laser pulse properties and demonstrated the performance of the FLIM setup, aiming to show the experimental setup in depth together with a biomedical application. We herein summarize the physical-technical parameters as well as our approach to map the skin uptake of nanocarriers using FLIM with a resolution compared to spectroscopy. As an example, we focus on the penetration study of indocarbocyanine-labeled dendritic core-multishell nanocarriers (CMS-ICC) into reconstructed human epidermis. Unique fluorescence lifetime signatures of indocarbocyanine-labeled nanocarriers indicate nanocarrier-tissue interactions within reconstructed human epidermis, bringing FLIM close to spectroscopic analysis.

Cardiovascular Effect Is Independent of Hemolytic Toxicity of Tentacle-Only Extract from the Jellyfish Cyanea capillata

PubMed Central

Qianqian, Wang; Sihua, Liu; Yang, Wang; Guoyan, Liu; Jia, Lu; Xuting, Ye; Liming, Zhang

2012-01-01

Our previous studies have confirmed that the crude tentacle-only extract (cTOE) from the jellyfish Cyanea capillata (Cyaneidae) exhibits hemolytic and cardiovascular toxicities simultaneously. So, it is quite difficult to discern the underlying active component responsible for heart injury caused by cTOE. The inactivation of the hemolytic toxicity from cTOE accompanied with a removal of plenty of precipitates would facilitate the separation of cardiovascular component and the investigation of its cardiovascular injury mechanism. In our research, after the treatment of one-step alkaline denaturation followed by twice dialysis, the protein concentration of the treated tentacle-only extract (tTOE) was about 1/3 of cTOE, and SDS-PAGE showed smaller numbers and lower density of protein bands in tTOE. The hemolytic toxicity of tTOE was completely lost while its cardiovascular toxicity was well retained. The observations of cardiac function, histopathology and ultrastructural pathology all support tTOE with significant cardiovascular toxicity. Blood gas indexes and electrolytes changed far less by tTOE than those by cTOE, though still with significant difference from normal. In summary, the cardiovascular toxicity of cTOE can exist independently of the hemolytic toxicity and tTOE can be employed as a better venom sample for further purification and mechanism research on the jellyfish cardiovascular toxic proteins. PMID:22905209

Pharmaceutical and biomedical applications of lipid-based nanocarriers.

PubMed

Carbone, Claudia; Leonardi, Antonio; Cupri, Sarha; Puglisi, Giovanni; Pignatello, Rosario

2014-03-01

Increasing attention is being given to lipid nanocarriers (LNs) as drug delivery systems, due to the advantages offered of a higher biocompatibility and lower toxicity compared with polymeric nanoparticles. Many administration routes are being investigated for LNs, including topical, oral and parenteral ones. LNs are also proposed for specific applications such as cancer treatment, gene therapy, diagnosis and medical devices production. However, the high number of published research articles does not match an equal amount of patents. A recent Review of ours, published in Pharmaceutical Patent Analyst, reported the patents proposing novel methods for the production of LNs. This review work discusses recent patents, filed in 2007-2013 and dealing with the industrial applications of lipid-based nanocarriers for the vectorization of therapeutically relevant molecules, as well as biotech products such as proteins, gene material and vaccines, in the pharmaceutical, diagnostic and biomedical areas.

Group A beta-hemolytic streptococcal hemorrhagic colitis complicated with pharyngitis and impetigo.

PubMed

Isozaki, Atsushi; Matsubara, Keiko; Yui, Takako; Kobayashi, Kenji; Kawano, Yutaka

2007-12-01

A 6-year-old boy with bloody diarrhea was diagnosed with group A beta-hemolytic streptococcal hemorrhagic colitis. Complications included pharyngitis and impetigo, both caused by the same organisms. In addition to being isolated from stools, Streptococcus pyogenes was also isolated from skin lesions. Furthermore, a rapid group A streptococcal antigen test by throat swab was also positive. Hemorrhagic colitis caused by group A beta-hemolytic streptococcus is extremely rare, and much rarer are its complications with pharyngitis and impetigo. Compared with findings in reports of group A beta-hemolytic streptococcal proctitis and perianal and perineal diseases, this case suggests a distinct pathogenesis for hemorrhagic colitis.

Hemolytic venoms from marine cnidarian jellyfish – an overview

PubMed Central

Mariottini, Gian Luigi

2014-01-01

Cnidarian jellyfish are viewed as an emergent problem in several coastal zones throughout the world. Recurrent outbreaks pose a serious threat to tourists and bathers, as well as to sea-workers, involving health and economical aspects. As a rule, cnidarian stinging as a consequence of nematocyst firing induces merely local symptoms but cardiovascular or neurological complications can also occur. Hemolysis is a frequent effect of cnidarian stinging; this dangerous condition is known to be caused by several venoms and can sometimes be lethal. At present, the bulk of data concerning hemolytic cnidarian venoms comes from the study of benthic species, such as sea anemones and soft corals, but hemolytic factors were found in venoms of several siphonophore, cubozoan and scyphozoan jellyfish, which are mainly involved in the envenomation of bathers and sea-workers. Therefore, the aim of this paper is to review the scientific literature concerning the hemolytic venoms from cnidarian jellyfish taking into consideration their importance in human pathology as well as health implications and possible therapeutic measures. PMID:25386336

[Atypical hemolytic uremic syndrome].

PubMed

Blasco Pelicano, Miquel; Rodríguez de Córdoba, Santiago; Campistol Plana, Josep M

2015-11-20

The hemolytic uremic syndrome (HUS) is a clinical entity characterized by thrombocytopenia, non-immune hemolytic anemia and renal impairment. Kidney pathology shows thrombotic microangiopathy (TMA) with endothelial cell injury leading to thrombotic occlusion of arterioles and capillaries. Traditionally, HUS was classified in 2 forms: Typical HUS, most frequently occurring in children and caused by Shiga-toxin-producing bacteria, and atypical HUS (aHUS). aHUS is associated with mutations in complement genes in 50-60% of patients and has worse prognosis, with the majority of patients developing end stage renal disease. After kidney transplantation HUS may develop as a recurrence of aHUS or as de novo disease. Over the last years, many studies have demonstrated that complement dysregulation underlies the endothelial damage that triggers the development of TMA in most of these patients. Advances in our understanding of the pathogenic mechanisms of aHUS, together with the availability of novel therapeutic options, will enable better strategies for the early diagnosis and etiological treatment, which are changing the natural history of aHUS. This review summarizes the aHUS clinical entity and describes the role of complement dysregulation in the pathogenesis of aHUS. Finally, we review the differential diagnosis and the therapeutic options available to patients with aHUS. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Quantitative analysis of curcumin-loaded alginate nanocarriers in hydrogels using Raman and attenuated total reflection infrared spectroscopy.

PubMed

Miloudi, Lynda; Bonnier, Franck; Bertrand, Dominique; Byrne, Hugh J; Perse, Xavier; Chourpa, Igor; Munnier, Emilie

2017-07-01

Core-shell nanocarriers are increasingly being adapted in cosmetic and dermatological fields, aiming to provide an increased penetration of the active pharmaceutical or cosmetic ingredients (API and ACI) through the skin. In the final form, the nanocarriers (NC) are usually prepared in hydrogels, conferring desired viscous properties for topical application. Combined with the high chemical complexity of the encapsulating system itself, involving numerous ingredients to form a stable core and quantifying the NC and/or the encapsulated active without labor-intensive and destructive methods remains challenging. In this respect, the specific molecular fingerprint obtained from vibrational spectroscopy analysis could unambiguously overcome current obstacles in the development of fast and cost-effective quality control tools for NC-based products. The present study demonstrates the feasibility to deliver accurate quantification of the concentrations of curcumin (ACI)-loaded alginate nanocarriers in hydrogel matrices, coupling partial least square regression (PLSR) to infrared (IR) absorption and Raman spectroscopic analyses. With respective root mean square errors of 0.1469 ± 0.0175% w/w and 0.4462 ± 0.0631% w/w, both approaches offer acceptable precision. Further investigation of the PLSR results allowed to highlight the different selectivity of each approach, indicating only IR analysis delivers direct monitoring of the NC through the quantification of the Labrafac®, the main NC ingredient. Raman analyses are rather dominated by the contribution of the ACI which opens numerous perspectives to quantify the active molecules without interferences from the complex core-shell encapsulating systems thus positioning the technique as a powerful analytical tool for industrial screening of cosmetic and pharmaceutical products. Graphical abstract Quantitative analysis of encapuslated active molecules in hydrogel-based samples by means of infrared and Raman spectroscopy.

Insufficiency of the Kanagawa hemolytic test for detecting pathogenic Vibrio parahaemolyticus in Shanghai, China.

PubMed

Hongping, Wang; Jilun, Zhang; Ting, Jiang; Yixi, Bao; Xiaoming, Zhou

2011-01-01

We evaluated the Kanagawa hemolytic test and tdh gene test for accuracy in identifying pathogenic Vibrio parahaemolyticus isolates in Shanghai. One hundred and seventy-two V. parahaemolyticus isolates were collected from diarrhea patients, freshly harvested sea fish, or fresh water samples. Statistical data for the Kanagawa hemolytic test and tdh gene test were compared. There were 83.51% isolates (81/97) from patients and 22.22% isolates (10/45) from sea-fish positive for the tdh gene. However, none of 30 isolates from fresh water samples were tdh-positive. Positive Kanagawa hemolytic tests were obtained in 88.66%, 46.67%, and 76.67% of isolates, which were from patients, sea fish, and fresh water samples, respectively. Positive rates of the Kanagawa hemolytic tests and the tdh gene tests were significantly different in isolates from those 3 sources (P < 0.001). The tdh gene test showed higher specificity than the Kanagawa hemolytic test on identifying pathogenic V. parahaemolyticus isolates in Shanghai, China. Copyright © 2011 Elsevier Inc. All rights reserved.

Lipid nanocarriers and molecular targets for malaria chemotherapy.

PubMed

Jain, Kunal; Sood, Sumeet; Gowthamarajan, Kuppusamy

2014-03-01

Malaria is the most serious tropical disease of humankind and a cause of much debilitation and morbidity throughout the world especially in endemic areas like India and Africa. The development of drug resistance may be due to insufficient drug concentration in presence of high parasite load. In addition, the present pharmaceutical dosage forms are ineffective thereby necessitating the development of novel dosage forms which are effective, safe and affordable to underprivileged population of the developing world. The rapid advancement of nanotechnology has raised the possibility of using lipid nanocarriers that interact within biological environment for treatment of infectious diseases. Thus, lipid based nano-delivery systems offer a platform to formulate old and toxic antimalarial drugs thereby modifying their pharmacokinetic profile, biodistribution and targetability. Further, there is a need to develop new chemotherapy based approaches for inhibiting the parasite-specific metabolic pathways. The present review highlights the advances in lipid nanocarriers and putative molecular targets for antimalarial chemotherapy.

Nanocarrier for poorly water-soluble anticancer drugs--barriers of translation and solutions.

PubMed

Narvekar, Mayuri; Xue, Hui Yi; Eoh, June Young; Wong, Ho Lun

2014-08-01

Many existing chemotherapeutic drugs, repurposed drugs and newly developed small-molecule anticancer compounds have high lipophilicity and low water-solubility. Currently, these poorly water-soluble anticancer drugs (PWSAD) are generally solubilized using high concentrations of surfactants and co-solvents, which frequently lead to adverse side effects. In recent years, researchers have been actively exploring the use of nanotechnology as an alternative to the solvent-based drug solubilization approach. Several classes of nanocarrier systems (lipid-based, polymer-based and albumin-based) are widely studied for encapsulation and delivery of the existing and new PWSAD. These nanocarriers were also shown to offer several additional advantages such as enhanced tumour accumulation, reduced systemic toxicity and improved therapeutic effectiveness. In this article, the recent nanotechnological advances in PWSAD delivery will be reviewed. The barriers commonly encountered in the development of PWSAD nanoformulations (e.g. formulation issues and nanotoxicity issues) and the strategies to overcome these barriers will also be discussed. It is our goal to provide the pharmaceutical scientists and clinicians with more in-depth information about the nanodelivery approach, thus, more efficacious and safe PWSAD nanoformulations can be developed with improved translational success.

[Antiphospholipid syndrome with autoimmune hemolytic anemia which mimics thrombotic thrombocytopenic purpura].

PubMed

Karasawa, Naoki; Taniguchi, Yasuhiro; Hidaka, Tomonori; Katayose, Keiko; Kameda, Takuro; Side, Kotaro; Shimoda, Haruko; Nagata, Kenji; Kubuki, Yoko; Matsunaga, Takuya; Shimoda, Kazuya

2010-04-01

A 67-year-old woman was admitted to the hospital for lethargy, fever, hemolytic anemia, thrombocytopenia, and consciousness disturbance. Direct Coombs test was positive, and anti-cardiolipin beta2-glycoprotein I antibody was detected. She was diagnosed with antiphospholipid syndrome complicated with autoimmune hemolytic anemia (AIHA). She demonstrated variable consciousness disturbance, inability to distinguish right from left, dysgraphia and dyscalculia. Multiple cerebral infarctions, especially dominant cerebral hemisphere infarctions, were observed on magnetic resonance imaging. A ventilation-perfusion scan demonstrated the presence of a ventilation-perfusion mismatch in both lung fields, and multiple veinous embolisms in the right femoral, bilateral the great saphenous and popliteal veins. Therefore, pulmonary embolism and thrombophlebitis were diagnosed. Based on these findings, it was necessary to distinguish this diagnosis from thrombotic thrombocytopenic purpura (TTP). As ADAMTS-13 activity was within the normal range, TTP was denied. Thereafter, the patient was treated with 1 mg/kg of prednisolone for AIHA, 3 mg of warfarin, and 3500 units of low-molecular-weight heparin for thrombosis, and her condition improved.

Engineered, thermoresponsive, magnetic nanocarriers of oligo(ethylene glycol)-methacrylate-based biopolymers

NASA Astrophysics Data System (ADS)

McCallister, Thomas; Gidney, Elwood; Adams, Devin; Diercks, David R.; Ghosh, Santaneel

2014-11-01

Engineered magnetic nanocarriers offer attractive options for implementing novel therapeutic solutions in biomedical research; however lack of biocompatibility and external tunability have prevented a biomedical breakthrough. Here we report multifunctional, magnetic nanospheres with tailored size, volumetric transition range, and magnetic properties based on biocompatible, thermo-responsive oligo(ethylene glycol) methacrylate biopolymers. Precise control of the nanosphere size in the range 100-300 nm, coupled with a higher and broader volumetric transition range (32-42 °C), is ideal for various biomedical applications. More importantly, super-paramagnetic behavior of the nanocarriers, even after polymer shell shrinkage, indicates stable and easily controllable loss mechanisms under exposure to an ac magnetic field.

A comparison between PLGA-PEG and NIPAAm-MAA nanocarriers in curcumin delivery for hTERT silencing in lung cancer cell line.

PubMed

Roointan, A; Sharifi-Rad, M; Badrzadeh, F; Sharifi-Rad, J

2016-08-29

Lung cancer is the most common cancer among men. Since the main reason of cancer cells immortality is telomerase activity, targeting of such enzyme can be a promising approach in cancer therapy. Curcumin is a safe and efficient anticancer agent in this context, but its applications in cancer therapy are limited because of its hydrophobic structure and low solubility in water. Today, using nanocarriers for delivery of such anticancer agents is a well performed method. Here, we developed and compared the efficiency of two nanocarriers (PLGA-PEG and NIPAAm-MAA) in delivery of curcumin and also in levels of hTERT silencing in lung cancer cell line (calu-6). Scanning electron microscopy, MTT assays and real-time PCR were used for imaging, cytotoxicity testing and measuring the expression levels of hTERT after treatment of cells with different concentrations of free curcumin and curcumin loaded nanocarriers. The MTT results demonstrated that the IC50 values of curcumin loaded nanocarriers were in lower concentrations than free curcumin. The hTERT expression levels were decreased by curcumin loaded PLGA-PEG more than curcumin loaded NIPAAm-MAA and free curcumin. Our results showed that the curcumin loaded PLGA-PEG can be a useful nano based carrier for delivery of anti-cancer agents such as curcumin to fight lung cancer.

Development and characterization of morin hydrate-loaded micellar nanocarriers for the effective management of Alzheimer's disease.

PubMed

Singh, Manpreet; Thakur, Vandana; Deshmukh, Rahul; Sharma, Amit; Rathore, M S; Kumar, Ajay; Mishra, Neeraj

2018-03-01

The aim of this study was to prepare and characterise oral delivery of morin hydrate-loaded micellar nanocarriers using Pluronic P127 and Pluronic F123 for the effective management of Alzheimer's disease. After administration of formulation brain and blood drug concentration were found to be highest for optimised morin hydrate-loaded micellar nanocarriers as compared to plain morin hydrate. Significant (p < 0.05) reduction in assessed pharmacodynamic parameters was observed after administration of morin hydrate-loaded micellar nanocarriers as compared to disease control group. Chronic treatment with morin-loaded micelles significantly increased the memory in AlCl 3 induced Alzheimer's disease in Wistar rats.

A COMPARATIVE METHOD FOR TESTING THE ENZYMES OF LIVING HEMOLYTIC STREPTOCOCCI

PubMed Central

Thompson, William P.; Meleney, Frank L.

1924-01-01

1. A method is presented for the quantitative comparison under various conditions of the activity of the lipolytic enzyme of the hemolytic steptococcus. The speed of acid production as shown in the color change from pH 8.0 to 7.2, when the living streptococcus is suspended in association with ethyl butyrate, is considered to be indicative of the amount of ferment elaborated by the organism. 2. The lipolytic action is a function of living, actively growing organisms such as are present in 4 to 8 hour cultures. 3. The speed of the lipolytic action is approximately in linear proportion to the concentration of the organisms. 4. The lipolytic action is most rapid at 37.5°C., slower at 50°, and absent at 62°. 5. The organisms are partially destroyed and the lipolytic action is markedly delayed by previous heating to 55°C. for 10 minutes. Both the organisms and the lipolytic activity are completely destroyed by continued contact with this temperature for 30 minutes. 6. Increasing the virulence of the organism for rabbits by repeated animal passage does not increase the lipolytic action. 7. The predilection of the hemolytic streptococcus for the subcutaneous fat in local streptococcus infection associated with extensive superficial gangrene cannot be explained on the basis of an increase of lipolytic ferment in the organisms recovered from these cases over that of heterologous strains of streptococci. PMID:19868912

Delivery of acid sphingomyelinase in normal and niemann-pick disease mice using intercellular adhesion molecule-1-targeted polymer nanocarriers.

PubMed

Garnacho, Carmen; Dhami, Rajwinder; Simone, Eric; Dziubla, Thomas; Leferovich, John; Schuchman, Edward H; Muzykantov, Vladimir; Muro, Silvia

2008-05-01

Type B Niemann-Pick disease (NPD) is a multiorgan system disorder caused by a genetic deficiency of acid sphingomyelinase (ASM), for which lung is an important and challenging therapeutic target. In this study, we designed and evaluated new delivery vehicles for enzyme replacement therapy of type B NPD, consisting of polystyrene and poly(lactic-coglycolic) acid polymer nanocarriers targeted to intercellular adhesion molecule (ICAM)-1, an endothelial surface protein up-regulated in many pathologies, including type B NPD. Real-time vascular imaging using intravital microscopy and postmortem imaging of mouse organs showed rapid, uniform, and efficient binding of fluorescently labeled ICAM-1-targeted ASM nanocarriers (anti-ICAM/ASM nanocarriers) to endothelium after i.v. injection in mice. Fluorescence microscopy of lung alveoli actin, tissue histology, and 125I-albumin blood-to-lung transport showed that anti-ICAM nanocarriers cause neither detectable lung injury, nor abnormal vascular permeability in animals. Radioisotope tracing showed rapid disappearance from the circulation and enhanced accumulation of anti-ICAM/125I-ASM nanocarriers over the nontargeted naked enzyme in kidney, heart, liver, spleen, and primarily lung, both in wild-type and ASM knockout mice. These data demonstrate that ICAM-1-targeted nanocarriers may enhance enzyme replacement therapy for type B NPD and perhaps other lysosomal storage disorders.

Carbohydrate coated, folate functionalized colloidal graphene as a nanocarrier for both hydrophobic and hydrophilic drugs.

PubMed

Maity, Amit Ranjan; Chakraborty, Atanu; Mondal, Avijit; Jana, Nikhil R

2014-03-07

Although graphene based drug delivery has gained significant recent interest, the synthesis of colloidal graphene based nanocarriers with high drug loading capacities and with targeting ligands at the outer surface is a challenging issue. We have synthesized carbohydrate coated and folate functionalized colloidal graphene which can be used as a nanocarrier for a wide variety of hydrophobic and hydrophilic drugs. The synthesized colloidal graphene is loaded with paclitaxol, camptothecin, doxorubicin, curcumin and used for their targeted delivery to cancer cells. We demonstrate that this drug loaded functional graphene nanocarrier can successfully deliver drugs into target cells and offers an enhanced therapeutic performance. The reported approach can be extended to the cellular delivery of other hydrophobic and hydrophilic drugs and the simultaneous delivery of multiple drugs.

Rational design for multifunctional non-liposomal lipid-based nanocarriers for cancer management: theory to practice

PubMed Central

2013-01-01

Nanomedicines have gained more and more attention in cancer therapy thanks to their ability to enhance the tumour accumulation and the intracellular uptake of drugs while reducing their inactivation and toxicity. In parallel, nanocarriers have been successfully employed as diagnostic tools increasing imaging resolution holding great promises both in preclinical research and in clinical settings. Lipid-based nanocarriers are a class of biocompatible and biodegradable vehicles that provide advanced delivery of therapeutic and imaging agents, improving pharmacokinetic profile and safety. One of most promising engineering challenges is the design of innovative and versatile multifunctional targeted nanotechnologies for cancer treatment and diagnosis. This review aims to highlight rational approaches to design multifunctional non liposomal lipid-based nanocarriers providing an update of literature in this field. PMID:24564841

Specific targeting and noninvasive magnetic resonance imaging of an asthma biomarker in the lung using polyethylene glycol functionalized magnetic nanocarriers.

PubMed

Al Faraj, Achraf; Shaik, Asma Sultana; Afzal, Sibtain; Al-Muhsen, Saleh; Halwani, Rabih

2016-05-01

Simultaneous inhibition of IL4 and IL13 via the common receptor chain IL4Rα to block adequately their biologic effects presents a promising therapeutic approach to give the additional relief required for asthma patients. In this study, superparamagnetic iron oxide nanoparticles were conjugated with anti-IL4Rα blocking antibodies via polyethylene glycol (PEG) polymers. The delivery of these blocking antibodies to the inflammatory sites in the lung via the developed nanocarriers was assessed using noninvasive free-breathing pulmonary MRI. Biocompatibility assays confirmed the safety of the developed nanocarriers for pre-clinical investigations. For all the investigated formulations, nanocarriers were found to be very stable at neutral pH. However, the stability noticeably decreased with the PEG length in acidic environment and thus the loaded antibodies were preferentially released. Immunofluorescence and fluorimetry assays confirmed the binding of the nanocarriers to the IL4Rα asthma biomarker. Pulmonary MRI performed using an ultra-short echo time sequence allowed simultaneous noninvasive monitoring of inflammatory responses induced by ovalbumin challenge and tracking of the developed nanocarriers, which were found to colocalize with the inflammatory sites in the lung. Targeting of the developed nanocarriers to areas rich in IL4Rα positive inflammatory cells was confirmed using histological and flow cytometry analyses. The anti-IL4Rα-conjugated nanocarriers developed here have been confirmed to be efficient in targeting key inflammatory cells during chronic lung inflammation following intrapulmonary administration. Targeting efficiency was monitored using noninvasive MRI, allowing detection of the nanocarriers' colocalizations with the inflammatory sites in the lung of ovalbumin-challenged asthmatic mice. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Intracellular delivery of proteins by nanocarriers.

PubMed

Ray, Moumita; Lee, Yi-Wei; Scaletti, Federica; Yu, Ruijin; Rotello, Vincent M

2017-04-01

Intracellular delivery of proteins is potentially a game-changing approach for therapeutics. However, for most applications, the protein needs to access the cytosol to be effective. A wide variety of strategies have been developed for protein delivery, however access of delivered protein to the cytosol without acute cytotoxicity remains a critical issue. In this review we discuss recent trends in protein delivery using nanocarriers, focusing on the ability of these strategies to deliver protein into the cytosol.

Impact of Particle Size and Polydispersity Index on the Clinical Applications of Lipidic Nanocarrier Systems.

PubMed

Danaei, M; Dehghankhold, M; Ataei, S; Hasanzadeh Davarani, F; Javanmard, R; Dokhani, A; Khorasani, S; Mozafari, M R

2018-05-18

Lipid-based drug delivery systems, or lipidic carriers, are being extensively employed to enhance the bioavailability of poorly-soluble drugs. They have the ability to incorporate both lipophilic and hydrophilic molecules and protecting them against degradation in vitro and in vivo. There is a number of physical attributes of lipid-based nanocarriers that determine their safety, stability, efficacy, as well as their in vitro and in vivo behaviour. These include average particle size/diameter and the polydispersity index (PDI), which is an indication of their quality with respect to the size distribution. The suitability of nanocarrier formulations for a particular route of drug administration depends on their average diameter, PDI and size stability, among other parameters. Controlling and validating these parameters are of key importance for the effective clinical applications of nanocarrier formulations. This review highlights the significance of size and PDI in the successful design, formulation and development of nanosystems for pharmaceutical, nutraceutical and other applications. Liposomes, nanoliposomes, vesicular phospholipid gels, solid lipid nanoparticles, transfersomes and tocosomes are presented as frequently-used lipidic drug carriers. The advantages and limitations of a range of available analytical techniques used to characterize lipidic nanocarrier formulations are also covered.

Berberine-loaded Janus nanocarriers for magnetic field-enhanced therapy against hepatocellular carcinoma.

PubMed

Wang, Zheng; Wang, Ying-Shuai; Chang, Zhi-Min; Li, Li; Zhang, Yi; Lu, Meng-Meng; Zheng, Xiao; Li, Mingqiang; Shao, Dan; Li, Jing; Chen, Li; Dong, Wen-Fei

2017-03-01

Berberine, an bioactive isoquinolin alkaloid from traditional Chinese herbs, is considered to be a promising agent based on its remarkable activity against hepatocellular carcinoma. However, the clinical application of this nature compound had been hampered owing to its properties such as poor aqueous solubility, low gastrointestinal absorption, and reduced bioavailability. Therefore, we developed Janus magnetic mesoporous silica nanoparticles (Fe 3 O 4 -mSiO 2 NPs) consisting of a Fe 3 O 4 head for magnetic targeting and a mesoporous SiO 2 body for berberine delivery. A pH-sensitive group was introduced on the surface of mesoporous silica for berberine loading to develop a tumor microenvironment-responsive nanocarrier, which exhibited uniform morphology, good superparamagnetic properties, high drug-loading amounts, superior endocytic ability, and low cytotoxicity. Berberine-loaded Fe 3 O 4 -mSiO 2 NPs exerted extraordinarily high specificity for hepatocellular carcinoma cells, which was due to the pH-responsive berberine release, as well as higher endocytosis capacity in hepatocellular carcinoma cells rather than normal liver cells. More importantly, an external magnetic field could significantly improve antitumor activity of Ber-loaded Fe 3 O 4 -mSiO 2 NPs through enhancing berberine internalization. Taken together, our results suggest that Janus nanocarriers driven by the magnetic field may provide an effective and safe way to facilitate clinical use of berberine against hepatocellular carcinoma. © 2016 John Wiley & Sons A/S.

Thermodynamic and Kinetic Aspects Involved in the Development of Nanocarriers and Drug Delivery Systems Based on Cationic Biopolymers.

PubMed

Bianco, Ismael D; Alasino, Roxana V; Leonhard, Victoria; Beltramo, Dante M

2016-01-01

During the last years we have seen an increasing number of reports describing new properties and potential applications of cationic polymers and derived nanostructures. This review gives a summary of their applications in drug delivery, the preparation methods for nano and microstructures and will attempt to give a glimpse on how their structure, chemical composition and properties may be affected or modulated as to make them suitable for an intended application as drug delivery nanocarriers. The compositional complexity with the existence of several reacting groups makes cationic nanostructures critically sensitive to the contribution of thermodynamic and kinetic parameters in the determination of the type and stability of a particular structure and its ability to respond to changes in environmental conditions in the right time frame. Curiously, and contrarily to what could be expected, despite the fact that cationic polymers can form strong electrostatic interactions the contribution of the entropic component has been often found to be very important for their association with negatively charged supramolecular structures. Some general considerations indicate that when considering a complex multimolecular system like a nanocarrier containing an active ingredient it is frequently possible to find conditions under which enthalpic and entropic contributions are compensated leading to stable structures with a marginal thermodynamic stability (free energy change close to zero) which make them able to respond relatively fast to changes in the environmental conditions and therefore suitable for the design of smart drug delivery systems. Like with other nanocarriers, it should always be kept in mind that the properties of cationic nanocarriers will depend not only on their chemical composition but also on the properties of the structures formed by them.

Association of Alpha Tocopherol and Ag Sulfadiazine Chitosan Oleate Nanocarriers in Bioactive Dressings Supporting Platelet Lysate Application to Skin Wounds.

PubMed

Bonferoni, Maria Cristina; Sandri, Giuseppina; Rossi, Silvia; Dellera, Eleonora; Invernizzi, Alessandro; Boselli, Cinzia; Cornaglia, Antonia Icaro; Del Fante, Claudia; Perotti, Cesare; Vigani, Barbara; Riva, Federica; Caramella, Carla; Ferrari, Franca

2018-02-09

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds.

Association of Alpha Tocopherol and Ag Sulfadiazine Chitosan Oleate Nanocarriers in Bioactive Dressings Supporting Platelet Lysate Application to Skin Wounds

PubMed Central

Bonferoni, Maria Cristina; Dellera, Eleonora; Invernizzi, Alessandro; Cornaglia, Antonia Icaro; Perotti, Cesare; Vigani, Barbara; Caramella, Carla; Ferrari, Franca

2018-01-01

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds. PMID:29425164

Targeted Mesoporous Silica Nanocarriers in Oncology.

PubMed

Baeza, Alejandro; Vallet-Regi, Maria

2018-02-08

Cancer is one of the major leading causes of death worldwide and its prevalence will be higher in the coming years due to the progressive aging of the population. The development of nanocarriers in oncology has provided a new hope in the fight against this terrible disease. Among the different types of nanoparticles which have been reported in the scientific literature, mesoporous silica nanoparticles (MSNs) are very promising materials due to their inherent properties such as high loading capacity of many different drugs, excellent biocompatibility and easy functionalization. This review presents the current state of the art related to the development of mesoporous silica nanocarriers for antitumoral therapy paying special attention on targeted MSN able to selectively destroy tumoral cells, reducing the side damage in healthy ones, and the basic principles of targeting tumoral tissues and cells. MSNs constitute a promising nanomaterial for drug delivery applications in antitumoral therapy as a consequence of its unique properties such as excellent biocompatibility, high loading capacity, robustness, easy production and existence of multiple strategies for their functionalization with a myriad of bio-organic moieties. In the coming years, the clever application of this material would provide novel alternatives for the treatment of this complex disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Tailored dendritic core-multishell nanocarriers for efficient dermal drug delivery: A systematic top-down approach from synthesis to preclinical testing.

PubMed

Hönzke, Stefan; Gerecke, Christian; Elpelt, Anja; Zhang, Nan; Unbehauen, Michael; Kral, Vivian; Fleige, Emanuel; Paulus, Florian; Haag, Rainer; Schäfer-Korting, Monika; Kleuser, Burkhard; Hedtrich, Sarah

2016-11-28

Drug loaded dendritic core-multishell (CMS) nanocarriers are of especial interest for the treatment of skin diseases, owing to their striking dermal delivery efficiencies following topical applications. CMS nanocarriers are composed of a polyglycerol core, connected by amide-bonds to an inner alkyl shell and an outer methoxy poly(ethylene glycol) shell. Since topically applied nanocarriers are subjected to biodegradation, the application of conventional amide-based CMS nanocarriers (10-A-18-350) has been limited by the potential production of toxic polyglycerol amines. To circumvent this issue, three tailored ester-based CMS nanocarriers (10-E-12-350, 10-E-15-350, 10-E-18-350) of varying inner alkyl chain length were synthesized and comprehensively characterized in terms of particle size, drug loading, biodegradation and dermal drug delivery efficiency. Dexamethasone (DXM), a potent drug widely used for the treatment of inflammatory skin diseases, was chosen as a therapeutically relevant test compound for the present study. Ester- and amide-based CMS nanocarriers delivered DXM more efficiently into human skin than a commercially available DXM cream. Subsequent in vitro and in vivo toxicity studies identified CMS (10-E-15-350) as the most biocompatible carrier system. The anti-inflammatory potency of DXM-loaded CMS (10-E-15-350) nanocarriers was assessed in TNFα supplemented skin models, where a significant reduction of the pro-inflammatory cytokine IL-8 was seen, with markedly greater efficacy than commercial DXM cream. In summary, we report the rational design and characterization of tailored, biodegradable, ester-based CMS nanocarriers, and their subsequent stepwise screening for biocompatibility, dermal delivery efficiency and therapeutic efficacy in a top-down approach yielding the best carrier system for topical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Rasburicase-induced Hemolytic Anemia in an Adolescent With Unknown Glucose-6-Phosphate Dehydrogenase Deficiency.

PubMed

Akande, Manzilat; Audino, Anthony N; Tobias, Joseph D

2017-01-01

Rasburicase, used in the prevention and treatment of tumor lysis syndrome (TLS), may cause hemolytic anemia and methemoglobinemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Although routine screening for G6PD deficiency has been recommended, given the turnaround time for test results and the urgency to treat TLS, such screening may not be feasible. We report a case of rasburicase-induced hemolytic anemia without methemoglobinemia in an adolescent with T-cell lymphoblastic lymphoma, TLS, and previously unrecognized G6PD deficiency. Previous reports of hemolytic anemia with rasburicase are reviewed, mechanisms discussed, and preventative strategies presented.

DNA Nanocarriers for Systemic Administration: Characterization and In Vivo Bioimaging in Healthy Mice

PubMed Central

David, Stephanie; Passirani, Catherine; Carmoy, Nathalie; Morille, Marie; Mevel, Mathieu; Chatin, Benoit; Benoit, Jean-Pierre; Montier, Tristan; Pitard, Bruno

2013-01-01

We hereby present different DNA nanocarriers consisting of new multimodular systems (MMS), containing the cationic lipid dioleylaminesuccinylparomomycin (DNA MMS DOSP), or bis (guanidinium)-tren-cholesterol (DNA MMS BGTC), and DNA lipid nanocapsules (DNA LNCs). Active targeting of the asialoglycoprotein receptor (ASGP-R) using galactose as a ligand for DNA MMS (GAL DNA MMS) and passive targeting using a polyethylene glycol coating for DNA LNCs (PEG DNA LNCs) should improve the properties of these DNA nanocarriers. All systems were characterized via physicochemical methods and the DNA payload of DNA LNCs was quantified for the first time. Afterwards, their biodistribution in healthy mice was analyzed after encapsulation of a fluorescent dye via in vivo biofluorescence imaging (BFI), revealing various distribution profiles depending on the cationic lipid used and their surface characteristics. Furthermore, the two vectors with the best prolonged circulation profile were administered twice in healthy mice revealing that the new DNA MMS DOSP vectors showed no toxicity and the same distribution profile for both injections, contrary to PEG DNA LNCs which showed a rapid clearance after the second injection, certainly due to the accelerated blood clearance phenomenon. PMID:23299832

Magnetically guided central nervous system delivery and toxicity evaluation of magneto-electric nanocarriers.

PubMed

Kaushik, Ajeet; Jayant, Rahul D; Nikkhah-Moshaie, Roozbeh; Bhardwaj, Vinay; Roy, Upal; Huang, Zaohua; Ruiz, Ariel; Yndart, Adriana; Atluri, Venkata; El-Hage, Nazira; Khalili, Kamel; Nair, Madhavan

2016-05-04

Least component-based delivery of drug-tagged-nanocarriers across blood-brain-barriers (BBB) will allow site-specific and on-demand release of therapeutics to prevent CNS diseases. We developed a non-invasive magnetically guided delivery of magneto-electric nanocarriers (MENCs), ~20 nm, 10 mg/kg, across BBB in C57Bl/J mice. Delivered MENCs were uniformly distributed inside the brain, and were non-toxic to brain and other major organs, such as kidney, lung, liver, and spleen, and did not affect hepatic, kidney and neurobehavioral functioning.

Magnetically guided central nervous system delivery and toxicity evaluation of magneto-electric nanocarriers

PubMed Central

Kaushik, Ajeet; Jayant, Rahul D.; Nikkhah-Moshaie, Roozbeh; Bhardwaj, Vinay; Roy, Upal; Huang, Zaohua; Ruiz, Ariel; Yndart, Adriana; Atluri, Venkata; El-Hage, Nazira; Khalili, Kamel; Nair, Madhavan

2016-01-01

Least component-based delivery of drug-tagged-nanocarriers across blood-brain-barriers (BBB) will allow site-specific and on-demand release of therapeutics to prevent CNS diseases. We developed a non-invasive magnetically guided delivery of magneto-electric nanocarriers (MENCs), ~20 nm, 10 mg/kg, across BBB in C57Bl/J mice. Delivered MENCs were uniformly distributed inside the brain, and were non-toxic to brain and other major organs, such as kidney, lung, liver, and spleen, and did not affect hepatic, kidney and neurobehavioral functioning. PMID:27143580

Folate Conjugated Hybrid Nanocarrier for Targeted Letrozole Delivery in Breast Cancer Treatment.

PubMed

Hemati Azandaryani, Abbas; Kashanian, Soheila; Derakhshandeh, Katayoun

2017-12-01

Letrozole as a steroidal anticancer drug with hydrophobic nature is usually administrated by oral route for patient treatment and the injectable formulation for this drug has not still been reported. In this study, a new letrozole incorporated folate-conjugated polymer - lipid hybrid nanoparticles - is introduced for cancer treatment. Nanoparticles were fabricated via modified oil in water ionic gelation method using optimization parameters and then were coupled to folic acid using carbodiimide activation. The physicochemical characterization in vitro drug release, cytotoxicity, and then ex vivo study of obtained carrier was investigated. Both thermal and crystallography studies proved the amorphous loading of drug in the nanocarrier. The cytotoxicity investigation with an average IC 50 value of 79 ± 2.40 nM proved the efficiency of the coupled folic acid carrier for the intracellular uptake of letrozole on the breast cancer line. Ex vivo, the study proved the positive effect of the letrozole entrapment on the drug bioavailability. The obtained targeted nanocarrier could overcome the limitations associated with the LTZ as a potent non-steroidal drug. Both the entrapment and therapeutic efficiency of letrozole in the amphiphilic carrier were increased using the lipid nanoparticles and the surface modification, respectively.

Effective co-delivery of doxorubicin and dasatinib using a PEG-Fmoc nanocarrier for combination cancer chemotherapy.

PubMed

Zhang, Peng; Li, Jiang; Ghazwani, Mohammed; Zhao, Wenchen; Huang, Yixian; Zhang, Xiaolan; Venkataramanan, Raman; Li, Song

2015-10-01

A simple PEGylated peptidic nanocarrier, PEG5000-lysyl-(α-Fmoc-ε-Cbz-lysine)2 (PLFCL), was developed for effective co-delivery of doxorubicin (DOX) and dasatinib (DAS) for combination chemotherapy. Significant synergy of DOX and DAS in inhibition of cancer cell proliferation was demonstrated in various types of cancer cells, including breast, prostate, and colon cancers. Co-encapsulation of the two agents was facilitated by incorporation of 9-Fluorenylmethoxycarbonyl (Fmoc) and carboxybenzyl (Cbz) groups into a nanocarrier for effective carrier-drug interactions. Spherical nanomicelles with a small size of ∼30 nm were self-assembled by PLFCL. Strong carrier/drug intermolecular π-π stacking was demonstrated in fluorescence quenching and UV absorption. Fluorescence study showed more effective accumulation of DOX in nuclei of cancer cells following treatment with DOX&DAS/PLFCL in comparison with cells treated with DOX/PLFCL. DOX&DAS/PLFCL micelles were also more effective than other treatments in inhibiting the proliferation and migration of cultured cancer cells. Finally, a superior anti-tumor activity was demonstrated with DOX&DAS/PLFCL. A tumor growth inhibition rate of 95% was achieved at a respective dose of 5 mg/kg for DOX and DAS in a murine breast cancer model. Our nanocarrier may represent a simple and effective system that could facilitate clinical translation of this promising multi-agent regimen in combination chemotherapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Photoinduced PEG deshielding from ROS-sensitive linkage-bridged block copolymer-based nanocarriers for on-demand drug delivery.

PubMed

Li, Jie; Sun, Chunyang; Tao, Wei; Cao, Ziyang; Qian, Haisheng; Yang, Xianzhu; Wang, Jun

2018-07-01

Controlling poly(ethylene glycol) (PEG) shielding/deshielding at the desired site of action exhibits great advantages for nanocarrier-based on-demand drug delivery in vivo. However, the current PEG deshielding strategies were mainly designed for anticancer drug delivery; even so, their applications are also limited by tumor heterogeneity. As a proof-of-concept, we explored a photoinduced PEG deshielding nanocarrier TK-NP Ce6&PTX to circumvent the aforementioned challenge. The TK-NP Ce6&PTX encapsulating chlorin e6 (Ce6) and paclitaxel (PTX) was self-assembled from an innovative thioketal (TK) linkage-bridged diblock copolymer of PEG with poly(d,l-lactic acid) (PEG-TK-PLA). We demonstrated that the high PEGylation of TK-NP Ce6&PTX in blood helps the nanocarrier efficiently avoid rapid clearance and consequently prolongs its circulation time. At the desired site (tumor), 660-nm red light irradiation led to ROS generation in situ, which readily cleaved the TK linkage, resulting in PEG deshielding. Such photoinduced PEG deshielding at the desired site significantly enhances the cellular uptake of the nanocarriers, achieving on-demand drug delivery and superior therapeutic efficacy. More importantly, this strategy of photoinducing PEG deshielding of nanocarriers could potentially extend to a variety of therapeutic agents beyond anticancer drugs for on-demand delivery. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Bacillus thuringiensis cyt Genes for Hemolytic Endotoxins Constitute a Gene Family

PubMed Central

Guerchicoff, Alejandra; Delécluse, Armelle; Rubinstein, Clara P.

2001-01-01

In the same way that cry genes, coding for larvicidal delta endotoxins, constitute a large and diverse gene family, the cyt genes for hemolytic toxins seem to compose another set of highly related genes in Bacillus thuringiensis. Although the occurrence of Cyt hemolytic factors in B. thuringiensis has been typically associated with mosquitocidal strains, we have recently shown that cyt genes are also present in strains with different pathotypes; this is the case for the morrisoni subspecies, which includes strains biologically active against dipteran, lepidopteran, and coleopteran larvae. In addition, while one Cyt type of protein has been described in all of the mosquitocidal strains studied so far, the present study confirms that at least two Cyt toxins coexist in the more toxic antidipteran strains, such as B. thuringiensis subsp. israelensis and subsp. morrisoni PG14, and that this could also be the case for many others. In fact, PCR screening and Western blot analysis of 50 B. thuringiensis strains revealed that cyt2-related genes are present in all strains with known antidipteran activity, as well as in some others with different or unknown host ranges. Partial DNA sequences for several of these genes were determined, and protein sequence alignments revealed a high degree of conservation of the structural domains. These findings point to an important biological role for Cyt toxins in the final in vivo toxic activity of many B. thuringiensis strains. PMID:11229896

Near-infrared optical imaging of nucleic acid nanocarriers in vivo.

PubMed

Rome, Claire; Gravier, Julien; Morille, Marie; Divita, Gilles; Bolcato-Bellemin, Anne-Laure; Josserand, Véronique; Coll, Jean-Luc

2013-01-01

Noninvasive, real-time optical imaging methods are well suited to follow the in vivo distribution of nucleic acid nanocarriers, their dissociation, and the resulting gene expression or inhibition. Indeed, most small animal imaging devices perform bioluminescence and fluorescence measurements without moving the animal, allowing a simple, rapid, and cost-effective method of investigation of several parameters at a time, in longitudinal experiments that can last for days or weeks.Here we help the reader in choosing adapted near-infrared (NIR) fluorophores or pairs of fluorophores for Förster resonance energy transfer assays, imaging of reporter genes, as well as nanocarriers for in vivo gene and siRNA delivery. In addition, we present the labeling methods of these macromolecules and of their payload and the protocols to detect them using bioluminescence and NIR fluorescence imaging in mice.

SAXS Study of Sterically Stabilized Lipid Nanocarriers Functionalized by DNA

NASA Astrophysics Data System (ADS)

Angelov, Borislav; Angelova, Angelina; Filippov, Sergey; Karlsson, Göran; Terrill, Nick; Lesieur, Sylviane; Štěpánek, Petr

2012-03-01

The structure of novel spontaneously self-assembled plasmid DNA/lipid complexes is investigated by means of synchrotron radiation small-angle X-ray scattering (SAXS) and Cryo-TEM imaging. Liquid crystalline (LC) hydrated lipid systems are prepared using the non-ionic lipids monoolein and DOPE-PEG2000 and the cationic amphiphile CTAB. The employed plasmid DNA (pDNA) is encoding for the human protein brain-derived neurotrophic factor (BDNF). A coexistence of nanoparticulate objects with different LC inner organizations is established. A transition from bicontinuous membrane sponges, cubosome intermediates and unilamelar liposomes to multilamellar vesicles, functionalized by pDNA, is favoured upon binding and compaction of pBDNF onto the cationic PEGylated lipid nanocarriers. The obtained sterically stabilized multicompartment nanoobjects, with confined supercoiled plasmid DNA (pBDNF), are important in the context of multicompartment lipid nanocarriers of interest for gene therapy of neurodegenerative diseases.

Near-infrared optical imaging of nucleic acid nanocarriers in vivo

PubMed Central

Rome, Claire; Gravier, Julien; Morille, Marie; Divita, Gilles; Bolcato-Bellemin, Anne-Laure; Josserand, Véronique; Coll, Jean-Luc

2013-01-01

Summary Non-invasive, real time optical imaging methods are particularly well suited for the in vivo follow up of the distribution of nucleic acids nanocarriers, their dissociation and finally the resulting gene expression or inhibition. Indeed, most small animal imaging devices are performing bioluminescence and fluorescence measurements without moving the animal, allowing a simple, rapid and cost effective method of investigation of several parameters at a time, in longitudinal experiments that can last for days or weeks. Here we propose to help the reader choosing adapted near-infrared (NIR) fluorophores or pairs of fluorophores for FRET assays, reporter genes as well as nanocarriers for in vivo gene and siRNA delivery. In addition, we present the labeling methods of these macromolecules, and of their payload and the protocols to detect them using bioluminescence and NIR fluorescence imaging in mice. PMID:23070763

Interference of alpha-hemolytic streptococci isolated from tonsillar surface on beta-hemolytic streptococci (Streptococcus pyogenes)--a methodological study.

PubMed

Grahn, E; Holm, S E; Ekedahl, C; Roos, K

1983-07-01

The interference between alpha-streptococcal strains obtained from patients with repeated tonsillitis and a collection of group A streptococcal strains were studied. For this purpose three in vitro methods were designed and compared. The results obtained by a simple plating technique suitable for screening purposes were found to correlate well with those using more laborious techniques. In a limited scale some of the alpha- and beta-streptococcal combinations were tested under in vivo conditions using a tissue cage model allowing repeated sampling. In most instances agreement between the results of the in vitro and in vivo methods was registered. Several alpha-strains having inhibitory capacity to the majority of a collection of group A streptococci belonging to different serotypes were found, but also alpha-strains with an inhibitory activity restricted to few group A isolates within a certain serotype. Also beta-streptococcal strains with growth inhibiting activity towards some alpha-strains were found. As the methods were chosen to eliminate many of the unspecific inhibitory factors and the beta-hemolytic test strains showed a pattern of inhibition that varied for each of the reference alpha-strains the activity is most likely attributed to bacteriocin-like substances.

Merging high doxorubicin loading with pronounced magnetic response and bio-repellent properties in hybrid drug nanocarriers.

PubMed

Bakandritsos, Aristides; Papagiannopoulos, Aristeidis; Anagnostou, Eleni N; Avgoustakis, Konstantinos; Zboril, Radek; Pispas, Stergios; Tucek, Jiri; Ryukhtin, Vasyl; Bouropoulos, Nikolaos; Kolokithas-Ntoukas, Argiris; Steriotis, Theodore A; Keiderling, Uwe; Winnefeld, Frank

2012-08-06

Hybrid magnetic drug nanocarriers are prepared via a self-assembly process of poly(methacrylic acid)-graft-poly(ethyleneglycol methacrylate) (p(MAA-g-EGMA)) on growing iron oxide nanocrystallites. The nanocarriers successfully merge together bio-repellent properties, pronounced magnetic response, and high loading capacity for the potent anticancer drug doxorubicin (adriamicin), in a manner not observed before in such hybrid colloids. High magnetic responses are accomplished by engineering the size of the magnetic nanocrystallites (∼13.5 nm) following an aqueous single-ferrous precursor route, and through adjustment of the number of cores in each colloidal assembly. Complementing conventional magnetometry, the magnetic response of the nanocarriers is evaluated by magnetophoretic experiments providing insight into their internal organization and on their response to magnetic manipulation. The structural organization of the graft-copolymer, locked on the surface of the nanocrystallites, is further probed by small-angle neutron scattering on single-core colloids. Analysis showed that the MAA segments selectively populate the area around the magnetic nanocrystallites, while the poly(ethylene glycol)-grafted chains are arranged as protrusions, pointing towards the aqueous environment. These nanocarriers are screened at various pHs and in highly salted media by light scattering and electrokinetic measurements. According to the results, their stability is dramatically enhanced, as compared to uncoated nanocrystallites, owing to the presence of the external protective PEG canopy. The nanocarriers are also endowed with bio-repellent properties, as evidenced by stability assays using human blood plasma as the medium. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pathogenic Variants in Complement Genes and Risk of Atypical Hemolytic Uremic Syndrome Relapse after Eculizumab Discontinuation.

PubMed

Fakhouri, Fadi; Fila, Marc; Provôt, François; Delmas, Yahsou; Barbet, Christelle; Châtelet, Valérie; Rafat, Cédric; Cailliez, Mathilde; Hogan, Julien; Servais, Aude; Karras, Alexandre; Makdassi, Raifah; Louillet, Feriell; Coindre, Jean-Philippe; Rondeau, Eric; Loirat, Chantal; Frémeaux-Bacchi, Véronique

2017-01-06

The complement inhibitor eculizumab has dramatically improved the outcome of atypical hemolytic uremic syndrome. However, the optimal duration of eculizumab treatment in atypical hemolytic uremic syndrome remains debated. We report on the French atypical hemolytic uremic syndrome working group's first 2-year experience with eculizumab discontinuation in patients with atypical hemolytic uremic syndrome. Using the French atypical hemolytic uremic syndrome registry database, we retrospectively identified all dialysis-free patients with atypical hemolytic uremic syndrome who discontinued eculizumab between 2010 and 2014 and reviewed their relevant clinical and biologic data. The decision to discontinue eculizumab was made by the clinician in charge of the patient. All patients were closely monitored by regular urine dipsticks and blood tests. Eculizumab was rapidly (24-48 hours) restarted in case of relapse. Among 108 patients treated with eculizumab, 38 patients (nine children and 29 adults) discontinued eculizumab (median treatment duration of 17.5 months). Twenty-one patients (55%) carried novel or rare complement genes variants. Renal recovery under eculizumab was equally good in patients with and those without complement gene variants detected. After a median follow-up of 22 months, 12 patients (31%) experienced atypical hemolytic uremic syndrome relapse. Eight of 11 patients (72%) with complement factor H variants, four of eight patients (50%) with membrane cofactor protein variants, and zero of 16 patients with no rare variant detected relapsed. In relapsing patients, early reintroduction (≤48 hours) of eculizumab led to rapid (<7 days) hematologic remission and a return of serum creatinine to baseline level in a median time of 26 days. At last follow-up, renal function remained unchanged in nonrelapsing and relapsing patients compared with baseline values before eculizumab discontinuation. Pathogenic variants in complement genes were associated with higher

Identification and Characterization of Staphylococcus aureus Strains with an Incomplete Hemolytic Phenotype.

PubMed

Zhang, Haifang; Zheng, Yi; Gao, Huasheng; Xu, Ping; Wang, Min; Li, Aiqing; Miao, Minhui; Xie, Xiaofang; Deng, Yimai; Zhou, Huiqin; Du, Hong

2016-01-01

Staphylococcus aureus is a common pathogen causing both hospital and community-acquired infections. Hemolysin is one of the important virulence factors for S. aureus and causes the typical β-hemolytic phenotype which is called complete hemolytic phenotype as well. Recently, S. aureus with an incomplete hemolytic phenotype (SIHP) was isolated from clinical samples. To study the microbiologic characteristics of SIHP, the special hemolytic phenotype of SIHP was verified on the sheep blood agar plates supplied by different manufacturers. Expression of hemolysin genes hla, hlb, hlgC , and hld of SIHP was detected by qRT-PCR and it was showed that expression of hlb in SIHP was obviously increased compared to the control S. aureus strains with complete hemolytic phenotype (SCHP), while the expression of hla, hlgC , and hld in SIHP was significantly decreased. In addition, the α-hemolysin encoded by gene hla was decreased obviously in SIHP compared to SCHP by western blot. All 60 SIHP strains were identified to be the methicillin resistant S. aureus (MRSA), and moreover these SIHP strains all contains mecA gene. The virulence gene tst were all present in SIHP, and the intracellular survival ability of SIHP was much greater than that of the gene tst negative S. aureus . We also found that IL-2, IL-6, and IL-17A secreted in the supernatant of SIHP infected macrophages increased significantly compared to tst negative control strains infected ones. MLST analysis showed that all of SIHP strains were classified into ST5 clone. To our knowledge, this study firstly showed that SIHP strains are a kind of methicillin resistant strains which express β-hemolysin highly and possess a potential high virulence, and it was suggested that SIHP should be paid more attention in hospital.

Review: Milk Proteins as Nanocarrier Systems for Hydrophobic Nutraceuticals.

PubMed

Kimpel, Florian; Schmitt, Joachim J

2015-11-01

Milk proteins and milk protein aggregates are among the most important nanovehicles in food technology. Milk proteins have various functional properties that facilitate their ability to carry hydrophobic nutraceutical substances. The main functional transport properties that were examined in the reviewed studies are binding of molecules or ions, surface activity, aggregation, gelation, and interaction with other polymers. Hydrophobic binding has been investigated using caseins and isolated β-casein as well as whey proteins. Surface activity of caseins has been used to create emulsion-based carrier systems. Furthermore, caseins are able to self-assemble into micelles, which can incorporate molecules. Gelation and interaction with other polymers can be used to encapsulate molecules into protein networks. The release of transported substances mainly depends on pH and swelling behavior of the proteins. The targeted use of nanocarrier systems requires specific knowledge about the binding mechanisms between the proteins and the carried substances in a certain food matrix. © 2015 Institute of Food Technologists®

Quiescent complement in nonhuman primates during E coli Shiga toxin-induced hemolytic uremic syndrome and thrombotic microangiopathy.

PubMed

Lee, Benjamin C; Mayer, Chad L; Leibowitz, Caitlin S; Stearns-Kurosawa, D J; Kurosawa, Shinichiro

2013-08-01

Enterohemorrhagic Escherichia coli (EHEC) produce ribosome-inactivating Shiga toxins (Stx1, Stx2) responsible for development of hemolytic uremic syndrome (HUS) and acute kidney injury (AKI). Some patients show complement activation during EHEC infection, raising the possibility of therapeutic targeting of complement for relief. Our juvenile nonhuman primate (Papio baboons) models of endotoxin-free Stx challenge exhibit full spectrum HUS, including thrombocytopenia, hemolytic anemia, and AKI with glomerular thrombotic microangiopathy. There were no significant increases in soluble terminal complement complex (C5b-9) levels after challenge with lethal Stx1 (n = 6) or Stx2 (n = 5) in plasma samples from T0 to euthanasia at 49.5 to 128 hours post-challenge. d-dimer and cell injury markers (HMGB1, histones) confirmed coagulopathy and cell injury. Thus, complement activation is not required for the development of thrombotic microangiopathy and HUS induced by EHEC Shiga toxins in these preclinical models, and benefits or risks of complement inhibition should be studied further for this infection.

[Occurrence and drug-resistance of beta-hemolytic streptococci].

PubMed

Mikołajczyk, Dorota; Budzyńska, Anna; Kaczmarek, Agnieszka; Gospodarek, Eugenia

2007-01-01

The aim of this study was the analysis of drug-resistance and frequency appearance of beta-hemolytic streptococci strains which were isolated in 2003-2005 in the University Hospital at the L. Rydygier Collegium Medicum in Bydgoszcz University of Nicolaus Copernicus in Toruń. Among investigeted beta-hemolytic streptococci the most frequency isolated species was S. agalactiae. All isolates examined in our study were susceptible to penicillin, the higest rate of resistance was found for tetracycline. The rates of resistence to macrolide-lincosamide-streptogramin B (phenotyp MLS(B)) were as follows: S. agalactiae (18.7%), S. pyogenes (10.1%), group G streptococci (10.6%) and group C streptococci (8.0%). In our study we presented also a special case patient from which in investigeted period S. agalactiae was isolated twenty eight times. For ten chromosomal DNA isolated from this patient three different PFGE profiles were obtained.

Severe Hemolytic Jaundice in a Neonate with a Novel COL4A1 Mutation.

PubMed

Tomotaki, Seiichi; Mizumoto, Hiroshi; Hamabata, Takayuki; Kumakura, Akira; Shiota, Mitsutaka; Arai, Hiroshi; Haginoya, Kazuhiro; Hata, Daisuke

2016-12-01

We report our experience with a preterm infant with severe hemolytic jaundice who required exchange transfusion just after birth. The patient was negative for alloimmune hemolysis as a result of maternal-fetal blood type incompatibility, and tests for inherited defects in erythrocyte metabolism, membrane function, and hemoglobin synthesis were normal. We also performed a bone marrow examination, but could not identify the cause of hemolysis. The patient had several other complications, including porencephaly, epilepsy, elevated serum levels of creatine kinase, and persistent microscopic hematuria. Later, we detected a genetic mutation in COL4A1, which was recently found to be associated with hemolytic anemia. We therefore believe that all of the patient's clinical features, including hemolytic anemia, were due to the mutation in COL4A1. Genetic testing for COL4A1 mutations is recommended in neonates who exhibit hemolytic disease of unknown etiology, especially when other complications compatible with COL4A1-related disorders are present. Copyright © 2014. Published by Elsevier B.V.

Nanocarriers for nuclear imaging and radiotherapy of cancer.

PubMed

Mitra, Amitava; Nan, Anjan; Line, Bruce R; Ghandehari, Hamidreza

2006-01-01

Several nanoscale carriers (nanoparticles, liposomes, water-soluble polymers, micelles and dendrimers) have been developed for targeted delivery of cancer diagnostic and therapeutic agents. These carriers can selectively target cancer sites and carry large payloads, thereby improving cancer detection and therapy effectiveness. Further, the combination of newer nuclear imaging techniques providing high sensitivity and spatial resolution such as dual modality imaging with positron emission tomography/computed tomography (PET/CT) and use of nanoscale devices to carry diagnostic and therapeutic radionuclides with high target specificity can enable more accurate detection, staging and therapy planning of cancer. The successful clinical applications of radiolabeled monoclonal antibodies for cancer detection and therapy bode well for the future of nanoscale carrier systems in clinical oncology. Several radiolabeled multifunctional nanocarriers have been effective in detecting and treating cancer in animal models. Nonetheless, further preclinical, clinical and long-term toxicity studies will be required to translate this technology to the care of patients with cancer. The objective of this review is to present a brief but comprehensive overview of the various nuclear imaging techniques and the use of nanocarriers to deliver radionuclides for the diagnosis and therapy of cancer.

A hemolytic pigment of Group B Streptococcus allows bacterial penetration of human placenta

PubMed Central

Whidbey, Christopher; Harrell, Maria Isabel; Burnside, Kellie; Ngo, Lisa; Becraft, Alexis K.; Iyer, Lakshminarayan M.; Aravind, L.; Hitti, Jane

2013-01-01

Microbial infection of the amniotic fluid is a significant cause of fetal injury, preterm birth, and newborn infections. Group B Streptococcus (GBS) is an important human bacterial pathogen associated with preterm birth, fetal injury, and neonatal mortality. Although GBS has been isolated from amniotic fluid of women in preterm labor, mechanisms of in utero infection remain unknown. Previous studies indicated that GBS are unable to invade human amniotic epithelial cells (hAECs), which represent the last barrier to the amniotic cavity and fetus. We show that GBS invades hAECs and strains lacking the hemolysin repressor CovR/S accelerate amniotic barrier failure and penetrate chorioamniotic membranes in a hemolysin-dependent manner. Clinical GBS isolates obtained from women in preterm labor are hyperhemolytic and some are associated with covR/S mutations. We demonstrate for the first time that hemolytic and cytolytic activity of GBS is due to the ornithine rhamnolipid pigment and not due to a pore-forming protein toxin. Our studies emphasize the importance of the hemolytic GBS pigment in ascending infection and fetal injury. PMID:23712433

DNA nanocarriers for systemic administration: characterization and in vivo bioimaging in healthy mice.

PubMed

David, Stephanie; Passirani, Catherine; Carmoy, Nathalie; Morille, Marie; Mevel, Mathieu; Chatin, Benoit; Benoit, Jean-Pierre; Montier, Tristan; Pitard, Bruno

2013-01-08

We hereby present different DNA nanocarriers consisting of new multimodular systems (MMS), containing the cationic lipid dioleylaminesuccinylparomomycin (DNA MMS DOSP), or bis (guanidinium)-tren-cholesterol (DNA MMS BGTC), and DNA lipid nanocapsules (DNA LNCs). Active targeting of the asialoglycoprotein receptor (ASGP-R) using galactose as a ligand for DNA MMS (GAL DNA MMS) and passive targeting using a polyethylene glycol coating for DNA LNCs (PEG DNA LNCs) should improve the properties of these DNA nanocarriers. All systems were characterized via physicochemical methods and the DNA payload of DNA LNCs was quantified for the first time. Afterwards, their biodistribution in healthy mice was analyzed after encapsulation of a fluorescent dye via in vivo biofluorescence imaging (BFI), revealing various distribution profiles depending on the cationic lipid used and their surface characteristics. Furthermore, the two vectors with the best prolonged circulation profile were administered twice in healthy mice revealing that the new DNA MMS DOSP vectors showed no toxicity and the same distribution profile for both injections, contrary to PEG DNA LNCs which showed a rapid clearance after the second injection, certainly due to the accelerated blood clearance phenomenon.Molecular Therapy - Nucleic Acids (2013) 2, e64; doi:10.1038/mtna.2012.56; published online 8 January 2013.

Magnetic pH-responsive poly(methacrylic acid-co-acrylic acid)-co-polyvinylpyrrolidone magnetic nano-carrier for controlled delivery of fluvastatin.

PubMed

Amoli-Diva, Mitra; Pourghazi, Kamyar; Mashhadizadeh, Mohammad Hossein

2015-02-01

A novel pH-responsive polymer, poly(methacrylic acid-co-acrylic acid)-co-polyvinyl-pyrrolidone (polymeric nano-carrier) was synthesized and used for encapsulation of 3-aminopropyl triethoxysilane modified Fe3O4 nanoparticles to prepare a new magnetic nano-carrier. The loading and release characteristics of both polymeric and magnetic nano-carriers were investigated using fluvastatin as the model drug. The loading behavior of the carriers was studied by varying concentration of fluvastatin in aqueous medium at 25°C and their release was followed spectrophotometrically (at 304 nm) at 37°C in three different solutions (buffered at pH1.2, 5.5 and 7.2) to simulate gastric and intestine medium. The effect of different parameters on the release of fluvastatin such as the amount of methacrylic acid monomer, cross-linker amount, initiator amount, and magnetic nanoparticles content was also studied. Considering the release kinetics and mechanism of the magnetic nanocarrier besides swelling behavior study of the polymeric nano-carrier reveal Fickian pattern and diffusion controlled mechanism for delivery of fluvastatin. Copyright © 2014 Elsevier B.V. All rights reserved.

Drug solubility in lipid nanocarriers: Influence of lipid matrix and available interfacial area.

PubMed

Göke, Katrin; Bunjes, Heike

2017-08-30

Amongst other strategies for the formulation of poorly water-soluble drugs, solubilization of these drugs in lipid-based formulations is a promising option. Most screening methods for the identification of a suitable lipid-based formulation fail to elucidate the role interfacial effects play for drug solubility in disperse systems. In a novel screening approach called passive drug loading, different preformed lipid nanocarrier dispersions are incubated with drug powder. Afterwards, undissolved drug is filtered off and the amount of solubilized drug is determined. The aim of this study was to identify parameters for drug solubility in pure lipids as well as for drug loading to the lipid-water interface of lipid nanoparticles. Using passive loading, the solubility of eight poorly water-soluble drugs in seven lipid nanocarriers varying in particle size or lipid matrix was investigated. Drug solubility in the nanocarriers did not follow any apparent trend and different drugs dissolved best in different carriers. Drugs with a melting point below approximately 150°C displayed distinctly better solubility than higher melting drugs. Additionally, relating the specific lipid nanocarrier surface area to the drug solubility allowed drawing conclusions on the drug localization. Fenofibrate, dibucaine and, less distinctly also clotrimazole, which all melt below 150°C, were predominantly located in the lipid droplet core of the nanoparticles. In contrast, the five remaining drugs (betamethasone valerate, flufenamic acid, itraconazole, ketoconazole, mefenamic acid) were also located at the lipid-water interface to different, but substantial degrees. The ability to account for drug loading to the lipid-water interface is thus a major advantage of passive loading. Copyright © 2017 Elsevier B.V. All rights reserved.

Dendrimer-based nanocarriers demonstrating a high efficiency for loading and releasing anticancer drugs against cancer cells in vitro and in vivo

NASA Astrophysics Data System (ADS)

Quyen Tran, Ngoc; Khoa Nguyen, Cuu; Phuong Nguyen, Thi

2013-12-01

Dendrimer, a new class of hyper-branched polymer with predetermined molecular weight and well-controlled size, has received much attention in nanobiomedical applications such as drug carrier, gene therapy, disease diagnosis, etc. In this study, pegylated polyamidoamine (PAMAM) dendrimer at generation 3.0 (G 3.0) and carboxylated PAMAM dendrimer G 2.5 were prepared for loading anticancer drugs. For loading cisplatin, carboxylated dendrimer could carry 26.64 wt/wt% of cisplatin. The nanocomplexes have size ranging from 10 to 30 nm in diameter. The drug nanocarrier showed activity against NCI-H460 lung cancer cell line with half maximal inhibitory (IC50) of 23.11 ± 2.08 μg ml-1. Pegylated PAMAM dendrimers (G 3.0) were synthesized below 40 nm in diameter for carrying 5-fluorouracil (5-FU). For 5-FU encapsulation, pegylated dendrimer showed a high drug-loading efficiency of the drug and a slow release profile of 5-FU. The drug nanocarrier system exhibited an antiproliferative activity against MCF-7 cells (breast cancer cell) with a half maximal inhibitory (IC50) of 9.92 ± 0.19 μg ml-1. In vivo tumor xenograft study showed that the 5-FU encapsulated pegylation of dendrimer exhibited a significant decrement in volume of tumor which was generated by MCF-7 cancer cells. These positive results from our studies could pave the ways for further research of drugs dendrimer nanocarriers toward cancer chemotherapy.

Using exosomes, naturally-equipped nanocarriers, for drug delivery.

PubMed

Batrakova, Elena V; Kim, Myung Soo

2015-12-10

Exosomes offer distinct advantages that uniquely position them as highly effective drug carriers. Comprised of cellular membranes with multiple adhesive proteins on their surface, exosomes are known to specialize in cell-cell communications and provide an exclusive approach for the delivery of various therapeutic agents to target cells. In addition, exosomes can be amended through their parental cells to express a targeting moiety on their surface, or supplemented with desired biological activity. Development and validation of exosome-based drug delivery systems are the focus of this review. Different techniques of exosome isolation, characterization, drug loading, and applications in experimental disease models and clinic are discussed. Exosome-based drug formulations may be applied to a wide variety of disorders such as cancer, various infectious, cardiovascular, and neurodegenerative disorders. Overall, exosomes combine benefits of both synthetic nanocarriers and cell-mediated drug delivery systems while avoiding their limitations. Published by Elsevier B.V.

Preparation of chitosan-based multifunctional nanocarriers overcoming multiple barriers for oral delivery of insulin.

PubMed

Li, Lei; Jiang, Guohua; Yu, Weijiang; Liu, Depeng; Chen, Hua; Liu, Yongkun; Tong, Zaizai; Kong, Xiangdong; Yao, Juming

2017-01-01

To overcome multiple barriers for oral delivery of insulin, the chitosan-based multifunctional nanocarriers modified by L-valine (LV, used as a target ligand to facilitate the absorption of the small intestine) and phenylboronic acid (PBA, used as a glucose-responsive unit) have been designed and evaluated in this study. The resultant nanocarriers exhibited low cytotoxicity against HT-29 cells and excellent stability against protein solution. The insulin release behaviors were evaluated triggered by pH and glucose in vitro. The chemical stability of loaded insulin against digestive enzyme were established in presence of simulated gastric fluid (SGF) containing pepsin and simulated intestinal fluid (SIF) containing pancreatin, respectively. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope. After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. This work suggests that L-valine modified chitosan-based multifunctional nanocarriers may be a promising drug delivery carrier for oral administration of insulin. Copyright © 2016 Elsevier B.V. All rights reserved.

Real-time particle tracking for studying intracellular trafficking of pharmaceutical nanocarriers.

PubMed

Huang, Feiran; Watson, Erin; Dempsey, Christopher; Suh, Junghae

2013-01-01

Real-time particle tracking is a technique that combines fluorescence microscopy with object tracking and computing and can be used to extract quantitative transport parameters for small particles inside cells. Since the success of a nanocarrier can often be determined by how effectively it delivers cargo to the target organelle, understanding the complex intracellular transport of pharmaceutical nanocarriers is critical. Real-time particle tracking provides insight into the dynamics of the intracellular behavior of nanoparticles, which may lead to significant improvements in the design and development of novel delivery systems. Unfortunately, this technique is not often fully understood, limiting its implementation by researchers in the field of nanomedicine. In this chapter, one of the most complicated aspects of particle tracking, the mean square displacement (MSD) calculation, is explained in a simple manner designed for the novice particle tracker. Pseudo code for performing the MSD calculation in MATLAB is also provided. This chapter contains clear and comprehensive instructions for a series of basic procedures in the technique of particle tracking. Instructions for performing confocal microscopy of nanoparticle samples are provided, and two methods of determining particle trajectories that do not require commercial particle-tracking software are provided. Trajectory analysis and determination of the tracking resolution are also explained. By providing comprehensive instructions needed to perform particle-tracking experiments, this chapter will enable researchers to gain new insight into the intracellular dynamics of nanocarriers, potentially leading to the development of more effective and intelligent therapeutic delivery vectors.

Features associated with, and the impact of, hemolytic anemia in patients with systemic lupus erythematosus: LX, results from a multiethnic cohort.

PubMed

Durán, Sergio; Apte, Mandar; Alarcón, Graciela S; Marion, Miranda C; Edberg, Jeffrey C; Kimberly, Robert P; Zhang, Jie; Langefeld, Carl D; Vilá, Luis M; Reveille, John D

2008-09-15

To examine the clinical and genetic correlates of hemolytic anemia and its impact on damage accrual and mortality in systemic lupus erythematosus (SLE) patients. SLE patients (American College of Rheumatology [ACR] criteria) of Hispanic (Texan or Puerto Rican), African American, and Caucasian ethnicity from the LUMINA (LUpus in MInorities, NAture versus nurture) cohort were studied. Hemolytic anemia was defined as anemia with reticulocytosis (ACR criterion). The association between degrees of hemolytic anemia and socioeconomic/demographic, clinical, pharmacologic, immunologic, psychological, and behavioral variables was examined by univariable and multivariable (proportional odds model) analyses. Genetic variables (FCGR and Fas/Fas ligand polymorphisms) were examined by 2 degrees of freedom test of association and Cochran-Armitage trend tests. The impact of hemolytic anemia on damage accrual and mortality was examined by multivariable linear and Cox regression analyses, respectively. Of 628 patients studied, 90% were women, 19% were Texan Hispanic, 16% were Puerto Rican Hispanic, 37% were African American, and 28% were Caucasian. Sixty-five (10%) patients developed hemolytic anemia at some time during the disease course, 83% at or before diagnosis. Variables independently associated with degrees of hemolytic anemia were African American ethnicity, thrombocytopenia, and the use of azathioprine. Hemolytic anemia was associated with damage accrual after adjusting for variables known to affect this outcome; however, hemolytic anemia was not associated with mortality. The association of hemolytic anemia with thrombocytopenia suggests a common mechanism in their pathophysiology. Hemolytic anemia is an early disease manifestation and is associated with African American ethnicity and the use of azathioprine; it appears to exert an impact on damage but not on mortality.

Features Associated With, and the Impact of, Hemolytic Anemia in Patients With Systemic Lupus Erythematosus: LX, Results From a Multiethnic Cohort

PubMed Central

DURÁN, SERGIO; APTE, MANDAR; ALARCÓN, GRACIELA S.; MARION, MIRANDA C.; EDBERG, JEFFREY C.; KIMBERLY, ROBERT P.; ZHANG, JIE; LANGEFELD, CARL D.; VILÁ, LUIS M.; REVEILLE, JOHN D.

2009-01-01

Objective To examine the clinical and genetic correlates of hemolytic anemia and its impact on damage accrual and mortality in systemic lupus erythematosus (SLE) patients. Methods SLE patients (American College of Rheumatology [ACR] criteria) of Hispanic (Texan or Puerto Rican), African American, and Caucasian ethnicity from the LUMINA (LUpus in MInorities, NAture versus nurture) cohort were studied. Hemolytic anemia was defined as anemia with reticulocytosis (ACR criterion). The association between degrees of hemolytic anemia and socioeconomic/demographic, clinical, pharmacologic, immunologic, psychological, and behavioral variables was examined by univariable and multivariable (proportional odds model) analyses. Genetic variables (FCGR and Fas/Fas ligand polymorphisms) were examined by 2 degrees of freedom test of association and Cochran-Armitage trend tests. The impact of hemolytic anemia on damage accrual and mortality was examined by multivariable linear and Cox regression analyses, respectively. Results Of 628 patients studied, 90% were women, 19% were Texan Hispanic, 16% were Puerto Rican Hispanic, 37% were African American, and 28% were Caucasian. Sixty-five (10%) patients developed hemolytic anemia at some time during the disease course, 83% at or before diagnosis. Variables independently associated with degrees of hemolytic anemia were African American ethnicity, thrombocytopenia, and the use of azathioprine. Hemolytic anemia was associated with damage accrual after adjusting for variables known to affect this outcome; however, hemolytic anemia was not associated with mortality. Conclusion The association of hemolytic anemia with thrombocytopenia suggests a common mechanism in their pathophysiology. Hemolytic anemia is an early disease manifestation and is associated with African American ethnicity and the use of azathioprine; it appears to exert an impact on damage but not on mortality. PMID:18759263

Susceptibility to β-lactams in β-hemolytic streptococci.

PubMed

Bonofiglio, Laura; Gagetti, Paula; García Gabarrot, Gabriela; Kaufman, Sara; Mollerach, Marta; Toresani, Inés; Vigliarolo, Laura; von Specht, Martha; Lopardo, Horacio A

2018-03-13

Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attributable to different causes. By contrast, some GBS with reduced susceptibility to penicillin have been described, especially in Japan. In this group of bacteria, it is important to highlight that confirmation by reference methods is mandatory when decreased susceptibility to penicillin is suspected as well as checked for the detection of the mechanisms involved. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

[Mechanisms of congenital erythrocyte enzyme deficiencies associated with hemolytic anemia].

PubMed

Boivin, P; Kahn, A

1976-01-01

The search for a mechanism for red cell enzyme deficiency associated with congenital hemolytic anemia, requires one to determine the kinetic and thermodynamic properties of the enzyme reaction and study the physico-chemical and immunological characteristics of the protein which supports enzyme activity. The technique of iso-electric focalisation and the use of specific anti-enzyme antibodies, is the reason for recent progress in the understanding of the mechanism of these deficiencies. Examples of application of these techniques are given in relation to glucose-6-dehydrogenase, pyruvate kinase, glucose phosphate isomerase, phosphofructokinase and phosphoglycerate kinase of deficiencies showing the multiplicity of the molecular mechanisms.

Novel ZnO hollow-nanocarriers containing paclitaxel targeting folate-receptors in a malignant pH-microenvironment for effective monitoring and promoting breast tumor regression

PubMed Central

Puvvada, Nagaprasad; Rajput, Shashi; Kumar, B.N. Prashanth; Sarkar, Siddik; Konar, Suraj; Brunt, Keith R.; Rao, Raj R.; Mazumdar, Abhijit; Das, Swadesh K.; Basu, Ranadhir; Fisher, Paul B.; Mandal, Mahitosh; Pathak, Amita

2015-01-01

Low pH in the tumor micromilieu is a recognized pathological feature of cancer. This attribute of cancerous cells has been targeted herein for the controlled release of chemotherapeutics at the tumour site, while sparing healthy tissues. To this end, pH-sensitive, hollow ZnO-nanocarriers loaded with paclitaxel were synthesized and their efficacy studied in breast cancer in vitro and in vivo. The nanocarriers were surface functionalized with folate using click-chemistry to improve targeted uptake by the malignant cells that over-express folate-receptors. The nanocarriers released ~75% of the paclitaxel payload within six hours in acidic pH, which was accompanied by switching of fluorescence from blue to green and a 10-fold increase in the fluorescence intensity. The fluorescence-switching phenomenon is due to structural collapse of the nanocarriers in the endolysosome. Energy dispersion X-ray mapping and whole animal fluorescent imaging studies were carried out to show that combined pH and folate-receptor targeting reduces off-target accumulation of the nanocarriers. Further, a dual cell-specific and pH-sensitive nanocarrier greatly improved the efficacy of paclitaxel to regress subcutaneous tumors in vivo. These nanocarriers could improve chemotherapy tolerance and increase anti-tumor efficacy, while also providing a novel diagnostic read-out through fluorescent switching that is proportional to drug release in malignant tissues. PMID:26145450

Novel ZnO hollow-nanocarriers containing paclitaxel targeting folate-receptors in a malignant pH-microenvironment for effective monitoring and promoting breast tumor regression

NASA Astrophysics Data System (ADS)

Puvvada, Nagaprasad; Rajput, Shashi; Kumar, B. N. Prashanth; Sarkar, Siddik; Konar, Suraj; Brunt, Keith R.; Rao, Raj R.; Mazumdar, Abhijit; Das, Swadesh K.; Basu, Ranadhir; Fisher, Paul B.; Mandal, Mahitosh; Pathak, Amita

2015-07-01

Low pH in the tumor micromilieu is a recognized pathological feature of cancer. This attribute of cancerous cells has been targeted herein for the controlled release of chemotherapeutics at the tumour site, while sparing healthy tissues. To this end, pH-sensitive, hollow ZnO-nanocarriers loaded with paclitaxel were synthesized and their efficacy studied in breast cancer in vitro and in vivo. The nanocarriers were surface functionalized with folate using click-chemistry to improve targeted uptake by the malignant cells that over-express folate-receptors. The nanocarriers released ~75% of the paclitaxel payload within six hours in acidic pH, which was accompanied by switching of fluorescence from blue to green and a 10-fold increase in the fluorescence intensity. The fluorescence-switching phenomenon is due to structural collapse of the nanocarriers in the endolysosome. Energy dispersion X-ray mapping and whole animal fluorescent imaging studies were carried out to show that combined pH and folate-receptor targeting reduces off-target accumulation of the nanocarriers. Further, a dual cell-specific and pH-sensitive nanocarrier greatly improved the efficacy of paclitaxel to regress subcutaneous tumors in vivo. These nanocarriers could improve chemotherapy tolerance and increase anti-tumor efficacy, while also providing a novel diagnostic read-out through fluorescent switching that is proportional to drug release in malignant tissues.

[Acute renal failure secondary to hemolytic uremic syndrome in a pregnant woman with pre-eclampsia].

PubMed

García-Miguel, F J; Mirón Rodríguez, M F; Alsina Aser, M J

2009-02-01

Acute renal failure is a serious complication of pregnancy associated with a high rate of morbidity and mortality; the incidence is currently 1 per 10,000 pregnancies. The most common causes are gestational hypertension, bleeding, sepsis, and intrinsic renal disease. Other less common pregnancy-related syndromes, such as HELLP syndrome or thrombotic microangiopathy, may also lead to kidney failure. Hemolytic uremic syndrome and thrombotic thrombocytopenic purpura are forms of thrombotic microangiopathy and although neither is specific to pregnancy, the incidence of these entities rises during gestation. The classic symptoms are fever, hemolytic microangiopathic anemia, thrombopenia, neurologic dysfunction, and kidney abnormalities. When renal involvement is the predominant manifestation, the diagnosis is usually hemolytic uremic syndrome.

Validity of rapid antigen detection testing in group A beta-hemolytic streptococcal tonsillopharyngitis.

PubMed

Küçük, Oznur; Biçer, Suat; Giray, Tuba; Cöl, Defne; Erdağ, Gülay Ciler; Gürol, Yeşim; Kaspar, Ciğdem E; Vitrinel, Ayça

2014-02-01

To evaluate the utility of rapid antigen detection testing (RADT) for the diagnosis of group A beta-hemolytic streptococcal tonsillopharyngitis in children, and to detect the sensitivity and specificity of rapid antigen detection of group A beta-hemolytic streptococci from throat specimen compared with throat culture. Rapid antigen detection and throat culture results for group A beta-hemolytic streptococci from outpatients attending university hospital between 1st January 2011 and 31st of December 2011 were evaluated retrospectively. The antigen test negative-throat culture positive patients were investigated for streptococcal carriage. For this purpose, the throat culture results taken from these patients were reviewed after treatment. Eight hundred and ninetytwo children were included in the studywith a mean age of 5.34 y. There were 639 and 253 children in two groups with age of 0-6 and 7-17 y, RADT sensitivity and specificity were found to be 59.5 % and 97.2 %, respectively. The positive predictive value was 87.1 %, whereas negative predictive value was 88.4 %. After treatment of 74 patients with throat culture positive and antigen test negative. Group A beta-hemolytic streptococci were isolated in 12 of them (16.2 %) and accepted as a carrier. The low sensitivity of the RADT may be related to streptococcal carriage in some patients. The throat culture should be repeated after treatment to detect streptococcal carriage.

Effect of flow on endothelial endocytosis of nanocarriers targeted to ICAM-1.

PubMed

Bhowmick, Tridib; Berk, Erik; Cui, Xiumin; Muzykantov, Vladimir R; Muro, Silvia

2012-02-10

Delivery of drugs into the endothelium by nanocarriers targeted to endothelial determinants may improve treatment of vascular maladies. This is the case for intercellular adhesion molecule 1 (ICAM-1), a glycoprotein overexpressed on endothelial cells (ECs) in many pathologies. ICAM-1-targeted nanocarriers bind to and are internalized by ECs via a non-classical pathway, CAM-mediated endocytosis. In this work we studied the effects of endothelial adaptation to physiological flow on the endocytosis of model polymer nanocarriers targeted to ICAM-1 (anti-ICAM/NCs, ~180 nm diameter). Culturing established endothelial-like cells (EAhy926 cells) and primary human umbilical vein ECs (HUVECs) under 4 dyn/cm(2) laminar shear stress for 24 h resulted in flow adaptation: cell elongation and formation of actin stress fibers aligned to the flow direction. Fluorescence microscopy showed that flow-adapted cells internalized anti-ICAM/NCs under flow, although at slower rate versus non flow-adapted cells under static incubation (~35% reduction). Uptake was inhibited by amiloride, whereas marginally affected by filipin and cadaverine, implicating that CAM-endocytosis accounts for anti-ICAM/NC uptake under flow. Internalization under flow was more modestly affected by inhibiting protein kinase C, which regulates actin remodeling during CAM-endocytosis. Actin recruitment to stress fibers that maintain the cell shape under flow may delay uptake of anti-ICAM/NCs under this condition by interfering with actin reorganization needed for CAM-endocytosis. Electron microscopy revealed somewhat slow, yet effective endocytosis of anti-ICAM/NCs by pulmonary endothelium after i.v. injection in mice, similar to that of flow-adapted cell cultures: ~40% (30 min) and 80% (3 h) internalization. Similar to cell culture data, uptake was slightly faster in capillaries with lower shear stress. Further, LPS treatment accelerated internalization of anti-ICAM/NCs in mice. Therefore, regulation of endocytosis

Effect of flow on endothelial endocytosis of nanocarriers targeted to ICAM-1

PubMed Central

Bhowmick, Tridib; Berk, Erik; Cui, Xiumin; Muzykantov, Vladimir R.; Muro, Silvia

2011-01-01

Delivery of drugs into the endothelium by nanocarriers targeted to endothelial determinants may improve treatment of vascular maladies. This is the case for intercellular adhesion molecule 1 (ICAM-1), a glycoprotein overexpressed on endothelial cells (ECs) in many pathologies. ICAM-1-targeted nanocarriers bind to and are internalized by ECs via a non-classical pathway, CAM-mediated endocytosis. In this work we studied the effects of endothelial adaptation to physiological flow on the endocytosis of model polymer nanocarriers targeted to ICAM-1 (anti-ICAM/NCs, ~180-nm diameter). Culturing established endothelial-like cells (EAhy926 cells) and primary human umbilical vein ECs (HUVECs) under 4 dyn/cm2 laminar shear stress for 24 h resulted in flow adaptation: cell elongation and formation of actin stress fibers aligned to the flow direction. Fluorescence microscopy showed that flow-adapted cells internalized anti-ICAM/NCs under flow, although at slower rate versus non flow-adapted cells under static incubation (~35% reduction). Uptake was inhibited by amiloride, whereas marginally affected by filipin and cadaverine, implicating that CAM-endocytosis accounts for anti-ICAM/NC uptake under flow. Internalization under flow was more modestly affected by inhibiting protein kinase C, which regulates actin remodeling during CAM-endocytosis. Actin recruitment to stress fibers that maintain the cell shape under flow may delay uptake of anti-ICAM/NCs under this condition by interfering with actin reorganization needed for CAM-endocytosis. Electron microscopy revealed somewhat slow, yet effective endocytosis of anti-ICAM/NCs by pulmonary endothelium after i.v. injection in mice, similar to that of flow-adapted cell cultures: ~40% (30 min) and 80% (3 h) internalization. Similar to cell culture data, uptake was slightly faster in capillaries with lower shear stress. Further, LPS treatment accelerated internalization of anti-ICAM/NCs in mice. Therefore, regulation of endocytosis of

Development of a macrophage-targeting and phagocytosis-inducing bio-nanocapsule-based nanocarrier for drug delivery.

PubMed

Li, Hao; Tatematsu, Kenji; Somiya, Masaharu; Iijima, Masumi; Kuroda, Shun'ichi

2018-06-01

Macrophage hyperfunction or dysfunction is tightly associated with various diseases, such as osteoporosis, inflammatory disorder, and cancers. However, nearly all conventional drug delivery system (DDS) nanocarriers utilize endocytosis for entering target cells; thus, the development of macrophage-targeting and phagocytosis-inducing DDS nanocarriers for treating these diseases is required. In this study, we developed a hepatitis B virus (HBV) envelope L particle (i.e., bio-nanocapsule (BNC)) outwardly displaying a tandem form of protein G-derived IgG Fc-binding domain and protein L-derived IgG Fab-binding domain (GL-BNC). When conjugated with the macrophage-targeting ligand, mouse IgG2a (mIgG2a), the GL-BNC itself, and the liposome-fused GL-BNC (i.e., GL-virosome) spontaneously initiated aggregation by bridging between the Fc-binding domain and Fab-binding domain with mIgG2a. The aggregates were efficiently taken up by macrophages, whereas this was inhibited by latrunculin B, a phagocytosis-specific inhibitor. The mIgG2a-GL-virosome containing doxorubicin exhibited higher cytotoxicity toward macrophages than conventional liposomes and other BNC-based virosomes. Thus, GL-BNCs and GL-virosomes may constitute promising macrophage-targeting and phagocytosis-inducing DDS nanocarriers. We have developed a novel macrophage-targeting and phagocytosis-inducing bio-nanocapsule (BNC)-based nanocarrier named GL-BNC, which comprises a hepatitis B virus envelope L particle outwardly displaying protein G-derived IgG Fc- and protein L-derived IgG Fab-binding domains in tandem. The GL-BNC alone or liposome-fused form (GL-virosomes) could spontaneously aggregate when conjugated with macrophage-targeting IgGs, inducing phagocytosis by the interaction between IgG Fc of aggregates and FcγR on phagocytes. Thereby these aggregates were efficiently taken up by macrophages. GL-virosomes containing doxorubicin exhibited higher cytotoxicity towards macrophages than ZZ-virosomes and

Nucleoside-Lipid-Based Nanocarriers for Sorafenib Delivery

NASA Astrophysics Data System (ADS)

Benizri, Sebastien; Ferey, Ludivine; Alies, Bruno; Mebarek, Naila; Vacher, Gaelle; Appavoo, Ananda; Staedel, Cathy; Gaudin, Karen; Barthélémy, Philippe

2018-01-01

Although the application of sorafenib, a small inhibitor of tyrosine protein kinases, to cancer treatments remains a worldwide option in chemotherapy, novel strategies are needed to address the low water solubility (< 5 μM), toxicity, and side effects issues of this drug. In this context, the use of nanocarriers is currently investigated in order to overcome these drawbacks. In this contribution, we report a new type of sorafenib-based nanoparticles stabilized by hybrid nucleoside-lipids. The solid lipid nanoparticles (SLNs) showed negative or positive zeta potential values depending on the nucleoside-lipid charge. Transmission electron microscopy of sorafenib-loaded SLNs revealed parallelepiped nanoparticles of about 200 nm. Biological studies achieved on four different cell lines, including liver and breast cancers, revealed enhanced anticancer activities of Sorafenib-based SLNs compared to the free drug. Importantly, contrast phase microscopy images recorded after incubation of cancer cells in the presence of SLNs at high concentration in sorafenib (> 80 μM) revealed a total cancer cell death in all cases. These results highlight the potential of nucleoside-lipid-based SLNs as drug delivery systems.

PEGylation of the GALA Peptide Enhances the Lung-Targeting Activity of Nanocarriers That Contain Encapsulated siRNA.

PubMed

Santiwarangkool, Sarochin; Akita, Hidekata; Nakatani, Taichi; Kusumoto, Kenji; Kimura, Hiroki; Suzuki, Masaru; Nishimura, Masaharu; Sato, Yusuke; Harashima, Hideyoshi

2017-09-01

A α-helical GALA peptide (WEAALAEALAEALAEHLAEALAEALEALAA) has been found to possess dual functions: a pH-dependent inducer of endosomal escape, and a ligand that targets lung endothelium. In the present study, the flexibility of GALA was improved by modifying the edge with polyethylene glycol linker, to increase lung-targeting activity. We first investigated the uptake of the GALA-modified liposomes in which GALA was directly conjugated to the lipid (Cholesterol: GALA/Chol) or the phospholipid-PEG (GALA/PEG 2000 ). The liposomes that were modified with GALA/PEG 2000 (GALA/PEG 2000 -LPs) were taken up at a higher level by human lung endothelial cells (HMVEC-L), in comparison with particles that were modified with GALA/Chol (GALA/Chol-LPs). Small-interfering RNA-encapsulating liposomal-based nanocarriers (multifunctional envelope-type nano device: MEND) that were formulated with a vitamin E-scaffold SS-cleavable pH-activated lipid-like material, namely GALA/PEG 2000 -MEND ssPalmE were also modified with GALA/PEG 2000 . Gene silencing activity in the lung endothelium was then evaluated against an endothelial marker; CD31. In comparison with the unmodified MEND ssPalmE , GALA/PEG 2000 -MEND ssPalmE exhibited a higher silencing activity in the lung. Optimization of GALA/PEG 2000 -MEND ssPalmE resulted in silencing activity in the lung with an ED 50 value of 0.21 mg/kg, while non-specific gene silencing in liver was marginal. Collectively, PEGylated GALA is a promising device for use in targeting the lung endothelium. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Capsid-like supramolecular dendritic systems as pH-responsive nanocarriers for drug penetration and site-specific delivery.

PubMed

Li, Yachao; Lai, Yusi; Xu, Xianghui; Zhang, Xiao; Wu, Yahui; Hu, Cheng; Gu, Zhongwei

2016-02-01

Supramolecular dendritic systems emerge as a promising new-generation bioinspired nanoplatform for nanomedicine. Herein, we report capsid-like mimics self-assembled from peptide dendrimers and functionalized peptides to enhance drug penetration and site-specific delivery for tumor therapy. These drug-loaded supramolecular dendritic systems are endowed with capsid-like component and nanostructure by a facile supramolecular approach. As expected, the drug-loaded capsid-like nanocarriers show some desirable advantages for antitumor drug delivery: a) well-defined nanostructure to improve drug location at tumor site, b) capsid-like architecture to enhance drug penetration, c) high internalization, pH-controlled release and nuclear delivery to jointly achieve site-specific delivery. Based on these merits, the drug-loaded capsid nanocarriers provide efficient tumor suppression to 4T1 tumor bearing BALB/c mice and decrease the DOX-induced toxicity during treatment course. Dendrimers have been tested in many clinical trials as nanocarriers, without great success due to many limitations. Here, the authors attempted to address these issues by developing supramolecular dendritic systems, which mimic capsids in viruses. Both in-vitro and in-vivo studies showed promising results. This work should provide a platform for further development of dendrimer-based nanocarriers for drug delivery. Copyright © 2015 Elsevier Inc. All rights reserved.

NTS-polyplex: A potential nanocarrier for neurotrophic therapy of Parkinson’s disease

PubMed Central

Martinez-Fong, Daniel; Bannon, Michael J.; Trudeau, Louis-Eric; Gonzalez-Barrios, Juan A.; Arango-Rodriguez, Martha L.; Hernandez-Chan, Nancy G.; Reyes-Corona, David; Armendáriz-Borunda, Juan; Navarro-Quiroga, Ivan

2012-01-01

Nanomedicine has focused on targeted neurotrophic gene delivery to the brain as a strategy to stop and reverse neurodegeneration in Parkinson’s disease. Because of improved transfection ability, synthetic nanocarriers have become candidates for neurotrophic therapy. Neurotensin (NTS)-polyplex is a “Trojan horse” synthetic nanocarrier system that enters dopaminergic neurons through NTS receptor internalization to deliver a genetic cargo. The success of preclinical studies with different neurotrophic genes supports the possibility of using NTS-polyplex in nanomedicine. In this review, we describe the mechanism of NTS-polyplex transfection. We discuss the concept that an effective neurotrophic therapy requires a simultaneous effect on the axon terminals and soma of the remaining dopaminergic neurons. We also discuss the future of this strategy for the treatment of Parkinson’s disease. PMID:22406187

Glucose-6-Phosphate Dehydrogenase Deficiency Mimicking Atypical Hemolytic Uremic Syndrome.

PubMed

Walsh, Patrick R; Johnson, Sally; Brocklebank, Vicky; Salvatore, Jacobo; Christian, Martin; Kavanagh, David

2018-02-01

A 4-year-old boy presented with nonimmune hemolysis, thrombocytopenia, and acute kidney injury. Investigations for an underlying cause failed to identify a definitive cause and a putative diagnosis of complement-mediated atypical hemolytic uremic syndrome (aHUS) was made. The patient was started initially on plasma exchange and subsequently eculizumab therapy, after which his kidney function rapidly improved. While on eculizumab therapy, despite adequate complement blockade, he presented 2 more times with hemolytic anemia and thrombocytopenia, but without renal involvement. Genetic analysis did not uncover a mutation in any known aHUS gene (CFH, CFI, CFB, C3, CD46, THBD, INF2, and DGKE) and anti-factor H antibodies were undetectable. Whole-exome sequencing was undertaken to identify a cause for the eculizumab resistance. This revealed a pathogenic variant in G6PD (glucose-6-phosphate dehydrogenase), which was confirmed by functional analysis demonstrating decreased erythrocyte G6PD activity. Eculizumab therapy was withdrawn. Complement-mediated aHUS is a diagnosis of exclusion and this case highlights the diagnostic difficulty that remains without an immediately available biomarker for confirmation. This case of G6PD deficiency presented with a phenotype clinically indistinguishable from complement-mediated aHUS. We recommend that G6PD deficiency be included in the differential diagnosis of patients presenting with aHUS and suggest measuring erythrocyte G6PD concentrations in these patients. Copyright © 2017. Published by Elsevier Inc.

Chitosan-Gated Magnetic-Responsive Nanocarrier for Dual-Modal Optical Imaging, Switchable Drug Release, and Synergistic Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hui; Mu, Qingxin; Revia, Richard

In this study, we present a multifunctional yet structurally simple nanocarrier that has a high drug loading capacity, releases drug in response to onset of an AC magnetic field, and can serve as a long-term imaging contrast agent and effectively kills cancer cells by synergistic action. This nanocarrier (HMMC-NC) has a spherical shell structure with a center cavity of 80 nm in diameter. The shell is comprised of two layers: an inner layer of magnetite that exhibits superparamagnetism and an outer layer of mesoporous carbon embedded with carbon dots that exhibit photoluminescence property. Thus in addition to being a drugmore » carrier, HMMC-NC is also a contrast agent for bioimaging. The switchable drug release is enabled by the chitosan molecules attached on the nanocarrier as the switching material which turns on or off the drug release in response to the application or withdrawal of an AC magnetic field.« less

An Outbreak of Heinz Body Positive Hemolytic Anemia in Chronic Hemodialysis Patients1

PubMed Central

Pyo, Heui-Jung; Kwon, Young Joo; Wee, Kyoung So; Kwon, So Young; Lee, Chang Hong; Kim, Suhnggwon; Lee, Jung Sang; Cho, Soo-Hun; Cha, Chul Whan

1993-01-01

During the four month period, from December 1988 to March 1989, there was an outbreak of Heinz body positive hemolytic anemia in 34 patients undergoing hemodialysis in a 500-bed hospital, Seoul, Korea. The episodes of hemolysis were not reduced by changing the charcoal column and reverse osmosis system, or by adding ascorbic acid to the dialysate. The concentrations of nitrate, copper, aluminum and zinc in the treated water were all within the standards for hemodialysis. The chloramine concentration of the treated water was over 0.6 mg/L, markedly exceeding the allowable level of 0.1 mg/L. This high level of chloramine was proved to be due to the contamination of the water source by raw sewage. After we changed the source of water supply to another, no more episodes of hemolytic anemia occurred. It is concluded that chloramine is one of the major contaminants causing dialysis-induced hemolytic anemia and regular determinations are necessary, especially during winter and dry seasons. PMID:8031729

Nanocarrier possibilities for functional targeting of bioactive peptides and proteins: state-of-the-art.

PubMed

Moutinho, Carla G; Matos, Carla M; Teixeira, José A; Balcão, Victor M

2012-02-01

This review attempts to provide an updated compilation of studies reported in the literature pertaining to production of nanocarriers encasing peptides and/or proteins, in a way that helps the reader direct a bibliographic search and develop an integrated perspective of the subject. Highlights are given to bioactive proteins and peptides, with a special focus on those from dairy sources (including physicochemical characteristics and properties, and biopharmaceutical application possibilities of e.g. lactoferrin and glycomacropeptide), as well as to nanocarrier functional targeting. Features associated with micro- and (multiple) nanoemulsions, micellar systems, liposomes and solid lipid nanoparticles, together with biopharmaceutical considerations, are presented in the text in a systematic fashion.

Ceramic nanocarriers: versatile nanosystem for protein and peptide delivery.

PubMed

Singh, Deependra; Dubey, Pooja; Pradhan, Madhulika; Singh, Manju Rawat

2013-02-01

Proteins and peptides have been established to be the potential drug candidate for various human diseases. But, delivery of these therapeutic protein and peptides is still a challenge due to their several unfavorable properties. Nanotechnology is expanding as a promising tool for the efficient delivery of proteins and peptides. Among numerous nano-based carriers, ceramic nanoparticles have proven themselves as a unique carrier for protein and peptide delivery as they provide a more stable, bioavailable, readily manufacturable, and acceptable proteins and polypeptide formulation. This article provides an overview of the various aspects of ceramic nanoparticles including their classification, methods of preparation, latest advances, and applications as protein and peptide delivery carriers. Ceramic nanocarriers seem to have potential for preserving structural integrity of proteins and peptides, thereby promoting a better therapeutic effect. This approach thus provides pharmaceutical scientists with a new hope for the delivery of proteins and peptides. Still, considerable study on ceramic nanocarrier is necessary with respect to pharmacokinetics, toxicology, and animal studies to confirm their efficiency as well as safety and to establish their clinical usefulness and scale-up to industrial level.

Hemolytic-uremic syndrome in children. A serious hazard of undercooked beef.

PubMed

Robson, W L; Leung, A K

1990-10-01

Hemolytic-uremic syndrome is the leading cause of acute renal failure in childhood. Its incidence in North America is increasing. Escherichia coli O157:H7 is the most common infectious trigger and is spread by contaminated beef products as well as from person to person. Antibiotics or antidiarrheal medications should not be used in the treatment of E coli hemorrhagic colitis or hemolytic-uremic syndrome. Mortality in children with the syndrome has fallen to less than 10% in North America, largely because of careful attention to nutrition, maintenance of a normal fluid and electrolyte balance, and careful monitoring. Education and emotional support of the family are important aspects of the treatment program.

Humanized mouse model of glucose 6-phosphate dehydrogenase deficiency for in vivo assessment of hemolytic toxicity.

PubMed

Rochford, Rosemary; Ohrt, Colin; Baresel, Paul C; Campo, Brice; Sampath, Aruna; Magill, Alan J; Tekwani, Babu L; Walker, Larry A

2013-10-22

Individuals with glucose 6-phosphate dehydrogenase (G6PD) deficiency are at risk for the development of hemolytic anemia when given 8-aminoquinolines (8-AQs), an important class of antimalarial/antiinfective therapeutics. However, there is no suitable animal model that can predict the clinical hemolytic potential of drugs. We developed and validated a human (hu)RBC-SCID mouse model by giving nonobese diabetic/SCID mice daily transfusions of huRBCs from G6PD-deficient donors. Treatment of SCID mice engrafted with G6PD-deficient huRBCs with primaquine, an 8-AQ, resulted in a dose-dependent selective loss of huRBCs. To validate the specificity of this model, we tested known nonhemolytic antimalarial drugs: mefloquine, chloroquine, doxycycline, and pyrimethamine. No significant loss of G6PD-deficient huRBCs was observed. Treatment with drugs known to cause hemolytic toxicity (pamaquine, sitamaquine, tafenoquine, and dapsone) resulted in loss of G6PD-deficient huRBCs comparable to primaquine. This mouse model provides an important tool to test drugs for their potential to cause hemolytic toxicity in G6PD-deficient populations.

Polymer Nanocarriers to Enhance the Efficiency of Platinum-Based Chemotherapeutics

NASA Astrophysics Data System (ADS)

Callari, Manuela

The aim of this Thesis was to design and prepare polymer nanocarriers capable of encapsulating, carrying and delivering platinum-based chemotherapeutics. Polymer nanocarrier have been widely studied and employed as platinum drug delivery systems with the primary scope to overcome limitations presented by platinum-based chemotherapeutics. The conjugation of platinum onto polymers, however, presents some challenges, and, although there has been great progress in the field of drug delivery in the past years, to date only three polymer nanocarriers for platinum drugs have found their way to the clinic. In this Thesis, hydrophilic block copolymers were synthesised via reversible addition fragmentation chain transfer (RAFT) polymerisation or N-carboxyanhydride ring-opening polymerization (NCA-ROP). Upon attachment of a hydrophobic platinum drug the block copolymer becomes amphiphilic and can self-assemble in aqueous media into nanoparticles of different morphology depending on the block copolymer features. Spherical micelles consisting of a poly(methacrylic acid) core which conjugates and encapsulates the platinum chemotherapeutic and a hydrophilic shell made of sugar blocks were prepared and their biological activities compared in vitro. Among the sugars considered here, fructose based micelles showed promising results in terms of their targeting ability towards breast cancer cells. Consequently, fructose-shelled micelles were selected to explore the effect of different loading quantities of platinum drug. It was discovered that the amount of platinum in the core of the micelle highly influences the internal morphology of the micelle which, in turn, affects the micelle-cell interactions. Micelles with low dual drug loading had better cellular uptake and higher toxicity than the micelles with high drug loading, despite having the same fructose-based outer shell. Interestingly, this aspect had been neglected by literature so far, and is important to explore. Micelles made

Probing the intracellular fate of supramolecular nanocarriers and their cargo with FRET schemes

NASA Astrophysics Data System (ADS)

Thapaliya, Ek Raj; Fowley, Colin; Callan, Bridgeen; Tang, Sicheng; Zhang, Yang; Callan, John F.; Raymo, Françisco M.

2017-02-01

We designed a strategy to monitor self-assembling supramolecular nanocarriers and their cargo simultaneously in the intracellular space with fluorescence measurements. It is based on Förster resonance energy transfer (FRET) between complementary chromophores covalently integrated in the macromolecular backbone of amphiphilic polymers and/or noncovalently encapsulated in supramolecular assemblies of the amphiphilic components. Indeed, these polymers assemble into a micelles in aqueous phase to bring energy donors and acceptors in close proximity and allow energy transfer. The resulting supramolecular assemblies maintain their integrity after travelling into the intracellular space and do not lose their molecular guests in the process. Furthermore, this mechanism can also be exploited to probe the fate of complementary nanoparticles introduced within cells in consecutive incubation steps. Efficient energy transfer occurs in the intracellular space after the sequential incubation of nanocarriers incorporating donors first and then nanoparticles containing acceptors or vice versa. The two sets of nanostructured assemblies ultimately co-localize in the cell interior to bring donors and acceptors together and enable energy transfer. Thus, this protocol is particularly valuable to monitor the transport properties of supramolecular nanocarriers inside living cells and can eventually contribute to the fundamental understating of the ability of these promising vehicles to deliver contrast agents and/or drugs intracellularly in view of possible diagnostics and/or therapeutic applications.

Facile fabrication of a near-infrared responsive nanocarrier for spatiotemporally controlled chemo-photothermal synergistic cancer therapy

NASA Astrophysics Data System (ADS)

Wan, Hao; Zhang, Yi; Liu, Zheyi; Xu, Guiju; Huang, Guang; Ji, Yongsheng; Xiong, Zhichao; Zhang, Quanqing; Dong, Jing; Zhang, Weibing; Zou, Hanfa

2014-07-01

Remote-controlled nanocarriers for drug delivery are of great promise to provide timely, sensitive and spatiotemporally selective treatments for cancer therapy. Due to convenient and precise manipulation, deep penetration through tissues and excellent biocompatibility, near-infrared (NIR) irradiation is a preferred external stimulus for triggering the release of loaded drugs. In this work, for spatiotemporally controlled chemo-photothermal synergistic cancer therapy, a NIR responsive nanocarrier was fabricated using reduced graphene oxide nanosheets (rNGO) decorated with mesoporous silica shell and the subsequent functionalization of the thermoresponsive polymer brushes (pNIPAM-co-pAAm) at the outlet of the silica pore channels. rNGO, which combined with the mesoporous silica shell provide a high loading capacity for anticancer drugs (doxorubicin, DOX), was assigned to sense NIR irradiation for the manipulation of pNIPAM-co-pAAm valve to control the diffusion of loaded DOX. Under NIR irradiation, rNGO would generate heat, which could not only elevate the surrounding temperature over the low critical solution temperature (LCST) of pNIPAM-co-pAAm to open the thermoresponsive polymer valve and promote the diffusion of DOX, but also kill the cancer cells through the hypothermia effect. By manipulating NIR irradiation, the nanocarrier exhibited efficiently controlled release of loaded DOX both in the buffer and in living HeLa cells (the model cancer cells), providing powerful and site-targeted treatments, which can be attributed to synergistic effects of chemo-photothermal therapy. To sum up, this novel nanocarrier is an excellent drug delivery platform in remote-controlled chemo-photothermal synergistic cancer therapy via NIR irradiation.Remote-controlled nanocarriers for drug delivery are of great promise to provide timely, sensitive and spatiotemporally selective treatments for cancer therapy. Due to convenient and precise manipulation, deep penetration through

Protease-mediated Inflammation: An In Vitro Human Keratinocyte-based Screening Tool for Anti-inflammatory Drug Nanocarrier Systems

NASA Astrophysics Data System (ADS)

Frombach, Janna; Lohan, Silke B.; Lemm, Davina; Gruner, Paul; Hasler, Julia; Ahlberg, Sebastian; Blume-Peytavi, Ulrike; Unbehauen, Michael; Haag, Rainer; Meinke, Martina C.; Vogt, Annika

2018-05-01

Refined encapsulation approaches in dermatotherapy gain increased interest. There is need of reproducible in vitro systems representing disease features to screen drug delivery systems for preclinical assessment. Inflammatory human skin diseases are commonly accompanied by abnormal epidermal differentiation and barrier impairment. Serine proteases (SPs) and their inhibitors play a critical role in such dysfunctional differentiation. SPs also initiate cellular pathways via activation of protease-activated receptors, which contribute to inflammation. Thus, function and activity of SPs should be considered for the design of new therapies of such disorders. Herein, we established a novel simplified cell culture model, based on SP-mediated inflammation suitable to assess nanocarriers loaded with anti-inflammatory drugs. SP-mediated inflammation and the regulatory effect of free or encapsulated dexamethasone were determined by measuring interleukin-6 and interleukin-8 in culture medium of HaCaT (human adult low calcium temperature)-keratinocytes. Additionally, radical formation was analyzed by electron paramagnetic resonance spectroscopy. Cellular uptake of core-multishell nanocarriers was investigated by fluorescence microscopy. Cytotoxicity of all additives was determined by a viability assay. SP-Stimulation of keratinocytes resulted in increased radical production and release of inflammatory cytokines without affecting cell viability. Induced inflammation was successfully downregulated by addition of free or encapsulated dexamethasone. SP-addition can be used as inflammatory stimulus in cell culture to mimic effects of aberrant enzymatic activities found in skin of atopic dermatitis patients. The set-up is appropriate as a preliminary test to examine the effectiveness of new molecules or delivery-systems to counteract serine protease-mediated inflammatory processes prior to skin studies.

The effect of size and polymer architecture of doxorubicin-poly(ethylene) glycol conjugate nanocarriers on breast duct retention, potency and toxicity.

PubMed

Gu, Zichao; Gao, Dayuan; Al-Zubaydi, Firas; Li, Shike; Singh, Yashveer; Rivera, Kristia; Holloway, Jennifer; Szekely, Zoltan; Love, Susan; Sinko, Patrick J

2018-04-23

Although systemic administration of chemotherapeutic agents is routinely used for treating invasive breast cancer, the only therapeutic options for ductal carcinoma in situ (DCIS) are surgery and radiation. Treating DCIS by delivering drugs locally to the affected milk duct offers significant advantages over systemic administration, including reduced systemic and breast toxicities, as well as a greatly reduced need for surgery and radiation. In this study, mammary gland retention and toxicity of intraductally administered poly(ethylene) glycol-doxorubicin (PEG-DOX) polymeric conjugate nanocarriers of varying molecular sizes and architectures were investigated. Nanocarriers were formed by conjugating one or more copies of doxorubicin to PEG polymers, of varying molecular weights (5, 10, 20, and 40 kDa) and architectures (linear, four-arm and eight-arm). Cytotoxicity against MCF7 cells, a human breast cancer cell line, was assessed, and IC 50 values were calculated. The nanocarriers were intraductally administered into the mammary glands of female retired breeder Sprague-Dawley rats. Whole body images were captured using in vivo optical imaging, and changes in ductal structure as well local inflammation were monitored. Fluorescence intensities were monitored, over time, to evaluate nanocarrier mammary gland retention half-lives (t 1/2 ). The IC 50 values of PEG-DOX nanocarriers against MCF7 cells were 40 kDa PEG-(DOX) 4 (1.23 μM) < 5 kDa PEG-DOX (1.76 μM) < 40 kDa PEG-(DOX) 8 (3.49 μM) < 10 kDa PEG-DOX (3.86 μM) < 20 kDa PEG-DOX (8.96 μM) < 40 kDa PEG-DOX (18.11 μM), whereas the IC 50 of free DOX was only 0.14 μM. The t 1/2 of linear 5, 20, and 40 kDa nanocarriers were 2.2 ± 0.3, 3.6 ± 0.6, and 13.1 ± 3.4 h, whereas the retention t 1/2 of 4- and 8-arm 40 kDa nanocarriers were 14.9 ± 5.6 h and 11.9 ± 2.9 h, respectively. The retention t 1/2 of free doxorubicin was 2.0 ± 0.4�

Comparison of Directigen Group A Strep Test with a traditional culture technique for detection of group A beta-hemolytic streptococci.

PubMed Central

McCusker, J J; McCoy, E L; Young, C L; Alamares, R; Hirsch, L S

1984-01-01

The Directigen Group A Strep Test (DGAST), a new rapid method of detecting group A beta-hemolytic streptococci directly from throat swabs, was compared with a traditional culture technique for the detection of group A beta-hemolytic streptococci. Five hundred oropharyngeal swabs from pediatric and adult patients were cultured and then processed by using the DGAST. Of the 144 specimens positive by culture, 131 were DGAST positive (sensitivity, 90.9%). Of the 356 specimens negative by culture, 353 were DGAST negative (specificity, 99.2%). Twelve of the 13 false-negative DGAST results were from pediatric patients. One hundred isolates of non-group A beta-hemolytic streptococci were recovered, primarily groups C, F, and G. The DGAST is easy to perform, rapid, sensitive, and very specific for detection of group A beta-hemolytic streptococci directly from swabs. Supplementing the DGAST with a culture on a 5% sheep blood agar plate would enhance detection of group A beta-hemolytic streptococci, especially in pediatric patients. PMID:6386884

Venom from Opisthacanthus elatus scorpion of Colombia, could be more hemolytic and less neurotoxic than thought.

PubMed

Estrada-Gómez, Sebastián; Vargas Muñoz, Leidy Johana; Saldarriaga-Córdoba, Mónica; Quintana Castillo, Juan Carlos

2016-01-01

We report the first biochemical, biological, pharmacological and partial proteomic characterization studies of the Opisthancanthus elatus venom (Gervais, 1844) from Colombia. The Reverse Phase High-Performance Liquid Chromatography venom profile showed 28 main well-defined peaks, most eluting between 20 and 45min (18-30% of acetonitrile, respectively). High-resolution mass analysis indicates the presence of 106 components ranging from 806.59742Da to 16849.4139Da. O. elatus venom showed hemolytic activity and hydrolyzed the specific substrate BapNa suggesting the presence of proteins with serine-protease activity. Collected RP-HPLC fractions eluting at 52.6, 55.5, 55.8, 56.2, and 63.9min (PLA2 region between 33 and 40% of acetonitrile), showed hemolytic activity and hydrolyzed the synthetic substrate 4-nitro-3-octanoyloxy-benzoic acid, indicating the presence of compounds with phospholipases A2 activity. These RP-HPLC fractions, showed molecular masses values up to 13978.19546Da, corroborating the possible presence of the mentioned enzymes. Tryptic digestion and MS/MS analysis showed the presence of a phospholipase like fragment, similar to on described in other Opisthacanthus genus studies. No coagulant activity was observed. No larvicidal or antimicrobial activity was observed at concentrations evaluated. Lethal and toxic activity is expected at doses above 100mg/kg, no neurotoxic effects were detected at lower doses. In conclusion, O. elatus exhibits a venom with a predominant phospholipase A2 activity than thought; mammal's neurotoxic activity is expected above the 100mg/kg, which is very high compared to the venom from other neurotoxic scorpions. Copyright © 2015 Elsevier B.V. All rights reserved.

Immune hemolytic anemia associated with probenecid.

PubMed

Sosler, S D; Behzad, O; Garratty, G; Lee, C L; Postoway, N; Khomo, O

1985-09-01

Upon hospital admission a patient was found to have severe anemia and a strongly positive direct antiglobulin test (DAT). The patient was taking probenecid periodically for gout. An antibody was detected in the patient's serum that only reacted with red blood cells (RBCs) when probenecid was added. Eluates from the patient's RBCs, with and without the presence of drug, were nonreactive. Upon the discontinuation of probenecid, the patient's hemoglobin level improved steadily. We believe this to be the first reported case of immune hemolytic anemia associated with probenecid.

In vivo real-time fluorescence visualization and brain-targeting mechanisms of lipid nanocarriers with different fatty ester:oil ratios.

PubMed

Wen, Chih-Jen; Yen, Tzu-Chen; Al-Suwayeh, Saleh A; Chang, Hui-Wen; Fang, Jia-You

2011-11-01

The objective of the present work was to investigate the influence of the inner cores of lipid nanocarriers on the efficiency of brain targeting. Cetyl palmitate and squalene were respectively chosen as the solid lipid and liquid oil in the inner phase of the nanocarriers. Nanoparticulate systems with different cetyl palmitate/squalene ratios were compared by evaluating the size, zeta potential, molecular environment, and mobility of lipids in the systems. The particulate diameter ranged from 190 to 210 nm, with systems containing 100% cetyl palmitate in the matrix (solid lipid nanoparticles [SLN]) showing the smallest size, followed by systems with both cetyl palmitate and squalene (nanostructured lipid carriers [NLC]) and with 100% squalene (lipid emulsions [LE]). A cationic surfactant, Forestall, was used to produce a positive surface charge of 40-55 mW. The in vitro release was evaluated using various dyes located in different phases of the nanocarriers. The release of sulforhodamine B occurred in a sustained manner from the shell of the nanocarriers. The in vivo brain distribution of lipid nanosystems after an intravenous injection into rats was monitored by a real-time fluorescence imaging system. LE showed higher brain accumulation than SLN and NLC. NLC only exhibited a slightly higher brain accumulation compared with the aqueous control. Incorporation of sulforhodamine B into LE could prolong its retention in the brain from 20 to 50 min. The results were further confirmed by imaging the entire brain and brain slices. The specific association of lipid nanocarriers with rat brain endothelial cells (bEnd3) was demonstrated using fluorescence microscopy. The cellular uptake of LE and SLN was higher compared with NLC and the aqueous control. LE were observed to be internalized by cells through caveola-mediated and macropinocytotic energy-dependent endocytosis. The experimental profiles indicated that LE with moderate additives are a promising brain

Gradient-dependent release of the model drug TRITC-dextran from FITC-labeled BSA hydrogel nanocarriers in the hair follicles of porcine ear skin.

PubMed

Tran, Ngo Bich Nga Nathalie; Knorr, Fanny; Mak, Wing Cheung; Cheung, Kwan Yee; Richter, Heike; Meinke, Martina; Lademann, Jürgen; Patzelt, Alexa

2017-07-01

Hair follicle research is currently focused on the development of drug-loaded nanocarriers for the targeting of follicular structures in the treatment of skin and hair follicle-related disorders. In the present study, a dual-label nanocarrier system was implemented in which FITC-labeled BSA hydrogel nanocarriers loaded with the model drug and dye TRITC-dextran were applied topically to porcine ear skin. Follicular penetration and the distribution of both dyes corresponding to the nanocarriers and the model drug in the follicular ducts subsequent to administration to the skin were investigated using confocal laser scanning microscopy. The release of TRITC-dextran from the particles was induced by washing of the nanocarriers, which were kept in a buffer containing TRITC-labeled dextran to balance out the diffusion of the dextran during storage, thereby changing the concentration gradient. The results showed a slightly but statistically significantly deeper follicular penetration of fluorescent signals corresponding to TRITC-dextran as opposed to fluorescence corresponding to the FITC-labeled particles. The different localizations of the dyes in the cross-sections of the skin samples evidenced the release of the model drug from the labeled nanoparticles. Copyright © 2016 Elsevier B.V. All rights reserved.

Delivery of therapeutics using nanocarriers for targeting cancer cells and cancer stem cells.

PubMed

Krishnamurthy, Sangeetha; Ke, Xiyu; Yang, Yi Yan

2015-01-01

Development of cancer resistance, cancer relapse and metastasis are attributed to the presence of cancer stem cells (CSCs). Eradication of this subpopulation has been shown to increase life expectancy of patients. Since the discovery of CSCs a decade ago, several strategies have been devised to specifically target them but with limited success. Nanocarriers have recently been employed to deliver anti-CSC therapeutics for reducing the population of CSCs at the tumor site with great success. This review discusses the different therapeutic strategies that have been employed using nanocarriers, their advantages, success in targeting CSCs and the challenges that are to be overcome. Exploiting this new modality of cancer treatment in the coming decade may improve outcomes profoundly with promise of effective treatment response and reducing relapse and metastasis.

Designing Dendrimer and Miktoarm Polymer Based Multi-Tasking Nanocarriers for Efficient Medical Therapy.

PubMed

Sharma, Anjali; Kakkar, Ashok

2015-09-17

To address current complex health problems, there has been an increasing demand for smart nanocarriers that could perform multiple complimentary biological tasks with high efficacy. This has provoked the design of tailor made nanocarriers, and the scientific community has made tremendous effort in meeting daunting challenges associated with synthetically articulating multiple functions into a single scaffold. Branched and hyper-branched macromolecular architectures have offered opportunities in enabling carriers with capabilities including location, delivery, imaging etc. Development of simple and versatile synthetic methodologies for these nanomaterials has been the key in diversifying macromolecule based medical therapy and treatment. This review highlights the advancement from conventional "only one function" to multifunctional nanomedicine. It is achieved by synthetic elaboration of multivalent platforms in miktoarm polymers and dendrimers by physical encapsulation, covalent linking and combinations thereof.

Multifunctional Nanocarriers for diagnostics, drug delivery and targeted treatment across blood-brain barrier: perspectives on tracking and neuroimaging.

PubMed

Bhaskar, Sonu; Tian, Furong; Stoeger, Tobias; Kreyling, Wolfgang; de la Fuente, Jesús M; Grazú, Valeria; Borm, Paul; Estrada, Giovani; Ntziachristos, Vasilis; Razansky, Daniel

2010-03-03

Nanotechnology has brought a variety of new possibilities into biological discovery and clinical practice. In particular, nano-scaled carriers have revolutionalized drug delivery, allowing for therapeutic agents to be selectively targeted on an organ, tissue and cell specific level, also minimizing exposure of healthy tissue to drugs. In this review we discuss and analyze three issues, which are considered to be at the core of nano-scaled drug delivery systems, namely functionalization of nanocarriers, delivery to target organs and in vivo imaging. The latest developments on highly specific conjugation strategies that are used to attach biomolecules to the surface of nanoparticles (NP) are first reviewed. Besides drug carrying capabilities, the functionalization of nanocarriers also facilitate their transport to primary target organs. We highlight the leading advantage of nanocarriers, i.e. their ability to cross the blood-brain barrier (BBB), a tightly packed layer of endothelial cells surrounding the brain that prevents high-molecular weight molecules from entering the brain. The BBB has several transport molecules such as growth factors, insulin and transferrin that can potentially increase the efficiency and kinetics of brain-targeting nanocarriers. Potential treatments for common neurological disorders, such as stroke, tumours and Alzheimer's, are therefore a much sought-after application of nanomedicine. Likewise any other drug delivery system, a number of parameters need to be registered once functionalized NPs are administered, for instance their efficiency in organ-selective targeting, bioaccumulation and excretion. Finally, direct in vivo imaging of nanomaterials is an exciting recent field that can provide real-time tracking of those nanocarriers. We review a range of systems suitable for in vivo imaging and monitoring of drug delivery, with an emphasis on most recently introduced molecular imaging modalities based on optical and hybrid contrast, such as

Clinical advances of nanocarrier-based cancer therapy and diagnostics.

PubMed

Luque-Michel, Edurne; Imbuluzqueta, Edurne; Sebastián, Víctor; Blanco-Prieto, María J

2017-01-01

Cancer is a leading cause of death worldwide and efficient new strategies are urgently needed to combat its high mortality and morbidity statistics. Fortunately, over the years, nanotechnology has evolved as a frontrunner in the areas of imaging, diagnostics and therapy, giving the possibility of monitoring, evaluating and individualizing cancer treatments in real-time. Areas covered: Polymer-based nanocarriers have been extensively studied to maximize cancer treatment efficacy and minimize the adverse effects of standard therapeutics. Regarding diagnosis, nanomaterials like quantum dots, iron oxide nanoparticles or gold nanoparticles have been developed to provide rapid, sensitive detection of cancer and, therefore, facilitate early treatment and monitoring of the disease. Therefore, multifunctional nanosystems with both imaging and therapy functionalities bring us a step closer to delivering precision/personalized medicine in the cancer setting. Expert opinion: There are multiple barriers for these new nanosystems to enter the clinic, but it is expected that in the near future, nanocarriers, together with new 'targeted drugs', could replace our current treatments and cancer could become a nonfatal disease with good recovery rates. Joint efforts between scientists, clinicians, the pharmaceutical industry and legislative bodies are needed to bring to fruition the application of nanosystems in the clinical management of cancer.

Mesoporous silica nanocarriers encapsulated antimalarials with high therapeutic performance.

PubMed

Amolegbe, Saliu Alao; Hirano, Yui; Adebayo, Joseph Oluwatope; Ademowo, Olusegun George; Balogun, Elizabeth Abidemi; Obaleye, Joshua Ayoola; Krettli, Antoniana Ursine; Yu, Chengzhong; Hayami, Shinya

2018-02-15

The use of nanocarriers in drug delivery is a breakeven research and has received a clarion call in biomedicine globally. Herein, two newly nano-biomaterials: MCM-41 encapsulated quinine (MCM-41 ⊃ QN) (1) and 3-phenylpropyl silane functionalized MCM-41 loaded QN (pMCM-41 ⊃ QN) (2) were synthesized and well characterized. 1 and 2 along with our two already reported nano-antimalarial drugs (MCM-41 ⊃ ATS) (3) and 3-aminopropyl silane functionalized MCM-41 contained ATS (aMCM-41 ⊃ ATS) (4) were screened in vitro for their activity against P. falciparium W2 strain, cytotoxicity against BGM cells and in vivo for their activity against Plasmodium bergheiNK65. 1 has the highest antimalarial activity in vivo against P. berghei NK65, (ED 50 : < 0.0625 mg/kg body weight) and higher mean survival time compared to the other nano biomaterials or unencapsulated drugs at doses higher than 0.0625 mg/kg body weight. This encapsulation strategy of MCM-41 ⊃ QN (1) stands very useful and effective in delivering the drug to the target cells compared to other delivery systems and therefore, this encapsulated drug may be considered for rational drug design.

Neonatal management and outcome in alloimmune hemolytic disease.

PubMed

Ree, Isabelle M C; Smits-Wintjens, Vivianne E H J; van der Bom, Johanna G; van Klink, Jeanine M M; Oepkes, Dick; Lopriore, Enrico

2017-07-01

Hemolytic disease of the fetus and newborn (HDFN) occurs when fetal and neonatal erythroid cells are destroyed by maternal erythrocyte alloantibodies, it leads to anemia and hydrops in the fetus, and hyperbilirubinemia and kernicterus in the newborn. Postnatal care consists of intensive phototherapy and exchange transfusions to treat severe hyperbilirubinemia and top-up transfusions to treat early and late anemia. Other postnatal complications have been reported such as thrombocytopenia, iron overload and cholestasis requiring specific management. Areas covered: This review focusses on the current neonatal management and outcome of hemolytic disease and discusses postnatal treatment options as well as literature on long-term neurodevelopmental outcome. Expert commentary: Despite major advances in neonatal management, multiple issues have to be addressed to optimize postnatal management and completely eradicate kernicterus. Except for strict adherence to guidelines, improvement could be achieved by clarifying the epidemiology and pathophysiology of HDFN. Several pharmacotherapeutic agents should be further researched as alternative treatment options in hyperbilirubinemia, including immunoglobulins, albumin, phenobarbital, metalloporphyrins, zinc, clofibrate and prebiotics. Larger trials are warranted to evaluate EPO, folate and vitamin E in neonates. Long-term follow-up studies are needed in HDFN, especially on thrombocytopenia, iron overload and cholestasis.

The Use of Nanocarriers in Acute Myeloid Leukaemia Therapy: Challenges and Current Status.

PubMed

Sauvage, Félix; Barratt, Gillian; Herfindal, Lars; Vergnaud-Gauduchon, Juliette

2016-01-01

Chemotherapy for AML is hampered by severe side-effects and failure to eliminate all the blasts that eventually leads to relapse. The use of nanosized particulate drug carriers such as liposomes and polymeric nanoparticles has the potential to improve AML therapy by delivering more of the drug to the disease site, thereby reducing toxicity. For example, encapsulation in liposomes reduces the cardiotoxicity of anthracyclines, giving an improved therapeutic index. Moreover, when the surface properties are engineered appropriately, nanocarriers remain in the circulation and extravasate in tissues with sinusoidal capillaries, one of which is bone marrow, leading to a more favourable distribution of the associated drug. Drug carrier technology contributes to the development of newer drugs, such as nucleic acids that can be protected from degradation and delivered into cells, thus opening the way for gene-silencing strategies. Furthermore, carrier systems provide a means of dispersing poorly water-soluble molecule for in vivo administration and thus increase the "druggability" of new lead compounds, such as heat-shock protein inhibitors. Particulate carriers can transport more than one active agent, allowing synergistic action and theranostic strategies. Notably, phase I and II clinical trials are being performed with CPX-351, a liposomal formulation containing cytarabine and daunorubicin at an optimal ratio. Finally, by attaching suitable ligands to the nanocarrier surface, specific targeting to AML cells can be achieved. In this review, we give examples of successful targeting to folate and transferrin receptors against AML.

Humanized mouse model of glucose 6-phosphate dehydrogenase deficiency for in vivo assessment of hemolytic toxicity

PubMed Central

Rochford, Rosemary; Ohrt, Colin; Baresel, Paul C.; Campo, Brice; Sampath, Aruna; Magill, Alan J.; Tekwani, Babu L.; Walker, Larry A.

2013-01-01

Individuals with glucose 6-phosphate dehydrogenase (G6PD) deficiency are at risk for the development of hemolytic anemia when given 8-aminoquinolines (8-AQs), an important class of antimalarial/antiinfective therapeutics. However, there is no suitable animal model that can predict the clinical hemolytic potential of drugs. We developed and validated a human (hu)RBC-SCID mouse model by giving nonobese diabetic/SCID mice daily transfusions of huRBCs from G6PD-deficient donors. Treatment of SCID mice engrafted with G6PD-deficient huRBCs with primaquine, an 8-AQ, resulted in a dose-dependent selective loss of huRBCs. To validate the specificity of this model, we tested known nonhemolytic antimalarial drugs: mefloquine, chloroquine, doxycycline, and pyrimethamine. No significant loss of G6PD-deficient huRBCs was observed. Treatment with drugs known to cause hemolytic toxicity (pamaquine, sitamaquine, tafenoquine, and dapsone) resulted in loss of G6PD-deficient huRBCs comparable to primaquine. This mouse model provides an important tool to test drugs for their potential to cause hemolytic toxicity in G6PD-deficient populations. PMID:24101478

Idiopathic autoimmune hemolytic anemia due to lecithin overdose: a case report

PubMed Central

2009-01-01

Introduction Idiopathic Autoimmune Hemolytic Anemia is a potentially fatal condition which requires prompt and potent treatment. Diagnosis of idiopathic autoimmune hemolytic anemia requires both serologic evidence of autoantibody presence and hemolysis. Although most of the times it is considered idiopathic, several underlying causes have been identified, like autoimmune and connective tissue diseases, viral infections, drugs or hyper function of the immune system. To our knowledge, this is the first case in the international literature describing lecithin-induced autoimmune hemolytic anemia. Case Presentation This case report is to highlight a rare but dangerous adverse reaction to overdose of lecithin. A 38 year old white female from Greece, presented to our emergency room with progressive fatigue over a period of ten days and icteric discoloration of her skin and conjunctiva. The patient had been taking lecithin supplements (1200 mg, 3 capsules a day) over a period of ten days for weight loss. She reports that the last 3 days, prior to the examination, she took 5 capsules/day, so that the supplement would take effect more rapidly. Her past medical, social and family history showed no disturbance. Relatives of the patient were requested to submit any blood-tests taken over a period of 20 days prior to the onset of symptoms caused by Lecithin. All tests proved that all functions were within normal scale. Her physical examination revealed pallor and jaundice without palpable hepatosplenomegaly. Blood biochemistry tests showed total bilirubin 7.5 mg/dl, with indirect bilirubin 6.4 mg/dl and complete blood count showed hemoglobin 7.6 g/dl with blood levels 21.4%. Conclusion In every case of idiopathic autoimmune hemolytic anemia the administration of pharmaceutical substances should always be examined, except for the standard reasons that cause it. In this case the cause of hemolysis was attributed to the excessive intake of lecithin capsules for the loss of body

Prevalence of β-hemolytic Streptococcus in children with special health care needs.

PubMed

Morais, Viviane Martha Santos de; Orsi, Alice Ramos; Maranhão, Fernanda Cristina de Albuquerque; Castro, Therezita Maria Peixoto Patury Galvão; Castro, Karina Cavalcante Beltrão de; Silva, Denise Maria Wanderlei

2012-10-01

Pharyngotonsillitis by β-hemolytic Streptococcus mostly affects children and immunocompromised, being Streptococcus pyogenes (Group A) the most common agent in bacterial pharyngotonsillitis. This work targeted the research of β-hemolytic Streptococcus Group-A (SBHGA) and No-A (SBHGNA) in the oropharynx of individuals with special health needs from the APAE (Maceió-AL). A prospective study with oropharynx samples from patients with Down syndrome and other mental disorders (test) and students from a private school (control) aged 5-15 years. Cultures in blood agar (5%) were identified through Gram/catalase tests and bacitracin/trimethoprim-sulfamethoxazole disk diffusion method, applying the chi-squared statistical analysis. A total of 222 bacterial colonies were isolated in 74 individuals from APAE and 65 in the control group. In the test group, previous episodes of pharyngotonsillitis were reported by 36.49% (27/74) and 9.46% (7/74) were diagnosed with symptoms and/or signs suggestive of oropharynx infection. No positive sample of S. pyogenes was confirmed at APAE, being all samples classified as SBHGNA, with 5 SBHGA in the control group. The early identification of β-hemolytic Streptococcus is important for the fast treatment of pharyngotonsillitis and the absence of S. pyogenes avoid future suppurative or not-suppurative sequels in the group from APAE.

Cytosolic co-delivery of miRNA-34a and docetaxel with core-shell nanocarriers via caveolae-mediated pathway for the treatment of metastatic breast cancer

NASA Astrophysics Data System (ADS)

Zhang, Li; Yang, Xin; Lv, Yaqi; Xin, Xiaofei; Qin, Chao; Han, Xiaopeng; Yang, Lei; He, Wei; Yin, Lifang

2017-04-01

Co-delivery of microRNAs and chemotherapeutic drugs into tumor cells is an attractive strategy for synergetic breast cancer therapy due to their complementary mechanisms. In this work, a core-shell nanocarrier coated by cationic albumin was developed to simultaneously deliver miRNA-34a and docetaxel (DTX) into breast cancer cells for improved therapeutic effect. The co-delivery nanocarriers showed a spherical morphology with an average particle size of 183.9 nm, and they efficiently protected miRNA-34a from degradation by RNase and serum. Importantly, the nanocarriers entered the cytosol via a caveolae-mediated pathway without entrapment in endosomes/lysosomes, thus improving the utilization of the cargo. In vitro, the co-delivery nanocarriers suppressed the expression of anti-apoptosis gene Bcl-2 at both transcription and protein levels, inhibited tumor cell migration and efficiently induced cell apoptosis and cytotoxicity. In vivo, the co-delivery nanocarriers prolonged the blood circulation of DTX, enhanced tumor accumulation of the cargo and significantly inhibited tumor growth and metastasis in 4T1-tumor bearing mice models. Taken together, the present nanocarrier co-loading with DTX and miRNA-34a is a new nanoplatform for the combination of insoluble drugs and gene/protein drugs and provides a promising strategy for the treatment of metastatic breast cancer.

Sulfaguanidine cocrystals: Synthesis, structural characterization and their antibacterial and hemolytic analysis.

PubMed

Abidi, Syed Sibte Asghar; Azim, Yasser; Khan, Shahper Nazeer; Khan, Asad U

2018-02-05

Sulfaguanidine (SG), belongs to the class of sulfonamide drug used as an effective antibiotic. In the present work, using crystal engineering approach two novel cocrystals of SG were synthesized (SG-TBA and SG-PT) with thiobarbutaric acid (TBA) and 1,10-phenanthroline (PT), characterized by solid state techniques viz., powder X-ray diffraction (PXRD), fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and the crystal structures were determined by single crystal X-ray diffraction studies. A comparative antibacterial activity and hemolytic potential was done on SG drug, coformers and their cocrystals. The tested cocrystals formulations showed almost two fold higher antibacterial activity against the tested strains of bacteria Gram-positive bacteria (S. mutans and E. faecalis) and Gram-negative bacteria (E. coli, K. pneumonia and E. clocae) over SG alone and their coformers. Cocrystal SG-TBA showed better antibacterial activity and reduced hemolysis, thereby, reduced cytotoxicity than SG-PT. Copyright © 2017 Elsevier B.V. All rights reserved.

Sentinel case of group A beta-hemolytic streptococcus causing constrictive pericarditis presenting as hypogammaglobulinemia.

PubMed

Ahmadian, Homayoun R; Tankersley, Michael; Otto, Hans

2011-05-01

This is a unique case of a previously healthy 7-year-old boy, which highlights the importance of considering immunodeficiency when a rare infection occurs. In the following case report, the patient develops constrictive pericarditis secondary to group A beta-hemolytic streptococcal infection. As a result of this infection, we speculate that he develops hypogammaglobulinemia secondary to the documented association between constrictive pericarditis and intestinal lymphangiectasia because an extensive work-up for a primary immunodeficiency was negative. This is the first case ever to present constrictive pericarditis because of group A beta-hemolytic streptococcal infection.

Auto immune hemolytic anemia in a child precipitated by chicken pox.

PubMed

Billoo, Samina Shamim; Jamalvi, Syed Waseem

2008-05-01

Auto Immune Hemolytic Anemia (AIHA) is a rare entity in children. We report a case of an adolescent girl with AIHA, which was precipitated by chicken pox. Clinical course over 3 years, till remission is described.

Two new glucose 6-phosphate dehydrogenase variants associated with congenital nonspherocytic hemolytic anemia found in Japan: GD(-) Tokushima and GD(-) Tokyo.

PubMed

Miwa, S; Ono, J; Nakashima, K; Abe, S; Kageoka, T

1976-01-01

Two new variants of glucose 6-phosphate dehydrogenase (G6PD) deficiency associated with chronic nonspherocytic hemolytic anemia were discovered in Japan. Gd(-) Tokushima was found in a 17-years-old male whose erythrocytes contained 4.4% of normal enzyme activity. Partially purified enzyme revealed a main band of normal electrophoretic mobility with additional two minor bands of different mobility; normal Km G6P, and Km NADP five-to sixfold higher than normal; normal utilization of 2-deoxy-G6P, galactose-6P, and deamino-NADP; marked thermal instability; a normal pH curve; and normal Ki NADPH. The hemolytic anemia was moderate to severe. Gd(-) Tokyo was characterized from a 15-year-old male who had chronic nonspherocytic hemolytic anemia of mild degree. The erythrocytes contained 3% of normal enzyme activity, and partially purified enzyme revealed slow electrophoretic mobility (90% of normal for both a tris-hydrochloride buffer system and a tris-EDTA-borate buffer system, and 70% of normal for a phosphate buffer system); normal Km G6P and Km NADP; normal utilization of 2-deoxy-G6P, galactose-6P, and deamino-NADP; greatly increased thermal instability; a normal pH curve; and normal Ki NADPH. These two variants are clearly different from hitherto described G6PD variants, including the Japanese variants Gd(-) Heian and Gd(-) Kyoto. The mothers of both Gd(-) Tokushima and Gd(-) Tokoyo were found to be heterozygote by an ascorbate-cyanide test.

Preparation and Investigation of Amphiphilic Block Copolymers/Fullerene Nanocomposites as Nanocarriers for Hydrophobic Drug.

PubMed

Tan, Qinggang; Chu, Yanyan; Bie, Min; Wang, Zihao; Xu, Xiaoyan

2017-02-16

Biopolymer/inorganic material nanocomposites have attracted increasing interest as nanocarriers for delivering drugs owing to the combined advantages of both biopolymer and inorganic materials. Here, amphiphilic block copolymer/fullerene nanocomposites were prepared as nanocarriers for hydrophobic drug by incorporation of C60 in the core of methoxy polyethylene glycol-poly(d,l-lactic acid) (MPEG-PDLLA) micelles. The structure and morphology of MPEG-PDLLA/C60 nanocomposites were characterized using transmission electron microscopy, dynamic light scattering, high-resolution transmission electron microscopy, and thermal gravimetric analysis. It was found that the moderate amount of spherical C60 incorporated in the MPEG-PDLLA micelles may cause an increase in the molecular chain space of PDLLA segments in the vicinity of C60 and, thus, produce a larger cargo space to increase drug entrapment and accelerate the drug release from nanocomposites. Furthermore, sufficient additions of C60 perhaps resulted in an aggregation of C60 within the micelles that decreased the drug entrapment and produced a steric hindrance for DOX released from the nanocomposites. The results obtained provide fundamental insights into the understanding of the role of C60 in adjusting the drug loading and release of amphiphilic copolymer micelles and further demonstrate the future potential of the MPEG-PDLLA/C60 nanocomposites used as nanocarriers for controlled drug-delivery applications.

Iron-Regulated Phospholipase C Activity Contributes to the Cytolytic Activity and Virulence of Acinetobacter baumannii

PubMed Central

Fiester, Steven E.; Schmidt, Robert E.; Beckett, Amber C.; Ticak, Tomislav; Carrier, Mary V.; Ghosh, Rajarshi; Ohneck, Emily J.; Metz, Maeva L.; Sellin Jeffries, Marlo K.; Actis, Luis A.

2016-01-01

Acinetobacter baumannii is an opportunistic Gram-negative pathogen that causes a wide range of infections including pneumonia, septicemia, necrotizing fasciitis and severe wound and urinary tract infections. Analysis of A. baumannii representative strains grown in Chelex 100-treated medium for hemolytic activity demonstrated that this pathogen is increasingly hemolytic to sheep, human and horse erythrocytes, which interestingly contain increasing amounts of phosphatidylcholine in their membranes. Bioinformatic, genetic and functional analyses of 19 A. baumannii isolates showed that the genomes of each strain contained two phosphatidylcholine-specific phospholipase C (PC-PLC) genes, which were named plc1 and plc2. Accordingly, all of these strains were significantly hemolytic to horse erythrocytes and their culture supernatants tested positive for PC-PLC activity. Further analyses showed that the transcriptional expression of plc1 and plc2 and the production of phospholipase and thus hemolytic activity increased when bacteria were cultured under iron-chelation as compared to iron-rich conditions. Testing of the A. baumannii ATCC 19606T plc1::aph-FRT and plc2::aph isogenic insertion derivatives showed that these mutants had a significantly reduced PC-PLC activity as compared to the parental strain, while testing of plc1::ermAM/plc2::aph demonstrated that this double PC-PLC isogenic mutant expressed significantly reduced cytolytic and hemolytic activity. Interestingly, only plc1 was shown to contribute significantly to A. baumannii virulence using the Galleria mellonella infection model. Taken together, our data demonstrate that both PLC1 and PLC2, which have diverged from a common ancestor, play a concerted role in hemolytic and cytolytic activities; although PLC1 seems to play a more critical role in the virulence of A. baumannii when tested in an invertebrate model. These activities would provide access to intracellular iron stores this pathogen could use during

Multimodal magnetic nano-carriers for cancer treatment: Challenges and advancements

NASA Astrophysics Data System (ADS)

Aadinath, W.; Ghosh, Triroopa; Anandharamakrishnan, C.

2016-03-01

Iron oxide nanoparticles (IONPs) have been a propitious topic for cancer treatment in recent years because of its multifunctional theranostic applications under magnetic field. Two such widely used applications in cancer biology are gradient magnetic field guided targeting and alternative magnetic field (AMF) induced local hyperthermia. Gradient magnetic field guided targeting is a mode of active targeting of therapeutics conjugated with iron oxide nanoparticles. These particles also dissipate heat in presence of AMF which causes thermal injury to the cells of interest, for example tumour cells and subsequent death. Clinical trials divulge the feasibility of such magnetic nano-carrier as a promising candidate in cancer biology. However, these techniques need further investigations to curtail certain limitations manifested. Recent progresses in response have shrunken the barricade to certain extent. In this context, principles, challenges associated with these applications and recent efforts made in response will be discussed.

Co-formulation of P-glycoprotein Substrate and Inhibitor in Nanocarriers: An Emerging Strategy for Cancer Chemotherapy.

PubMed

Saneja, Ankit; Dubey, Ravindra Dhar; Alam, Noor; Khare, Vaibhav; Gupta, Prem N

2014-01-01

Scientific community is striving to understand the role of P-glycoprotein (P-gp) in drug discovery programs due to its impact on pharmacokinetic and multi-drug resistance (MDR) of anticancer drugs. A number of efforts to resolve the crystal structure and understanding the mechanism of P-gp mediated efflux have been made. Several generations of Pgp inhibitors have been developed to tackle this multi-specific efflux protein. Unfortunately, these inhibitors lack selectivity, exhibit poor solubility and severe pharmacokinetic interactions restricting their clinical use. The nanocarrier drug delivery systems (NDDS) are receiving increasing attention for P-gp modulating activity of pharmaceutical excipients which are used in their fabrication. In addition, NDDS can enhance the solubility and exhibited ability to bypass P-gp mediated efflux. The co-formulation of P-gp inhibitors and substrate anticancer drugs in single drug delivery system offers the advantage of bypassing P-gp mediated drug efflux as well as inhibiting the P-gp. Moreover, severe pharmacokinetic interactions between P-gp inhibitor and substrate anticancer drugs could be avoided by using this strategy. In this article we describe the co-formulation strategies using nanocarriers for modulation of pharmacokinetics as well as multi-drug resistance of anticancer drugs along with the challenges in this area.

pH-sensitive nanocarrier based on gold/silver core-shell nanoparticles decorated multi-walled carbon manotubes for tracing drug release in living cells.

PubMed

Chen, Peng; Wang, Zhuyuan; Zong, Shenfei; Zhu, Dan; Chen, Hui; Zhang, Yizhi; Wu, Lei; Cui, Yiping

2016-01-15

We fabricate a multifunctional nanocarrier based on multi-walled carbon nanotubes (MWCNTs) decorated with gold/silver core-shell nanoparticles (Au@Ag NPs) and fluorescein isothiocyanate (FITC) for tracking the intracellular drug release process. In the demonstrated nanocarrier, the Au@Ag NPs adsorbed on the surface of MWCNTs were labeled with the pH-dependent SERS reporter 4-Mercaptobenzoic acid (4MBA) for SERS based pH sensing. FITC was conjugated on MWCNTs to provide fluorescence signal for tracing the MWCNTs. Fluorescent doxorubicin (DOX) was used as the model drug which can be loaded onto MWCNTs via π-π stacking and released from the MWCNTs under acidic condition. By detecting the SERS spectrum of 4MBA, the pH value around the nanocarrier could be monitored. Besides, by tracing the fluorescence of FITC and DOX, we can also investigate the drug release process in cells. Experimental results show that the proposed nanocarrier retained a well pH-sensitive performance in living cells, and the DOX detached from MWCNTs inside the lysosomes and entered into the cytoplasm with the MWCNTs being left in lysosomes. To further investigate the drug release dynamics, 2-D color-gradient pH mapping were plotted, which were calculated from the SERS spectra of 4MBA. The detailed release process and carrier distribution have been recorded as environmental pH changes during cell endocytosis. Furthermore, we also confirmed that the proposed nanocarrier has a good biocompatibility. It indicates that the designed nanocarrier have a great potential in intraceable drug delivery, cancer cells imaging and pH monitoring. Copyright © 2015 Elsevier B.V. All rights reserved.

ADAMTS13 Gene Mutations in Children with Hemolytic Uremic Syndrome

PubMed Central

Choi, Hyoung Soo; Cheong, Hae Il; Kim, Nam Keun

2011-01-01

We investigated ADAMTS13 activity as well as the ADAMTS13 gene mutation in children with hemolytic uremic syndrome (HUS). Eighteen patients, including 6 diarrhea-negative (D-HUS) and 12 diarrhea-associated HUS (D+HUS) patients, were evaluated. The extent of von Willebrand factor (VWF) degradation was assayed by multimer analysis, and all exons of the ADAMTS13 gene were PCR-amplified using Taq DNA polymerase. The median and range for plasma activity of ADAMTS13 in 6 D-HUS and 12 D+HUS patients were 71.8% (22.8-94.1%) and 84.9% (37.9-119.9%), respectively, which were not statistically significantly different from the control group (86.4%, 34.2-112.3%) (p>0.05). Five ADAMTS13 gene mutations, including 2 novel mutations [1584+2T>A, 3941C>T (S1314L)] and 3 polymorphisms (Q448E, P475S, S903L), were found in 2 D-HUS and one D+HUS patients, which were not associated with deficiency of ADAMTS13 activity. Whether these mutations without reduced ADAMTS13 activity are innocent bystanders or predisposing factors in HUS remains unanswered. PMID:21488199

Polymer Self-Assembled Nanostructures as Innovative Drug Nanocarrier Platforms.

PubMed

Pippa, Natassa; Pispas, Stergios; Demetzos, Costas

2016-01-01

Polymer self-assembled nanostructures are used in pharmaceutical sciences as bioactive molecules' delivery systems for therapeutic and diagnostic purposes. Micelles, polyelectrolyte complexes, polymersomes, polymeric nanoparticles, nanogels and polymer grafted liposomes represent delivery vehicles that are marketed and/or under clinical development, as drug formulations. In this mini-review, these, recently appeared in the literature, innovative polymer drug nanocarrier platforms are discussed, starting from their technological development in the laboratory to their potential clinical use, through studies of their biophysics, thermodynamics, physical behavior, morphology, bio-mimicry, therapeutic efficacy and safety. The properties of an ideal drug delivery system are the structural control over size and shape of drug or imaging agent cargo/domain, biocompatibility, nontoxic polymer/ pendant functionality and the precise, nanoscale container and/or scaffolding properties with high drug or imaging agent capacity features. Self-assembled polymer nanostructures exhibit all these properties and could be considered as ideal drug nanocarriers through control of their size, structure and morphology, with the aid of a large variety of parameters, in vitro and in vivo. These modern trends reside at the interface of soft matter self-assembly and pharmaceutical sciences and the technologies for health. Great advantages related to basic science and applications are expected by understanding the self-assembly behavior of these polymeric nanotechnological drug delivery systems, created through bio-inspiration and biomimicry and have potential utilization into clinical applications.

[Analysis of Correlation between IgG Titer of Pregnant Women and Neonatal Hemolytic Complications of Different Blood Groups].

PubMed

Ye, Hai-Hui; Huang, Hong-Hai; Wang, Xiao-Lin; Pi, You-Jun

2017-10-01

To study the relationship between IgG titer of pregnant women and hemolytic disease of newborn(HDN) with different blood groups. Four hundred pregnant women, including pregnant women with type O blood, were selected from May 2014 to January 2015 in our hospital for inspection and a couple of different blood groups, the IgG titer of pregnant women were detected in the inspection process. According to neonatal HDN, newborns were divided into 2 groups: HDN group(85 cases) and non-HDN group(315 cases). The incidence of postpartum neonatal hemolytic disease was tracked and the correlation of IgG titers with HDN were systematically analyzed. In the production and inspection process, the IgG titer in pregnant women was divided into <1:64, 1:64, 1:128, 1:256 and greater than or equal to 1:512 five groups. the comparison of HDN incidence rate in 4 groups of IgG titer >64 and IgG titer <1:64 group showed that the prevalence of ABO hemolytic disease of newborn were 96.9%, 79.6%, 63, 7% and 28.8%, there was a certain correlation of pregnant women IgG titers with ABO hemolytic disease of the newborn, that is, with the increase of IgG titer, the incidence of hemolytic disease of newborns increased in certain degree (r=0.8832), the risk in 4 groups of neonatal HDN was higher than that in IgG titer <1:64 of IgG titer >64 HDN group. There is a certain corelation between prevalence of ABO-HDN and IgG titer of pregnant women. For these pregnant women, the control of the pregnant women IgG titer has a positive clinical significance to reduce the incidence of hemolytic disease of the newborn.

Triggered release of model drug from AuNP-doped BSA nanocarriers in hair follicles using IRA radiation.

PubMed

Lademann, J; Richter, H; Knorr, F; Patzelt, A; Darvin, M E; Rühl, E; Cheung, K Y; Lai, K K; Renneberg, R; Mak, W C

2016-01-01

Recent advances in the field of dermatotherapy have resulted in research efforts focusing on the use of particle-based drug delivery systems for the stimuli-responsive release of drugs in the skin and skin appendages, i.e. hair follicles and sebaceous glands. However, effective and innocuous trigger mechanisms which result in the release of the drugs from the nanocarriers upon reaching the target structures are still lacking. For the first time, the present study demonstrated the photo-activated release of the model drug fluorescein isothiocyanate (FITC) from topically applied gold nanoparticle-doped bovine serum albumin (AuNPs-doped BSA) particles (approx. 545nm) using water-filtered infrared A (IRA) radiation in the hair follicles of an ex vivo porcine skin model. The IRA radiation-induced plasmonic heating of the AuNPs results in the partial decomposition or opening of the albumin particles and release the model drug, while control particles without AuNPs show insignificant release. The results demonstrate the feasibility of using IRA radiation to induce release of encapsulated drugs from plasmonic nanocarriers for the targeting of follicular structures. However, the risk of radiation-induced skin damage subsequent to repeated applications of high infrared dosages may be significant. Future studies should aim at determining the suitability of lower infrared A dosages, such as for medical treatment regimens which may necessitate repeated exposure to therapeutics. Follicular targeting using nanocarriers is of increasing importance in the prophylaxis and treatment of dermatological or other diseases. For the first time, the present study demonstrated the photo-activated release of the model drug fluorescein isothiocyanate (FITC) from topically applied gold nanoparticle-doped bovine serum albumin (AuNPs-doped BSA) particles using water-filtered infrared A (IRA) radiation in the hair follicles of an ex vivo porcine skin model. The results demonstrate the feasibility

Protection of bronze artefacts through polymeric coatings based on nanocarriers filled with corrosion inhibitors

NASA Astrophysics Data System (ADS)

de Luna, Martina Salzano; Buonocore, Giovanna; Di Carlo, Gabriella; Giuliani, Chiara; Ingo, Gabriel M.; Lavorgna, Marino

2016-05-01

Protective coatings based on polymers synthesized from renewable sources (chitosan or an amorphous vinyl alcohol based polymer) have been prepared for the protection of bronze artifacts from corrosion. Besides acting as an effective barrier against corrosive species present in the environment, the efficiency of the coatings has been improved by adding corrosion inhibitor compounds (benzotriazole or mercaptobenzothiazole) to the formulations. The liquid medium of the formulations has been carefully selected looking at maximizing the wettability on the bronze substrate and optimizing the solvent evaporation rate. The minimum amount of inhibitor compounds has been optimized by performing accelerated corrosion tests on coated bronze substrates. The inhibitors have been directly dissolved in the coating-forming solutions and/or introduced by means of nanocarriers, which allow to control the release kinetics. The free dissolved inhibitor molecules immediately provide a sufficient protection against corrosion. On the other hand, the inhibitor molecules contained in the nanocarriers serve as long-term reservoir, which can be activated by external corrosion-related stimuli in case of particularly severe conditions. Particular attention has been paid to other features which affect the coating performances. Specifically, the adhesion of the protective polymer layer to the bronze substrate has been assessed, as well as its permeability properties and transparency, the latter being a fundamental feature of protective coating for cultural heritages. Finally, the protective efficiency of the produced smart coatings has been assessed through accelerated corrosion tests.

Differential intra-endothelial delivery of polymer nanocarriers targeted to distinct PECAM-1 epitopes

PubMed Central

Garnacho, Carmen; Albelda, Steven M.; Muzykantov, Vladimir R.; Muro, Silvia

2008-01-01

Coupling drug carriers to antibodies for targeting endothelial cells (ECs) may improve treatment of vascular and pulmonary diseases. Selecting antibodies that deliver carriers to the cell surface or intracellularly may further optimize specifcity of interventions. We studied antibody-directed targeting of nanocarriers to platelet–endothelial cell adhesion molecule (PECAM)-1, an endothelial glycoprotein containing 6 Ig-like extracellular domains. PECAM-1 antibodies bind to ECs without internalization, but ECs internalize by endocytosis nanocarriers carrying multiple copies of anti-PECAM (anti-PECAM/NCs). To determine whether binding and intracellular transport of anti-PECAM/NCs depend on the epitope engaged, we targeted five PECAM-1 epitopes: mAb35, mAb37 and mAb62 (membrane-distal Ig domain 1), mAbGi34 (Ig domains 2/3), and mAb4G6 (membrane-proximal Ig domain 6). The antibodies bound to ECs regardless of the epitope proximity to the plasmalemma, whereas 130 nm diameter nanocarriers only targeted effectively distal domains (mAb4G6/NCs did not bind to ECs). ECs internalized mAb35, mAb62, and mAbGi34 carriers regardless of their size (0.13 to 5 µm diameter), yet they did not internalize mAb37/NCs. After internalization, mAb62/NCs trafficked to lysosomes within 2–3 h, whereas mAb35/NCs had prolonged residence in pre-lysosomal vesicles. Therefore, endothelial binding, endocytosis, and intracellular transport of anti-PECAM/NCs are epitope-specific. This paradigm will guide the design of endothelial drug delivery systems providing specific cellular localizations. PMID:18606202

Multifunctionalized polyethyleneimine-based nanocarriers for gene and chemotherapeutic drug combination therapy through one-step assembly strategy

PubMed Central

Wang, Tianqi; Zhang, Bo; Liu, Chunxi; Zhang, Na

2017-01-01

Gene therapy combined with chemotherapy to achieve synergistic therapeutic effects has been a hot topic in recent years. In this project, the human tumor necrosis factor-related apoptosis-inducing ligand-encoding plasmid gene (TRAIL) and doxorubicin (Dox)-coloaded multi-functional nanocarrier was constructed based on the theory of circulation, accumulation, internalization, and release. Briefly, polyethyleneimine (PEI) was selected as skeleton material to synthesize PEI–polyethylene glycol (PEG)–TAT (PPT). Dox was conjugated to PEI using C6-succinimidyl 6-hydrazinonicotinate acetone hydrazone (C6-SANH), and a pH-sensitive Dox-PEI (DP) conjugate was obtained. Then, intracellular cationic pH-sensitive cellular assistant PPT and DP were mixed to condense TRAIL, and TRAIL–Dox coloaded PPT/DP/TRAIL (PDT) nanocarriers were obtained by one-step assembly. TRAIL was completely condensed by DP or PPT when mass ratios (DP/PPT to TRAIL) were up to 100:64, which indicated that DP and PPT could be mixed at any ratio for TRAIL condensation. The intracellular uptake rate of PDT was enhanced (P<0.05) when the contents of PPT in PPT+DP increased from 0 to 30%. Free Dox and TRAIL-loaded nanocarriers (PPT/C6-SANH-PEI/TRAIL [PCT]) were selected as controls to verify the synergistic antitumor effects of PDT. Compared with free TRAIL, TRAIL-protein expression was upregulated by PDT and PCT on Western blotting assays. The in vitro cytotoxicity of PDT was significantly enhanced compared to free Dox and PCT (P<0.01). Furthermore, murine PDT nanocarriers showed higher in vivo antitumor ability than both the Dox group (P<0.05) and the murine PCT group (P<0.05). These results indicated that the TRAIL + Dox synergistic antitumor effect could be achieved by PDT, which paves the way to gene–drug combination therapy for cancer. PMID:29263663

Virus scaffolds as enzyme nano-carriers.

PubMed

Cardinale, Daniela; Carette, Noëlle; Michon, Thierry

2012-07-01

The cooperative organization of enzymes by cells is a key feature for the efficiency of living systems. In the field of nanotechnologies, effort currently aims at mimicking this natural organization. Nanoscale resolution and high-registration alignment are necessary to control enzyme distribution in nano-containers or on the surface of solid supports. Virus capsid self-assembly is driven by precise supramolecular combinations of protein monomers, which have made them attractive building blocks to engineer enzyme nano-carriers (ENCs). We discuss some examples of what in our opinion constitute the latest advances in the use of plant viruses, bacteriophages and virus-like particles (VLPs) as nano-scaffolds for enzyme selection, enzyme confinement and patterning, phage therapy, raw material processing, and single molecule enzyme kinetics studies. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Congenital hemolytic anemia due to glucose-6-phosphate dehydrogenase deficiency].

PubMed

Mura, M; Saidi, R; Wolf, A; Moalic, J L; Oliver, M

2009-12-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzyme defect with a wide range of clinical manifestations that can be severe. A variety of factors including many medications can induce hemolytic episodes. Screening for G6PD deficiency is required before use of some drugs especially primaquine or dapsone.

Self-assembled stable sponge-type nanocarries for Brucea javanica oil delivery.

PubMed

Zou, Aihua; Li, Yawen; Chen, Yiyin; Angelova, Angelina; Garamus, Vasil M; Li, Na; Drechsler, Markus; Angelov, Borislav; Gong, Yabin

2017-05-01

Sponge-type nanocarriers (spongosomes) are produced upon dispersion of a liquid crystalline sponge phase formed by self-assembly of an amphiphilic lipid in excess aqueous phase. The inner organization of the spongosomes is built-up by randomly ordered bicontinuous lipid membranes and their surfaces are stabilized by alginate chains providing stealth properties and colloidal stability. The present study elaborates spongosomes for improved encapsulation of Brucea javanica oil (BJO), a traditional Chinese medicine that may strongly inhibit proliferation and metastasis of various cancers. The inner structural organization and the morphology characteristics of BJO-loaded nanocarriers at varying quantities of BJO were determined by cryogenic transmission electron microscopy (Cryo-TEM), small angle X-ray scattering (SAXS) and dynamic light scattering (DLS). Additionally, the drug loading and drug release profiles for BJO-loaded spongosome systems also were determined. We found that the sponge-type liquid crystalline lipid membrane organization provides encapsulation efficiency rate of BJO as high as 90%. In vitro cytotoxicity and apoptosis study of BJO spongosome nanoparticles with A549 cells demonstrated enhanced anti-tumor efficiency. These results suggest potential clinical applications of the obtained safe spongosome formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Nanocarriers for the treatment of glioblastoma multiforme: Current state-of-the-art.

PubMed

Karim, Reatul; Palazzo, Claudio; Evrard, Brigitte; Piel, Geraldine

2016-04-10

Glioblastoma multiforme, a grade IV glioma, is the most frequently occurring and invasive primary tumor of the central nervous system, which causes about 4% of cancer-associated-deaths, making it one of the most fatal cancers. With present treatments, using state-of-the-art technologies, the median survival is about 14 months and 2 year survival rate is merely 3-5%. Hence, novel therapeutic approaches are urgently necessary. However, most drug molecules are not able to cross the blood-brain barrier, which is one of the major difficulties in glioblastoma treatment. This review describes the features of blood-brain barrier, and its anatomical changes with different stages of tumor growth. Moreover, various strategies to improve brain drug delivery i.e. tight junction opening, chemical modification of the drug, efflux transporter inhibition, convection-enhanced delivery, craniotomy-based drug delivery and drug delivery nanosystems are discussed. Nanocarriers are one of the highly potential drug transport systems that have gained huge research focus over the last few decades for site specific drug delivery, including drug delivery to the brain. Properly designed nanocolloids are capable to cross the blood-brain barrier and specifically deliver the drug in the brain tumor tissue. They can carry both hydrophilic and hydrophobic drugs, protect them from degradation, release the drug for sustained period, significantly improve the plasma circulation half-life and reduce toxic effects. Among various nanocarriers, liposomes, polymeric nanoparticles and lipid nanocapsules are the most widely studied, and are discussed in this review. For each type of nanocarrier, a general discussion describing their composition, characteristics, types and various uses is followed by their specific application to glioblastoma treatment. Moreover, some of the main challenges regarding toxicity and standardized evaluation techniques are narrated in brief. Copyright © 2016 Elsevier B.V. All

Encapsulation of a proteasome inhibitor with gold-polysaccharide nanocarriers

NASA Astrophysics Data System (ADS)

Coelho, Sílvia Castro; Rocha, Sandra; Sampaio, Paula; Pereira, Maria Carmo; Coelho, Manuel A. N.

2014-04-01

Organic-inorganic hybrid nanoparticles are potential effective systems for drug delivery in cancer therapy and diagnosis. Chitosan-gum arabic with entrapped gold nanoparticles were developed as a carrier for an anticancer drug bortezomib. The nanosystem was designed to enhance the proteasome inhibitor activity in pancreatic cell lines, S2-013 and hTERT-HPNE. The hydrodynamic diameter of chitosan-gum arabic-gold nanoparticles loaded with bortezomib is around 330 nm. Laser scanning confocal microscopy images show the uptake of the gold nanoparticle/bortezomib encapsulated in chitosan-gum arabic matrix and the fast internalization of these nano combinations into pancreatic cells. Cytotoxic assays assessed that positively charged nanosystems reduce the cell growth and cell proliferation of S2-013s, but the same effect was not observed in cytotoxic response in hTERT-HPNE cells. The outcomes of this study demonstrate the capacity of chitosan-gum arabic nanocarriers to deliver gold nanoparticles/anticancer drug and to increase the permeation and retention effect in S2-013 cells and minimize drug side effects in HPNE cells.

Tweaking Dendrimers and Dendritic Nanoparticles for Controlled Nano-bio Interactions: Potential Nanocarriers for Improved Cancer Targeting

PubMed Central

Bugno, Jason; Hsu, Hao-Jui; Hong, Seungpyo

2016-01-01

Nanoparticles have shown great promise in the treatment of cancer, with a demonstrated potential in targeted drug delivery. Among a myriad of nanocarriers that have been recently developed, dendrimers have attracted a great deal of scientific interests due to their unique chemical and structural properties that allow for precise engineering of their characteristics. Despite this, the clinical translation of dendrimers has been hindered due to their drawbacks, such as scale-up issues, rapid systemic elimination, inefficient tumor accumulation, and limited drug loading. In order to overcome these limitations, a series of reengineered dendrimers have been recently introduced using various approaches, including: i) modifications of structure and surfaces; ii) integration with linear polymers; and iii) hybridization with other types of nanocarriers. Chemical modifications and surface engineering have tailored dendrimers to improve their pharmacokinetics and tissue permeation. Copolymerization of dendritic polymers with linear polymers has resulted in various amphiphilic copolymers with self-assembly capabilities and improved drug loading efficiencies. Hybridization with other nanocarriers integrates advantageous characteristics of both systems, which includes prolonged plasma circulation times and enhanced tumor targeting. This review provides a comprehensive summary of the newly emerging drug delivery systems that involve reengineering of dendrimers in an effort to precisely control their nano-bio interactions, mitigating their inherent weaknesses. PMID:26453160

Optical, colloidal and biological properties of up-converting nanoparticles embedded in polyester nanocarriers

NASA Astrophysics Data System (ADS)

Wawrzyńczyk, Dominika; Kulbacka, Julita; Bazylińska, Urszula

2017-08-01

We have investigated the change in optical properties and biocompatibility of up-converting NaYF4 nanoparticles (NPs) upon encapsulation inside the polyester nanocarriers (NCs) stabilized by Crempophor RH40 (CRH40), poly(D,L-lactide) (PLA), Pluronic P123 (P123). NaYF4:Er3+,Yb3+ NPs showed intense green and red emission, and upon encapsulation the increase of red band in respect to green one was observed, with no luminescence lifetime shortening. Obtained NCs showed prolonged colloidal stability and protective effect of the polymer shell simultaneously preserving the high emission efficiency of nanoparticles embedded within the silicon oil (SO) core. Based on emission spectra, kinetic measurements and cytotoxicity studies upon human malignant melanoma Me45 cell line we have shown the advantages of using polyester NCs as containers for the up-converting NPs. Due to the possibility of co-encapsulation of photosensitizers the obtained nanocarriers showed potential for application in theranostics.

Metronomic chemotherapy and nanocarrier platforms.

PubMed

Abu Lila, Amr S; Ishida, Tatsuhiro

2017-08-01

The therapeutic concept of administering chemotherapeutic agents continuously at lower doses, relative to the maximum tolerated dose (MTD) without drug-free breaks over extended periods -known as "metronomic chemotherapy"- is a promising approach for anti-angiogenic cancer therapy. In comparison with MTD chemotherapy regimens, metronomic chemotherapy has demonstrated reduced toxicity. However, as a monotherapy, metronomic chemotherapy has failed to provide convincing results in clinical trials. Therapeutic approaches including combining the anti-angiogenic "metronomic" therapy with conventional radio-/chemo-therapy and/or targeted delivery of chemotherapeutic agents to tumor tissues via their encapsulation with nanocarrier-based platforms have proven to potentiate the overall therapeutic outcomes. In this review, therefore, we focused on the mutual contribution made by nanoscale drug delivery platforms to the therapeutic efficacy of metronomic-based chemotherapy. In addition, the influence that the dosing schedule has on the overall therapeutic efficacy of metronomic chemotherapy is discussed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Water-soluble pH-responsive dendritic core-shell nanocarriers for polar dyes based on poly(ethylene imine).

PubMed

Xu, Shangjie; Luo, Ying; Haag, Rainer

2007-08-07

A simple general synthetic concept to build dendritic core-shell architectures with pH-labile linkers based on hyperbranched PEI cores and biocompatible PEG shells is presented. Using these dendritic core-shell architectures as nanocarriers, the encapsulation and transport of polar dyes of different sizes is studied. The results show that the acid-labile nanocarriers exhibit much higher transport capacities for dyes than unfunctionalized hyperbranched PEI. The cleavage of imine bonds and controlled release of the polar dyes revealed that weak acidic condition (pH approximately 5.0) could cleave the imine bonds linker and release the dyes up to five times faster than neutral conditions (pH = 7.4).

[Hemolytic anemia caused by graft-versus-host reaction in ABO-nonidentical renal transplants from blood group O donors].

PubMed

Peces, R; Díaz Corte, C; Navascués, R A

2001-01-01

Acute hemolytic anemia is one of the side effects associated with cyclosporin and tacrolimus therapy, and three mechanisms have been described to account for hemolytic anemia in patients receiving these drugs: drug induced hemolysis, autoimmune hemolysis and alloimmune hemolysis resulting from donor lymphocytes derived from the allograft (passenger lymphocyte syndrome). We report four cases of renal transplant recipients who developed alloimmune hemolytic anemia due to minor ABO incompatibility while under treatment with cyclosporin (two) and tacrolimus (two). The anti-erythrocyte antibodies responsible for hemolysis were of the IgG isotype and showed anti-A or anti-B specificity. These findings suggest that the hemolysis could be related to alloantibodies derived from the clonal development of donor B lymphocytes in the recipients (microchimerism). In summary, hemolytic anemia due to ABO-minor incompatibility occurs infrequently after renal transplantation. Risks are higher for patients A, B or AB blood group receiving an O blood group graft under treatment with cyclosporin or tacrolimus. Follow-up of these patients is warranted for the early detection and optimal management may be achieved by reduction of immunosuppression and change to mycophenolate mofetil.

Multi-branched ionic liquid-chitosan as a smart and biocompatible nano-vehicle for combination chemotherapy with stealth and targeted properties.

PubMed

Rahimi, Mahdi; Shafiei-Irannejad, Vahid; D Safa, Kazem; Salehi, Roya

2018-09-15

A possible approach for clinical cancer treatment is combination chemotherapy. To address this issue, many anticancer agents have been used simultaneously to achieve synergistic effects with the different mechanism of actions, however, their toxic side effects are still a big challenge. In this study, a smart, biocompatible, magnetic nanocarrier composed of multi-branched ionic liquid-chitosan grafted mPEG was designed and used for targeted multidrug delivery of DOX and MTX as model anticancer agents to MCF7 breast cancer cells. The results of hemolysis assay on human red blood cells and cytotoxicity studies indicated that blank nanocarrier has no significant hemolytic and cytotoxic effects in MCF7 cells as observed in the results of MTT assay, however, drugs-loaded nanocarrier could decrease the viability of MCF7 cells in a dose-dependent manner. To further simulate the interaction of nanocarrier with plasma proteins, the SDS-PAGE assay was performed after the nanocarrier was incubated with human plasma and the results indicated that a series of proteins were attached to the surface of nanocarrier leading protein-particle corona complex. This complex gives a stealth property as well as increasing cellular uptake process due to the presence of proteins acting as ligands for receptors in the surface of cancer cells that are suitable for drug delivery systems. The efficiency of dual-drug delivery was also confirmed by cellular uptake and DAPI staining. All these results persuade us, this nanocarrier is suitable for use in further animal studies in future investigations. Copyright © 2018 Elsevier Ltd. All rights reserved.

ATP-Responsive and Near-Infrared-Emissive Nanocarriers for Anticancer Drug Delivery and Real-Time Imaging.

PubMed

Qian, Chenggen; Chen, Yulei; Zhu, Sha; Yu, Jicheng; Zhang, Lei; Feng, Peijian; Tang, Xin; Hu, Quanyin; Sun, Wujin; Lu, Yue; Xiao, Xuanzhong; Shen, Qun-Dong; Gu, Zhen

2016-01-01

Stimuli-responsive and imaging-guided drug delivery systems hold vast promise for enhancement of therapeutic efficacy. Here we report an adenosine-5'-triphosphate (ATP)-responsive and near-infrared (NIR)-emissive conjugated polymer-based nanocarrier for the controlled release of anticancer drugs and real-time imaging. We demonstrate that the conjugated polymeric nanocarriers functionalized with phenylboronic acid tags on surface as binding sites for ATP could be converted to the water-soluble conjugated polyelectrolytes in an ATP-rich environment, which promotes the disassembly of the drug carrier and subsequent release of the cargo. In vivo studies validate that this formulation exhibits promising capability for inhibition of tumor growth. We also evaluate the metabolism process by monitoring the fluorescence signal of the conjugated polymer through the in vivo NIR imaging.

Dendritic Core-Multishell Nanocarriers in Murine Models of Healthy and Atopic Skin

NASA Astrophysics Data System (ADS)

Radbruch, Moritz; Pischon, Hannah; Ostrowski, Anja; Volz, Pierre; Brodwolf, Robert; Neumann, Falko; Unbehauen, Michael; Kleuser, Burkhard; Haag, Rainer; Ma, Nan; Alexiev, Ulrike; Mundhenk, Lars; Gruber, Achim D.

2017-01-01

Dendritic hPG-amid-C18-mPEG core-multishell nanocarriers (CMS) represent a novel class of unimolecular micelles that hold great potential as drug transporters, e.g., to facilitate topical therapy in skin diseases. Atopic dermatitis is among the most common inflammatory skin disorders with complex barrier alterations which may affect the efficacy of topical treatment.

Preservation of renal function in atypical hemolytic uremic syndrome by eculizumab: a case report.

PubMed

Giordano, Mario; Castellano, Giuseppe; Messina, Giovanni; Divella, Claretta; Bellantuono, Rosa; Puteo, Flora; Colella, Vincenzo; Depalo, Tommaso; Gesualdo, Loreto

2012-11-01

Genetic mutations in complement components are associated with the development of atypical hemolytic uremic syndrome (aHUS), a rare disease with high morbidity rate triggered by infections or unidentified factors. The uncontrolled activation of the alternative pathway of complement results in systemic endothelial damage leading to progressive development of renal failure. A previously healthy 8-month-old boy was referred to our hospital because of onset of fever, vomiting, and a single episode of nonbloody diarrhea. Acute kidney injury with preserved diuresis, hemolytic anemia, and thrombocytopenia were detected, and common protocols for management of HUS were followed without considerable improvement. The persistent low levels of complement component C3 led us to hypothesize the occurrence of aHUS. In fact, the child carried a specific mutation in complement factor H (Cfh; nonsense mutation in 3514G>T, serum levels of Cfh 138 mg/L, normal range 350-750). Given the lack of response to therapy and the occurrence of kidney failure requiring dialysis, we used eculizumab as rescue therapy, a monoclonal humanized antibody against the complement component C5. One week from the first administration, we observed a significant improvement of all clinical and laboratory parameters with complete recovery from hemodialysis, even in the presence of systemic infections. Our case report shows that complement inhibiting treatment allows the preservation of renal function and avoids disease relapses during systemic infections.

Intracellular delivery of polymeric nanocarriers: a matter of size, shape, charge, elasticity and surface composition.

PubMed

Agarwal, Rachit; Roy, Krishnendu

2013-06-01

Recent progress in drug discovery has enabled the targeting of specific intracellular molecules to achieve therapeutic effects. These next-generation therapeutics are often biologics that cannot enter cells by mere diffusion. Therefore, it is imperative that drug carriers are efficiently internalized by cells and reach specific target organelles before releasing their cargo. Nanoscale polymeric carriers are particularly suitable for such intracellular delivery. Although size and surface charge have been the most studied parameters for nanocarriers, it is now well appreciated that other properties, for example, particle shape, elasticity and surface composition, also play a critical role in their transport across physiological barriers. It is proposed that a multivariate design space that considers the interdependence of particle geometry with its mechanical and surface properties must be optimized to formulate drug nanocarriers for effective accumulation at target sites and efficient intracellular delivery.

Drug nanocarrier, the future of atopic diseases: Advanced drug delivery systems and smart management of disease.

PubMed

Shao, Mei; Hussain, Zahid; Thu, Hnin Ei; Khan, Shahzeb; Katas, Haliza; Ahmed, Tarek A; Tripathy, Minaketan; Leng, Jing; Qin, Hua-Li; Bukhari, Syed Nasir Abbas

2016-11-01

Atopic dermatitis (AD) is a chronically relapsing skin inflammatory disorder characterized by perivascular infiltration of immunoglobulin-E (IgE), T-lymphocytes and mast cells. The key pathophysiological factors causing this disease are immunological disorders and the compromised epidermal barrier integrity. Pruritus, intense itching, psychological stress, deprived physical and mental performance and sleep disturbance are the hallmark features of this dermatological complication. Preventive interventions which include educational programs, avoidance of allergens, exclusive care towards skin, and the rational selection of therapeutic regimen play key roles in the treatment of dermatosis. In last two decades, it is evident from a plethora of studies that scientific focus is being driven from conventional therapies to the advanced nanocarrier-based regimen for an effective management of AD. These nanocarriers which include polymeric nanoparticles (NPs), hydrogel NPs, liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanoemulsion, provide efficient roles for the target specific delivery of the therapeutic payload. The success of these targeted therapies is due to their pharmaceutical versatility, longer retention time at the target site, avoiding off-target effects and preventing premature degradation of the incorporated drugs. The present review was therefore aimed to summarise convincing evidence for the therapeutic superiority of advanced nanocarrier-mediated strategies over the conventional therapies used in the treatment of AD. Copyright © 2016 Elsevier B.V. All rights reserved.

Endothelial Targeting of Semi-permeable Polymer Nanocarriers for Enzyme Therapies

PubMed Central

Dziubla, Thomas D; Shuvaev, Vladimir V.; Hong, Nan Kang; Hawkins, Brian; Muniswamy, Madesh; Takano, Hajime; Simone, Eric; Nakada, Marian T.; Fisher, Aron; Albelda, Steven M.; Muzykantov, Vladimir R.

2007-01-01

The medical utility of proteins, e.g. therapeutic enzymes, is greatly restricted by their liable nature and inadequate delivery. Most therapeutic enzymes do not accumulate in their targets and are inactivated by proteases. Targeting of enzymes encapsulated into substrate-permeable Polymeric Nano-Carriers (PNC) impermeable for proteases might overcome these limitations. To test this hypothesis, we designed endothelial targeted PNC loaded with catalase, the H2O2-detoxifying enzyme, and tested if this approach protects against vascular oxidative stress, a pathological process implicated in ischemia-reperfusion and other disease conditions. Encapsulation of catalase (MW 240KD), peroxidase (MW 42kD) and xanthine oxidase (XO, MW 300 kD) into ~300nm diameter PNC composed of co-polymers of PEG-PLGA (polyethylene glycol and poly-lactic/poly-glycolic acid) was in the range ~10% for all enzymes. PNC/catalase and PNC/peroxidase were protected from external proteolysis and exerted the enzymatic activity on their PNC diffusible substrates, H2O2 and ortho-phenylendiamine, whereas activity of encapsulated XO was negligible due to polymer impermeability to the substrate. PNC targeted to platelet-endothelial cell adhesion molecule-1 delivered active encapsulated catalase to endothelial cells and protected the endothelium against oxidative stress in cell culture and animal studies. Vascular targeting of PNC-loaded detoxifying enzymes may find wide medical applications including management of oxidative stress and other toxicities. PMID:17950837

Portable microsystem integrates multifunctional dielectrophoresis manipulations and a surface stress biosensor to detect red blood cells for hemolytic anemia.

PubMed

Sang, Shengbo; Feng, Qiliang; Jian, Aoqun; Li, Huiming; Ji, Jianlong; Duan, Qianqian; Zhang, Wendong; Wang, Tao

2016-09-20

Hemolytic anemia intensity has been suggested as a vital factor for the growth of certain clinical complications of sickle cell disease. However, there is no effective and rapid diagnostic method. As a powerful platform for bio-particles testing, biosensors integrated with microfluidics offer great potential for a new generation of portable point of care systems. In this paper, we describe a novel portable microsystem consisting of a multifunctional dielectrophoresis manipulations (MDM) device and a surface stress biosensor to separate and detect red blood cells (RBCs) for diagnosis of hemolytic anemia. The peripheral circuit to power the interdigitated electrode array of the MDM device and the surface stress biosensor test platform were integrated into a portable signal system. The MDM includes a preparing region, a focusing region, and a sorting region. Simulation and experimental results show the RBCs trajectories when they are subjected to the positive DEP force, allowing the successful sorting of living/dead RBCs. Separated RBCs are then transported to the biosensor and the capacitance values resulting from the variation of surface stress were measured. The diagnosis of hemolytic anemia can be realized by detecting RBCs and the portable microsystem provides the assessment to the hemolytic anemia patient.

Hemolytic anemia caused by aortic flap and inversion of felt strip after ascending aorta replacement.

PubMed

Sakaguchi, Masayuki; Takano, Tamaki

2016-08-02

Hemolysis related to a kinked prosthetic graft or inner felt strip is a very rare complication after aortic surgery. We describe herein a case of hemolytic anemia that developed due to aortic flap of the dissection and inversion of an inner felt strip that was applied at the proximal anastomosis of a replaced ascending aorta 10 years previously. A 74-year-old woman presented with consistent hemolytic anemia 10 years after replacement of the ascending aorta to treat Stanford type A acute aortic dissection. The cause of hemolysis was attributed to mechanical injury of red blood cells at a site of stenosis caused by aortic flap of the dissection and inversion of the felt strip used for the proximal anastomosis. Repeated resection of the strip and graft replacement of the ascending aorta resolved this problem. We considered that blood flow disrupted by a jet of blood at the site of the proximal inner felt strip was the cause of severe hemolysis, we describe rare hemolytic anemia at the site of aortic flap and inverted felt strip after replacement of the ascending aorta.

Recent advances in topical delivery of proteins and peptides mediated by soft matter nanocarriers.

PubMed

Witting, Madeleine; Obst, Katja; Friess, Wolfgang; Hedtrich, Sarah

2015-11-01

Proteins and peptides are increasingly important therapeutics for the treatment of severe and complex diseases like cancer or autoimmune diseases due to their high specificity and potency. Their unique structure and labile physicochemical properties, however, require special attention in the production and formulation process as well as during administration. Aside from conventional systemic injections, the topical application of proteins and peptides is an appealing alternative due to its non-invasive nature and thus high acceptance by patients. For this approach, soft matter nanocarriers are interesting delivery systems which offer beneficial properties such as high biocompatibility, easiness of modifications, as well as targeted drug delivery and release. This review aims to highlight and discuss technological developments in the field of soft matter nanocarriers for the delivery of proteins and peptides via the skin, the eye, the nose, and the lung, and to provide insights in advantages, limitations, and practicability of recent advances. Copyright © 2015 Elsevier Inc. All rights reserved.

Triolein-based polycation lipid nanocarrier for efficient gene delivery: characteristics and mechanism

PubMed Central

Zhang, Zhiwen; Fang, Xiaoling; Hao, Junguo; Li, Yajuan; Sha, Xianyi

2011-01-01

We proposed to develop a polycation lipid nanocarrier (PLN) with higher transfection efficiency than our previously described polycation nanostrucutred lipid nanocarrier (PNLC). PLN was composed of triolein, cetylated low-molecular-weight polyethylenimine, and dioleoyl phosphatidylethanolamine. The physicochemical properties of PLN and the PLN/DNA complexes (PDC) were characterized. The in vitro transfection was performed in human lung adenocarcinoma (SPC-A1) cells, and the intracellular mechanism was investigated as well. The measurements indicated that PLN and PDC are homogenous nanometer-sized particles with a positive charge. The transfection efficiency of PDC significantly increased with the content of triolein and was higher than that of PNLC and commercial Lipofectamine™ 2000. In particular, the transfection of PLN in the presence of 10% serum was more effective than that in its absence. With the help of specific inhibitors of chlorpromazine and filipin, the clathrin-dependent endocytosis pathway was determined to be the main contributor to the successful transfection mediated by PLN in SPC-A1 cells. The captured images verified that the fluorescent PDC was localized in the lysosomes and nuclei after endocytosis. Thus, PLN represents a novel efficient nonviral gene delivery vector. PMID:22114487

Triolein-based polycation lipid nanocarrier for efficient gene delivery: characteristics and mechanism.

PubMed

Zhang, Zhiwen; Fang, Xiaoling; Hao, Junguo; Li, Yajuan; Sha, Xianyi

2011-01-01

We proposed to develop a polycation lipid nanocarrier (PLN) with higher transfection efficiency than our previously described polycation nanostrucutred lipid nanocarrier (PNLC). PLN was composed of triolein, cetylated low-molecular-weight polyethylenimine, and dioleoyl phosphatidylethanolamine. The physicochemical properties of PLN and the PLN/DNA complexes (PDC) were characterized. The in vitro transfection was performed in human lung adenocarcinoma (SPC-A1) cells, and the intracellular mechanism was investigated as well. The measurements indicated that PLN and PDC are homogenous nanometer-sized particles with a positive charge. The transfection efficiency of PDC significantly increased with the content of triolein and was higher than that of PNLC and commercial Lipofectamine 2000. In particular, the transfection of PLN in the presence of 10% serum was more effective than that in its absence. With the help of specific inhibitors of chlorpromazine and filipin, the clathrin-dependent endocytosis pathway was determined to be the main contributor to the successful transfection mediated by PLN in SPC-A1 cells. The captured images verified that the fluorescent PDC was localized in the lysosomes and nuclei after endocytosis. Thus, PLN represents a novel efficient nonviral gene delivery vector.

Modulation of Endosomal Escape of IRQ-PEGylated Nano-carrier

NASA Astrophysics Data System (ADS)

Mudhakir, Diky; Akita, Hidetaka; Harashima, Hideyoshi

2011-12-01

The novel IRQ peptide is one of cell penetrating peptides (CPPs) that has ability to induce endosomal escape. It has been demonstrated that IRQ ligand had ability to facilitate an escape of liposomes encapsulating siRNA from the endosomes presumably by fusion-independent mechanism [1,2]. In the present study, we attempted to modulate the intracellular trafficking of IRQ-modified nano-carrier in term of escaping process by changing the lipid composition. The peptide was attached to the terminal end of maleimide group of polyethylene glycol-modified liposomes (IRQ-PEG-Lip). The liposomes were composed of DOTAP, DOPE and cholesterol and it was labeled by water soluble sulpho-rhodamine B (Sr-B). The escape of PEG-coated liposomes was then observed by confocal laser scanning microscope after the endosomes were stained with Lysosensor. The results exhibited that IRQ-PEG-Lip was escaped from endosomal compartment after 1 h transfection when 40% of DOPE was incorporated into the nanostructure comparing to that of PEG-Lip. These results are consistent with the previous results that the IRQ facilitates endosomal escape via independent-mechanism. However, IRQ-PEG-Lip were then completely co-localized in the acidic compartment when density of DOPE was reduced approximately 20%. These results indicated that the utilizing of DOPE is important for the escape process even in the presence of hydrophilic PEG polymer. In conclusion, the regulation of endosomal escape ability of the PEGylated-IRQ nano-carrier was induced by fusion-independent manner as well as fusogenic lipid.

Shaping Nanoparticles with Hydrophilic Compositions and Hydrophobic Properties as Nanocarriers for Antibiotic Delivery

PubMed Central

2015-01-01

Inspired by the lotus effect in nature, surface roughness engineering has led to novel materials and applications in many fields. Despite the rapid progress in superhydrophobic and superoleophobic materials, this concept of Mother Nature’s choice is yet to be applied in the design of advanced nanocarriers for drug delivery. Pioneering work has emerged in the development of nanoparticles with rough surfaces for gene delivery; however, the preparation of nanoparticles with hydrophilic compositions but with enhanced hydrophobic property at the nanoscale level employing surface topology engineering remains a challenge. Herein we report for the first time the unique properties of mesoporous hollow silica (MHS) nanospheres with controlled surface roughness. Compared to MHS with a smooth surface, rough mesoporous hollow silica (RMHS) nanoparticles with the same hydrophilic composition show unusual hydrophobicity, leading to higher adsorption of a range of hydrophobic molecules and controlled release of hydrophilic molecules. RMHS loaded with vancomycin exhibits an enhanced antibacterial effect. Our strategy provides a new pathway in the design of novel nanocarriers for diverse bioapplications. PMID:27162988

Detection of hemolytic Listeria monocytogenes by using DNA colony hybridization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datta, A.R.; Wentz, B.A.; Hill, W.E.

1987-09-01

A fragment of about 500 base pairs of the beta-hemolysin gene from Listeria monocytogenes was used to screen different bacterial strains by DNA colony hybridization. The cells in the colonies were lysed by microwaves in the presence of sodium hydroxide. Of 52 different strains of Listeria species screened, only the DNA from beta-hemolytic (CAMP-positive) strains of L. monocytogenes hybridized with this probe.

Assembling of multifunctional latex-based hybrid nanocarriers from Calotropis gigantea for sustained (doxorubicin) DOX releases.

PubMed

Pradeepkumar, Periyakaruppan; Govindaraj, Dharman; Jeyaraj, Murugaraj; Munusamy, Murugan A; Rajan, Mariappan

2017-03-01

Natural rubber Latex (Lax) is a colloidal dispersion of polymer particles in liquid and shows good biodegradable, biocompatibility, and non-toxicity. Natural polymers are the most important materials used in food packaging, micro/nano-drug delivery, tissue engineering, agriculture, and coating. In the present study, natural compounds extracted from plant Lax were designed to function as drug carriers using various surfactants via emulation and solvent evaporation method. Calotropis gigantea belongs to the family Apocynaceae and has received considerable attention in modern medicine, ayurvedeic, siddha, and traditional medicine. Since, we were isolated biodegradable, non-toxic, and biocompatible materials as latex from Calotropis gigantea plant. The Lax was separated as per their solubility nature and it was designed as a carrier using surfactant namely; Sorbitanmonolaurate (Span-20), sodium lauryl sulfate (SLS), and cetyltrimethylammonium bromide (CTAB). The isolated compounds from Lax of Calotropis gigantea were analyzed using high-performance liquid chromatography. To confirm the encapsulation efficiency and in vitro drug release of the carriers, doxorubicin (DOX) was used as a model natural drug. The hybrid nanocarriers were successfully synthesized through simple solvent evaporation using three surfactants, and the morphology was characterized by SEM and TEM technique. The functionality and crystalline nature of the nanocarriers were confirmed using FTIR and XRD, respectively. Within 90min, the maximum amount of DOX was encapsulated in the carriers, and prolonged cumulative drug release by the nanocarriers was observed. The formulated natural carriers were found to have potentially effective cytotoxic effects on lung cancer cells. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Polymer Nanocarriers for Dentin Adhesion

PubMed Central

Osorio, R.; Osorio, E.; Medina-Castillo, A.L.; Toledano, M.

2014-01-01

To obtain more durable adhesion to dentin, and to protect collagen fibrils of the dentin matrix from degradation, calcium- and phosphate-releasing particles have been incorporated into the dental adhesive procedure. The aim of the present study was to incorporate zinc-loaded polymeric nanocarriers into a dental adhesive system to facilitate inhibition of matrix metalloproteinases (MMPs)-mediated collagen degradation and to provide calcium ions for mineral deposition within the resin-dentin bonded interface. PolymP-nActive nanoparticles (nanoMyP) were zinc-loaded through 30-minute ZnCl2 immersion and tested for bioactivity by means of 7 days’ immersion in simulated body fluid solution (the Kokubo test). Zinc-loading and calcium phosphate depositions were examined by scanning and transmission electron microscopy, elemental analysis, and x-ray diffraction. Nanoparticles in ethanol solution infiltrated into phosphoric-acid-etched human dentin and Single Bond (3M/ESPE) were applied to determine whether the nanoparticles interfered with bonding. Debonded sticks were analyzed by scanning electron microscopy. A metalloproteinase collagen degradation assay was also performed in resin-infiltrated dentin with and without nanoparticles, measuring C-terminal telopeptide of type I collagen (ICTP) concentration in supernatants, after 4 wk of immersion in artificial saliva. Numerical data were analyzed by analysis of variance (ANOVA) and Student-Newman-Keuls multiple comparisons tests (p < .05). Nanoparticles were effectively zinc-loaded and were shown to have a chelating effect, retaining calcium regardless of zinc incorporation. Nanoparticles failed to infiltrate demineralized intertubular dentin and remained on top of the hybrid layer, without altering bond strength. Calcium and phosphorus were found covering nanoparticles at the hybrid layer, after 24 h. Nanoparticle application in etched dentin also reduced MMP-mediated collagen degradation. Tested nanoparticles may be

Fluorescent carbon dots as an efficient siRNA nanocarrier for its interference therapy in gastric cancer cells.

PubMed

Wang, Qing; Zhang, Chunlei; Shen, Guangxia; Liu, Huiyang; Fu, Hualin; Cui, Daxiang

2014-12-30

Fluorescent carbon dots (Cdots) have attracted increasing attention due to their potential applications in sensing, catalysis, and biomedicine. Currently, intensive research has been concentrated on the synthesis and imaging-guided therapy of these benign photoluminescent materials. Meanwhile, Cdots have been explored as nonviral vector for nucleic acid or drug delivery by chemical modification on purpose. We have developed a microwave assisted one-step synthesis of Cdots with citric acid as carbon source and tryptophan (Trp) as both nitrogen source and passivation agent. The Cdots with uniform size show superior water solubility, excellent biocompatibility, and high quantum yield. Afterwards, the PEI (polyethylenimine)-adsorbed Cdots nanoparticles (Cdots@PEI) were applied to deliver Survivin siRNA into human gastric cancer cell line MGC-803. The results have confirmed the nanocarrier exhibited excellent biocompatibility and a significant increase in cellular delivery of siRNA, inducing efficient knockdown for Survivin protein to 6.1%. In addition, PEI@Cdots complexes mediated Survivin silencing, the arrested cell cycle progression in G1 phase as well as cell apoptosis was observed. The Cdots-based and PEI-adsorbed complexes both as imaging agents and siRNA nanocarriers have been developed for Survivin siRNA delivery. And the results indicate that Cdots-based nanocarriers could be utilized in a broad range of siRNA delivery systems for cancer therapy.

Targeting renin-angiotensin system in malignant hypertension in atypical hemolytic uremic syndrome

PubMed Central

Raghunathan, V.; Sethi, S. K.; Dragon-Durey, M. A.; Dhaliwal, M.; Raina, R.; Jha, P.; Bansal, S. B.; Kher, V.

2017-01-01

Hypertension is common in hemolytic uremic syndrome (HUS) and often difficult to control. Local renin-angiotensin activation is believed to be an important part of thrombotic microangiopathy, leading to a vicious cycle of progressive renal injury and intractable hypertension. This has been demonstrated in vitro via enhanced tissue factor expression on glomerular endothelial cells which is enhanced by angiotensin II. We report two pediatric cases of atypical HUS with severe refractory malignant hypertension, in which we targeted the renin-angiotensin system by using intravenous (IV) enalaprilat, oral aliskiren, and oral enalapril with quick and dramatic response of blood pressure. Both drugs, aliskiren and IV enalaprilat, were effective in controlling hypertension refractory to multiple antihypertensive medications. These appear to be promising alternatives in the treatment of severe atypical HUS-induced hypertension and hypertensive emergency. PMID:28356668

Pathogenic role of inflammatory response during Shiga toxin-associated hemolytic uremic syndrome (HUS).

PubMed

Exeni, Ramon Alfonso; Fernandez-Brando, Romina Jimena; Santiago, Adriana Patricia; Fiorentino, Gabriela Alejandra; Exeni, Andrea Mariana; Ramos, Maria Victoria; Palermo, Marina Sandra

2018-01-25

Hemolytic uremic syndrome (HUS) is defined as a triad of noninmune microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. The most frequent presentation is secondary to Shiga toxin (Stx)-producing Escherichia coli (STEC) infections, which is termed postdiarrheal, epidemiologic or Stx-HUS, considering that Stx is the necessary etiological factor. After ingestion, STEC colonize the intestine and produce Stx, which translocates across the intestinal epithelium. Once Stx enters the bloodstream, it interacts with renal endothelial and epithelial cells, and leukocytes. This review summarizes the current evidence about the involvement of inflammatory components as central pathogenic factors that could determine outcome of STEC infections. Intestinal inflammation may favor epithelial leakage and subsequent passage of Stx to the systemic circulation. Vascular damage triggered by Stx promotes not only release of thrombin and increased fibrin concentration but also production of cytokines and chemokines by endothelial cells. Recent evidence from animal models and patients strongly indicate that several immune cells types may participate in HUS physiopathology: neutrophils, through release of proteases and reactive oxygen species (ROS); monocytes/macrophages through secretion of cytokines and chemokines. In addition, high levels of Bb factor and soluble C5b-9 (sC5b-9) in plasma as well as complement factors adhered to platelet-leukocyte complexes, microparticles and microvesicles, suggest activation of the alternative pathway of complement. Thus, acute immune response secondary to STEC infection, the Stx stimulatory effect on different immune cells, and inflammatory stimulus secondary to endothelial damage all together converge to define a strong inflammatory status that worsens Stx toxicity and disease.

THE GERMICIDAL AND HEMOLYTIC ACTION OF α-BROM SOAPS

PubMed Central

Eggerth, Arnold H.

1929-01-01

1. The soaps of the α-brom fatty acids are usually more germicidal than the unsubstituted soaps. Only when B. typhosus was the test organism was there no increase in germicidal action. 2. For any test organism, germicidal action of the brominated soaps increases rapidly with increasing molecular weight up to a certain point, then diminishes. This is likewise true of the hemolytic titer. The point of maximal germicidal action varies with the different species of tests organisms. In the series studied, brominated soaps of 12 and 14 carbon atoms were most germicidal for the Gram-negative organisms, while soaps of 16 and 18 carbon atoms were most germicidal for Gram-positive organisms. 3. The brominated soaps are, in general, more active in acid that in neutral or alkaline reactions. The reasons for this have been discussed in a previous paper, in which a similar phenomenon with unsubstituted soaps was observed. 4. For certain organisms, the brominated soaps are among the most rapid and potent germicides known. PMID:19869537

Sepiolite as a New Nanocarrier for DNA Transfer into Mammalian Cells: Proof of Concept, Issues and Perspectives.

PubMed

Piétrement, Olivier; Castro-Smirnov, Fidel Antonio; Le Cam, Eric; Aranda, Pilar; Ruiz-Hitzky, Eduardo; Lopez, Bernard S

2017-12-29

Sepiolite is a nanofibrous natural silicate that can be used as a nanocarrier for DNA transfer thanks to its strong interaction with DNA molecules and its ability to be naturally internalized into mammalian cells through both non-endocytic and endocytic pathways. Sepiolite, due to its ability to bind various biomolecules, could be a good candidate for use as a nanocarrier for the simultaneous vectorization of diverse biological molecules. In this paper, we review our recent work, issued from a starting collaboration with Prof. Ruiz-Hitzky, that includes diverse aspects on the characterization and main features of sepiolite/DNA nanohybrids, and we present an outlook for the further development of sepiolite for DNA transfer. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A thermolabile aldolase A mutant causes fever-induced recurrent rhabdomyolysis without hemolytic anemia.

PubMed

Mamoune, Asmaa; Bahuau, Michel; Hamel, Yamina; Serre, Valérie; Pelosi, Michele; Habarou, Florence; Nguyen Morel, Marie-Ange; Boisson, Bertrand; Vergnaud, Sabrina; Viou, Mai Thao; Nonnenmacher, Luc; Piraud, Monique; Nusbaum, Patrick; Vamecq, Joseph; Romero, Norma; Ottolenghi, Chris; Casanova, Jean-Laurent; de Lonlay, Pascale

2014-11-01

Aldolase A deficiency has been reported as a rare cause of hemolytic anemia occasionally associated with myopathy. We identified a deleterious homozygous mutation in the ALDOA gene in 3 siblings with episodic rhabdomyolysis without hemolytic anemia. Myoglobinuria was always triggered by febrile illnesses. We show that the underlying mechanism involves an exacerbation of aldolase A deficiency at high temperatures that affected myoblasts but not erythrocytes. The aldolase A deficiency was rescued by arginine supplementation in vitro but not by glycerol, betaine or benzylhydantoin, three other known chaperones, suggesting that arginine-mediated rescue operated by a mechanism other than protein chaperoning. Lipid droplets accumulated in patient myoblasts relative to control and this was increased by cytokines, and reduced by dexamethasone. Our results expand the clinical spectrum of aldolase A deficiency to isolated temperature-dependent rhabdomyolysis, and suggest that thermolability may be tissue specific. We also propose a treatment for this severe disease.

Biodistribution of biodegradable polymeric nano-carriers loaded with busulphan and designed for multimodal imaging.

PubMed

Asem, Heba; Zhao, Ying; Ye, Fei; Barrefelt, Åsa; Abedi-Valugerdi, Manuchehr; El-Sayed, Ramy; El-Serafi, Ibrahim; Abu-Salah, Khalid M; Hamm, Jörg; Muhammed, Mamoun; Hassan, Moustapha

2016-12-19

Multifunctional nanocarriers for controlled drug delivery, imaging of disease development and follow-up of treatment efficacy are promising novel tools for disease diagnosis and treatment. In the current investigation, we present a multifunctional theranostic nanocarrier system for anticancer drug delivery and molecular imaging. Superparamagnetic iron oxide nanoparticles (SPIONs) as an MRI contrast agent and busulphan as a model for lipophilic antineoplastic drugs were encapsulated into poly (ethylene glycol)-co-poly (caprolactone) (PEG-PCL) micelles via the emulsion-evaporation method, and PEG-PCL was labelled with VivoTag 680XL fluorochrome for in vivo fluorescence imaging. Busulphan entrapment efficiency was 83% while the drug release showed a sustained pattern over 10 h. SPION loaded-PEG-PCL micelles showed contrast enhancement in T 2 *-weighted MRI with high r 2 * relaxivity. In vitro cellular uptake of PEG-PCL micelles labeled with fluorescein in J774A cells was found to be time-dependent. The maximum uptake was observed after 24 h of incubation. The biodistribution of PEG-PCL micelles functionalized with VivoTag 680XL was investigated in Balb/c mice over 48 h using in vivo fluorescence imaging. The results of real-time live imaging were then confirmed by ex vivo organ imaging and histological examination. Generally, PEG-PCL micelles were highly distributed into the lungs during the first 4 h post intravenous administration, then redistributed and accumulated in liver and spleen until 48 h post administration. No pathological impairment was found in the major organs studied. Thus, with loaded contrast agent and conjugated fluorochrome, PEG-PCL micelles as biodegradable and biocompatible nanocarriers are efficient multimodal imaging agents, offering high drug loading capacity, and sustained drug release. These might offer high treatment efficacy and real-time tracking of the drug delivery system in vivo, which is crucial for designing of an efficient drug

Maternal β-hemolytic streptococcal pharyngeal exposure and colonization in pregnancy.

PubMed

Heidari-Bateni, Giv; Brar, Anoop K; Hall, Matthew; Hathcock, Trupti; Epstein, Deirdre; Goessling, Lisa S; Cunningham, Madeleine W; Eghtesady, Pirooz

2014-01-01

To report the pharyngeal colonization rate of β-hemolytic streptococci and changes in the value of antistreptolysin O (ASO) and anti-DNase B serology titers during pregnancy. Healthy pregnant women were recruited and blood was drawn in each trimester. The upper limit of normal (ULN) values for ASO and anti-DNase B was calculated for each trimester. Throat swabs were collected for culture and positive cultures were further assessed for the identification of serogroup of the isolated β-hemolytic streptococcus. Out of a total of 126 pregnant women, 34.1% had positive throat cultures. Group C and group G strains were isolated in 18.2% of throat cultures while group F was detected in 13.5% of cases. The rate of colonization with GAS was 1.6%. There was an overall drop in ASO titer during pregnancy while anti-DNase B titers remained relatively unchanged. ULN values of 164(IU), 157(IU), and 156(IU) were calculated for ASO at the first, second, and third trimesters, respectively. Based on the ULN values, 28.6% of patients had recent streptococcal exposure. These results show that pregnant women act as a reservoir for spreading potentially immunogenic (groups C and G) and disease producing (group F) virulent strains of streptococci.

Simultaneous delivery of Paclitaxel and Bcl-2 siRNA via pH-Sensitive liposomal nanocarrier for the synergistic treatment of melanoma

NASA Astrophysics Data System (ADS)

Reddy, Teegala Lakshminarayan; Garikapati, Koteswara Rao; Reddy, S. Gopal; Reddy, B. V. Subba; Yadav, J. S.; Bhadra, Utpal; Bhadra, Manika Pal

2016-10-01

pH-sensitive drug carriers that are sensitive to the acidic (pH = ~6.5) microenvironments of tumor tissues have been primarily used as effective drug/gene/siRNA/microRNA carriers for releasing their payloads to tumor cells/tissues. Resistance to various drugs has become a big hurdle in systemic chemotherapy in cancer. Therefore delivery of chemotherapeutic agents and siRNA’s targeting anti apoptotic genes possess advantages to overcome the efflux pump mediated and anti apoptosis-related drug resistance. Here, we report the development of nanocarrier system prepared from kojic acid backbone-based cationic amphiphile containing endosomal pH-sensitive imidazole ring. This pH-sensitive liposomal nanocarrier effectively delivers anti-cancer drug (Paclitaxel; PTX) and siRNA (Bcl-2), and significantly inhibits cell proliferation and reduces tumor growth. Tumor inhibition response attributes to the synergistic effect of PTX potency and MDR reversing ability of Bcl-2 siRNA in the tumor supporting that kojic acid based liposomal pH-sensitive nanocarrier as efficient vehicle for systemic co-delivery of drugs and siRNA.

Lipopolysaccharide based oral nanocarriers for the improvement of bioavailability and anticancer efficacy of curcumin.

PubMed

Chaurasia, Sundeep; Patel, Ravi R; Chaubey, Pramila; Kumar, Nagendra; Khan, Gayasuddin; Mishra, Brahmeshwar

2015-10-05

Soluthin MD(®), a unique phosphatidylcholine-maltodextrin based hydrophilic lipopolysaccharide, which exhibits superior biocompatibility and bioavailability enhancer properties for poorly water soluble drug(s). Curcumin (CUR) is a potential natural anticancer drug with low bioavailability due to poor aqueous solubility. The study aims at formulation and optimization of CUR loaded lipopolysaccharide nanocarriers (C-LPNCs) to enhance oral bioavailability and anticancer efficacy in colon-26 tumor-bearing mice in vitro and in vivo. The Optimized C-LPNCs demonstrated favorable mean particle size (108 ± 3.4 nm) and percent entrapment efficiency (65.29 ± 1.0%). Pharmacokinetic parameters revealed ∼130-fold increase in oral bioavailability and cytotoxicity studies demonstrated ∼23-fold reduction in 50% cell growth inhibition when treated with optimized C-LPNCs as compared to pure CUR. In vivo anticancer study performed with optimized C-LPNCs showed significant increase in efficacy compared with pure CUR. Thus, lipopolysaccharide nanocarriers show potential delivery strategy to improve oral bioavailability and anticancer efficacy of CUR in the treatment of colorectal cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Graphene oxide as a nanocarrier for controlled release and targeted delivery of an anticancer active agent, chlorogenic acid.

PubMed

Barahuie, Farahnaz; Saifullah, Bullo; Dorniani, Dena; Fakurazi, Sharida; Karthivashan, Govindarajan; Hussein, Mohd Zobir; Elfghi, Fawzi M

2017-05-01

We have synthesized graphene oxide using improved Hummer's method in order to explore the potential use of the resulting graphene oxide as a nanocarrier for an active anticancer agent, chlorogenic acid (CA). The synthesized graphene oxide and chlorogenic acid-graphene oxide nanocomposite (CAGO) were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential thermogravimetry analysis, Raman spectroscopy, powder X-ray diffraction (PXRD), UV-vis spectroscopy and high resolution transmission electron microscopy (HRTEM) techniques. The successful conjugation of chlorogenic acid onto graphene oxide through hydrogen bonding and π-π interaction was confirmed by Raman spectroscopy, FTIR analysis and X-ray diffraction patterns. The loading of CA in the nanohybrid was estimated to be around 13.1% by UV-vis spectroscopy. The release profiles showed favourable, sustained and pH-dependent release of CA from CAGO nanocomposite and conformed well to the pseudo-second order kinetic model. Furthermore, the designed anticancer nanohybrid was thermally more stable than its counterpart. The in vitro cytotoxicity results revealed insignificant toxicity effect towards normal cell line, with a viability of >80% even at higher concentration of 50μg/mL. Contrarily, CAGO nanocomposite revealed enhanced toxic effect towards evaluated cancer cell lines (HepG2 human liver hepatocellular carcinoma cell line, A549 human lung adenocarcinoma epithelial cell line, and HeLa human cervical cancer cell line) compared to its free form. Copyright © 2016 Elsevier B.V. All rights reserved.

An infant with acute brucellosis presenting with Coombs-positive autoimmune hemolytic anemia: is breastfeeding guilty for transmission?

PubMed

Apa, Hurşit; Keskin, Sükran; Gülfidan, Gamze; Yaman, Yöntem; Devrim, Ilker

2013-07-01

Brucellosis is a zoonotic infectious disease that can be transmitted to humans through infected milk and dairy products. There are limited cases with Brucella infection acquired via breastfeeding in infants in the literature. Also, Coombs-positive autoimmune hemolytic anemia as a result of the disease is comparatively rare when considering the other frequent hematologic complications. We report a mother who acquired the infection as a result of consuming infected milk and dairy products after delivery and of her 5-month-old baby, who had acquired the disease via breastfeeding and presented with Coombs-positive autoimmune hemolytic anemia.

Ultra-performance liquid chromatography-tandem mass spectrometry-based multiplex enzyme assay for six enzymes associated with hereditary hemolytic anemia.

PubMed

Park, Chul Min; Lee, Kyunghoon; Jun, Sun-Hee; Song, Sang Hoon; Song, Junghan

2017-08-15

Deficiencies in erythrocyte metabolic enzymes are associated with hereditary hemolytic anemia. Here, we report the development of a novel multiplex enzyme assay for six major enzymes, namely glucose-6-phosphate dehydrogenase, pyruvate kinase, pyrimidine 5'-nucleotidase, hexokinase, triosephosphate isomerase, and adenosine deaminase, deficiencies in which are implicated in erythrocyte enzymopathies. To overcome the drawbacks of traditional spectrophotometric enzyme assays, the present assay was based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The products of the six enzymes were directly measured by using ion pairing UPLC-MS/MS, and the precision, linearity, ion suppression, optimal sample amounts, and incubation times were evaluated. Eighty-three normal individuals and 13 patients with suspected enzymopathy were analyzed. The UPLC running time was within 5min. No ion suppression was observed at the retention time for the products or internal standards. We selected an optimal dilution factor and incubation time for each enzyme system. The intra- and inter-assay imprecision values (CVs) were 2.5-12.1% and 2.9-14.3%, respectively. The linearity of each system was good, with R 2 values >0.97. Patient samples showed consistently lower enzyme activities than those from normal individuals. The present ion paring UPLC-MS/MS assay enables facile and reproducible multiplex evaluation of the activity of enzymes implicated in enzymopathy-associated hemolytic anemia. Copyright © 2017 Elsevier B.V. All rights reserved.

Zein-based Nanocarriers as Potential Natural Alternatives for Drug and Gene Delivery: Focus on Cancer Therapy.

PubMed

Elzoghby, Ahmed; Freag, May; Mamdouh, Hadeer; Elkhodairy, Kadria

2017-01-01

Protein nanocarriers possess unique merits including minimal cytotoxicity, numerous renewable sources, and high drug-binding capability. In opposition to delivery carriers utilizing hydrophilic animal proteins, hydrophobic plant proteins (e.g, zein) have great tendency in fabricating controlled-release particulate carriers without additional chemical modification to stiffen them, which in turn evades the use of toxic chemical crosslinkers. Moreover, zein is related to a class of alcohol-soluble prolamins and generally recognized as safe (GRAS) carrier for drug delivery. Various techniques have been adopted to fabricate zein-based nanoparticulate systems including phase separation coacervation, spray-drying, supercritical anti-solvent approach, electrospinning and self-assembly. This manuscript reviews the recent advances in the zein-based colloidal nano-carrier systems such as nanospheres, nanocapsules, micelles and nanofibers with a special focus on their physicochemical characteristics and drug delivery applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Irinotecan-encapsulated double-reverse thermosensitive nanocarrier system for rectal administration.

PubMed

Din, Fakhar Ud; Choi, Ju Yeon; Kim, Dong Wuk; Mustapha, Omer; Kim, Dong Shik; Thapa, Raj Kumar; Ku, Sae Kwang; Youn, Yu Seok; Oh, Kyung Taek; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

2017-11-01

Intravenously administered for the treatment of rectum cancer, irinotecan produces severe side effects due to very high plasma concentrations. A novel irinotecan-encapsulated double reverse thermosensitive nanocarrier system (DRTN) for rectal administration was developed as an alternative. The DRTN was fabricated by dispersing the thermosensitive irinotecan-encapsulated solid lipid nanoparticles (SLN) in the thermosensitive poloxamer solution. Its gel properties, pharmacokinetics, morphology, anticancer activity and immunohistopathology were assessed after its rectal administration to rats and tumor-bearing mice. In the DRTN, the solid form of the SLN and the liquid form of the poloxamer solution persisted at 25 °C; the former melted to liquid, and the latter altered to gel at 36.5 °C. The DRTN was easily administered to the anus, gelling rapidly and strongly after rectal administration. Compared to the conventional hydrogel and intravenously administered solution, it retarded dissolution and initial plasma concentration. The DRTN gave sustained release and nearly constant plasma concentrations of irinotecan at 1-3 h in rats, resulting in improved anticancer activity. It induced no damage to the rat rectum and no body weight loss in tumor-bearing mice. Thus, this irinotecan-encapsulated DRTN associated with a reduced burst effect, lack of toxicity and excellent antitumor efficacy would be strongly recommended as a rectal pharmaceutical product alternative to commercial intravenous injection in the treatment of rectum and colon cancer.

[Microalbuminuria in pediatric patients diagnosed with hemolytic uremic syndrome].

PubMed

Cubillos C, María Paz; Del Salas, Paulina; Zambrano, Pedro O

2015-01-01

Hemolytic uremic syndrome (HUS) is characterized by the presence of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney failure. It is the leading cause of acute kidney failure in children under 3 years of age. A variable number of patients develop proteinuria, hypertension, and chronic renal failure. To evaluate the renal involvement in pediatric patients diagnosed with HUS using the microalbumin/creatinine ratio. Descriptive concurrent cohort study that analyzed the presence of microalbuminuria in patients diagnosed with HUS between January 2001 and March 2012, who evolved without hypertension and normal renal function (clearance greater than 90ml/min using Schwartz formula). Demographic factors (age, sex), clinical presentation at time of diagnosis, use of antibiotics prior to admission, and need for renal replacement therapy were evaluated. Of the 24 patients studied, 54% were male. The mean age at diagnosis was two years. Peritoneal dialysis was required in 45%, and 33% developed persistent microalbuminuria. Antiproteinuric treatment was introduce in 4 patients, with good response. The mean follow-up was 6 years (range 6 months to 11 years). The serum creatinine returned to normal in all patients during follow up. The percentage of persistent microalbuminuria found in patients with a previous diagnosis of HUS was similar in our group to that described in the literature. Antiproteinuric treatment could delay kidney damage, but further multicenter prospective studies are necessary. Copyright © 2015. Publicado por Elsevier España, S.L.U.

Effects of extremely low frequency magnetic field on production of mannatide by α-hemolytic Streptococcus.

PubMed

Zhang, Jialan; Xu, Cui; Wan, Yunlei; Gao, Mengxiang

2016-07-01

The effect of the extremely low frequency magnetic field (ELF-MF) on biomass and mannatide production by α-hemolytic Streptococcus in liquid-state fermentation culture medium was studied during shake flask culture. Magnetic field (MF) inductions, exposure times, and exposure periods varied in a range of 0-1.5 mT, 0-16 h, and six periods of incubation time, respectively. Results showed both biomass and mannatide production increased significantly at MF induction 0.4, 0.6, and 0.9 mT and decreased at both 1.2 and 1.5 mT. Biomass increased by exposure for initial and middle stages of fermentation. Mannatide production increased significantly at 4-8, 8-12, and 17-21 h. Peak yield of biomass and mannatide production increased by 10.7% and 14.0% at 25 and 27 h of incubation at 0.6 mT MF induction and exposure to 8-12 h of incubation time, compared with the control experiment, respectively. ELF-MF could also enhance the growth rate and mannatide production rate of α-hemolytic Streptococcus. However, ELF-MF did not alter α-hemolytic Streptococcus cell growth and mannatide metabolizing regulation or fermentation pattern. Mannatide production was not associated with cellular growth but rather only partially associated. Bioelectromagnetics. 37:331-337, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Blueberry muffin rash, hyperbilirubinemia, and hypoglycemia: a case of hemolytic disease of the fetus and newborn due to anti-Kp(a).

PubMed

Brumbaugh, J E; Morgan, S; Beck, J C; Zantek, N; Kearney, S; Bendel, C M; Roberts, K D

2011-05-01

Hemolytic disease of the fetus and newborn occurs when maternal IgG antibodies cross the placenta and cause hemolysis of fetal red blood cells. Kp(a) is a low frequency red blood cell antigen that has rarely been implicated in hemolytic disease of the fetus and newborn. The few reported cases attributed to anti-Kp(a) have typically had minimal clinical consequences. We report a critically ill neonate who presented with purpura, respiratory failure, severe liver dysfunction, hyperbilirubinemia, hypoglycemia and anemia. This case report broadens the spectrum of neonatal disease associated with anti-Kp(a), addresses the evaluation of hemolysis with liver failure in a neonate, and emphasizes the importance of screening for antibodies to low frequency red blood cell antigens in suspected hemolytic disease of the fetus and newborn.

78 FR 79469 - Strategies To Address Hemolytic Complications of Immune Globulin Infusions; Public Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-30

...] Strategies To Address Hemolytic Complications of Immune Globulin Infusions; Public Workshop AGENCY: Food and... Infusions.'' The purpose of the public workshop is to identify and discuss potential risk mitigation...) (Human) infusion. Complications of hemolysis include severe anemia requiring transfusion, renal failure...

Vascular Targeting of Nanocarriers: Perplexing Aspects of the Seemingly Straightforward Paradigm

PubMed Central

2015-01-01

Targeted nanomedicine holds promise to find clinical use in many medical areas. Endothelial cells that line the luminal surface of blood vessels represent a key target for treatment of inflammation, ischemia, thrombosis, stroke, and other neurological, cardiovascular, pulmonary, and oncological conditions. In other cases, the endothelium is a barrier for tissue penetration or a victim of adverse effects. Several endothelial surface markers including peptidases (e.g., ACE, APP, and APN) and adhesion molecules (e.g., ICAM-1 and PECAM) have been identified as key targets. Binding of nanocarriers to these molecules enables drug targeting and subsequent penetration into or across the endothelium, offering therapeutic effects that are unattainable by their nontargeted counterparts. We analyze diverse aspects of endothelial nanomedicine including (i) circulation and targeting of carriers with diverse geometries, (ii) multivalent interactions of carrier with endothelium, (iii) anchoring to multiple determinants, (iv) accessibility of binding sites and cellular response to their engagement, (v) role of cell phenotype and microenvironment in targeting, (vi) optimization of targeting by lowering carrier avidity, (vii) endocytosis of multivalent carriers via molecules not implicated in internalization of their ligands, and (viii) modulation of cellular uptake and trafficking by selection of specific epitopes on the target determinant, carrier geometry, and hydrodynamic factors. Refinement of these aspects and improving our understanding of vascular biology and pathology is likely to enable the clinical translation of vascular endothelial targeting of nanocarriers. PMID:24787360

Chitosan-coated mesoporous MIL-100(Fe) nanoparticles as improved bio-compatible oral nanocarriers

PubMed Central

Hidalgo, T.; Giménez-Marqués, M.; Bellido, E.; Avila, J.; Asensio, M. C.; Salles, F.; Lozano, M. V.; Guillevic, M.; Simón-Vázquez, R.; González-Fernández, A.; Serre, C.; Alonso, M. J.; Horcajada, P.

2017-01-01

Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related to pain and severe complications; whereas nanoMOFs for oral administration, a commonly used non-invasive and simpler route, remains however unexplored. We propose here the biofriendly preparation of a suitable oral nanocarrier based on the benchmarked biocompatible mesoporous iron(III) trimesate nanoparticles coated with the bioadhesive polysaccharide chitosan (CS). This method does not hamper the textural/structural properties and the sorption/release abilities of the nanoMOFs upon surface engineering. The interaction between the CS and the nanoparticles has been characterized through a combination of high resolution soft X-ray absorption and computing simulation, while the positive impact of the coating on the colloidal and chemical stability under oral simulated conditions is here demonstrated. Finally, the intestinal barrier bypass capability and biocompatibility of CS-coated nanoMOF have been assessed in vitro, leading to an increased intestinal permeability with respect to the non-coated material, maintaining an optimal biocompatibility. In conclusion, the preservation of the interesting physicochemical features of the CS-coated nanoMOF and their adapted colloidal stability and progressive biodegradation, together with their improved intestinal barrier bypass, make these nanoparticles a promising oral nanocarrier. PMID:28256600

Chitosan-coated mesoporous MIL-100(Fe) nanoparticles as improved bio-compatible oral nanocarriers

NASA Astrophysics Data System (ADS)

Hidalgo, T.; Giménez-Marqués, M.; Bellido, E.; Avila, J.; Asensio, M. C.; Salles, F.; Lozano, M. V.; Guillevic, M.; Simón-Vázquez, R.; González-Fernández, A.; Serre, C.; Alonso, M. J.; Horcajada, P.

2017-03-01

Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related to pain and severe complications; whereas nanoMOFs for oral administration, a commonly used non-invasive and simpler route, remains however unexplored. We propose here the biofriendly preparation of a suitable oral nanocarrier based on the benchmarked biocompatible mesoporous iron(III) trimesate nanoparticles coated with the bioadhesive polysaccharide chitosan (CS). This method does not hamper the textural/structural properties and the sorption/release abilities of the nanoMOFs upon surface engineering. The interaction between the CS and the nanoparticles has been characterized through a combination of high resolution soft X-ray absorption and computing simulation, while the positive impact of the coating on the colloidal and chemical stability under oral simulated conditions is here demonstrated. Finally, the intestinal barrier bypass capability and biocompatibility of CS-coated nanoMOF have been assessed in vitro, leading to an increased intestinal permeability with respect to the non-coated material, maintaining an optimal biocompatibility. In conclusion, the preservation of the interesting physicochemical features of the CS-coated nanoMOF and their adapted colloidal stability and progressive biodegradation, together with their improved intestinal barrier bypass, make these nanoparticles a promising oral nanocarrier.

Mechanisms of Action of (Meth)acrylates in Hemolytic Activity, in Vivo Toxicity and Dipalmitoylphosphatidylcholine (DPPC) Liposomes Determined Using NMR Spectroscopy

PubMed Central

Fujisawa, Seiichiro; Kadoma, Yoshinori

2012-01-01

We investigated the quantitative structure-activity relationships between hemolytic activity (log 1/H50) or in vivo mouse intraperitoneal (ip) LD50 using reported data for α,β-unsaturated carbonyl compounds such as (meth)acrylate monomers and their 13C-NMR β-carbon chemical shift (δ). The log 1/H50 value for methacrylates was linearly correlated with the δCβ value. That for (meth)acrylates was linearly correlated with log P, an index of lipophilicity. The ipLD50 for (meth)acrylates was linearly correlated with δCβ but not with log P. For (meth)acrylates, the δCβ value, which is dependent on the π-electron density on the β-carbon, was linearly correlated with PM3-based theoretical parameters (chemical hardness, η; electronegativity, χ; electrophilicity, ω), whereas log P was linearly correlated with heat of formation (HF). Also, the interaction between (meth)acrylates and DPPC liposomes in cell membrane molecular models was investigated using 1H-NMR spectroscopy and differential scanning calorimetry (DSC). The log 1/H50 value was related to the difference in chemical shift (ΔδHa) (Ha: H (trans) attached to the β-carbon) between the free monomer and the DPPC liposome-bound monomer. Monomer-induced DSC phase transition properties were related to HF for monomers. NMR chemical shifts may represent a valuable parameter for investigating the biological mechanisms of action of (meth)acrylates. PMID:22312284

Mechanisms of action of (meth)acrylates in hemolytic activity, in vivo toxicity and dipalmitoylphosphatidylcholine (DPPC) liposomes determined using NMR spectroscopy.

PubMed

Fujisawa, Seiichiro; Kadoma, Yoshinori

2012-01-01

We investigated the quantitative structure-activity relationships between hemolytic activity (log 1/H(50)) or in vivo mouse intraperitoneal (ip) LD(50) using reported data for α,β-unsaturated carbonyl compounds such as (meth)acrylate monomers and their (13)C-NMR β-carbon chemical shift (δ). The log 1/H(50) value for methacrylates was linearly correlated with the δC(β) value. That for (meth)acrylates was linearly correlated with log P, an index of lipophilicity. The ipLD(50) for (meth)acrylates was linearly correlated with δC(β) but not with log P. For (meth)acrylates, the δC(β) value, which is dependent on the π-electron density on the β-carbon, was linearly correlated with PM3-based theoretical parameters (chemical hardness, η; electronegativity, χ; electrophilicity, ω), whereas log P was linearly correlated with heat of formation (HF). Also, the interaction between (meth)acrylates and DPPC liposomes in cell membrane molecular models was investigated using (1)H-NMR spectroscopy and differential scanning calorimetry (DSC). The log 1/H(50) value was related to the difference in chemical shift (ΔδHa) (Ha: H (trans) attached to the β-carbon) between the free monomer and the DPPC liposome-bound monomer. Monomer-induced DSC phase transition properties were related to HF for monomers. NMR chemical shifts may represent a valuable parameter for investigating the biological mechanisms of action of (meth)acrylates.

Lecithin-gold hybrid nanocarriers as efficient and pH selective vehicles for oral delivery of diacerein-In-vitro and in-vivo study.

PubMed

Javed, Ibrahim; Hussain, Syed Zajif; Shahzad, Atif; Khan, Jahanzeb Muhammad; Ur-Rehman, Habib; Rehman, Mubashar; Usman, Faisal; Razi, Muhammad Tahir; Shah, Muhammad Raza; Hussain, Irshad

2016-05-01

We report the synthesis and evaluation of lecithin-gold hybrid nanocarriers for the oral delivery of drugs with improved pharmacokinetics, Au-drug interactive bioactivity and controlled drug releasing behavior at physiological pH inside human body. For this purpose, diacerein, a hydrophobic anti-arthritic drug, was loaded in lecithin NPs (LD NPs), which were further coated by Au NPs either by in-situ production of Au NPs on LD NPs or by employing pre-synthesized Au NPs. All LDAu NPs were found to release drug selectively at the physiological pH of 7.4 and showed 2.5 times increase in the oral bioavailability of diacerein. Pharmacological efficacy was significantly improved i.e., greater than the additive effect of diacerein and Au NPs alone. LDAu NPs started suppressing inflammation at first phase, whereas LD NPs showed activity in the second phase of inflammation. These results indicate the interaction of Au NPs with prostaglandins and histaminic mediators of first phase of carrageenan induced inflammation. Acute toxicity study showed no hepatic damage but the renal toxicity parameters were close to the upper safety limits. Toxicity parameters were dependent on surface engineering of LDAu NPs. Apart from enhancing the oral bioavailability of hydrophobic drugs and improving their anti-inflammatory activity, these hybrid nanocarriers may have potential applications in gold-based photothermal therapy and the tracing of inflammation at atherosclerotic and arthritic site. Copyright © 2016 Elsevier B.V. All rights reserved.

pH-Responsive mineralized nanoparticles as stable nanocarriers for intracellular nitric oxide delivery.

PubMed

Lee, Hong Jae; Kim, Da Eun; Park, Dong Jin; Choi, Gi Hyun; Yang, Dal-Nim; Heo, Jung Sun; Lee, Sang Cheon

2016-10-01

We describe a calcium carbonate (CaCO3) mineralization approach to generate pH-responsive nanocarriers that can stably load S-nitrosoglutathione (GSNO) and dissolve at acidic endosomes to trigger intracellular release of nitric oxide (NO). GSNO-loaded CaCO3-mineralized nanoparticles (GSNO-MNPs) were prepared by an anionic block copolymer (PEG-Poly(l-aspartic acid))-templated mineralization. Ionic GSNO could be loaded in situ inside the CaCO3 core during the mineralization process. The stability of GSNO shielded within the crystalline CaCO3 core was greatly enhanced. The GSNO-MNPs triggered NO release at endosomal pH and an intracellular ascorbic acid level. Confocal microscopy demonstrated that the GSNO-MNPs could be dissolved at endosomal environments to release GSNO and sequentially generate NO through the GSNO reduction in the cytosol. In vitro cell experiments demonstrated that NO release by the GSNO-MNPs efficiently improved therapeutic activity of doxorubicin (DOX). Copyright © 2016 Elsevier B.V. All rights reserved.

Genome Sequence of the Hemolytic-Uremic Syndrome-Causing Strain Escherichia coli NCCP15647

PubMed Central

Jeong, Haeyoung; Zhao, Fumei; Igori, Davaajargal; Oh, Kyung-Hwan; Kim, Seon-Young; Kang, Sung Gyun; Kim, Byung Kwon; Kwon, Soon-Kyeong; Lee, Choong Hoon; Song, Ju Yeon; Yu, Dong Su; Park, Mi-Sun

2012-01-01

Enterohemorrhagic Escherichia coli (EHEC) causes a disease involving diarrhea, hemorrhagic colitis, and hemolytic-uremic syndrome (HUS). Here we present the draft genome sequence of NCCP15647, an EHEC isolate from an HUS patient. Its genome exhibits features of EHEC, such as genes for verotoxins, a type III secretion system, and prophages. PMID:22740672

Nanocarriers for delivery of platinum anticancer drugs☆

PubMed Central

Oberoi, Hardeep S.; Nukolova, Natalia V.; Kabanov, Alexander V.; Bronich, Tatiana K.

2014-01-01

Platinum based anticancer drugs have revolutionized cancer chemotherapy, and continue to be in widespread clinical use especially for management of tumors of the ovary, testes, and the head and neck. However, several dose limiting toxicities associated with platinum drug use, partial anti-tumor response in most patients, development of drug resistance, tumor relapse, and many other challenges have severely limited the patient quality of life. These limitations have motivated an extensive research effort towards development of new strategies for improving platinum therapy. Nanocarrier-based delivery of platinum compounds is one such area of intense research effort beginning to provide encouraging preclinical and clinical results and may allow the development of the next generation of platinum chemotherapy. This review highlights current understanding on the pharmacology and limitations of platinum compounds in clinical use, and provides a comprehensive analysis of various platinum–polymer complexes, micelles, dendrimers, liposomes and other nanoparticles currently under investigation for delivery of platinum drugs. PMID:24113520

[Atypical hemolytic and uremic syndrome associated with von Willebrand factor-cleaving protease (ADAMTS 13) deficiency in children].

PubMed

Ben Abdallah Chabchoub, R; Boukedi, A; Bensalah, M; Maalej, B; Gargour, L; Turk, F; Ben Halima, N; Wolf, M; Veyradier, A; Mahfoudh, A

2013-08-01

Hemolytic and uremic syndrome (HUS) is a classical form of thrombotic microangiopathies characterized by the association of hemolytic anemia with schizocytes, thrombocytopenia, and acute renal failure. Two forms of HUS have been described: the typical form that occurs after ingestion of a strain of bacteria, usually Escherichia coli types, which expresses verotoxin (also called shiga-like toxin), typically followed by bloody diarrhea, and atypical HUS, which is rare during childhood and can also be revealed by bloody diarrhea. We report a case of a 25-month-old infant who presented with hematuria and pallor after an episode of diarrhea. Biological tests revealed anemia, thrombocytopenia, and renal failure. The diagnosis of typical HUS was made, but the causal microorganism was not identified. Progression was favorable within 5 days of plasma transfusions. Two months later, the patient presented with the same symptoms and neurological impairment without any diarrhea. Von Willebrand factor-cleaving protease activity (ADAMTS 13) was low. Therefore, the diagnosis of atypical HUS by severe deficiency of ADAMTS 13 was suggested. The treatment was based on plasma transfusions resulting in remission. Atypical HUS associated with severe ADAMTS 13 deficiency rarely occurs in childhood. The prognosis, usually threatening, has been completely transformed thanks to a better understanding of the pathogenesis and to therapeutic progress. Copyright © 2013. Published by Elsevier SAS.

Polyamidoamine nanoparticles as nanocarriers for the drug delivery to malaria parasite stages in the mosquito vector.

PubMed

Urbán, Patricia; Ranucci, Elisabetta; Fernàndez-Busquets, Xavier

2015-11-01

Malaria is arguably one of the main medical concerns worldwide because of the numbers of people affected, the severity of the disease and the complexity of the life cycle of its causative agent, the protist Plasmodium spp. With the advent of nanoscience, renewed hopes have appeared of finally obtaining the long sought-after magic bullet against malaria in the form of a nanovector for the targeted delivery of antimalarial compounds exclusively to Plasmodium-infected cells, thus increasing drug efficacy and minimizing the induction of resistance to newly developed therapeutic agents. Polyamidoamine-derived nanovectors combine into a single chemical structure drug encapsulating capacity, antimalarial activity, low unspecific toxicity, specific targeting to Plasmodium, optimal in vivo activity and affordable synthesis cost. After having shown their efficacy in targeting drugs to intraerythrocytic parasites, now polyamidoamines face the challenge of spearheading a new generation of nanocarriers aiming at the malaria parasite stages in the mosquito vector.

Parvovirus B19-triggered Acute Hemolytic Anemia and Thrombocytopenia in a Child with Evans Syndrome.

PubMed

Zikidou, Panagiota; Grapsa, Anastassia; Bezirgiannidou, Zoe; Chatzimichael, Athanassios; Mantadakis, Elpis

2018-01-01

Human parvovirus B19 (HPV-B19) is the etiologic agent of erythema infectiosum, of transient aplastic crises in individuals with underlying chronic hemolytic disorders, and of chronic pure red cell aplasia in immunocompromised individuals. We describe a 14-year-old girl with long-standing Evans syndrome, who presented with severe anemia, reticulocytopenia and thrombocytopenia. A bone marrow aspirate revealed severe erythroid hypoplasia along with the presence of giant pronormoblasts, while serological studies and real-time PCR of whole blood were positive for acute parvovirus B19 infection. The patient was initially managed with corticosteroids, but both cytopenias resolved only after administration of intravenous gamma globulin 0.8g/kg. Acute parvovirus B19 infection should be suspected in patients with immunologic diseases, who present reticulocytopenic hemolytic anemia and thrombocytopenia. In this setting, intravenous gamma globulin is effective for both cytopenias.

Intravascular hemolysis induced by the venom of the Eastern coral snake, Micrurus fulvius, in a mouse model: identification of directly hemolytic phospholipases A2.

PubMed

Arce-Bejarano, Ruth; Lomonte, Bruno; Gutiérrez, José María

2014-11-01

Intravascular hemolysis has been described in envenomings by the Eastern coral snake, Micrurus fulvius, in dogs. An experimental model of intravascular hemolysis was developed in mice after intravenous (i.v.) injection of M. fulvius venom. Within one hr, there was prominent hemolysis, associated with a drastic drop in hematocrit, morphological alterations of erythrocytes, hemoglobinemia, and hemoglobinuria. Hemoglobin was identified in urine by mass spectrometry. Histological sections of kidney revealed abundant hyaline casts, probably corresponding to hemoglobin. This effect was abrogated by p-bromophenacyl bromide, indicating that it is caused by phospholipases A2 (PLA2). A monospecific anti-Micrurus nigrocinctus antivenom neutralized hemolytic activity in vivo. When tested in vitro with erythrocytes of various species, a clear difference in susceptibility was observed. Mouse and dog erythrocytes showed the highest susceptibility, whereas human and rabbit erythrocytes were not affected at the experimental conditions tested. The higher susceptibility of dog and mouse erythrocytes correlates with a high ratio of phosphatidylcholine/sphingomyelin in erythrocyte plasma membrane. When mouse erythrocytes were subjected to mechanical stress, after incubation with venom, hemolysis increased significantly, suggesting that both phospholipid hydrolysis by PLA2s and mechanical stress associated with rheological factors are likely to contribute to cell lysis in vivo. Several PLA2s isolated from this venom reproduced the hemolytic effect, and the complete amino acid sequence of one of them (fraction 17), which also induces myotoxicity, is reported. Since very few PLA2s inducing intravascular hemolysis have been described from snake venoms, this enzyme is a valuable tool to identify the structural determinants of hemolytic activity. The mouse model described in this study may be useful to explore the pathophysiology of intravascular hemolysis. Copyright © 2014 Elsevier Ltd

Spherical and tubule nanocarriers for sustained drug release

PubMed Central

Shutava, T.; Fakhrullin, R.; Lvov, Y.

2014-01-01

We discuss new trends in Layer-by-Layer (LbL) encapsulation of spherical and tubular cores of 50–150 nm diameter and loaded with drugs. This core size decrease (from few micrometers to a hundred of nanometers) for LbL encapsulation required development of sonication assistant non-washing technique and shell PEGylation to reach high colloidal stability of drug nanocarriers at 2–3 mg/mL concentration in isotonic buffers and serum. For 120–170 nm spherical LbL nanocapsules of low soluble anticancer drugs, polyelectrolyte shell thickness controls drug dissolution. As for nanotube carriers, we concentrated on natural halloysite clay nanotubes as cores for LbL encapsulation that allows high drug loading and sustains its release over tens and hundreds hours. Further drug release prolongation was reached with formation of the tube-end stoppers. PMID:25450068

Lipid nanocarriers (GeluPearl) containing amphiphilic lipid Gelucire 50/13 as a novel stabilizer: fabrication, characterization and evaluation for oral drug delivery.

PubMed

Date, Abhijit A; Vador, Nimish; Jagtap, Aarti; Nagarsenker, Mangal S

2011-07-08

To evaluate the ability of Gelucire 50/13 (an amphiphilic lipid excipient) to act as a stabilizer for lipid nanocarriers such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) and to establish the ability of Gelucire 50/13 based lipid nanocarriers to improve oral delivery of hydrophobic drugs using repaglinide (RPG) as a model drug. The ability of Gelucire 50/13 to nanosize various solid lipids was evaluated. The ability of Gelucire 50/13 to yield NLC was evaluated by using Precirol ATO 5 as a model solid lipid and various liquid lipids (oils). Gelucire 50/13 based NLC (GeluPearl) were evaluated for their ability to improve the efficacy of RPG on oral administration in comparison to RPG tablets. The short term stability of RPG-GeluPearl was evaluated at 25 °C/60% RH. Gelucire 50/13 could successfully yield SLN and NLC of various solid lipids, demonstrating its potential to act as a novel stabilizer. DSC studies indicated that Gelucire 50/13 interacts with Precirol ATO 5 and this interaction suppresses polymorphic transitions of both the components. RPG-GeluPearl exhibited significantly higher anti-diabetic activity compared to marketed RPG tablets. RPG-GeluPearl demonstrated good colloidal and chemical stability at the end of 1 month.

IgG red blood cell autoantibodies in autoimmune hemolytic anemia bind to epitopes on red blood cell membrane band 3 glycoprotein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Victoria, E.J.; Pierce, S.W.; Branks, M.J.

1990-01-01

Red blood cell (RBC) autoantibodies from patients with IgG warm-type autoimmune hemolytic anemia were labeled with iodine 125 and their RBC binding behavior characterized. Epitope-bearing RBC membrane polypeptides were identified after autoantibody immunoprecipitation of labeled membranes and immunoblotting. Immunoaffinity isolation of labeled membrane proteins with 12 different IgG hemolytic autoantibodies with protein A-agarose revealed a major polypeptide at Mr 95 to 110 kd, which coelectrophoresed on sodium dodecylsulfate-polyacrylamide gel electrophoresis with a membrane component isolated with sheep IgG anti-band 3. Immunoprecipitation studies with chymotrypsinized RBCs resulted in the recovery of two labeled membrane polypeptides with molecular weights characteristically resulting frommore » the chymotryptic fragmentation of band 3. Immunoblotting with sheep IgG anti-band 3 of the immunoprecipitated polypeptides confirmed that hemolytic autoantibody binding led to recovery of band 3 or its fragments. Two 125I-labeled IgG hemolytic autoantibodies showed binding behavior consistent with epitope localization on band 3. The labeled RBC autoantibodies bound immunospecifically to all types of human RBC tested, including those of rare Rh type (Rh-null, D--) at a site density of approximately 10(6) per RBC. The 125I-IgG in two labeled autoantibodies was 84% and 92% adsorbable by human and higher nonhuman primate RBCs. Antigen-negative animal RBC bound less than 10%, consistent with immunospecific RBC binding. IgG-1 was the major subclass in five autoantibodies tested; one of six fixed complement; and autoantibody IgG appeared polyclonal by isoelectric focusing. We conclude that IgG eluted from RBCs of patients with autoimmune hemolytic anemia consists predominantly of a single totally RBC-adsorbable antibody population that binds to antigenic determinants on band 3.« less

Rational design of gold nanocarrier for the delivery of JAG-1 peptide.

PubMed

Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Iancu, Cornel; Mocan, Lucian-Constantin

2015-06-16

Unique properties exhibited by nanoparticles makes them great candidates for applications in physics, chemistry, biology, material science and medicine. The biological applications of water-soluble gold nanoparticles range from contrast agents, delivery vehicles to therapeutics. Notch signaling is a complex network that orchestrates cell fate decisions, which involves proliferation, migration, differentiation and cell death in organisms ranging from insects to humans. Studies have showed that a correct orientation of the Jag-1 signalling protein on the substrates proves to be of great importance when promoting Jagged-1 Notch interactions, also the availability of the ligands, super cedes the importance of their concentration. The aim of the present study was to synthetize a Jag-1 functionalized nanocarrier, which would promote an efficient interaction between the Jag-1 peptide and the Notch receptor. To this end, two routes for gold nanoparticle-peptide assembly were investigated, and the synthetized bio-nanostructures were characterized and compared by means of UV-Vis, FT-IR, DLS and AFM techniques. We have obtained a stable, monodisperse, hetero-functionalized GNP-PEG-JAG-1 bio-nanostructure for Notch pathway activation applications.

Nanocarriers for optimizing the balance between interfollicular permeation and follicular uptake of topically applied clobetasol to minimize adverse effects.

PubMed

Mathes, C; Melero, A; Conrad, P; Vogt, T; Rigo, L; Selzer, D; Prado, W A; De Rossi, C; Garrigues, T M; Hansen, S; Guterres, S S; Pohlmann, A R; Beck, R C R; Lehr, C-M; Schaefer, U F

2016-02-10

The treatment of various hair disorders has become a central focus of good dermatologic patient care as it affects men and women all over the world. For many inflammatory-based scalp diseases, glucocorticoids are an essential part of treatment, even though they are known to cause systemic as well as local adverse effects when applied topically. Therefore, efficient targeting and avoidance of these side effects are of utmost importance. Optimizing the balance between drug release, interfollicular permeation, and follicular uptake may allow minimizing these adverse events and simultaneously improve drug delivery, given that one succeeds in targeting a sustained release formulation to the hair follicle. To test this hypothesis, three types of polymeric nanocarriers (nanospheres, nanocapsules, lipid-core nanocapsules) for the potent glucocorticoid clobetasol propionate (CP) were prepared. They all exhibited a sustained release of drug, as was desired. The particles were formulated as a dispersion and hydrogel and (partially) labeled with Rhodamin B for quantification purposes. Follicular uptake was investigated using the Differential Stripping method and was found highest for nanocapsules in dispersion after application of massage. Moreover, the active ingredient (CP) as well as the nanocarrier (Rhodamin B labeled polymer) recovered in the hair follicle were measured simultaneously, revealing an equivalent uptake of both. In contrast, only negligible amounts of CP could be detected in the hair follicle when applied as free drug in solution or hydrogel, regardless of any massage. Skin permeation experiments using heat-separated human epidermis mounted in Franz Diffusion cells revealed equivalent reduced transdermal permeability for all nanocarriers in comparison to application of the free drug. Combining these results, nanocapsules formulated as an aqueous dispersion and applied by massage appeare to be a good candidate to maximize follicular targeting and minimize drug

A novel strategy for hemolytic uremic syndrome: successful treatment with thrombomodulin α.

PubMed

Honda, Takashi; Ogata, Shohei; Mineo, Eri; Nagamori, Yukako; Nakamura, Shinya; Bando, Yuki; Ishii, Masahiro

2013-03-01

Hemolytic uremic syndrome (HUS) is a life-threatening infectious disease in childhood for which there is no confirmed therapeutic strategy. Endothelial inflammation leading to microthrombosis formation via complement activation is the main pathology of HUS. Thrombomodulin is an endothelial membrane protein that has anticoagulation and anti-inflammatory effects, including the suppression of complement activity. Recombinant human soluble thrombomodulin (rTM) is a novel therapeutic medicine for disseminated intravascular coagulation. We administered rTM to 3 patients with HUS for 7 days and investigated the outcomes in view of the patients' prognoses, changes in biochemical markers, complications, and adverse effects of rTM. Symptoms and laboratory data improved after initiation of rTM in all 3 patients. Abnormal activation of complements was also dramatically suppressed in 1 patient. The patients recovered without any complications or adverse effects of rTM. They were discharged having normal neurologic status and with no renal dysfunction. To our knowledge, this is the first report of rTM being used to treat HUS. These case reports show the positive effect of rTM in patients with HUS. Randomized controlled studies should be performed to assess the efficacy and safety of rTM for children with HUS.

A Rare Non-Hemolytic Case of Idiopathic Cold Agglutinin Disease.

PubMed

Erkus, Edip; Kocak, Mehmet Z; Aktas, Gulali; Ozen, Mehmet; Atak, Burcin M; Duman, Tuba T; Tekce, Buket K; Savli, Haluk

2018-06-01

Cold agglutinin disease is a very rare condition associated with agglutination of erythrocytes in cold environment usually due to IgM type antibodies. Other than hemolytic anemias, it may interfere with routine hemogram tests due to miscalculation of red blood cell count (RBC) and other hemogram parameters calculated with involvement of RBC. Awareness of the condition is important to overcome laboratory errors. We studied a peripheral blood smear and repeated the hemogram test at 37°C to establish the diagnosis of cold agglutinin disease. Initial hemogram test results of the fifty-eight year-old man was as follows: RBC: 1.34 M/µL, hemoglobin (Hb): 12.4 g/dL, hematocrit (Htc): 11.8%, mean corpuscular hemoglobin (MCH): 92.4 pg, and mean corpuscular hemoglobin concentration (MCHC): 105 gr/dL. Despite the standard indirect Coombs test being negative, repeated tests at room temperature was 4+. We suspected cold agglutinin disease and repeated the hemogram test using the Bain-Marie method at 37°C and the test results showed RBC: 3.4 M/µL, hemoglobin: 12.6 g/dL, hematocrit: 30.2%, MCH: 31.7 pg, and MCHC: 41.8 g/dL. Inappropriate hemogram results may be a sign of underlying cold agglutinin disease. Hemolytic anemia not always accompanies the disease; however, cold exposure may trigger erythrocyte agglutination in vitro and may cause erratic laboratory results.

[Establishment and validation of a neonatal pig model of hemolytic jaundice].

PubMed

Li, Yong-Fu; Ma, Yue-Lan; Nie, Ling; Chen, Shuan; Jin, Mei-Fang; Wang, San-Lan

2016-05-01

To establish a neonatal pig model of hemolytic jaundice. Twelve seven-day-old purebred Yorkshire pigs were randomly divided into an experimental group and a control group (n=6 each). Immunization of New Zealand white rabbits was used to prepare rabbit anti-porcine red blood cell antibodies, and rabbit anti-porcine red blood cell serum was separated. The neonatal pigs in the experimental group were given an intravenous injection of rabbit anti-porcine red blood cell serum (5 mL), and those in the control group were given an intravenous injection of normal saline (5 mL). Venous blood samples were collected every 6 hours for routine blood test and liver function evaluation. The experimental group had a significantly higher serum bilirubin level than the control group at 18 hours after the injection of rabbit anti-porcine red blood cell serum (64±30 μmol/L vs 20±4 μmol/L; P<0.05). In the experimental group, the serum bilirubin level reached the peak at 48 hours (275±31 μmol/L), and decreased significantly at 96 hours after the injection (95±17 μmol/L), but all significantly higher than that in the control group (P<0.05). At 18 hours after the injection, the experimental group had a significantly lower red blood cell (RBC) count than the control group [(4.58±0.32)×10(12)/L vs (5.09±0.44)×10(12)/L; P<0.05]; at 24 hours, the experimental group showed further reductions in RBC count and hemoglobin level and had significantly lower RBC count and hemoglobin level than the control group [RBC: (4.21±0.24)×10(12)/L vs (5.11±0.39)×10(12)/L, P<0.05; hemoglobin: 87±3 g vs 97±6 g, P<0.05]. The differences in RBC count and hemoglobin level between the two groups were largest at 36-48 hours. The neonatal pig model of hemolytic jaundice simulates the pathological process of human hemolytic jaundice well and provides good biological and material bases for further investigation of neonatal hemolysis.

Recent insights in the use of nanocarriers for the oral delivery of bioactive proteins and peptides.

PubMed

Batista, Patrícia; Castro, Pedro M; Madureira, Ana Raquel; Sarmento, Bruno; Pintado, Manuela

2018-03-01

Bioactive proteins and peptides have been used with either prophylactic or therapeutic purposes, presenting inherent advantages as high specificity and biocompatibility. Nanocarriers play an important role in the stabilization of proteins and peptides, offering enhanced buccal permeation and protection while crossing the gastrointestinal tract. Moreover, preparation of nanoparticles as oral delivery systems for proteins/peptides may include tailored formulation along with functionalization aiming bioavailability enhancement of carried proteins or peptides. Oral delivery systems, namely buccal delivery systems, represent an interesting alternative route to parenteric delivery systems to carry proteins and peptides, resulting in higher comfort of administration and, therefore, compliance to treatment. This paper outlines an extensive overview of the existing publications on proteins/peptides oral nanocarriers delivery systems, with special focus on buccal route. Manufacturing aspects of most commonly used nanoparticles for oral delivery (e.g. polymeric nanoparticles using synthetic or natural polymers and lipid nanoparticles) advantages and limitations and potential applications of nanoparticles as proteins/peptides delivery systems will also be thoroughly addressed. Copyright © 2018 Elsevier Inc. All rights reserved.

Rationally designed nanocarriers for intranasaltherapy of allergic rhinitis: influence of carrier type on in vivo nasal deposition

PubMed Central

Sallam, Marwa Ahmed; Helal, Hala Mahmoud; Mortada, Sana Mohamed

2016-01-01

The aim of this study is to develop a locally acting nasal delivery system of triamcinolone acetonide (TA) for the maintenance therapy of allergic rhinitis. The effect of encapsulating TA in different nanocarriers on its mucosal permeation and retention as well as in vivo nasal deposition has been studied. A comparative study was established between polymeric oil core nanocapsules (NCs), lipid nanocarriers such as nanoemulsion (NE), and nanostructured lipid carriers (NLCs). The elaborated nanocarriers were compared with TA suspension and the commercially available suspension “Nasacort®”. The study revealed that NC provided the highest mucosal retention, as 46.14%±0.048% of the TA initial dose was retained after 24 hours, while showing the least permeation through the nasal mucosa. On the other hand, for TA suspension and Nasacort®, the mucosal retention did not exceed 23.5%±0.047% of the initial dose after 24 hours. For NE and NLC, values of mucosal retention were 19.4%±0.041% and 10.97%±0.13%, respectively. NC also showed lower mucosal irritation and superior stability compared with NE. The in vivo nasal deposition study demonstrated that NC maintained drug in its site of action (nasal cavity mucosa) for the longest period of time. The elaborated polymeric oil core NCs are efficient carriers for the administration of nasally acting TA as it produced the least permeation results, thus decreasing systemic absorption of TA. Although NCs have been administered via various routes, this is the first study to implement the polymeric oil core NC as an efficient carrier for localized nasal drug delivery. PMID:27307734

[Aortic stenosis and mitral regurgitation complicated by hemolytic anemia and positive Direct Coombs test: a case report].

PubMed

Tamura, Shinjiro; Kitaoka, Hiroaki; Yamasaki, Naohito; Okawa, Makoto; Kubo, Toru; Matsumura, Yoshihisa; Furuno, Takashi; Takata, Jun; Nishinaga, Masanori; Sasaguri, Shiro; Doi, Yoshinori

2005-09-01

A 83-year-old man was admitted because of heart failure due to severe aortic stenosis and mitral regurgitation secondary to chordal rupture of the anterior leaflet. Mild anemia and elevated serum lactate dehydrogenase were present with reticulocytosis and haptoglobinemia. Direct Coombs test was positive. Coexistence of autoimmune hemolytic anemia was identified, but the main cause of his hemolysis was thought to be mechanical hemolysis due to stenotic valve and/or ruptured chordae because of the presence of red cell fragmentation. The patient successfully underwent double valve replacement. Improvement of anemia was coupled with reduction of the serum lactate dehydrogenase level. Valvular shear stress on the red cells and reduction of red cell deformability secondary to autoimmune hemolytic anemia were thought to be responsible for his hemolysis.

Antibacterial, anti-inflammatory, and bone-regenerative dual-drug-loaded calcium phosphate nanocarriers-in vitro and in vivo studies.

PubMed

Madhumathi, K; Rubaiya, Y; Doble, Mukesh; Venkateswari, R; Sampath Kumar, T S

2018-05-01

A dual local drug delivery system (DDS) composed of calcium phosphate bioceramic nanocarriers aimed at treating the antibacterial, anti-inflammatory, and bone-regenerative aspects of periodontitis has been developed. Calcium-deficient hydroxyapatite (CDHA, Ca/P = 1.61) and tricalcium phosphate (β-TCP) were prepared by microwave-accelerated wet chemical synthesis method. The phase purity of the nanocarriers was confirmed by x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR), while the transmission electron microscopy (TEM) confirmed their nanosized morphology. CDHA was selected as carrier for the antibiotic (tetracycline) while TCP was chosen as the anti-inflammatory drug (ibuprofen) carrier. Combined drug release profile was studied in vitro from CDHA/TCP (CTP) system and compared with a HA/TCP (BCP) biphasic system. The tetracycline and ibuprofen release rate was 71 and 23% from CTP system as compared to 63 and 20% from BCP system. CTP system also showed a more controlled drug release profile compared to BCP system. Modeling of drug release kinetics from CTP system indicated that the release follows Higuchi model with a non-typical Fickian diffusion profile. In vitro biological studies showed the CTP system to be biocompatible with significant antibacterial and anti-inflammatory activity. In vivo implantation studies on rat cranial defects showed greater bone healing and new bone formation in the drug-loaded CTP system compared to control (no carrier) at the end of 12 weeks. The in vitro and in vivo results suggest that the combined drug delivery platform can provide a comprehensive management for all bone infections requiring multi-drug therapy.

Scalable imprinting of shape-specific polymeric nanocarriers using a release layer of switchable water solubility.

PubMed

Agarwal, Rachit; Singh, Vikramjit; Jurney, Patrick; Shi, Li; Sreenivasan, S V; Roy, Krishnendu

2012-03-27

There is increasing interest in fabricating shape-specific polymeric nano- and microparticles for efficient delivery of drugs and imaging agents. The size and shape of these particles could significantly influence their transport properties and play an important role in in vivo biodistribution, targeting, and cellular uptake. Nanoimprint lithography methods, such as jet-and-flash imprint lithography (J-FIL), provide versatile top-down processes to fabricate shape-specific, biocompatible nanoscale hydrogels that can deliver therapeutic and diagnostic molecules in response to disease-specific cues. However, the key challenges in top-down fabrication of such nanocarriers are scalable imprinting with biological and biocompatible materials, ease of particle-surface modification using both aqueous and organic chemistry as well as simple yet biocompatible harvesting. Here we report that a biopolymer-based sacrificial release layer in combination with improved nanocarrier-material formulation can address these challenges. The sacrificial layer improves scalability and ease of imprint-surface modification due to its switchable solubility through simple ion exchange between monovalent and divalent cations. This process enables large-scale bionanoimprinting and efficient, one-step harvesting of hydrogel nanoparticles in both water- and organic-based imprint solutions. © 2012 American Chemical Society

A Unique Triad: Ulcerative Colitis, Primary Sclerosing Cholangitis, and Autoimmune Hemolytic Anemia.

PubMed

Naqvi, Syeda; Hasan, Syed Askari; Khalid, Sameen; Abbass, Aamer; Albors-Mora, Melanie

2018-01-15

Ulcerative colitis is an autoimmune disorder leading to chronic intestinal inflammation. It can present with a wide range of associated extra-intestinal manifestations. We present a case of an 18-year-old man diagnosed with ulcerative colitis, autoimmune hemolytic anemia and primary sclerosing cholangitis during the same hospitalization. The unique triad of these diseases gives important clues to the immunological factors involved in the pathogenesis of these diseases.

Pernicious Anemia with Autoimmune Hemolytic Anemia: A Case Report and Literature Review

PubMed Central

Manchandani, Raj Pal; Oneal, Patricia

2016-01-01

Pernicious anemia is a common cause of vitamin B12 deficiency. Here, we discuss a case of a young woman who presented with severe anemia along with a history of iron deficiency anemia. After a review of her clinical presentation and laboratory data, we identified an autoimmune hemolytic anemia and a concomitant pernicious anemia. The concurrence of both these hematological diagnoses in a patient is rare. PMID:27559485

Preparation and evaluation of novel mixed micelles as nanocarriers for intravenous delivery of propofol

NASA Astrophysics Data System (ADS)

Li, Xinru; Zhang, Yanhui; Fan, Yating; Zhou, Yanxia; Wang, Xiaoning; Fan, Chao; Liu, Yan; Zhang, Qiang

2011-12-01

Novel mixed polymeric micelles formed from biocompatible polymers, poly(ethylene glycol)-poly(lactide) (mPEG-PLA) and polyoxyethylene-660-12-hydroxy stearate (Solutol HS15), were fabricated and used as a nanocarrier for solubilizing poorly soluble anesthetic drug propofol. The solubilization of propofol by the mixed micelles was more efficient than those made of mPEG-PLA alone. Micelles with the optimized composition of mPEG-PLA/Solutol HS15/propofol = 10/1/5 by weight had particle size of about 101 nm with narrow distribution (polydispersity index of about 0.12). Stability analysis of the mixed micelles in bovine serum albumin (BSA) solution indicated that the diblock copolymer mPEG efficiently protected the BSA adsorption on the mixed micelles because the hydrophobic groups of the copolymer were efficiently screened by mPEG, and propofol-loaded mixed micelles were stable upon storage for at least 6 months. The content of free propofol in the aqueous phase for mixed micelles was lower by 74% than that for the commercial lipid emulsion. No significant differences in times to unconsciousness and recovery of righting reflex were observed between mixed micelles and commercial lipid formulation. The pharmacological effect may serve as pharmaceutical nanocarriers with improved solubilization capacity for poorly soluble drugs.

Clinical and molecular epidemiology of beta-hemolytic streptococcal infections in India.

PubMed

Mathur, Purva; Bhardwaj, Nidhi; Mathur, Kushal; Behera, Bijayini; Gupta, Gunjan; Kapil, Arti; Singh, Sarman; Misra, Mahesh Chandra

2014-03-13

Beta-hemolytic streptococci (βHS) cause a diverse array of human infections. Despite the high number of cases of streptococcal carriers and diseases, studies discerning the molecular epidemiology of βHS in India are limited. This study reports the molecular and clinical epidemiology of beta-hemolytic streptococcal infections from two geographically distinct regions of India. A total of 186 isolates of βHS from north and south India were included. The isolates were identified to species level and subjected to antimicrobial susceptibility testing. Polymerase chain reaction (PCR) was done to detect exotoxin genes, and emm types of group A streptococci (GAS) strains were ascertained by sequencing. GAS was the most common isolate (71.5%), followed by group G streptococci (GGS) (21%). A large proportion of GAS produced speB (97%), smeZ (89%), speF (91%), and speG (84%). SmeZ was produced by 21% and 50% of GGS and GGS, respectively. A total of 45 different emm types/subtypes were seen in GAS, with emm 11 being the most common. Resistance to tetracycline (73%) and erythromycin (34.5%) was commonly seen in GAS. A high diversity of emm types was seen in Indian GAS isolates with high macrolide and tetracycline resistance. SpeA was less commonly seen in Indian GAS isolates. There was no association between disease severity and exotoxin gene production.

Current Progress in Gene Delivery Technology Based on Chemical Methods and Nano-carriers

PubMed Central

Jin, Lian; Zeng, Xin; Liu, Ming; Deng, Yan; He, Nongyue

2014-01-01

Gene transfer methods are promising in the field of gene therapy. Current methods for gene transfer include three major groups: viral, physical and chemical methods. This review mainly summarizes development of several types of chemical methods for gene transfer in vitro and in vivo by means of nano-carriers like; calcium phosphates, lipids, and cationic polymers including chitosan, polyethylenimine, polyamidoamine dendrimers, and poly(lactide-co-glycolide). This review also briefly introduces applications of these chemical methods for gene delivery. PMID:24505233

DPPC/poly(2-methyl-2-oxazoline)-grad-poly(2-phenyl-2-oxazoline) chimeric nanostructures as potential drug nanocarriers

NASA Astrophysics Data System (ADS)

Pippa, Natassa; Kaditi, Eleni; Pispas, Stergios; Demetzos, Costas

2013-06-01

In this study, we report on the self assembly behavior and on stability studies of mixed (chimeric) nanosystems consisting of dipalmitoylphosphatidylcholine (DPPC) and poly(2-methyl-2-oxazoline)-grad-poly(2-phenyl-2-oxazoline) (MPOx) gradient copolymer in aqueous media and in fetal bovine serum (FBS). A gamut of light scattering techniques and fluorescence spectroscopy were used in order to extract information on the size and morphological characteristics of the nanoassemblies formed, as a function of gradient block copolymer content, as well as temperature. The hydrodynamic radii ( R h) of nanoassemblies decreased in the process of heating up to 50 °C, while the fractal dimension ( d f) values, also increased. Indomethacin was successfully incorporated into these chimeric nanocarriers. Drug release was depended on the components ratio. The present studies show that there are a number of parameters that can be used in order to alter the properties of chimeric nanosystems, and this is advantageous to the development of "smart" nanocarriers for drug delivery.

[Tonsillopharyngitis outbreak caused by foodborne group A beta-hemolytic Streptococcus].

PubMed

Nieto Vera, Juan; Figueroa Murillo, Estrella; Cruz Calderón, María Victoria; Pérez Alonso, Aránzazu

2011-08-01

Although infrequent, some authors have reported outbreaks of foodborne tonsillopharyngitis. On May 11, 2010 a series of cases of tonsillopharyngitis among those attending a fellowship meeting on 8 March was notified to the Epidemiological Surveillance Network in Andalusia (SVEA). The aim of this study is to epidemiologically characterise the outbreak. Descriptive analysis of reported cases and case - control exposure to the implicated food. The variables taken into account were age, sex, symptoms and start date. Sources of information used were the records of the SVEA and individual digital report (DIRAYA). Frequencies and attack rates were calculated, and a Bayesian analysis for the comparison of difference in proportions of disease was carried out for a 95% probability or credibility range (IP). Among the 130 attendees at a communion 41 cases of tonsillopharyngitis (attack rate 31.5%) were detected, and in smears Group A Beta-Hemolytic Streptococcus was isolated. The most affected age group was the 25-44 year-olds, 16 (39,0%); 68.6% (24) female. The egg salad showed a probability greater than 80% P(Δ>0.10 and Δ>0.15) for a 95% IP of risk of disease after intake and a probability of having a lower risk of no disease. It was a Group A Beta-Hemolytic Streptococcal outbreak, the epidemiological evidence indicates exposure to common single source, hence the hypothesis of dietary origin, the implicated food was egg salad. Contributing factors could be cross-contamination after preparation favoured by the bad practice and the conditions of the place.

Hypothesis: Hemolytic Transfusion Reactions Represent an Alternative Type of Anaphylaxis

PubMed Central

Hod, Eldad A.; Sokol, Set A.; Zimring, James C.; Spitalnik, Steven L.

2009-01-01

Classical anaphylaxis is the most severe, and potentially fatal, type of allergic reaction, manifested by hypotension, bronchoconstriction, and vascular permeability. Similarly, a hemolytic transfusion reaction (HTR) is the most feared consequence of blood transfusion. Evidence for the existence of an alternative, IgG-mediated pathway of anaphylaxis may be relevant for explaining the pathophysiology of IgG-mediated-HTRs. The purpose of this review is to summarize the evidence for this alternative pathway of anaphylaxis and to present the hypothesis that an IgG-mediated HTR is one example of this type of anaphylaxis. PMID:18830382

From the Cover: Potentiation of Drug-Induced Phospholipidosis In Vitro through PEGlyated Graphene Oxide as the Nanocarrier.

PubMed

Yang, Liecheng; Zhong, Xiaoyan; Li, Qian; Zhang, Xihui; Wang, Yangyun; Yang, Kai; Zhang, Leshuai W

2017-03-01

Cationic amphiphilic drugs (CADs) are small molecules that can induce phospholipidosis (PLD), causing the intracellular accumulation of phospholipid in the lamellar bodies. Nanotechnology based drug delivery systems have been used widely, while it is unknown if drug-induced PLD (DIP) can be potentiated through drug retention by indigestible nanocarriers. Due to the high drug loading capacity of graphene, we investigated if PEGylated graphene oxide (PEG-GO) loaded with CAD could potentiate DIP. Tamoxifen induced the accumulation of NBD-PE, a fluorescence labeled phospholipid in human hepatoma HepG2 cells, while PEG-GO loaded with tamoxifen (PEG-GO/tamoxifen) further potentiated PLD. PEG-GO/tamoxifen induced more gene expression of PLD marker than tamoxifen alone. PEG-GO enhanced DIP was also observed for other CAD, indicating that nanocarrier potentiated DIP could be universal. More lamellar bodies were observed in PEG-GO/tamoxifen treated cells than tamoxifen alone by transmission electron microscopy. When compared with tamoxifen alone, PEG-GO/tamoxifen showed a delayed but potent PLD. In addition, the retarded PLD recovery by PEG-GO/tamoxifen indicated that the reversibility of DIP was interfered. Confocal microscopy revealed the increased number of lysosomes, greater expression of lysosomal associated membrane protein 2 (LAMP2) (a PLD marker), and an increase in the co-localization between lysosome/LAMP2 and NBD-PE by PEG-GO/tamoxifen rather than tamoxifen alone. Finally, we found that PEG-GO or/and tamoxifen-induced PLD seemed to have no correlation with autophagy. This research suggests pharmaceutical companies and regulatory agencies that if nanoparticles are used as the vectors for drug delivery, the adverse drug effects may be further potentiated probably through the long-term accumulation of nanocarriers. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e

Effect of cationic side-chains on intracellular delivery and cytotoxicity of pH sensitive polymer-doxorubicin nanocarriers.

PubMed

Fang, Chen; Kievit, Forrest M; Cho, Yong-Chan; Mok, Hyejung; Press, Oliver W; Zhang, Miqin

2012-11-21

Fine-tuning the design of polymer-doxorubicin conjugates permits optimization of an efficient nanocarrier to greatly increase intracellular uptake and cytotoxicity. Here, we report synthesis of a family of self-assembled polymer-doxorubicin nanoparticles and an evaluation of the effects of various types of side-chains on intracellular uptake and cytotoxicity of the nanocarriers for lymphoma cells. Monomers with three different cationic side-chains (CA) and pK(a)'s, i.e., a guanidinium group (Ag), an imidazole group (Im), and a tertiary amine group (Dm), were comparatively investigated. The cationic monomer, poly(ethylene glycol) (PEG), and doxorubicin (Dox) were reacted with 1,4-(butanediol) diacrylate (BUDA) to prepare a poly(β-amino ester) (PBAE) polymer via Michael addition. All three polymer-Dox conjugates spontaneously formed nanoparticles (NP) through hydrophobic interactions between doxorubicin in aqueous solution, resulting in NP-Im/Dox, NP-Ag/Dox, and NP-Dm/Dox, with hydrodynamic sizes below 80 nm. Doxorubicin was linked to all 3 types of NPs with a hydrazone bond to assure selective release of doxorubicin only at acidic pH, as it occurs in the tumor microenvironment. Both NP-Im/Dox and NP-Ag/Dox exhibited much higher intracellular uptake by Ramos cells (Burkitt's lymphoma) than NP-Dm/Dox, suggesting that the type of side chain in the NPs determines the extent of intracellular uptake. As a result, NP-Im/Dox and NP-Ag/Dox showed cytotoxicity that was comparable to free Dox in vitro. Our findings suggest that the nature of surface cationic group on nanocarriers may profoundly influence their intracellular trafficking and resulting therapeutic efficacy. Thus, it is a crucial factor to be considered in the design of novel carriers for intracellular drug delivery.

Effect of cationic side-chains on intracellular delivery and cytotoxicity of pH sensitive polymer-doxorubicin nanocarriers

NASA Astrophysics Data System (ADS)

Fang, Chen; Kievit, Forrest M.; Cho, Yong-Chan; Mok, Hyejung; Press, Oliver W.; Zhang, Miqin

2012-10-01

Fine-tuning the design of polymer-doxorubicin conjugates permits optimization of an efficient nanocarrier to greatly increase intracellular uptake and cytotoxicity. Here, we report synthesis of a family of self-assembled polymer-doxorubicin nanoparticles and an evaluation of the effects of various types of side-chains on intracellular uptake and cytotoxicity of the nanocarriers for lymphoma cells. Monomers with three different cationic side-chains (CA) and pKa's, i.e., a guanidinium group (Ag), an imidazole group (Im), and a tertiary amine group (Dm), were comparatively investigated. The cationic monomer, poly(ethylene glycol) (PEG), and doxorubicin (Dox) were reacted with 1,4-(butanediol) diacrylate (BUDA) to prepare a poly(β-amino ester) (PBAE) polymer via Michael addition. All three polymer-Dox conjugates spontaneously formed nanoparticles (NP) through hydrophobic interactions between doxorubicin in aqueous solution, resulting in NP-Im/Dox, NP-Ag/Dox, and NP-Dm/Dox, with hydrodynamic sizes below 80 nm. Doxorubicin was linked to all 3 types of NPs with a hydrazone bond to assure selective release of doxorubicin only at acidic pH, as it occurs in the tumor microenvironment. Both NP-Im/Dox and NP-Ag/Dox exhibited much higher intracellular uptake by Ramos cells (Burkitt's lymphoma) than NP-Dm/Dox, suggesting that the type of side chain in the NPs determines the extent of intracellular uptake. As a result, NP-Im/Dox and NP-Ag/Dox showed cytotoxicity that was comparable to free Dox in vitro. Our findings suggest that the nature of surface cationic group on nanocarriers may profoundly influence their intracellular trafficking and resulting therapeutic efficacy. Thus, it is a crucial factor to be considered in the design of novel carriers for intracellular drug delivery.

Lipid nanocarriers (GeluPearl) containing amphiphilic lipid Gelucire 50/13 as a novel stabilizer: fabrication, characterization and evaluation for oral drug delivery

NASA Astrophysics Data System (ADS)

Date, Abhijit A.; Vador, Nimish; Jagtap, Aarti; Nagarsenker, Mangal S.

2011-07-01

Purpose. To evaluate the ability of Gelucire 50/13 (an amphiphilic lipid excipient) to act as a stabilizer for lipid nanocarriers such as solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) and to establish the ability of Gelucire 50/13 based lipid nanocarriers to improve oral delivery of hydrophobic drugs using repaglinide (RPG) as a model drug. Methods. The ability of Gelucire 50/13 to nanosize various solid lipids was evaluated. The ability of Gelucire 50/13 to yield NLC was evaluated by using Precirol ATO 5 as a model solid lipid and various liquid lipids (oils). Gelucire 50/13 based NLC (GeluPearl) were evaluated for their ability to improve the efficacy of RPG on oral administration in comparison to RPG tablets. The short term stability of RPG-GeluPearl was evaluated at 25 °C/60% RH. Results. Gelucire 50/13 could successfully yield SLN and NLC of various solid lipids, demonstrating its potential to act as a novel stabilizer. DSC studies indicated that Gelucire 50/13 interacts with Precirol ATO 5 and this interaction suppresses polymorphic transitions of both the components. RPG-GeluPearl exhibited significantly higher anti-diabetic activity compared to marketed RPG tablets. RPG-GeluPearl demonstrated good colloidal and chemical stability at the end of 1 month. Indian patent application number 2167/MUM/2008.

Efficient Self-Assembly of mPEG End-Capped Porous Silica as a Redox-Sensitive Nanocarrier for Controlled Doxorubicin Delivery.

PubMed

Nguyen, Anh Khoa; Nguyen, Thi Hiep; Bao, Bui Quoc; Bach, Long Giang; Nguyen, Dai Hai

2018-01-01

Porous nanosilica (PNS) has been regarded as a promising candidate for controlled delivery of anticancer drugs. Unmodified PNS-based nanocarriers, however, showed a burst release of encapsulated drugs, which may limit their clinical uses. In this report, PNS was surface conjugated with adamantylamine (ADA) via disulfide bridges (-SS-), PNS-SS-ADA, which was further modified with cyclodextrin-poly(ethylene glycol) methyl ether conjugate (CD-mPEG) to form a core@shell structure PNS-SS-ADA@CD-mPEG for redox triggered delivery of doxorubicin (DOX), DOX/PNS-SS-ADA@CD-mPEG. The prepared PNS-SS-ADA@CD-mPEG nanoparticles were spherical in shape with an average diameter of 55.5 ± 3.05 nm, a little larger than their parentally PNS nanocarriers, at 49.6 ± 2.56 nm. In addition, these nanoparticles possessed high drug loading capacity, at 79.2 ± 3.2%, for controlled release. The release of DOX from DOX/PNS-SS-ADA@CD-mPEG nanoparticles was controlled and prolonged up to 120 h in PBS medium (pH 7.4), compared to less than 40 h under reducing condition of 5 mM DTT. Notably, the PNS-SS-ADA@CD-mPEG was a biocompatible nanocarrier, and the toxicity of DOX was dramatically reduced after loading drugs into the porous core. This redox-sensitive PNS-SS-ADA@CD-mPEG nanoparticle could be considered a potential candidate with high drug loading capacity and a lower risk of systemic toxicity.

Hemolytic Uremic Syndrome-associated Encephalopathy Successfully Treated with Corticosteroids.

PubMed

Hosaka, Takashi; Nakamagoe, Kiyotaka; Tamaoka, Akira

2017-11-01

The encephalopathy that occurs in association with hemolytic uremic syndrome (HUS), which is caused by enterohemorrhagic Escherichia coli (E. coli), has a high mortality rate and patients sometimes present sequelae. We herein describe the case of a 20-year-old woman who developed encephalopathy during the convalescent stage of HUS caused by E.coli O26. Hyperintense lesions were detected in the pons, basal ganglia, and cortex on diffusion-weighted brain MRI. From the onset of HUS encephalopathy, we treated the patient with methylprednisolone (mPSL) pulse therapy alone. Her condition improved, and she did not present sequelae. Our study shows that corticosteroids appear to be effective for the treatment of some patients with HUS encephalopathy.

Parvovirus B19 infection presenting with severe erythroid aplastic crisis during pregnancy in a woman with autoimmune hemolytic anemia and alpha-thalassemia trait: a case report.

PubMed

Chen, Chi-Ching; Chen, Chin-Shan; Wang, Wei-Yao; Ma, Jui-Shan; Shu, Hwei-Fan; Fan, Frank S

2015-03-12

Parvovirus B19 virus commonly causes subclinical infection, but it can prove fatal to the fetus during pregnancy and cause severe anemia in an adult with hemolytic diseases. We present the case of a woman with autoimmune hemolytic anemia who was diagnosed with parvovirus B19-induced transient aplastic crisis during her second trimester of pregnancy and faced the high risk of both fetal and maternal complications related to this specific viral infection. To the best of our knowledge, the experience of successful intravenous immunoglobulin treatment for B19 virus infection during pregnancy, as in our case, is limited. A 28-year-old and 20-week pregnant Chinese woman with genetically confirmed alpha-thalassemia trait was diagnosed with cold antibody autoimmune hemolytic anemia and suffered from transient aplastic crisis caused by B19 virus infection. She received intravenous immunoglobulin treatment to reduce the risk of hydrops fetalis. Her peripheral blood reticulocyte percentage recovered, but anemia persisted, so she underwent several courses of high dose intravenous dexamethasone for controlling her underlying hemolytic problem. Finally, her hemoglobin levels remained stable with no need of erythrocyte transfusion, and a healthy baby boy was naturally delivered. Parvovirus B19 virus infection should be considered when a sudden exacerbation of anemia occurs in a patient with hemolytic disease, and the possible fetal complications caused by maternal B19 virus infection during pregnancy should not be ignored. Close monitoring and adequate management can keep both mother and fetus safe.

Effect of Dendritic Polymer Architecture on Biological Behaviors of Self-Assembled Nanocarriers

NASA Astrophysics Data System (ADS)

Hsu, Hao-Jui

Polymeric self-assembled nanocarriers represent one of the most versatile platforms for drug delivery. Through tailoring the physiochemical properties of amphiphilic block copolymers, self-assembled nanocarriers with great thermodynamic stability and desired biological properties could be achieved. The PEGylated dendron-based copolymers (PDCs) are one of the novel amphiphilic copolymers that have attracted a great deal of scientific interest due to their unique dendritic structure and properties. While the dendritic polymer architecture of PDC has been shown to enhance the thermodynamic stability of the self-assembling PDCs, dendron micelles, the effect of this polymer architecture on the biological properties of dendron micelles has not yet been studied. Therefore, this dissertation research is focused on understanding the role of dendritic polymer structure on moderating the biological properties of various self-assembled nanocarriers. To systematically investigate this, three studies have been designed and performed. First, we studied whether the dendritic structure of PDC allows dendron micelles to behave non-specific cellular interactions in a similar way that dendrimers would do. Second, cell-specific interactions of dendron micelles mediated by conjugated ligands were investigated. Third, we investigated the influence of dendritic PEG outer shell on micelle-serum protein interactions and its subsequent implication. Our results revealed that both non-specific and specific cellular interactions of dendron micelles were controllable through modulation of the PEG corona length. While the non-specific charge-dependent cellular interactions of dendron micelles were tunable through controlling the length of PEG corona, the use of long PEG tether was found to enhance the ligand-mediated cellular interactions of dendron micelles. With the ligand tethers, a 27-fold enhancement in ligand-mediated cellular interactions can be achieved, compared to non-targeted dendron

Effects of self washout structure on the antithrombogenicity and the hemolytic properties of a centrifugal pump.

PubMed

Wakisaka, Y; Taenaka, Y; Araki, K; Chikanari, K; Nakatani, T; Baba, Y; Anai, H; Eya, K; Toda, K; Takano, H

1997-02-01

Antithrombogenicity in an initial type (N1) of a centrifugal pump (CP) developed in our institute is provided by the central balancing hole of an impeller. A new CP (N2) was modified to obtain better antithrombogenicity, in which the balancing hole was widened to improve self washout flow velocity (Vsf), and an edge of the thrust bearing was rounded off to minimize flow separation. Effects of the modifications were assessed in vitro and in vivo studies. The Vsf of the N1 and the N2 evaluated by a Doppler velocimeter were 12.8 and 22.1 cm/s, respectively. Flow around the thrust bearing, which was visualized by a light cutting method, confirmed less flow stagnation in the N2. The hemolytic indices of the N1 and the N2 were 0.023 and 0.008 mg/dl, respectively. In vivo antithrombogenicity and the hemolytic properties of the N2 and the N1 were investigated without anticoagulation therapy in 3 goats. In each goat the N2 was driven for 1 week and exchanged for the N1, which was driven for the same period. Red thrombi at the thrust bearing were found in 2 N1s, and 2 small thrombi were on the impeller of another N1, whereas a thrombus of less than 1 mm3 at the TB was noted in 1 N2. Plasma free hemoglobin was not increased in either CP. These results indicate that the N2 has better antithrombogenicity and hemolytic properties than the N1.

A Review on Potential of Proteins as an Excipient for Developing a Nano-Carrier Delivery System.

PubMed

Chakraborty, Amrita; Dhar, Pubali

2017-01-01

In neo-age research, nano-materials have emerged as potential tools for the revolution of diagnostic and therapeutic field because of their nano-scale effects, increased surface area-volume ratio, and other beneficial properties. For the last few decades, protein has been regarded as the most attractive and versatile natural bio-macromolecule among all of the available biopolymers. Protein is largely exploited as a nano-carrier system in the pharmaceutical industry due to its low cytotoxocity, biocompatibility, biodegradability, abundant renewable sources, significant attaching ability, clinically useful targeting, and site-specific efficient uptake. This review mainly emphasizes on the latest development and progress achieved in the utilization of protein as a nano-vehicle for a large number of therapeutics such as drugs, genes, hormones, enzymse, nutraceuticals, antibodies, peptides, etc. We also discuss the sources of protein materials, fabrication aspects, advantages, constraints, in vivo and in vitro studies and provide a comparative analysis between the different types of proteins as nano-carriers. The variation of the release pattern and molecular mechanism of the encapsulated molecule with respect to different protein types and various nano-structures are also highlighted here to explore the enormous promises of this novel approach.

Novel fluconazole derivatives with promising antifungal activity.

PubMed

Thamban Chandrika, Nishad; Shrestha, Sanjib K; Ngo, Huy X; Howard, Kaitlind C; Garneau-Tsodikova, Sylvie

2018-02-01

The fungistatic nature and toxicity concern associated with the azole drugs currently on the market have resulted in an increased demand for new azole antifungal agents for which these problematic characteristics do not exist. The extensive use of azoles has resulted in fungal strains capable of resisting the action of these drugs. Herein, we report the synthesis and antifungal activity of novel fluconazole (FLC) analogues with alkyl-, aryl-, cycloalkyl-, and dialkyl-amino substituents. We evaluated their antifungal activity by MIC determination and time-kill assay as well as their safety profile by hemolytic activity against murine erythrocytes as well as cytotoxicity against mammalian cells. The best compounds from our study exhibited broad-spectrum activity against most of the fungal strains tested, with excellent MIC values against a number of clinical isolates. The most promising compounds were found to be less hemolytic than the least hemolytic FDA-approved azole antifungal agent voriconazole (VOR). Finally, we demonstrated that the synthetic alkyl-amino FLC analogues displayed chain-dependent fungal membrane disruption as well as inhibition of ergosterol biosynthesis as possible mechanisms of action. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Difficulties in the diagnosis of diarrhea-associated hemolytic uremic syndrome in adults].

PubMed

Malov, V A; Maleev, V V; Kozlovskaya, N L; Tsvetkova, N A; Smetanina, S V; Gorobchenko, A N; Serova, V V; Chentsov, V B; Volkov, A G; Faller, A P

Hemolytic uremic syndrome (HUS) is a rare, but menacing condition registered mainly in children. The paper gives a detailed description and analysis of a clinical case of HUS with a favorable outcome in an adult woman who developed the syndrome in the presence of bloody diarrhea. It considers an update on the etiology, pathogenesis, and clinical features of HUS associated with diarrheal syndrome and discusses differential diagnostic features, diagnostic problems, and characteristics of management tactics for patients.

Exacerbation of autoimmune hemolytic anemia induced by the first dose of programmed death-1 inhibitor pembrolizumab: a case report.

PubMed

Ogawa, Kenta; Ito, Jiro; Fujimoto, Daichi; Morita, Mari; Yoshizumi, Yuko; Ariyoshi, Koichi; Tomii, Keisuke; Katakami, Nobuyuki

2018-06-01

Immune checkpoint inhibitors (ICIs) have demonstrated efficacy against various types of cancers. In addition to immune-related adverse events (irAEs) induced by ICIs, exacerbation of baseline autoimmune disease has been occasionally reported. This is the first report of autoimmune hemolytic anemia (AIHA) exacerbated by pembrolizumab. An 82-year-old Japanese male was diagnosed with lung adenocarcinoma 2 years ago. The patient had chronic anemia with positive direct and indirect Coombs test prior to initiating pembrolizumab therapy at a nearby hospital. However, a definitive diagnosis of AIHA was not made at that time. Seventeen days after the first dose of pembrolizumab, the patient was admitted to the Kobe City Medical Center General Hospital with severe hemolytic anemia (Hb 3.6 g/dL). After thorough examinations including bone marrow biopsy, the patient was diagnosed with pre-existing AIHA exacerbated by pembrolizumab therapy. Two weeks after treatment with prednisone, the levels of hemoglobin became stable with the reduced frequency of blood transfusion and improvements of hemolytic findings on blood tests and the patient was discharged from the hospital. This case report highlighted the importance of determining the patient's pre-existing autoimmune status associated with chronic anemia prior to initiating treatment with ICIs.

Hypophosphatemia and hemolytic anemia associated with diabetes mellitus and hepatic lipidosis in cats.

PubMed

Adams, L G; Hardy, R M; Weiss, D J; Bartges, J W

1993-01-01

Hypophosphatemia associated with hemolytic anemia was diagnosed in five cats with diabetes mellitus and in one cat with idiopathic hepatic lipidosis. The hematocrit began decreasing within 24 to 48 hours after documented hypophosphatemia in each case. The anemia resolved in all five surviving cats. Because of the temporal relationship and lack of other detectable causes, hemolytic anemia was presumed to be caused by hypophosphatemia. There were increased Heinz bodies in three of six hypophosphatemic cats during episodes of hemolysis. Intravenous potassium phosphate administration corrected the hypophosphatemia in four of five cats. The effective dosages of intravenous phosphate ranged from 0.011 to 0.017 mmol of phosphate/kg/h for 6 to 12 hours. Hypocalcemia (5.4 to 8.7 mg/dL) occurred in four of five cats treated with intravenous phosphate; however, only one cat developed clinical signs attributable to hypocalcemia. Based on this retrospective study, we recommend monitoring serum phosphorus concentration every 6 to 12 hours in cats likely to become hypophosphatemic. Treatment of hypophosphatemia in cats is warranted because of the apparent increased susceptibility of cats to hypophosphatemia-induced hemolysis. Cats with severe hypophosphatemia (< or = 1.5 mg/dL) should be given oral or parenteral phosphate if contraindications do not exist.

[Historical stages of Hemolytic Uremic Syndrome in Argentina (1964-2009)].

PubMed

Belardo, Marcela

2012-10-01

The aim is to present an historical time frame of Hemolytic Uremic Syndrome (HUS) in Argentina. From a public policy approach, the history of the disease is analyzed as an object of health policy and seeks to contribute in understanding the multiple dimensions of illness. As a medical and scientific issue, as a social problem and a matter of health policy, the article describes three phases ranging from its discovery up to the national program of HUS adopted in 2009. This article aims to provide an overview of developments in biomedical knowledge and the emergence of the issue in both social and political problem.

Hemolytic anemia after ingestion of the natural hair dye Lawsonia inermis (henna) in a dog.

PubMed

Jardes, Daniel J; Ross, Linda A; Markovich, Jessica E

2013-01-01

To describe the clinical presentation and case management of a dog that developed hemolytic anemia and evidence of renal tubular dysfunction after ingestion of a natural hair dye containing Lawsonia inermis (henna). To review cases of henna toxicity reported in the human literature. An 8-year-old female spayed Border Collie was presented 5 days after ingestion of a box of natural hair dye. The dog was showing signs of lethargy, vomiting, diarrhea, and weakness. A serum biochemistry profile, complete blood count, and urinalysis demonstrated evidence of renal tubular dysfunction and a regenerative anemia without spherocytosis. The dog was treated with a transfusion of packed RBCs and IV fluids, resulting in significant clinical improvement. Repeat diagnostics showed resolution of the anemia and no lasting evidence of tubular dysfunction. To the authors' knowledge, this is the first reported case in the veterinary literature of toxicity following ingestion of Lawsonia inermis (henna). Henna ingestion was associated with the development of hemolytic anemia and acute kidney injury. © Veterinary Emergency and Critical Care Society 2013.

Protein-Based Multifunctional Nanocarriers for Imaging, Photothermal Therapy, and Anticancer Drug Delivery.

PubMed

Pan, Uday Narayan; Khandelia, Rumi; Sanpui, Pallab; Das, Subhojit; Paul, Anumita; Chattopadhyay, Arun

2017-06-14

We report a simple approach for fabricating plasmonic and magneto-luminescent multifunctional nanocarriers (MFNCs) by assembling gold nanorods, iron oxide nanoparticles, and gold nanoclusters within BSA nanoparticles. The MFNCs showed self-tracking capability through single- and two-photon imaging, and the potential for magnetic targeting in vitro. Appreciable T 2 -relaxivity exhibited by the MFNCs indicated favorable conditions for magnetic resonance imaging. In addition to successful plasmonic-photothermal therapy of cancer cells (HeLa) in vitro, the MFNCs demonstrated efficient loading and delivery of doxorubicin to HeLa cells leading to significant cell death. The present MFNCs with their multimodal imaging and therapeutic capabilities could be eminent candidates for cancer theranostics.

Beta-Hemolytic, Multi-Lancefield Antigen-Agglutinating Enterococcus durans from a Pregnant Woman, Mimicking Streptococcus agalactiae

PubMed Central

Franco, Alessia; Gherardi, Giovanni; Marrollo, Roberta; Argentieri, Angela Valentina; Pimentel de Araujo, Fernanda; Amoruso, Roberta; Battisti, Antonio; Fazii, Paolo; Carretto, Edoardo

2014-01-01

A beta-hemolytic Lancefield antigen A-, B-, C-, D-, F-, and G-positive Enterococcus durans strain was cultivated from the rectovaginal swab of a pregnant woman who underwent antenatal screening for Streptococcus agalactiae. The isolate raised concern as to what extent similar strains are misrecognized and lead to false diagnosis of group B streptococci. PMID:24671782

Intervention effects of five cations and their correction on hemolytic activity of tentacle extract from the jellyfish Cyanea capillata

PubMed Central

2017-01-01

Cations have generally been reported to prevent jellyfish venom-induced hemolysis through multiple mechanisms by spectrophotometry. Little attention has been paid to the potential interaction between cations and hemoglobin, potentially influencing the antagonistic effect of cations. Here, we explored the effects of five reported cations, La3+, Mn2+, Zn2+, Cu2+ and Fe2+, on a hemolytic test system and the absorbance of hemoglobin, which was further used to measure their effects on the hemolysis of tentacle extract (TE) from the jellyfish Cyanea capillata. All the cations displayed significant dose-dependent inhibitory effects on TE-induced hemolysis with various dissociation equilibrium constant (Kd) values as follows: La3+ 1.5 mM, Mn2+ 93.2 mM, Zn2+ 38.6 mM, Cu2+ 71.9 μM and Fe2+ 32.8 mM. The transparent non-selective pore blocker La3+ did not affect the absorbance of hemoglobin, while Mn2+ reduced it slightly. Other cations, including Zn2+, Cu2+ and Fe2+, greatly decreased the absorbance with Kd values of 35.9, 77.5 and 17.6 mM, respectively. After correction, the inhibitory Kd values were 1.4 mM, 45.8 mM, 128.5 μM and 53.1 mM for La3+, Zn2+, Cu2+ and Fe2+, respectively. Mn2+ did not inhibit TE-induced hemolysis. Moreover, the inhibitory extent at the maximal given dose of all cations except La3+ was also diminished. These corrected results from spectrophotometry were further confirmed by direct erythrocyte counting under microscopy. Our results indicate that the cations, except for La3+, can interfere with the absorbance of hemoglobin, which should be corrected when their inhibitory effects on hemolysis by jellyfish venoms are examined. The variation in the inhibitory effects of cations suggests that the hemolysis by jellyfish venom is mainly attributed to the formation of non-selective cation pore complexes over other potential mechanisms, such as phospholipases A2 (PLA2), polypeptides, protease and oxidation. Blocking the pore-forming complexes may be a

Contribution to the food products' analysis: A research and evaluation on the hemolytic effect of some pesticides used in Lebanon.

PubMed

Al-Alam, Josephine; Millet, Maurice; Chbani, Asma; Fajloun, Ziad

2015-01-01

Pesticides are a real concern for the society as their use has become critical, leading sometimes to their accumulation as residues in fruits and vegetables. After examining the pesticides sold in Northern Lebanon, this study is focused on the analysis and identification of pesticides residues in fruits and vegetables that are harvested in this region and treated with the locally sold pesticides. Results show: first, (i) a use of Zineb by the name of another pesticide Micronized Sulfur to avoid prosecution; (ii) a significant presence of Metalaxyl in lemons and oranges; (iii) a significant presence of Trifluralin in strawberries; and (iv) a significant presence of Zineb in lemons and tomatoes. Second, with the use of hemolytic tests on human blood results show: (i) a critical concentration and a significant hemolytic effect of some pesticides used in Lebanon; and (ii) an absence of hemolytic effect in the collected fractions of the different analyzed fruit extracts containing pesticides. Finally, this work is the first step for pesticides' analysis in vegetables and fruits in Lebanon, initiating a wider analytical study in order to control and examine the use of pesticides which, according to our results, could have an adverse effect on human health over a long term.

Serum Shiga toxin 2 values in patients during the acute phase of post-diarrheal hemolytic uremic syndrome

USDA-ARS?s Scientific Manuscript database

Shiga toxins (Stxs) produced by Shiga toxin-producing Escherichia coli (STEC) are considered as the main causative agent, leading to the development of the hemolytic uremic syndrome (HUS); these toxins injure endothelial cells mainly the glomeruli. After passing through the intestinal wall, Stxs hav...

Preparation and antibacterial activity of compound chitosan-compound Yizhihao-nanoparticles.

PubMed

Ou, Sheng; Zhang, Yang-de

2008-05-01

To prepare chitosan (CS)-compound Yizhihao-nanoparticles (NP) and to investigate its antibacterial activity. CS NPs were formed by the incorporation of CS and Na3 PO4. CS-compound Yizhihao NPs were prepared by ion-cross-linking. The particle sizes and surface charges of CS NPs were determined by Malvern Zetasizer 1000-HAS and atomic force microscope (AFM), respectively. The antibacterial activity of CS-compound Yizhihao-NPs was studied in vitro and compared with that of compound Yizhihao powder. Malvern Zetasizer 1000-HAS and AFM demonstrated that the diameter of CS-compound Yizhihao NPs was (137.00+/-14.28)nm and CS NPs had (16.90+/-1.32)mV positive surface charges. The minimal inhibitory concentrations (MIC) of CS-compound Yizhihao NPs on Staphylococcus aureus,Pneumococcus,beta-hemolytic streptococcus, and Escherichia coli were 1:32,1:32,1:16,and 1:2, respectively. The minimal bactericidal concentrations (MBC) of CS-compound Yizhihao-NPs on Staphylococcus aureus, Pneumococcus, beta-hemolytic streptococcus, and Escherichia coli were 1:16,1:16,1:8, and 1:2, respectively. The antibacterial efficacy of CS-compound Yizhihao-NPs to Staphylococcus aureus, Pneumococcus, and beta-hemolytic streptococcus had been improved significantly (P< 0.05). CS-compound Yizhihao-nanoparticles have obvious antibacterial activity to the Staphylococcus aureus,Pneumococcus,and beta-hemolytic streptococcus,which lays the experimental foundation for new preparation of traditional Chinese medicine in future research.

[Etiologies of non-hemolytic jaundice in infants: a retrospective analysis of 3113 cases].

PubMed

Peng, Xiaorong; Xu, Hongmei

2015-06-01

To investigate the causes of non-hemolytic jaundice among infants in Chongqing, China from the period of 1982 to 2011 and to determine whether the etiologies have changed over the past 30 years. The medical records of 3 113 infants,aged 1 month to 1 year,admitted to our hospital with non-hemolytic jaundice were collected and stratified according to decade-long time periods: group A (1982-1991), n=537; group B (1992-2001), n=786; group C (2002-2011), n=1 790. Data on sex, age, etiology and bilirubin level were retrospectively assessed using the chi-square test. In the three groups, boys consistently accounted for the majority of cases (group A:74.3%, group B:66.7%, group C:62.6%). In group A, 52% of the patients were 1-2 months of age; the peak age of patients in both group B and C was 2-3 months (group B:67.8%, group C:61.0%). Group A showed the highest level of patients with mildly elevated total bilirubin level (80.3%); however, moderately elevated total bilirubin level was most frequent in group B (53.4%) and group C (49.7%). The main etiologic diagnoses of the patients in group A were cytomegalovirus (CMV) infection (31.7%), sepsis (18.2%), hepatitis B virus (HBV) (1.3%), and biliary tract anomalies (1.3%); 46.6% of the cases had unclear cause. The main etiologic diagnoses of the cases in group B were CMV infection (36.0%), sepsis (21.5%), breast milk jaundice (2.0%), and HBV (1.9%); 37.9% of the cases had unclear cause. The main etiologic diagnoses of the cases in group C were CMV infection (42.6%), sepsis (7.5%), breast milk jaundice (17.7%), and biliary tract anomalies (2.46%); 29.1% of the cases had unclear cause. In Chongqing, infective factors, especially CMV, remain the main cause of nonhemolytic jaundice in infants, but bacterial etiologies have declined over the past 30 years.Non-infective factors, such as biliary tract anomalies and inherited metabolic diseases, have trended upwards. Although there has been great progress in the clinical management of

Nanocarriers as phototherapeutic drug delivery system: Appraisal of three different nanosystems in an in vivo and in vitro exploratory study.

PubMed

Ricci-Junior, Eduardo; de Oliveira de Siqueira, Luciana Betzler; Rodrigues, Raphaela Aparecida Schuenck; Sancenón, Félix; Martínez-Máñez, Ramón; de Moraes, João Alfredo; Santos-Oliveira, Ralph

2018-03-01

The use of nanosystems as diagnosing and therapy systems is increasing each year. There are several nanosystems available and the most prominent ones are: mesoporous silica, nanoemulsion and polymeric nanoparticles. With characteristics like low toxicology, and easy-producing process they have advantages when compared with the traditional system used, as they show specific targeting, controlled release, and higher penetration. In this study we tested three different nanocarriers (polymeric nanoparticles, nanoemulsion and mesoporous silica) containing phthalocyanineas possible PDT drugs (nanodrugs). They were tested in vitro and in vivo: cells and healthy mice, respectively, in order to understand the biological behavior and reach the initial conclusions. The results in cells showed that a dose response was observed with different concentrations of the three nanocarriers. The results in animal showed that all nanosystems have potential for application in PDT, since they were able to produce a visible effect in healthy animals. Copyright © 2017 Elsevier B.V. All rights reserved.

Prevention of garlic-induced hemolytic anemia using some tropical green leafy vegetables.

PubMed

Oboh, Ganiyu

2004-01-01

Garlic (Allium sativum) is popularly consumed in Nigeria because of its health benefit in treatment and management of several disease conditions. However, excessive intake of garlic may cause hemolytic anemia. This project sought to investigate the ability of some commonly consumed tropical green leafy vegetables-namely, Amaranthus cruentus, Baselia alba, Solanum macrocarpon, Ocimum gratissimum, and Corchorus olitorius-to prevent garlic-induced hemolytic anemia. Wister strain albino rats were fed diet containing 4% garlic with or without 40% vegetable supplement. The study showed that there was a decrease in daily feed intake (6.7-7.2 g/rat/day), daily weight gain (0.7-1.5 g/rat/day), and digestibility (70.4-91.5%) of rats fed diet with garlic (4%), with or without vegetable (40%) supplement, compared with those rats fed the basal diet without garlic (4%) and vegetable (40%) supplement (digestibility, 95.5%; daily feed intake, 7.5 g/rat/day; and daily weight gain, 2.0 g/rat/day). However, there was a significant decrease (P < .05) in the packed cell volume (PCV) (31.0%), hemoglobin (Hb) (10.2 g/dL), red blood cells (RBCs) (4.3 x 10(6)/microL), and white blood cells (WBCs) (3.5 x 10(6)/microL) of rats fed diet with garlic (4%) but without vegetable compared with those rats fed diet without garlic (4%) and vegetable (40%) supplements (PCV, 38.2%; Hb, 13.0 g/dL; RBCs, 5.5 x 10(6)/microL; and WBCs, 4.0 x 10(6)/microL). Conversely, there was a significant increase in the PCV (33.5-35.6%), Hb (12.0-12.5 g/dL), and RBCs (4.9-5.3 x 10(6)/microL) of rats fed diet with garlic (4%) and vegetable (40%) supplement compared with rats fed diet with 4% garlic supplement (except S. macrocarpon and C. olitorius). Furthermore, there was a significant decrease (P < .05) in mean corpuscular volume (69.2-72.0 fL) of rats fed the basal and those fed diet with garlic and vegetable (except C. olitorus and S. macrocarpon) supplement compared with the rats fed diet with garlic but without

Designed Synthesis of Nanostructured Magnetic Hydroxyapatite Based Drug Nanocarrier for Anti-Cancer Drug Delivery toward the Treatment of Human Epidermoid Carcinoma

PubMed Central

Govindan, Bharath; Swarna Latha, Beeseti; Nagamony, Ponpandian; Ahmed, Faheem; Saifi, Muheet Alam; Harrath, Abdel Halim; Alwasel, Saleh; Mansour, Lamjed; Alsharaeh, Edreese H.

2017-01-01

Superparamagnetic Fe3O4 nanoparticles on hydroxyapatite nanorod based nanostructures (Fe3O4/HAp) were synthesized using hydrothermal techniques at 180 °C for 12 h and were used as drug delivery nanocarriers for cancer cell therapeutic applications. The synthesized Fe3O4/HAp nanocomposites were characterized by X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET)-analysis, and vibrating sample magnetometry (VSM). The morphologies of the Fe3O4/HAp nanocomposites show 15 nm Fe3O4 nanoparticles dispersed in the form of rods. The BET result shows that the synthesized samples have a high specific surface area of 80 m2 g−1 with mesoporous structures. Magnetic measurements revealed that the sample has high saturation magnetization of 18 emu/g with low coercivity. The Fe3O4/HAp nanocomposites had a large specific surface area (SSA), high mesoporous volume, and good magnetic property, which made it a suitable nanocarrier for targeted drug delivery systems. The chemotherapeutic agent, andrographolide, was used to investigate the drug delivery behavior of the Fe3O4/HAp nanocomposites. The human epidermoid skin cancer cells (A431) were used as the model targeting cell lines by treating with andrographolide loaded Fe3O4/HAp nanosystems and were further evaluated for their antiproliferative activities and the induction of apoptosis. Also, the present nanocomposite shows better biocompatibility, therefore it can be used as suitable drug vehicle for cancer therapy applications. PMID:28587317

STUDIES ON NON-HEMOLYTIC STREPTOCOCCI ISOLATED FROM THE RESPIRATORY TRACT OF MAN

PubMed Central

Horsfall, Frank L.

1951-01-01

The type specific immunological properties of certain non-hemolytic streptococci, including Str. salivarius type I and type II, present in the respiratory tract of human beings appear to be dependent upon the presence of capsular polysaccharides. The levans formed from sucrose by Str. salivarius (encapsulated S cells or non-encapsulated R variants), or by cell-free enzymes derived from these microorganisms, are indistinguishable immunologically and show no evidence of type specificity. Such levans appear to be immunologically distinct from and unrelated to the capsular polysaccharides of the microorganisms which produce them. PMID:14824398

Covalent and non-covalent curcumin loading in acid-responsive polymeric micellar nanocarriers

NASA Astrophysics Data System (ADS)

Gao, Min; Chen, Chao; Fan, Aiping; Zhang, Ju; Kong, Deling; Wang, Zheng; Zhao, Yanjun

2015-07-01

Poor aqueous solubility, potential degradation, rapid metabolism and elimination lead to low bioavailability of pleiotropic impotent curcumin. Herein, we report two types of acid-responsive polymeric micelles where curcumin was encapsulated via both covalent and non-covalent modes for enhanced loading capacity and on-demand release. Biodegradable methoxy poly(ethylene glycol)-poly(lactic acid) copolymer (mPEG-PLA) was conjugated with curcumin via a hydrazone linker, generating two conjugates differing in architecture (single-tail versus double-tail) and free curcumin was encapsulated therein. The two micelles exhibited similar hydrodynamic size at 95 ± 3 nm (single-tail) and 96 ± 3 nm (double-tail), but their loading capacities differed significantly at 15.0 ± 0.5% (w/w) (single-tail) and 4.8 ± 0.5% (w/w) (double-tail). Under acidic sink conditions (pH 5.0 and 6.0), curcumin displayed a faster release from the single-tail nanocarrier, which was correlated to a low IC50 of 14.7 ± 1.6 (μg mL-1) compared to the value of double-tail micelle (24.9 ± 1.3 μg mL-1) in HeLa cells. The confocal imaging and flow cytometry analysis demonstrated a superior capability of single-tail micelle for intracellular curcumin delivery, which was a consequence of the higher loading capacity and lower degree of mPEG surface coverage. In conclusion, the dual loading mode is an effective means to increase the drug content in the micellar nanocarriers whose delivery efficiency is highly dependent on its polymer-drug conjugate architecture. This strategy offers an alternative nanoplatform for intracellularly delivering impotent hydrophobic agents (i.e. curcumin) in an efficient stimuli-triggered way, which is valuable for the enhancement of curcumin’s efficacy in managing a diverse range of disorders.

NIR-induced spatiotemporally controlled gene silencing by upconversion nanoparticle-based siRNA nanocarrier.

PubMed

Chen, Guojun; Ma, Ben; Xie, Ruosen; Wang, Yuyuan; Dou, Kefeng; Gong, Shaoqin

2017-12-27

Spatiotemporal control over the release or activation of biomacromolecules such as siRNA remains a significant challenge. Light-controlled release has gained popularity in recent years; however, a major limitation is that most photoactivable compounds/systems respond only to UV irradiation, but not near-infrared (NIR) light that offers a deeper tissue penetration depth and better biocompatibility. This paper reports a simple NIR-to-UV upconversion nanoparticle (UCNP)-based siRNA nanocarrier for NIR-controlled gene silencing. siRNA is complexed onto a NaYF 4 :Yb/Tm/Er UCNP through an azobenzene (Azo)-cyclodextrin (CD) host-guest interaction. The UV emission generated by the NIR-activated UCNP effectively triggers the trans-to-cis photoisomerization of azobenzene, thus leading to the release of siRNA due to unmatched host-guest pairs. The UCNP-siRNA complexes are also functionalized with PEG (i.e., UCNP-(CD/Azo)-siRNA/PEG NPs), targeting ligands (i.e., EGFR-specific GE11 peptide), acid-activatable cell-penetrating peptides (i.e., TH peptide), and imaging probes (i.e., Cy5 fluorophore). The UCNP-(CD/Azo)-siRNA/PEG NPs with both GE11 and TH peptides display a high level of cellular uptake and an excellent endosomal/lysosomal escape capability. More importantly, NIR-controlled spatiotemporal knockdown of GFP expression is successfully achieved in both a 2D monolayer cell model and a 3D multicellular tumor spheroid model. Thus, this simple and versatile nanoplatform has great potential for the selective activation or release of various biomacromolecules. Copyright © 2017. Published by Elsevier B.V.

The Hemolytic Enterotoxin HBL Is Broadly Distributed among Species of the Bacillus cereus Group

PubMed Central

Prüß, Birgit M.; Dietrich, Richard; Nibler, Birgit; Märtlbauer, Erwin; Scherer, Siegfried

1999-01-01

The prevalence of the hemolytic enterotoxin complex HBL was determined in all species of the Bacillus cereus group with the exception of Bacillus anthracis. hblA, encoding the binding subunit B, was detected by PCR and Southern analysis and was confirmed by partial sequencing of 18 strains. The sequences formed two clusters, one including B. cereus and Bacillus thuringiensis strains and the other one consisting of Bacillus mycoides, Bacillus pseudomycoides, and Bacillus weihenstephanensis strains. From eight B. thuringiensis strains, the enterotoxin gene hblA could be amplified. Seven of them also expressed the complete HBL complex as determined with specific antibodies against the L1, L2, and B components. Eleven of 16 B. mycoides strains, all 3 B. pseudomyoides strains, 9 of 15 B. weihenstephanensis strains, and 10 of 23 B. cereus strains carried hblA. While HBL was not expressed in the B. pseudomycoides strains, the molecular assays were in accordance with the immunological assays for the majority of the remaining strains. In summary, the hemolytic enterotoxin HBL seems to be broadly distributed among strains of the B. cereus group and relates neither to a certain species nor to a specific environment. The consequences of this finding for food safety considerations need to be evaluated. PMID:10584001

Hemolytic disease in the newborn - history and prevention in the world and the Czech Republic.

PubMed

Santavy, Jiri

2010-06-01

Hemolytic disease in the newborn with its typical signs and poor prognosis has been known for centuries. Historically it can be divided into three pathological states which are fetal hydrops (hydrops fetus universalis), neonatal jaundice (icterus neonati gravis familiaris) and fetal anemia (anemia neonati). Almost 70 reports with quite accurate descriptions were found up to the end of 19th century. The patho physiological basis of the condition began to be studied at the beginning of the last century and the development of our knowledge is an example of the cooperation between pathologists, pediatricians, hematologists and later, obstetricians, immunologists and geneticists. Despite all the advances in this field it remains a serious disease up to this time. It is not managed successfully in all cases and despite successful immunological prophylaxis there are cases when we need to administer intrauterine transfusion based on the information received by dopplerometric measurement of arteria cerebri perfusion and fetal blood sampling. Review of lover cited literature. The history of the hemolytic disease in the newborn, its condition and approaches to it has not been recently compiled in the Czech Republic.

Nanocarrier-based hydrogel of betamethasone dipropionate and salicylic acid for treatment of psoriasis

PubMed Central

Baboota, Sanjula; Alam, Md Sarfaraz; Sharma, Shrestha; Sahni, Jasjeet K; Kumar, Anil; Ali, Javed

2011-01-01

Introduction: Betamethasone dipropionate (BD) has anti-inflammatory, immunomodulatory, and antiproliferative activity. The aim of the current work was to test the hypothesis that the addition of corticosteroid such as BD and a keratolytic agent such as salicylic acid in nanocarrier based microemulsions formulation would result in enhancement and sustaining of corticosteroid delivery rate leading to better anti-psoriatic activity. Clinical use of BD is restricted to some extent due to its poor permeability across the skin. So to increase its permeation across the skin, microemulsion-based gel formulations were prepared and characterised. Materials and Methods: Microemulsions were prepared by aqueous phase titration method, using oleic acid:sefsol (1.5:1), Tween 20, isopropyl alcohol, and distilled water as the oil phase, surfactant, cosurfactant and aqueous phase, respectively. Selected formulations were subjected to physical stability studies and consequently in vitro skin permeation studies. Surface studies of optimized formulation were done by transmission electron microscopy. In vivo anti-inflammatory activity was done by carageenan-induced raw paw edema method. Results: The droplet size of microemulsions ranged from 60 to 190 nm. The optimized formulation exhibited viscosity 28.55 ± 2.03 mP, refractive index 1.409, pH 6.4, and conductivity 10-4 scm-1. The optimized microemulsion was converted into hydrogel using carbopol 934, and salicylic acid was incorporated into it. Drug deposition in skin was found to be 29.73 μg/mg. Assessment of skin permeation was done by histopathology studies which indicated changes in the structure of epidermal membrane of skin. In vivo anti-inflammatory activity indicated 72.11% and 43.96% inhibition of inflammation in case of developed microemulsion gel and marketed gel, respectively. Conclusions: The developed microemulsion gel containing BD and salicylic acid provided sustained and good anti-inflammatory activity for the

Factor H autoantibody is associated with atypical hemolytic uremic syndrome in children in the United Kingdom and Ireland.

PubMed

Brocklebank, Vicky; Johnson, Sally; Sheerin, Thomas P; Marks, Stephen D; Gilbert, Rodney D; Tyerman, Kay; Kinoshita, Meredith; Awan, Atif; Kaur, Amrit; Webb, Nicholas; Hegde, Shivaram; Finlay, Eric; Fitzpatrick, Maggie; Walsh, Patrick R; Wong, Edwin K S; Booth, Caroline; Kerecuk, Larissa; Salama, Alan D; Almond, Mike; Inward, Carol; Goodship, Timothy H; Sheerin, Neil S; Marchbank, Kevin J; Kavanagh, David

2017-11-01

Factor H autoantibodies can impair complement regulation, resulting in atypical hemolytic uremic syndrome, predominantly in childhood. There are no trials investigating treatment, and clinical practice is only informed by retrospective cohort analysis. Here we examined 175 children presenting with atypical hemolytic uremic syndrome in the United Kingdom and Ireland for factor H autoantibodies that included 17 children with titers above the international standard. Of the 17, seven had a concomitant rare genetic variant in a gene encoding a complement pathway component or regulator. Two children received supportive treatment; both developed established renal failure. Plasma exchange was associated with a poor rate of renal recovery in seven of 11 treated. Six patients treated with eculizumab recovered renal function. Contrary to global practice, immunosuppressive therapy to prevent relapse in plasma exchange-treated patients was not adopted due to concerns over treatment-associated complications. Without immunosuppression, the relapse rate was high (five of seven). However, reintroduction of treatment resulted in recovery of renal function. All patients treated with eculizumab achieved sustained remission. Five patients received renal transplants without specific factor H autoantibody-targeted treatment with recurrence in one who also had a functionally significant CFI mutation. Thus, our current practice is to initiate eculizumab therapy for treatment of factor H autoantibody-mediated atypical hemolytic uremic syndrome rather than plasma exchange with or without immunosuppression. Based on this retrospective analysis we see no suggestion of inferior treatment, albeit the strength of our conclusions is limited by the small sample size. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Genetics of hemolytic uremic syndromes.

PubMed

Malina, Michal; Roumenina, Lubka T; Seeman, Tomáš; Le Quintrec, Moglie; Dragon-Durey, Marie-Agnes; Schaefer, Franz; Fremeaux-Bacchi, Véronique

2012-03-01

Hemolytic uremic syndrome (HUS) is a very rare disease (two cases per year per 1 million population) but represents the most common cause of acute renal failure in young children that require dialysis. The majority of cases in childhood (90%) is caused by Shiga toxin producing Escherichia coli infection. This typical form of the disease does not relapse and has a good prognosis if the acute status can be managed successfully. Atypical HUS (aHUS) is a severe and frequently relapsing disorder with the same triad of thrombocytopenia, hemolysis and acute renal failure in the absence of Shiga toxin E. coli infection. More than 50% of patients with atypical HUS progress to chronic renal dysfunction and 10% die due to complications of the disease. Atypical HUS appears to have a genetic basis. Mutations in genes coding for components of the alternative complement pathway are found in about 60% of cases. The clinical presentation of aHUS overlaps with that of other thrombotic microangiopathies, rendering the diagnosis on clinical grounds alone extremely difficult. In recent years, genetic testing has opened the way for molecular diagnostics and helped establishing therapeutically and prognostically useful genotype-phenotype correlations. This review summarizes recent findings regarding the genetic basis of the HUS. The pathophysiology of the disease and the implication of genetic abnormalities in the complement system for the different types of HUS are discussed. Copyright © 2012. Published by Elsevier Masson SAS.

Coinfection of hepatitis A virus genotype IA and IIIA complicated with autoimmune hemolytic anemia, prolonged cholestasis, and false-positive immunoglobulin M anti-hepatitis E virus: a case report.

PubMed

Kim, Hee Sup; Jeong, Sook Hyang; Jang, Je Hyuck; Myung, Hyung Joon; Kim, Jin Wook; Bang, Soo Mee; Song, Sang Hoon; Kim, Haeryoung; Yun, Hae Sun

2011-12-01

A 37-year-old male presented with fever and jaundice was diagnosed as hepatitis A complicated with progressive cholestasis and severe autoimmune hemolytic anemia. He was treated with high-dose prednisolone (1.5 mg/kg), and eventually recovered. His initial serum contained genotype IA hepatitis A virus (HAV), which was subsequently replaced by genotype IIIA HAV. Moreover, at the time of development of hemolytic anemia, he became positive for immunoglobulin M (IgM) anti-hepatitis E virus (HEV). We detected HAV antigens in the liver biopsy specimen, while we detected neither HEV antigen in the liver nor HEV RNA in his serum. This is the first report of hepatitis A coinfected with two different genotypes manifesting with autoimmune hemolytic anemia, prolonged cholestasis, and false-positive IgM anti-HEV.

Coinfection of hepatitis A virus genotype IA and IIIA complicated with autoimmune hemolytic anemia, prolonged cholestasis, and false-positive immunoglobulin M anti-hepatitis E virus: a case report

PubMed Central

Kim, Hee-Sup; Jang, Je-Hyuck; Myung, Hyung-Joon; Kim, Jin-Wook; Bang, Soo-Mee; Song, Sang Hoon; Kim, Haeryoung; Yun, Hae Sun

2011-01-01

A 37-year-old male presented with fever and jaundice was diagnosed as hepatitis A complicated with progressive cholestasis and severe autoimmune hemolytic anemia. He was treated with high-dose prednisolone (1.5 mg/kg), and eventually recovered. His initial serum contained genotype IA hepatitis A virus (HAV), which was subsequently replaced by genotype IIIA HAV. Moreover, at the time of development of hemolytic anemia, he became positive for immunoglobulin M (IgM) anti-hepatitis E virus (HEV). We detected HAV antigens in the liver biopsy specimen, while we detected neither HEV antigen in the liver nor HEV RNA in his serum. This is the first report of hepatitis A coinfected with two different genotypes manifesting with autoimmune hemolytic anemia, prolonged cholestasis, and false-positive IgM anti-HEV. PMID:22310798

Development of a novel probe sonication assisted enhanced loading of 5-FU in SPION encapsulated pectin nanocarriers for magnetic targeted drug delivery system.

PubMed

Dutta, Raj Kumar; Sahu, Saurabh

2012-09-01

A novel probe sonication method is developed to enhance loading of 5-fluorouracil (5-FU) in SPION encalsulated pectin nanocarriers of 100-150 nm size (referred here as MP-5FU nanocarriers). Probe sonication at 20 kHz for 60 min resulted in 5-FU loading efficiency of 33.2 ± 2.5%w/w and corresponding drug loading content of 18.2 ± 1.1 wt%. These are two folds higher than literature report of 5-FU loading in pectin. The enhanced loading is attributed to increase in the rate of dissolution of 5-FU in pectin due to transmission of kHz order sonic waves which increases temperature and pressure in the medium due to formation and collapsing of cavitation bubbles. The fabricated MP-5FU nanocarriers with saturation magnetization (43.13 emu/g) exhibited pH responsive, swelling controlled in vitro release of 5-FU in simulated gastric fluid at pH 1.2, in simulated intestinal fluid at pH 6.8, in simulated colonic fluid at pH 5.5, and in phosphate buffer solution at pH 7.4. The cytotoxicity of MP-5FU was measured by sulforhodamine B (SRB) assay and its GI(50) was more than 5mg/mL for cancer cells of HT-29 (colon) and Hep G2 (liver), while it was 3.7 mg/mL for cancer cells of MIA-PaCa-2 (Pancreas). Copyright © 2012 Elsevier B.V. All rights reserved.

Molecular Basis for Group B β -hemolytic Streptococcal Disease

NASA Astrophysics Data System (ADS)

Hellerqvist, Carl G.; Sundell, Hakan; Gettins, Peter

1987-01-01

Group B β -hemolytic Streptococcus (GBS) is a major pathogen affecting newborns. We have investigated the molecular mechanism underlying the respiratory distress induced in sheep after intravenous injection of a toxin produced by this organism. The pathophysiological response is characterized by pulmonary hypertension, followed by granulocytopenia and increased pulmonary vascular permeability to protein. 31P NMR studies of GBS toxin and model components before and after reductive alkaline hydrolysis demonstrated that phosphodiester residues are an integral part of the GBS toxin. Reductive alkaline treatment cleaves phosphate esters from secondary and primary alcohols and renders GBS toxin nontoxic in the sheep model and inactive as a mediator of elastase release in vitro from isolated human granulocytes. We propose that the interaction of cellular receptors with mannosyl phosphodiester groups plays an essential role in the pathophysiological response to GBS toxin.

Investigation of cutaneous penetration properties of stearic acid loaded to dendritic core-multi-shell (CMS) nanocarriers.

PubMed

Lohan, S B; Icken, N; Teutloff, C; Saeidpour, S; Bittl, R; Lademann, J; Fleige, E; Haag, R; Haag, S F; Meinke, M C

2016-03-30

Dendritic core-multi shell (CMS) particles are polymer based systems consisting of a dendritic polar polyglycerol polymer core surrounded by a two-layer shell of nonpolar C18 alkyl chains and hydrophilic polyethylene glycol. Belonging to nanotransport systems (NTS) they allow the transport and storage of molecules with different chemical characters. Their amphipihilic character CMS-NTS permits good solubility in aqueous and organic solutions. We showed by multifrequency electron paramagnetic resonance (EPR) spectroscopy that spin-labeled 5-doxyl stearic acid (5DSA) can be loaded into the CMS-NTS. Furthermore, the release of 5DSA from the carrier into the stratum corneum of porcine skin was monitored ex vivo by EPR spectroscopy. Additionally, the penetration of the CMS-NTS into the skin was analyzed by fluorescence microscopy using indocarbocyanine (ICC) covalently bound to the nanocarrier. Thereby, no transport into the viable skin was observed, whereas the CMS-NTS had penetrated into the hair follicles down to a depth of 340 μm ± 82 μm. Thus, it could be shown that the combined application of fluorescence microscopy and multi-frequency EPR spectroscopy can be an efficient tool for investigating the loading of spin labeled drugs to nanocarrier systems, drug release and penetration into the skin as well as the localization of the NTS in the skin. Copyright © 2016 Elsevier B.V. All rights reserved.

Self-Assembled Nanocarriers Based on Amphiphilic Natural Polymers for Anti- Cancer Drug Delivery Applications.

PubMed

Sabra, Sally; Abdelmoneem, Mona; Abdelwakil, Mahmoud; Mabrouk, Moustafa Taha; Anwar, Doaa; Mohamed, Rania; Khattab, Sherine; Bekhit, Adnan; Elkhodairy, Kadria; Freag, May; Elzoghby, Ahmed

2017-01-01

Micellization provides numerous merits for the delivery of water insoluble anti-cancer therapeutic agents including a nanosized 'core-shell' drug delivery system. Recently, hydrophobically-modified polysaccharides and proteins are attracting much attention as micelle forming polymers to entrap poorly soluble anti-cancer drugs. By virtue of their small size, the self-assembled micelles can passively target tumor tissues via enhanced permeation and retention effect (EPR). Moreover, the amphiphilic micelles can be exploited for active-targeted drug delivery by attaching specific targeting ligands to the outer micellar hydrophilic surface. Here, we review the conjugation techniques, drug loading methods, physicochemical characteristics of the most important amphiphilic polysaccharides and proteins used as anti-cancer drug delivery systems. Attention focuses on the mechanisms of tumor-targeting and enhanced anti-tumor efficacy of the encapsulated drugs. This review will highlight the remarkable advances of hydrophobized polysaccharide and protein micelles and their potential applications as anti-cancer drug delivery nanosystems. Micellar nanocarriers fabricated from amphiphilic natural polymers hold great promise as vehicles for anti-cancer drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Gold nanoflowers with mesoporous silica as "nanocarriers" for drug release and photothermal therapy in the treatment of oral cancer using near-infrared (NIR) laser light

NASA Astrophysics Data System (ADS)

Song, Wenzhi; Gong, Junxia; Wang, Yuqian; Zhang, Yan; Zhang, Hongmei; Zhang, Weihang; Zhang, Hu; Liu, Xin; Zhang, Tianfu; Yin, Wanzhong; Yang, Wensheng

2016-04-01

In this experiment, we successfully developed nanocarriers in the form of gold nanoflowers coated with two layers of silica for the purposes of drug loading and NIR (near-infrared) photothermal therapy for the treatment of oral cancer. The gold nanoflowers converted NIR laser energy into heat energy. The cores were coated with a thin silica layer (AuNFs@SiO2) to protect the gold nanoflowers from intraparticle ripening. The second layer was mesoporous silica (AuNFs@SiO2@mSiO2), which acted as a nanocarrier for anticancer drug (DOX) loads. The mean effective diameter of the nanoparticles was approximately 150-200 nm, whereas the peak absorption of the AuNFs was 684 nm. After the AuNFs were encapsulated by the silica shells, the plasmonic absorption peak of AuNFs@SiO2 and AuNFs@SiO2@mSiO2 exhibited a red shift to 718 nm. When exposed to an 808 nm NIR laser, these crystals showed an obvious photothermal conversion in the NIR region and a highly efficient release of DOX. Biocompatibility was assessed in vitro using Cell Counting Kit-8 assays, and the results showed that the nanocarriers induced no obvious cytotoxicity. This nanomaterial could be considered a new type of material that shows promising potential for photothermal-chemotherapy against malignant tumours, including those of oral cancers.

Acute hemolytic vascular inflammatory processes are prevented by nitric oxide replacement or a single dose of hydroxyurea.

PubMed

Almeida, Camila Bononi; Souza, Lucas Eduardo Botelho; Leonardo, Flavia Costa; Costa, Fabio Trindade Maranhão; Werneck, Claudio C; Covas, Dimas Tadeu; Costa, Fernando Ferreira; Conran, Nicola

2015-08-06

Hemolysis and consequent release of cell-free hemoglobin (CFHb) impair vascular nitric oxide (NO) bioavailability and cause oxidative and inflammatory processes. Hydroxyurea (HU), a common therapy for sickle cell disease (SCD), induces fetal Hb production and can act as an NO donor. We evaluated the acute inflammatory effects of intravenous water-induced hemolysis in C57BL/6 mice and determined the abilities of an NO donor, diethylamine NONOate (DEANO), and a single dose of HU to modulate this inflammation. Intravenous water induced acute hemolysis in C57BL/6 mice, attaining plasma Hb levels comparable to those observed in chimeric SCD mice. This hemolysis resulted in significant and rapid systemic inflammation and vascular leukocyte recruitment within 15 minutes, accompanied by NO metabolite generation. Administration of another potent NO scavenger (2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) to C57BL/6 mice induced similar alterations in leukocyte recruitment, whereas hemin-induced inflammation occurred over a longer time frame. Importantly, the acute inflammatory effects of water-induced hemolysis were abolished by the simultaneous administration of DEANO or HU, without altering CFHb, in an NO pathway-mediated manner. In vitro, HU partially reversed the Hb-mediated induction of endothelial proinflammatory cytokine secretion and adhesion molecule expression. In summary, pathophysiological levels of hemolysis trigger an immediate inflammatory response, possibly mediated by vascular NO consumption. HU presents beneficial anti-inflammatory effects by inhibiting rapid-onset hemolytic inflammation via an NO-dependent mechanism, independently of fetal Hb elevation. Data provide novel insights into mechanisms of hemolytic inflammation and further support perspectives for the use of HU as an acute treatment for SCD and other hemolytic disorders. © 2015 by The American Society of Hematology.

A case of pernicious anemia requiring differential diagnosis of autoimmune hemolytic anemia complication.

PubMed

Todo, Saki; Okamoto, Kohei; Sugimoto, Takeshi; Takahashi, Toshimasa; Nakagawa, Yasushi; Arai, Takashi; Nishiyama, Katsuhito; Hara, Kenta; Yasutomo, Yoshiro; Yokono, Koichi

2017-09-01

An 80-year-old female was admitted to our hospital due to malaise. The initial diagnosis on admission was pernicious anemia (PA), Hashimoto thyroiditis and autoimmune atrophic gastritis. Autoimmune hemolytic anemia was suspected because direct antiglobulin test (DAT) was positive. Treatment with vitamin B12 improved anemia, with the disappearance of hemolysis. In some cases, PA patients with positive DAT may have hemolysis without the involvement of the autoimmune mechanism. Therefore, it is important to carefully assess PA patients with hemolysis and positive DAT for the prevention of unnecessary administration of steroid therapy.

Nanocarrier mediated retinal drug delivery: overcoming ocular barriers to treat posterior eye diseases.

PubMed

Bisht, Rohit; Mandal, Abhirup; Jaiswal, Jagdish K; Rupenthal, Ilva D

2018-03-01

Effective drug delivery to the retina still remains a challenge due to ocular elimination mechanisms and complex barriers that selectively limit the entry of drugs into the eye. To overcome these barriers, frequent intravitreal injections are currently used to achieve high drug concentrations in vitreous and retina. However, these repetitive injections may result in several side effects. Recent advancements in the field of nanoparticle-based drug delivery could overcome some of these unmet needs and various preclinical studies conducted to date have demonstrated promising results of nanotherapies in the treatment of retinal diseases. Compared to the majority of commercially available ocular implants, the biodegradable nature of most nanoparticles (NPs) avoids the need for surgical implantation and removal after the release of the payload. In addition, the sustained drug release from NPs over an extended period of time reduces the need for frequent intravitreal injections and the risk of associated side effects. The nanometer size and highly modifiable surface properties make NPs excellent candidates for targeted ocular drug delivery. Studies have shown that nanocarriers enhance the intravitreal half-life and thus bioavailability of a number of drugs including proteins and peptides. In addition, they have shown promising results in delivering genetic material to the retinal tissues by protecting it from possible intravitreal degradation. This review covers the various challenges associated with drug delivery to the posterior segment of the eye, particularly the retina, and highlights the application of nanocarriers to overcome these challenges in context with recent advances in preclinical studies. WIREs Nanomed Nanobiotechnol 2018, 10:e1473. doi: 10.1002/wnan.1473 This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Implantable Materials and Surgical Technologies > Nanomaterials and Implants. © 2017 Wiley Periodicals

Complement Factor B Mutations in Atypical Hemolytic Uremic Syndrome—Disease-Relevant or Benign?

PubMed Central

Marinozzi, Maria Chiara; Vergoz, Laura; Rybkine, Tania; Ngo, Stephanie; Bettoni, Serena; Pashov, Anastas; Cayla, Mathieu; Tabarin, Fanny; Jablonski, Mathieu; Hue, Christophe; Smith, Richard J.; Noris, Marina; Halbwachs-Mecarelli, Lise; Donadelli, Roberta; Fremeaux-Bacchi, Veronique

2014-01-01

Atypical hemolytic uremic syndrome (aHUS) is a genetic ultrarare renal disease associated with overactivation of the alternative pathway of complement. Four gain-of-function mutations that form a hyperactive or deregulated C3 convertase have been identified in Factor B (FB) ligand binding sites. Here, we studied the functional consequences of 10 FB genetic changes recently identified from different aHUS cohorts. Using several tests for alternative C3 and C5 convertase formation and regulation, we identified two gain-of-function and potentially disease-relevant mutations that formed either an overactive convertase (M433I) or a convertase resistant to decay by FH (K298Q). One mutation (R178Q) produced a partially cleaved protein with no ligand binding or functional activity. Seven genetic changes led to near-normal or only slightly reduced ligand binding and functional activity compared with the most common polymorphism at position 7, R7. Notably, none of the algorithms used to predict the disease relevance of FB mutations agreed completely with the experimental data, suggesting that in silico approaches should be undertaken with caution. These data, combined with previously published results, suggest that 9 of 15 FB genetic changes identified in patients with aHUS are unrelated to disease pathogenesis. This study highlights that functional assessment of identified nucleotide changes in FB is mandatory to confirm disease association. PMID:24652797

Pemphigus vulgaris associated with autoimmune hemolytic anemia and elevated TNF alpha.

PubMed

Ujihara, M; Hamanaka, S; Matsuda, S; Numa, F; Kato, H

1994-01-01

A 76-year-old female was admitted with many bullae and erythema on her trunk and extremities. A biopsy specimen showed significant intercellular edema in the lower epidermis and eosinophilic infiltration into the dermis and the epidermis. Immunofluorescent staining revealed the deposition of IgG in the intercellular area of her prickle cells. From these histologic findings and the typical clinical features, we diagnosed her as having pemphigus vulgaris. Examination of her blood revealed that she also suffered from autoimmune hemolytic anemia. Despite intensive treatment with prednisolone, she finally died. This case is of interest because of its rarity and the TNF alpha detected significantly in the blister fluid of this patient.

Incidence of beta hemolytic streptococcal pharyngitis in adolescent with infectious mononucleosis.

PubMed

Collins, M; Fleisher, G R; Fager, S S

1984-04-01

Reports on the incidence of beta-hemolytic group A streptococci (BHGAS) in the pharynx of patients with infectious mononucleosis (IM) have varied from 3% to 33%. To ascertain the rate of infection, we prospectively performed serial throat cultures and determined anti-streptococcal antibody titers on 45 students with confirmed IM by Epstein-Barr virus-specific serology. One hundred healthy control students had throat cultures for comparison. The rate of recovery of BHGAS was similar in patients with IM (4%) and controls (3%). No students with IM had a fourfold rise of anti-streptococcal antibodies. We conclude that routine culture for BHGAS and/or treatment with antibiotic agents is not indicated in all patients with IM.

Molecular and Phenotypic Analysis of Hemolytic Aeromonas Strains Isolated from Food in Egypt Revealed Clinically Important Multidrug Resistance and Virulence Profiles.

PubMed

Hammad, Ahmed M; Moustafa, Alaa-Eldin H; Mansour, Maha M; Fahmy, Bashier M; Hamada, Mohamed G; Shimamoto, Toshi; Shimamoto, Tadashi

2018-06-01

The aim of this study was to determine the public health significance of hemolytic Aeromonas species isolated from 213 food samples in Egypt, based on their virulence and antimicrobial-resistance potential. We recovered 63 strains, isolated from fish, raw milk, karish cheeses, and ras cheese in 29 (31.18%) of 93, 10 (25.00%) of 40, 13 (32.50%) of 40, and 11 (27.50%) of 40 samples, respectively. The most prevalent virulence gene was alt (50.79%), followed by aerA (34.92%), asa1 (39.68%), ahh1 (20.63%), act (11.11%), and ast (3.17%). Thirteen strains screened in this study carried no hemolysin gene, but only the alt gene, and another eight hemolytic strains screened, carried no virulence gene. The virulence signatures " ahh1+ aerA" and " alt+ act," in which the genes interact synergistically to induce severe diarrhea, were detected in two and four strains, respectively. Most showed resistance to third-generation cephalosporins, aztreonam, and imipenem, which indicates the complexity of the β-lactamase production in our hemolytic Aeromonas strains. Fourteen (22.22%) of 63 strains carried one or more antimicrobial-resistance markers, including the bla CTX-M , bla TEM , tet(A), tet(E), and intI1 genes, which were detected in 6.34, 3.17, 3.17, 4.76, and 14.28% of isolates, respectively. In conclusion, the majority of hemolytic Aeromonas strains isolated from the intestinal contents of healthy fish and naturally contaminated milk and cheeses were not commensal but had developed multidrug-resistance and virulence profiles, indicating an emerging potential health risk. Importantly, screening for certain hemolysin genes may not be reliable in predicting the pathogenic potential of Aeromonas species and, thereby, the safety of analyzed foods. Our findings indicate that specific criteria are required for the phenotypic and molecular analysis of Aeromonas species in food items, particularly those eaten without further treatment, to ensure their safety.

Formulation of long-wavelength indocyanine green nanocarriers

NASA Astrophysics Data System (ADS)

Pansare, Vikram J.; Faenza, William J.; Lu, Hoang; Adamson, Douglas H.; Prud'homme, Robert K.

2017-09-01

Indocyanine green (ICG), a Food and Drug Administration (FDA)-approved fluorophore with excitation and emission wavelengths inside the "optical imaging window," has been incorporated into nanocarriers (NCs) to achieve enhanced circulation time, targeting, and real-time tracking in vivo. While previous studies transferred ICG exogenously into NCs, here, a one-step rapid precipitation process [flash nanoprecipitation (FNP)] creates ICG-loaded NCs with tunable, narrow size distributions from 30 to 180 nm. A hydrophobic ion pair of ICG-tetraoctylammonium or tetradodecylammonium chloride is formed either in situ during FNP or preformed then introduced into the FNP feed stream. The NCs are formulated with cores comprising either vitamin E (VE) or polystyrene (PS). ICG core loadings of 30 wt. % for VE and 10 wt. % for PS are achieved. However, due to a combination of molecular aggregation and Förster quenching, maximum fluorescence (FL) occurs at 10 wt. % core loading. The FL-per-particle scales with core diameter to the third power, showing that FNP enables uniform volume encapsulation. By varying the ICG counter-ion ratio, encapsulation efficiencies above 80% are achieved even in the absence of ion pairing, which rises to 100% with 1∶1 ion pairing. Finally, while ICG ion pairs are shown to be stable in buffer, they partition out of NC cores in under 30 min in the presence of physiological albumin concentrations.

Ternary Interactions and Energy Transfer between Fluorescein Isothiocyanate, Adenosine Triphosphate, and Graphene Oxide Nanocarriers.

PubMed

Ratajczak, Katarzyna; Stobiecka, Magdalena

2017-07-20

The interactions of fluorescent probes and biomolecules with nanocarriers are of key importance to the emerging targeted drug delivery systems. Graphene oxide nanosheets (GONs) as the nanocarriers offer biocompatibility and robust drug binding capacity. The interactions of GONs with fluorophores lead to strong fluorescence quenching, which may interfere with fluorescence bioimaging and biodetection. Herein, we report on the interactions and energy transfers in a model ternary system: GONs-FITC-ATP, where FITC is a model fluorophore (fluorescein isothiocyanate) and ATP is a common biomolecule (adenosine-5'-triphosphate). We have found that FITC fluorescence is considerably quenched by ATP (the quenching constant K SV = 113 ± 22 M -1 ). The temperature coefficient of K SV is positive (α T = 4.15 M -1 deg -1 ). The detailed analysis of a model for internal self-quenching of FITC indicates that the temperature dependence of the net quenching efficiency η for the FITC-ATP pair is dominated by FITC internal self-quenching modes with their contribution estimated at 79%. The quenching of FITC by GONs is much stronger (K SV = 598 ± 29 M -1 ) than that of FITC-ATP and is associated with the formation of supramolecular assemblies bound with hydrogen bonding and π-π stacking interactions. For the analysis of the complex behavior of the ternary system GONs-FITC-ATP, a model of chemisorption of ATP on GONs, with partial blocking of FITC quenching, has been developed. Our results indicate that ATP acts as a moderator for FITC quenching by GONs. The interactions between ATP, FITC, and GONs have been corroborated using molecular dynamics and quantum mechanical calculations.

Polymer-lipid hybrid systems: merging the benefits of polymeric and lipid-based nanocarriers to improve oral drug delivery.

PubMed

Rao, Shasha; Prestidge, Clive A

2016-01-01

A number of biobarriers limit efficient oral drug absorption; both polymer-based and lipid-based nanocarriers have demonstrated properties and delivery mechanisms to overcome these biobarriers in preclinical settings. Moreover, in order to address the multifaceted oral drug delivery challenges, polymer-lipid hybrid systems are now being designed to merge the beneficial features of both polymeric and lipid-based nanocarriers. Recent advances in the development of polymer-lipid hybrids with a specific focus on their viability in oral delivery are reviewed. Three classes of polymer-lipid hybrids have been identified, i.e. lipid-core polymer-shell systems, polymer-core lipid-shell systems, and matrix-type polymer-lipid hybrids. We focus on their application to overcome the various biological barriers to oral drug absorption, as exemplified by selected preclinical studies. Numerous studies have demonstrated the superiority of polymer-lipid hybrid systems to their non-hybrid counterparts in providing improved drug encapsulation, modulated drug release, and improved cellular uptake. These features have encouraged their applications in the delivery of chemotherapeutics, proteins, peptides, and vaccines. With further research expected to optimize the manufacturing and scaling up processes and in-depth pre-clinical pharmacological and toxicological assessments, these multifaceted drug delivery systems will have significant clinical impact on the oral delivery of pharmaceuticals and biopharmaceuticals.

Polymeric nanocarriers for transport modulation across the pulmonary epithelium: dendrimers, polymeric nanoparticles, and their nanoblends.

PubMed

Bharatwaj, Balaji; Dimovski, Radovan; Conti, Denise S; da Rocha, Sandro R P

2014-05-01

The purpose of this study was to (a) Determine the cellular transport and uptake of amine-terminated generation 3 (G3) poly(amido amine) (PAMAM) dendrimers across an in vitro model of the pulmonary epithelium, and the ability to modulate their transport by forming nanoblends of the dendrimers with biodegradable solid polymeric nanoparticles (NPs) and (b) to formulate dendrimer nanocarriers in portable oral inhalation devices and evaluate their aerosol characteristics. To that end, fluorescein isothiocyanate (FITC)-labeled G3 PAMAM dendrimer nanocarriers (DNCs) were synthesized, and also encapsulated within poly lactide-co-glycolide nanoparticles (NPs). Transport and uptake of both DNCs encapsulated within NPs (nanoblends) and unencapsulated DNCs were tracked across polarized monolayers of airway epithelial cells, Calu-3. DNCs were also formulated as core-shell microparticles in pressurized metered-dose inhalers (pMDIs) and their aerodynamic properties evaluated by Andersen cascade impaction. The apparent permeability of DNCs across the airway epithelial model was similar to that of a paracellular marker of comparable molar mass--order of 10(-7) cm s(-1). The transport and cellular internalization of the DNCs can be modulated by formulating them as nanoblends. The transport of the DNCs across the lung epithelium was completely suppressed within the time of the experiment (5 h) when formulated as blends. The encapsulation also prevents saturation of the cellular internalization profile. Nanoblending may be a potential strategy to modulate the rate of transport and cellular uptake of DNCs, and thus be used as a design strategy to achieve enhanced local or systemic drug delivery.

Synthesis and characterization of poly(propylene imine)-dendrimer-grafted gold nanoparticles as nanocarriers of doxorubicin.

PubMed

Golshan, Marzieh; Salami-Kalajahi, Mehdi; Mirshekarpour, Mina; Roghani-Mamaqani, Hossein; Mohammadi, Maryam

2017-07-01

The aim of current work is synthesis 4th-generation-poly(propylene imine) (PPI)-dendrimer modified gold nanoparticles (Au-G4A) as nanocarriers for doxorubicin (DOX) and studying in vitro drug release kinetics from nanocarriers into different media. Accordingly, AuNPs were synthesized by reduction of chloroauric acid (HAuCl 4 ) aqueous solution with trisodium citrate and modified with cysteamine to obtain amine-functionalized (Au-NH 2 ) nanoparticles. Au-NH 2 nanoparticles were used as multifunctional cores and participated in Michael addition of acrylonitrile and reduction process by lithium aluminum hydride (LAH) to synthesize Au-G4A nanoparticles. Also, peripheral primary amine groups of Au-G4A were conjugated with folic acid (FA) (Au-G4F) to study the bioconjugation effect on drug release behavior of nanostructures. Ultraviolet spectroscopy (UV-vis), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA) were used to approve the synthesis of different nanostructures. Finally, Au-G4A and Au-G4F samples were loaded with DOX and exposed to environments with different pH values to examine the release properties of nanostructures. Also, drug release kinetics was investigated by fitting of experimental data with different release models. As a result, synthesized dendritic structures showed Higuchi and Korsmeyer-Peppas models release behavior due to better solubility of drug in release media with respect to dendrimer cavities and drug release through polymeric matrix respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

A De Novo Deletion in the Regulators of Complement Activation Cluster Producing a Hybrid Complement Factor H/Complement Factor H-Related 3 Gene in Atypical Hemolytic Uremic Syndrome.

PubMed

Challis, Rachel C; Araujo, Geisilaine S R; Wong, Edwin K S; Anderson, Holly E; Awan, Atif; Dorman, Anthony M; Waldron, Mary; Wilson, Valerie; Brocklebank, Vicky; Strain, Lisa; Morgan, B Paul; Harris, Claire L; Marchbank, Kevin J; Goodship, Timothy H J; Kavanagh, David

2016-06-01

The regulators of complement activation cluster at chromosome 1q32 contains the complement factor H (CFH) and five complement factor H-related (CFHR) genes. This area of the genome arose from several large genomic duplications, and these low-copy repeats can cause genome instability in this region. Genomic disorders affecting these genes have been described in atypical hemolytic uremic syndrome, arising commonly through nonallelic homologous recombination. We describe a novel CFH/CFHR3 hybrid gene secondary to a de novo 6.3-kb deletion that arose through microhomology-mediated end joining rather than nonallelic homologous recombination. We confirmed a transcript from this hybrid gene and showed a secreted protein product that lacks the recognition domain of factor H and exhibits impaired cell surface complement regulation. The fact that the formation of this hybrid gene arose as a de novo event suggests that this cluster is a dynamic area of the genome in which additional genomic disorders may arise. Copyright © 2016 by the American Society of Nephrology.

Development of mixed-type autoimmune hemolytic anemia and Evans' syndrome following chicken pox infection in a case of low-titer cold agglutinin disease.

PubMed

Tanaka, Yumi; Masuya, Masahiro; Katayama, Naoyuki; Miyata, Eri; Sugimoto, Yuka; Shibasaki, Tetsunori; Yamamura, Kentaro; Ohishi, Kohshi; Minami, Nobuyuki; Shiku, Hiroshi; Nobori, Tsutomu

2006-10-01

We describe a patient with low-titer cold agglutinin disease (CAD) who developed mixed-type autoimmune hemolytic anemia (AIHA) and idiopathic thrombocytopenia following chicken pox infection. At least 1 year before admission to hospital, the patient had mild hemolytic anemia associated with low-titer cold agglutinins. A severe hemolytic crisis and thrombocytopenia (Evans' syndrome) occurred several days after infection with chicken pox, and the patient was referred to our hospital. Serological findings revealed the presence of both cold agglutinins and warm-reactive autoantibodies against erythrocytes, and the diagnosis was mixed-type AIHA. Following steroid therapy, the hemoglobin (Hb) level and platelet count improved. The patient was closely followed over a 10-year period with recurrent documented hemolysis after viral or bacterial infections. Warm-reactive autoantibodies have not been detected in the last 2 years, and only the immunoglobulin M anti-I cold agglutinins with a low titer and wide thermal amplitude have remained unchanged. Therefore, the patient has received at least 10 mg prednisolone daily to maintain a Hb level of 10 g/dL. To the best of our knowledge, no adult case of low-titer CAD that has evolved into mixed-type AIHA and Evans' syndrome after chicken pox infection has been previously reported in the literature.

Intravascular hemolysis induced by phospholipases A2 from the venom of the Eastern coral snake, Micrurus fulvius: Functional profiles of hemolytic and non-hemolytic isoforms.

PubMed

Fernández, María Laura; Quartino, Pablo Yunes; Arce-Bejarano, Ruth; Fernández, Julián; Camacho, Luis F; Gutiérrez, José María; Kuemmel, Daniel; Fidelio, Gerardo; Lomonte, Bruno

2018-04-01

A unique feature of the venom of Micrurus fulvius (Eastern coral snake) is its ability to induce severe intravascular hemolysis in particular species, such as dogs or mice. This effect was previously shown to be induced by distinct phospholipase A 2 (PLA 2 ) isoforms which cause direct hemolysis in vitro, an uncommon finding for such enzymes. The functional profiles of PLA 2 -17, a direct hemolytic enzyme, and PLA 2 -12, a co-existing venom isoform lacking such effect, were compared. The enzymes differed not only in their ability to cause intravascular hemolysis: PLA 2 -17 additionally displayed lethal, myotoxic, and anticoagulant actions, whereas PLA 2 -12 lacked these effects. PLA 2 -12 was much more active in hydrolyzing a monodisperse synthetic substrate than PLA 2 -17, but the catalytic activity of latter was notably higher on a micellar substrate, or towards pure phospholipid artificial monolayers under controlled lateral pressures. Interestingly, PLA 2 -17 could hydrolyze substrate at a pressure of 20 mN m -1 , in contrast to PLA 2 -12 or the non-toxic pancreatic PLA 2 . This suggests important differences in the monolayer penetrating power, which could be related to differences in toxicity. Comparative examination of primary structures and predicted three-dimensional folding of PLA 2 -12 and PLA 2 -17, revealed that differences concentrate in their N-terminal and central regions, leading to variations of the surface properties at the membrane interacting interface. PLA 2 -17 presents a less basic interfacial surface than PLA 2 -12, but more bulky aromatic residues, which could be associated to its higher membrane-penetrating strength. Altogether, these structural and functional comparative observations suggest that the ability of PLA 2 s to penetrate substrate interfaces could be a major determinant of toxicity, perhaps more important than protein surface charge. Copyright © 2017 Elsevier B.V. All rights reserved.

Cyclosporine Induces Endothelial Cell Release of Complement-Activating Microparticles

PubMed Central

Renner, Brandon; Klawitter, Jelena; Goldberg, Ryan; McCullough, James W.; Ferreira, Viviana P.; Cooper, James E.; Christians, Uwe

2013-01-01

Defective control of the alternative pathway of complement is an important risk factor for several renal diseases, including atypical hemolytic uremic syndrome. Infections, drugs, pregnancy, and hemodynamic insults can trigger episodes of atypical hemolytic uremic syndrome in susceptible patients. Although the mechanisms linking these clinical events with disease flares are unknown, recent work has revealed that each of these clinical conditions causes cells to release microparticles. We hypothesized that microparticles released from injured endothelial cells promote intrarenal complement activation. Calcineurin inhibitors cause vascular and renal injury and can trigger hemolytic uremic syndrome. Here, we show that endothelial cells exposed to cyclosporine in vitro and in vivo release microparticles that activate the alternative pathway of complement. Cyclosporine-induced microparticles caused injury to bystander endothelial cells and are associated with complement-mediated injury of the kidneys and vasculature in cyclosporine-treated mice. Cyclosporine-induced microparticles did not bind factor H, an alternative pathway regulatory protein present in plasma, explaining their complement-activating phenotype. Finally, we found that in renal transplant patients, the number of endothelial microparticles in plasma increases 2 weeks after starting tacrolimus, and treatment with tacrolimus associated with increased C3 deposition on endothelial microparticles in the plasma of some patients. These results suggest that injury-associated release of endothelial microparticles is an important mechanism by which systemic insults trigger intravascular complement activation and complement-dependent renal diseases. PMID:24092930

Recommendations regarding splenectomy in hereditary hemolytic anemias

PubMed Central

Iolascon, Achille; Andolfo, Immacolata; Barcellini, Wilma; Corcione, Francesco; Garçon, Loïc; De Franceschi, Lucia; Pignata, Claudio; Graziadei, Giovanna; Pospisilova, Dagmar; Rees, David C.; de Montalembert, Mariane; Rivella, Stefano; Gambale, Antonella; Russo, Roberta; Ribeiro, Leticia; Vives-Corrons, Jules; Martinez, Patricia Aguilar; Kattamis, Antonis; Gulbis, Beatrice; Cappellini, Maria Domenica; Roberts, Irene; Tamary, Hannah

2017-01-01

Hereditary hemolytic anemias are a group of disorders with a variety of causes, including red cell membrane defects, red blood cell enzyme disorders, congenital dyserythropoietic anemias, thalassemia syndromes and hemoglobinopathies. As damaged red blood cells passing through the red pulp of the spleen are removed by splenic macrophages, splenectomy is one possible therapeutic approach to the management of severely affected patients. However, except for hereditary spherocytosis for which the effectiveness of splenectomy has been well documented, the efficacy of splenectomy in other anemias within this group has yet to be determined and there are concerns regarding short- and long-term infectious and thrombotic complications. In light of the priorities identified by the European Hematology Association Roadmap we generated specific recommendations for each disorder, except thalassemia syndromes for which there are other, recent guidelines. Our recommendations are intended to enable clinicians to achieve better informed decisions on disease management by splenectomy, on the type of splenectomy and the possible consequences. As no randomized clinical trials, case control or cohort studies regarding splenectomy in these disorders were found in the literature, recommendations for each disease were based on expert opinion and were subsequently critically revised and modified by the Splenectomy in Rare Anemias Study Group, which includes hematologists caring for both adults and children. PMID:28550188

Clinical Outcomes of Splenectomy in Children: Report of the Splenectomy in Congenital Hemolytic Anemia (SICHA) Registry

PubMed Central

Rice, Henry E; Englum, Brian R; Rothman, Jennifer; Leonard, Sarah; Reiter, Audra; Thornburg, Courtney; Brindle, Mary; Wright, Nicola; Heeney, Matthew M; Smithers, Charles; Brown, Rebeccah L; Kalfa, Theodosia; Langer, Jacob C; Cada, Michaela; Oldham, Keith T; Scott, J Paul; St. Peter, Shawn; Sharma, Mukta; Davidoff, Andrew M.; Nottage, Kerri; Bernabe, Kathryn; Wilson, David B; Dutta, Sanjeev; Glader, Bertil; Crary, Shelley E; Dassinger, Melvin S; Dunbar, Levette; Islam, Saleem; Kumar, Manjusha; Rescorla, Fred; Bruch, Steve; Campbell, Andrew; Austin, Mary; Sidonio, Robert; Blakely, Martin L

2014-01-01

The outcomes of children with congenital hemolytic anemia (CHA) undergoing total splenectomy (TS) or partial splenectomy (PS) remain unclear. In this study, we collected data from 100 children with CHA who underwent TS or PS from 2005–2013 at 16 sites in the Splenectomy in Congenital Hemolytic Anemia (SICHA) consortium using a patient registry. We analyzed demographics and baseline clinical status, operative details, and outcomes at 4, 24, and 52 weeks after surgery. Results were summarized as hematologic outcomes, short-term adverse events (AEs) (≤ 30 days after surgery), and long-term AEs (31–365 days after surgery). For children with hereditary spherocytosis, after surgery there was an increase in hemoglobin (baseline 10.1 ± 1.8 gm/dl, 52 week 12.8 ± 1.6 gm/dl; mean ± SD), decrease in reticulocyte and bilirubin as well as control of symptoms. Children with sickle cell disease had control of clinical symptoms after surgery, but had no change in hematologic parameters. There was an 11% rate of short-term AEs and 11% rate of long-term AEs. As we accumulate more subjects and longer follow-up, use of a patient registry should enhance our capacity for clinical trials and engage all stakeholders in the decision-making process. PMID:25382665

Limitations of a hemolytic plaque assay for IgG-anti-IgG rheumatoid factor-producing cells.

PubMed

Venn, A J; Dresser, D W

1987-09-24

An attempt has been made to develop a hemolytic plaque assay capable of detecting homophile IgG rheumatoid factor (RF)-producing cells. Anti-immunoglobulin allotype-developing reagents were used to distinguish between target and effector IgG. The hemolytic assay has been used to demonstrate an apparently high level of homophile IgM and IgG RF-producing cells in the spleens and lymph nodes of mice stimulated by LPS. However, it appears that a large proportion of the plaques obtained in these assays are due to an artefact resulting from cross-linking of target and effector molecules by the developing reagents. In the case of IgM RF the artefact depends on the presence of a small contamination of the target IgG by IgM, allowing cross-linking of target and effector IgM by the anti-mu-specific developing reagent. With the IgG RF, cross-reactivity of the rabbit anti-Ighb allotype-developing serum for the 'wrong' (Igha) allotype, normally undetectable, becomes sufficient to be biologically relevant when the developing antibody is complexed by being bound to its target (Ighb) allotype. Nevertheless anti-allotype reagents may afford an accurate means of detecting homophile IgG RF producing cells using other assay systems.

Single-Step Assembly of Multi-Modal Imaging Nanocarriers: MRI and Long-Wavelength Fluorescence Imaging

PubMed Central

Pinkerton, Nathalie M.; Gindy, Marian E.; Calero-DdelC, Victoria L.; Wolfson, Theodore; Pagels, Robert F.; Adler, Derek; Gao, Dayuan; Li, Shike; Wang, Ruobing; Zevon, Margot; Yao, Nan; Pacheco, Carlos; Therien, Michael J.; Rinaldi, Carlos; Sinko, Patrick J.

2015-01-01

MRI and NIR-active, multi-modal Composite NanoCarriers (CNCs) are prepared using a simple, one-step process, Flash NanoPrecipitation (FNP). The FNP process allows for the independent control of the hydrodynamic diameter, co-core excipient and NIR dye loading, and iron oxide-based nanocrystal (IONC) content of the CNCs. In the controlled precipitation process, 10 nm IONCs are encapsulated into poly(ethylene glycol) stabilized CNCs to make biocompatible T2 contrast agents. By adjusting the formulation, CNC size is tuned between 80 and 360 nm. Holding the CNC size constant at an intensity weighted average diameter of 99 ± 3 nm (PDI width 28 nm), the particle relaxivity varies linearly with encapsulated IONC content ranging from 66 to 533 mM-1s-1 for CNCs formulated with 4 to 16 wt% IONC. To demonstrate the use of CNCs as in vivo MRI contrast agents, CNCs are surface functionalized with liver targeting hydroxyl groups. The CNCs enable the detection of 0.8 mm3 non-small cell lung cancer metastases in mice livers via MRI. Incorporating the hydrophobic, NIR dye PZn3 into CNCs enables complementary visualization with long-wavelength fluorescence at 800 nm. In vivo imaging demonstrates the ability of CNCs to act both as MRI and fluorescent imaging agents. PMID:25925128

Polycatechol nanosheet: a superior nanocarrier for highly effective chemo-photothermal synergistic therapy in vivo

NASA Astrophysics Data System (ADS)

Bai, J.; Jia, X. D.; Ma, Z. F.; Jiang, X. E.; Sun, X. P.

2016-02-01

The integration of phototherapy and chemotherapy in a single system holds great promise to improve the therapeutic efficacy of tumor treatment, but it remains a key challenge. In this study, we describe our recent finding that polycatechol nanosheet (PCCNS) can be facilely prepared on a large scale via chemical polymerization at 4 °C, as an effective nanocarrier for loading high-density CuS nanocrystals as a photothermal agent. The resulting CuS/PCCNS nanocomposites exhibit good biocompatibility, strong stability, and a high photothermal conversion efficiency of ~45.7%. The subsequent loading of anticancer drug doxorubicin (Dox) creates a superior theranostic agent with pH- and heat-responsive drug release, leading to almost complete destruction of mouse cervical tumor under NIR laser irradiation. This development offers an attractive theranostic agent for in vivo chemo-photothermal synergistic therapy toward biomedical applications.The integration of phototherapy and chemotherapy in a single system holds great promise to improve the therapeutic efficacy of tumor treatment, but it remains a key challenge. In this study, we describe our recent finding that polycatechol nanosheet (PCCNS) can be facilely prepared on a large scale via chemical polymerization at 4 °C, as an effective nanocarrier for loading high-density CuS nanocrystals as a photothermal agent. The resulting CuS/PCCNS nanocomposites exhibit good biocompatibility, strong stability, and a high photothermal conversion efficiency of ~45.7%. The subsequent loading of anticancer drug doxorubicin (Dox) creates a superior theranostic agent with pH- and heat-responsive drug release, leading to almost complete destruction of mouse cervical tumor under NIR laser irradiation. This development offers an attractive theranostic agent for in vivo chemo-photothermal synergistic therapy toward biomedical applications. Electronic supplementary information (ESI) available: The calculation of the photothermal conversion

A novel dendritic nanocarrier of polyamidoamine-polyethylene glycol-cyclic RGD for “smart” small interfering RNA delivery and in vitro antitumor effects by human ether-à-go-go-related gene silencing in anaplastic thyroid carcinoma cells

PubMed Central

Li, Guanhua; Hu, Zuojun; Yin, Henghui; Zhang, Yunjian; Huang, Xueling; Wang, Shenming; Li, Wen

2013-01-01

The application of RNA interference techniques is promising in gene therapeutic approaches, especially for cancers. To improve safety and efficiency of small interfering RNA (siRNA) delivery, a triblock dendritic nanocarrier, polyamidoamine-polyethylene glycol-cyclic RGD (PAMAM-PEG-cRGD), was developed and studied as an siRNA vector targeting the human ether-à-go-go-related gene (hERG) in human anaplastic thyroid carcinoma cells. Structure characterization, particle size, zeta potential, and gel retardation assay confirmed that complete triblock components were successfully synthesized with effective binding capacity of siRNA in this triblock nanocarrier. Cytotoxicity data indicated that conjugation of PEG significantly alleviated cytotoxicity when compared with unmodified PAMAM. PAMAM-PEG-cRGD exerted potent siRNA cellular internalization in which transfection efficiency measured by flow cytometry was up to 68% when the charge ratio (N/P ratio) was 3.5. Ligand-receptor affinity together with electrostatic interaction should be involved in the nano-siRNA endocytosis mechanism and we then proved that attachment of cRGD enhanced cellular uptake via RGD-integrin recognition. Gene silencing was evaluated by reverse transcription polymerase chain reaction and PAMAM-PEG-cRGD-siRNA complex downregulated the expression of hERG to 26.3% of the control value. Furthermore, gene knockdown of hERG elicited growth suppression as well as activated apoptosis by means of abolishing vascular endothelial growth factor secretion and triggering caspase-3 cascade in anaplastic thyroid carcinoma cells. Our study demonstrates that this novel triblock polymer, PAMAM-PEG-cRGD, exhibits negligible cytotoxicity, effective transfection, “smart” cancer targeting, and therefore is a promising siRNA nanocarrier. PMID:23569377

Novel designed VmCT1 analogs with increased antimicrobial activity.

PubMed

Pedron, Cibele Nicolaski; Torres, Marcelo Der Torossian; Lima, Julia Aparecida da Silva; Silva, Pedro Ismael; Silva, Fernanda Dias; Oliveira, Vani Xavier

2017-01-27

Antimicrobial peptides are biologically active molecules produced by a wide range of organisms as an essential component of the innate immune response. They have recently attracted great interest, since they have antimicrobial activity against a broad spectrum of microorganisms. VmCT1 is a cationic peptide from the venom of Vaejovis mexicanus smithi scorpions, which presents antibacterial activity and tends to helical structures. Its analogs were synthesized, characterized and the conformational studies were performed by circular dichroism. The peptides were designed to verify if the single and double substitutions proposed at the hydrophilic and hydrophobic portions of the amphipathic structure would alter antimicrobial activity against Gram-negative and Gram-positive bacteria, yeast and filamentous fungus, besides the hemolytic activity in human erythrocytes. Total charge of the peptides were modified from +2 to +3 by the introduction of a Lysine residue in the hydrophilic face of the amphiphilic helical structure leading to enhanced antimicrobial activity. [K] 11 -VmCT1-NH 2 presented the lower MIC value against the microorganisms (from 0.39 to 6.25 μmol L -1 ), however it showed higher hemolytic activity. The other Lysine-substituted analogs presented also lower MIC values ranging from 0.39 to 25 μmol L -1 for the microorganisms assessed. The circular dichroism spectra analyses suggest that the Lysine-substituted analogs tend to adopt helical structures in trifluoroethanol solution and vesicles (f H : 0.43-1), however they were coiled in water. Alanine substitution by a Glutamic acid residue in the hydrophilic face promotes the increase of polar angle in [E] 4 -VmCT1-NH 2 analog, which was important to led lower hemolytic activity (MHC value = 25 μmol L -1 ). [W] 9 -VmCT1-NH 2 and [E] 4 [W] 9 -VmCT1-NH 2 were designed to favors hydrophobic interactions by the introduction of Tryptophan residue. [W] 9 -VmCT1-NH 2 presented MIC values lower or

A cluster of Escherichia coli O157:H7 infections with the hemolytic-uremic syndrome and death in California. A mandate for improved surveillance.

PubMed Central

Shefer, A M; Koo, D; Werner, S B; Mintz, E D; Baron, R; Wells, J G; Barrett, T J; Ginsberg, M; Bryant, R; Abbott, S; Griffin, P M

1996-01-01

In mid-January 1993, an outbreak of Escherichia coli O157:H7 infections associated with eating hamburger patties at a fast-food restaurant chain (chain A) was reported in Washington State. From mid-December to mid-January, 9 cases of E coli O157:H7-associated bloody diarrhea and the hemolytic-uremic syndrome had been reported in San Diego County, California. A total of 34 persons had bloody diarrhea, the hemolytic-uremic syndrome, or E coli O157:H7 organisms isolated from stool during the period November 15, 1992, through January 31, 1993. Organisms of E coli O157:H7 identified from 6 persons were indistinguishable from those of the Washington outbreak strain. Illness was associated with eating at chain A restaurants in San Diego (odds ratio, 13; 95% confidence interval, 1.7, 99) and with eating regular-sized hamburgers (odds ratio, undefined; lower-limit 95% confidence interval, 1.3). Improved surveillance by mandating laboratory- and physician-based reporting of cases of E coli O157:H7 infection and the hemolytic-uremic syndrome might have alerted health officials to this outbreak sooner, which could have resulted in earlier investigation and the institution of measures to prevent more cases. Images Figure 1. PMID:8855679

Formulation of long-wavelength indocyanine green nanocarriers.

PubMed

Pansare, Vikram J; Faenza, William J; Lu, Hoang; Adamson, Douglas H; Prud'homme, Robert K

2017-09-01

Indocyanine green (ICG), a Food and Drug Administration (FDA)-approved fluorophore with excitation and emission wavelengths inside the "optical imaging window," has been incorporated into nanocarriers (NCs) to achieve enhanced circulation time, targeting, and real-time tracking in vivo. While previous studies transferred ICG exogenously into NCs, here, a one-step rapid precipitation process [flash nanoprecipitation (FNP)] creates ICG-loaded NCs with tunable, narrow size distributions from 30 to 180 nm. A hydrophobic ion pair of ICG-tetraoctylammonium or tetradodecylammonium chloride is formed either in situ during FNP or preformed then introduced into the FNP feed stream. The NCs are formulated with cores comprising either vitamin E (VE) or polystyrene (PS). ICG core loadings of 30 wt. % for VE and 10 wt. % for PS are achieved. However, due to a combination of molecular aggregation and Förster quenching, maximum fluorescence (FL) occurs at 10 wt. % core loading. The FL-per-particle scales with core diameter to the third power, showing that FNP enables uniform volume encapsulation. By varying the ICG counter-ion ratio, encapsulation efficiencies above 80% are achieved even in the absence of ion pairing, which rises to 100% with 1∶1 ion pairing. Finally, while ICG ion pairs are shown to be stable in buffer, they partition out of NC cores in under 30 min in the presence of physiological albumin concentrations. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

The potential of magneto-electric nanocarriers for drug delivery.

PubMed

Kaushik, Ajeet; Jayant, Rahul Dev; Sagar, Vidya; Nair, Madhavan

2014-10-01

The development and design of personalized nanomedicine for better health quality is receiving great attention. In order to deliver and release a therapeutic concentration at the target site, novel nanocarriers (NCs) were designed, for example, magneto-electric (ME) which possess ideal properties of high drug loading, site-specificity and precise on-demand controlled drug delivery. This review explores the potential of ME-NCs for on-demand and site-specific drug delivery and release for personalized therapeutics. The main features including effect of magnetism, improvement in drug loading, drug transport across blood-brain barriers and on-demand controlled release are also discussed. The future directions and possible impacts on upcoming nanomedicine are highlighted. Numerous reports suggest that there is an urgent need to explore novel NC formulations for safe and targeted drug delivery and release at specific disease sites. The challenges of formulation lie in the development of NCs that improve biocompatibility and surface modifications for optimum drug loading/preservation/transmigration and tailoring of electrical-magnetic properties for on-demand drug release. Thus, the development of novel NCs is anticipated to overcome the problems of targeted delivery of therapeutic agents with desired precision that may lead to better patient compliance.

Investigation of whether the acute hemolysis associated with Rho(D) immune globulin intravenous (human) administration for treatment of immune thrombocytopenic purpura is consistent with the acute hemolytic transfusion reaction model

PubMed Central

Gaines, Ann Reed; Lee-Stroka, Hallie; Byrne, Karen; Scott, Dorothy E.; Uhl, Lynne; Lazarus, Ellen; Stroncek, David F.

2012-01-01

BACKGROUND Immune thrombocytopenic purpura and secondary thrombocytopenia patients treated with Rho(D) immune globulin intravenous (human; anti-D IGIV) have experienced acute hemolysis, which is inconsistent with the typical presentation of extravascular hemolysis—the presumed mechanism of action of anti-D IGIV. Although the mechanism of anti-D-IGIV–associated acute hemolysis has not been established, the onset, signs/symptoms, and complications appear consistent with the intravascular hemolysis of acute hemolytic transfusion reactions (AHTRs). In transfusion medicine, the red blood cell (RBC) antigen-antibody incompatibility(-ies) that precipitate AHTRs can be detected in vitro with compatibility testing. Under the premise that anti-D-IGIV–associated acute hemolysis results from RBC antigen-antibody–mediated complement activation, this study evaluated whether the incompatibility(-ies) could be detected in vitro with a hemolysin assay, which would support the AHTR model as the hemolytic mechanism. STUDY DESIGN AND METHODS Seven anti-D IGIV lots were tested to determine the RBC antibody identities in those lots, including four lots that had been implicated in acute hemolytic episodes. Hemolysin assays were performed that tested each of 73 RBC specimens against each lot, including the RBCs of one patient who had experienced acute hemolysis after anti-D IGIV administration. RESULTS Only two anti-D IGIV lots contained RBC antibodies beyond those expected. No hemolysis endpoint was observed in any of the hemolysin assays. CONCLUSION Although the findings did not support the AHTR model, the results are reported to contribute knowledge about the mechanism of anti-D-IGIV–associated acute hemolysis and to prompt continued investigation into cause(s), prediction, and prevention of this potentially serious adverse event. PMID:19220820

In vitro skin permeation and anti-atopic efficacy of lipid nanocarriers containing water soluble extracts of Houttuynia cordata.

PubMed

Kwon, Taek Kwan; Kim, Jin-Chul

2014-10-01

The aims of this work are to enhance the in vitro skin permeation of Houttuynia cordata (water-soluble extract of H. cordata; HCWSE) and to boost the efficacy of HCWSE against atopic dermatitis (AD) - like skin lesion in hairless mice using lipid nano-carriers (liposome and cubosome). HCWSE was obtained by a hot water extraction. Monoolein cubosomal suspension containing HCWSE and egg phosphatidylcholine liposomal suspension containing the same was prepared by a sonication and a film hydration method, respectively. The lipid nano-carriers, especially cubosome, enhanced the in vitro skin permeation of HCWSE. The inhibitory effects of HCWSE-containing lipid carrier suspensions on the development of 1-chloro-2,4-dinitrobenzene (DNCB)-induced AD-like skin lesion in hairless mice were investigated by observing appearance of skin surface, serum immunoglobulin E (IgE) level and cytokine expression. HCWSE-containing preparations suppressed IgE production and interleukin 4 expression, whereas they promoted interferon gamma expression. The order of lymphocyte (B-cell, Th1 cell and Th2 cell) modulating effect was HCWSE-containing cubosomal suspension > HCWSE-containing liposomal suspension > HCWSE solution in phosphate buffered saline, indicating that the cubosomal suspension, among the preparations, was the most efficacious in inhibiting the development of DNCB-induced AD-like skin lesion. It is believed that the cubosomal suspension containing HCWSE would be an efficacious preparation for the treatment of AD.

Ethosomal nanocarriers: the impact of constituents and formulation techniques on ethosomal properties, in vivo studies, and clinical trials.

PubMed

Abdulbaqi, Ibrahim M; Darwis, Yusrida; Khan, Nurzalina Abdul Karim; Assi, Reem Abou; Khan, Arshad A

2016-01-01

Ethosomal systems are novel lipid vesicular carriers containing a relatively high percentage of ethanol. These nanocarriers are especially designed for the efficient delivery of therapeutic agents with different physicochemical properties into deep skin layers and across the skin. Ethosomes have undergone extensive research since they were invented in 1996; new compounds were added to their initial formula, which led to the production of new types of ethosomal systems. Different preparation techniques are used in the preparation of these novel carriers. For ease of application and stability, ethosomal dispersions are incorporated into gels, patches, and creams. Highly diverse in vivo models are used to evaluate their efficacy in dermal/transdermal delivery, in addition to clinical trials. This article provides a detailed review of the ethosomal systems and categorizes them on the basis of their constituents to classical ethosomes, binary ethosomes, and transethosomes. The differences among these systems are discussed from several perspectives, including the formulation, size, ζ-potential (zeta potential), entrapment efficiency, skin-permeation properties, and stability. This paper gives a detailed review on the effects of ethosomal system constituents, preparation methods, and their significant roles in determining the final properties of these nanocarriers. Furthermore, the novel pharmaceutical dosage forms of ethosomal gels, patches, and creams are highlighted. The article also provides detailed information regarding the in vivo studies and clinical trials conducted for the evaluation of these vesicular systems.

Ethosomal nanocarriers: the impact of constituents and formulation techniques on ethosomal properties, in vivo studies, and clinical trials

PubMed Central

Abdulbaqi, Ibrahim M; Darwis, Yusrida; Khan, Nurzalina Abdul Karim; Assi, Reem Abou; Khan, Arshad A

2016-01-01

Ethosomal systems are novel lipid vesicular carriers containing a relatively high percentage of ethanol. These nanocarriers are especially designed for the efficient delivery of therapeutic agents with different physicochemical properties into deep skin layers and across the skin. Ethosomes have undergone extensive research since they were invented in 1996; new compounds were added to their initial formula, which led to the production of new types of ethosomal systems. Different preparation techniques are used in the preparation of these novel carriers. For ease of application and stability, ethosomal dispersions are incorporated into gels, patches, and creams. Highly diverse in vivo models are used to evaluate their efficacy in dermal/transdermal delivery, in addition to clinical trials. This article provides a detailed review of the ethosomal systems and categorizes them on the basis of their constituents to classical ethosomes, binary ethosomes, and transethosomes. The differences among these systems are discussed from several perspectives, including the formulation, size, ζ-potential (zeta potential), entrapment efficiency, skin-permeation properties, and stability. This paper gives a detailed review on the effects of ethosomal system constituents, preparation methods, and their significant roles in determining the final properties of these nanocarriers. Furthermore, the novel pharmaceutical dosage forms of ethosomal gels, patches, and creams are highlighted. The article also provides detailed information regarding the in vivo studies and clinical trials conducted for the evaluation of these vesicular systems. PMID:27307730

Transport of dendrimer nanocarriers through epithelial cells via the transcellular route.

PubMed

Jevprasesphant, Rachaneekorn; Penny, Jeffrey; Attwood, David; D'Emanuele, Antony

2004-06-18

The mechanism of transport of G3 PAMAM and surface-modified (with lauroyl chains) G3 PAMAM dendrimer nanocarriers across Caco-2 cell monolayers has been investigated. Flow-cytometry studies following quenching of extracellular fluorescence demonstrated the cellular internalisation of dendrimers. Optical sectioning of cells incubated with fluorescein isothiocyanate (FITC)-conjugated dendrimer and lauroyl-dendrimer using confocal laser scanning microscopy revealed colocalisation of a marker for cell nuclei (4',6-diamidino-2-phenylindole, DAPI) and FITC fluorescence, also suggesting cellular internalisation of dendrimers. Transmission electron microscopic analyses of cells incubated with gold-labelled G3 PAMAM dendrimers confirmed endocytosis-mediated cellular internalisation when dendrimers were applied to the apical domain of Caco-2 cells. These findings are in agreement with our previous studies using Caco-2 cell monolayers that showed a significant decrease of dendrimer uptake in the presence of colchicine (endocytosis inhibitor) and when temperature was reduced from 37 to 4 degrees C. Copyright 2004 Elsevier B.V.

Erythrocytic Pyruvate Kinase Mutations Causing Hemolytic Anemia, Osteosclerosis, and Secondary Hemochromatosis in Dogs

PubMed Central

Gultekin, G. Inal; Raj, K.; Foureman, P.; Lehman, S.; Manhart, K.; Abdulmalik, O.; Giger, U.

2013-01-01

Background Erythrocytic pyruvate kinase (PK) deficiency, first documented in Basenjis, is the most common inherited erythroenzymopathy in dogs. Objectives To report 3 new breed-specific PK-LR gene mutations and a retrospective survey of PK mutations in a small and selected group of Beagles and West Highland White Terriers (WHWT). Animals Labrador Retrievers (2 siblings, 5 unrelated), Pugs (2 siblings, 1 unrelated), Beagles (39 anemic, 29 other), WHWTs (22 anemic, 226 nonanemic), Cairn Terrier (n = 1). Methods Exons of the PK-LR gene were sequenced from genomic DNA of young dogs (<2 years) with persistent highly regenerative hemolytic anemia. Results A nonsense mutation (c.799C>T) resulting in a premature stop codon was identified in anemic Labrador Retriever siblings that had osteosclerosis, high serum ferritin concentrations, and severe hepatic secondary hemochromatosis. Anemic Pug and Beagle revealed 2 different missense mutations (c.848T>C, c.994G>A, respectively) resulting in intolerable amino acid changes to protein structure and enzyme function. Breed-specific mutation tests were developed. Among the biased group of 248 WHWTs, 9% and 35% were homozygous (affected) and heterozygous, respectively, for the previously described mutation (mutant allele frequency 0.26). A PK-deficient Cairn Terrier had the same insertion mutation as the affected WHWTs. Of the selected group of 68 Beagles, 35% were PK-deficient and 3% were carriers (0.37). Conclusions and Clinical Importance Erythrocytic PK deficiency is caused by different mutations in different dog breeds and causes chronic severe hemolytic anemia, hemosiderosis, and secondary hemochromatosis because of chronic hemolysis and, an as yet unexplained osteosclerosis. The newly developed breed-specific mutation assays simplify the diagnosis of PK deficiency. PMID:22805166

Reversal of multidrug resistance in MCF-7/Adr cells by codelivery of doxorubicin and BCL2 siRNA using a folic acid-conjugated polyethylenimine hydroxypropyl-β-cyclodextrin nanocarrier

PubMed Central

Li, Jin-Ming; Zhang, Wei; Su, Hua; Wang, Yuan-Yuan; Tan, Cai-Ping; Ji, Liang-Nian; Mao, Zong-Wan

2015-01-01

Systemic administration of chemotherapy for cancer often faces drug resistance, limiting its applications in cancer therapy. In this study, we developed a simple multifunctional nanocarrier based on polyethylenimine (PEI) to codeliver doxorubicin (DOX) and BCL2 small interfering RNA (siRNA) for overcoming multidrug resistance (MDR) and enhancing apoptosis in MCF-7/Adr cancer cells by combining chemotherapy and RNA interference (RNAi) therapy. The low-molecular-weight branch PEI was used to conjugate hydroxypropyl-β-cyclodextrin (HP-β-CD) and folic acid (FA), forming the codelivery nanocarrier (FA-HP-β-CD-PEI) to encapsulate DOX with the cavity HP-β-CD and bind siRNA with the positive charge of PEI for tumor-targeting codelivering drugs. The drug-loaded nanocomplexes (FA-HP-β-CD-PEI/DOX/siRNA) showed uniform size distribution, high cellular uptake, and significant gene suppression of BCL2, displaying the potential of overcoming MDR for enhancing the effect of anticancer drugs. Furthermore, the nanocomplexes achieved significant cell apoptosis through a mechanism of downregulating the antiapoptotic protein BCL2, resulted in improving therapeutic efficacy of the coadministered DOX by tumor targeting and RNA interference. Our study indicated that combined RNAi therapy and chemotherapy using our functional codelivery nanocarrier could overcome MDR and enhance apoptosis in MDR cancer cells for a potential application in treating MDR cancers. PMID:25960653

Hemolytic uremic syndrome (HUS) secondary to cobalamin C (cblC) disorder.

PubMed

Sharma, Ajay P; Greenberg, Cheryl R; Prasad, Asuri N; Prasad, Chitra

2007-12-01

Diarrhea-positive hemolytic uremic syndrome (HUS) is a common cause of acute renal failure in children. Diarrhea-negative (D-), or atypical HUS, is etiologically distinct. A Medline search identified seven previously reported D- cases of HUS secondary to cobalamin C (cblC) disease presenting in infancy. An infantile presentation is reported to be associated with a high mortality rate (6/7 cases). We describe the results of a 5-year longitudinal follow-up in a child diagnosed with D- HUS secondary to cblC disease in infancy. Mutation analysis in this patient identified homozygosity for the 271 dupA mutation (c.271 dupA) in the cblC MMACHC gene. We briefly review the published experience in cblC-associated HUS to highlight the clinical characteristics of this uncommon, but potentially treatable, condition.

A case of red-cell adenosine deaminase overproduction associated with hereditary hemolytic anemia found in Japan.

PubMed

Miwa, S; Fujii, H; Matsumoto, N; Nakatsuji, T; Oda, S; Asano, H; Asano, S

1978-01-01

A case of red cell adenosine deaminase (ADA) overproduction associated with hereditary hemolytic anemia is reported here. This appears to be the second report. Proband is a 38-year-old Japanese male who had hemoglobin, 15.8 g/100 ml; reticulocyte count, 4.5%; serum indirect bilirubin, 4.9 mg/100 ml; 51Cr-labeled red cell half-life, 12 days; red cells showed moderate stomatocytosis. His red cell ADA activity showed 40-fold increase while that of the mother showed 4-fold increase. The mother was hematologically normal. The father had a normal enzyme activity. The proband and the mother showed slightly high serum uric acid levels. The proband's red cell showed: ATP, 628 nmoles/ml (normal, 1,010--1,550); adenine nucleotide pool, 46% of the normal mean; 2,3-diphosphoglycerate content, 3,782 nmoles/ml (normal 4,170--5,300); increased oxygen affinity of hemoglobin, P50 of intact erythrocytes being 21.8 mmHg (normal, 24.1--26.1). Red cell glycolytic intermediates in the proband were low in general, and the rate of lactate production was low. Kinetic studies using crude hemolysate revealed a normal Km for adenosine, normal electrophoretic mobility but slightly abnormal pH curve and slightly low utilization of 2-deoxyadenosine. The ADA activity of lymphocytes was nearly normal.

Enteroaggregative, Shiga Toxin-Producing Escherichia coli O111:H2 Associated with an Outbreak of Hemolytic-Uremic Syndrome

PubMed Central

Morabito, Stefano; Karch, Helge; Mariani-Kurkdjian, Patrizia; Schmidt, Herbert; Minelli, Fabio; Bingen, Edouard; Caprioli, Alfredo

1998-01-01

Shiga toxin-producing Escherichia coli O111:H2 strains from an outbreak of hemolytic-uremic syndrome showed aggregative adhesion to HEp-2 cells and harbored large plasmids which hybridized with the enteroaggregative E. coli probe PCVD432. These strains present a novel combination of virulence factors and might be as pathogenic to humans as the classic enterohemorrhagic E. coli. PMID:9508328

Red cell exchange to mitigate a delayed hemolytic transfusion reaction in a patient transfused with incompatible red blood cells.

PubMed

Irani, Mehraboon S; Karafin, Matthew S; Ernster, Luke

2017-02-01

A red cell exchange was performed to prevent a potentially fatal hemolytic transfusion reaction in a patient with anti-e who was transfused with e-antigen unscreened red blood cells during liver transplant surgery. A 64-year-old woman with cirrhosis due to hepatitis C was scheduled to receive a liver transplant. She had a previously documented anti-e, an antibody to the Rh(e)-antigen that is known to cause delayed hemolytic transfusion reactions. Pre-operatively and intra-operatively, she had massive hemorrhage which required transfusion of 34 e-antigen unscreened red blood cells (RBCs) most of which were incompatible. The hemoglobin dropped from 9.1 g/dL on post-operative day (POD)1 to 6.6 g/dL on POD6, with no evidence of blood loss. The bilirubin also increased from 5.0 mg/dL on POD 1 to 11.0 mg/dL on POD 6. As she was also becoming more hemodynamically unstable, a red cell exchange with 10 units of e-negative RBCs was performed on POD 6. She improved clinically and was extubated the following day. A few residual transfused e-positive red cells were detected after the red cell exchange until POD 13. This case illustrates how a red cell exchange can mitigate the potentially harmful effects of a delayed hemolytic transfusion reaction caused by red cell antibodies. With massive intraoperative blood loss it may not be possible to have antigen-negative RBCs immediately available, particularly for the e-antigen, which is present in 98% of the donor population. The ability to perform such a procedure may be life-saving in such patients. J. Clin. Apheresis 32:59-61, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Engineered M13 bacteriophage nanocarriers for intracellular delivery of exogenous proteins to human prostate cancer cells.

PubMed

DePorter, Sandra M; McNaughton, Brian R

2014-09-17

The size, well-defined structure, and relatively high folding energies of most proteins allow them to recognize disease-relevant receptors that present a challenge to small molecule reagents. While multiple challenges must be overcome in order to fully exploit the use of protein reagents in basic research and medicine, perhaps the greatest challenge is their intracellular delivery to a particular diseased cell. Here, we describe the genetic and enzymatic manipulation of prostate cancer cell-penetrating M13 bacteriophage to generate nanocarriers for the intracellular delivery of functional exogenous proteins to a human prostate cancer cell line.

Facile one-pot multicomponent synthesis and molecular docking studies of steroidal oxazole/thiazole derivatives with effective antimicrobial, antibiofilm and hemolytic properties.

PubMed

Ansari, Anam; Ali, Abad; Asif, Mohd; Rauf, Mohd Ahmar; Owais, Mohammad; Shamsuzzaman

2018-06-01

A series of steroidal oxazole and thiazole derivatives have been synthesized employing thiosemicarbazide/semicarbazide hydrochloride and ethyl 2-chloroacetoacetate with a simple and facile one-pot multicomponent reaction pathway. The antimicrobial activity of newly synthesized compounds were evaluated against four bacterial strains namely Gram-negative (Escherichia coliand Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) in addition to pathogenic fungi (Candida albicans and Cryptococcus neoformans). Bioactivity assay manifested that most of the compounds exhibited good antimicrobial activity. To provide additional insight into antimicrobial activity, the compounds were also tested for their antibiofilm activity against S. aureus biofilm. Moreover, molecular docking study shows binding of compounds with amino acid residues of DNA gyrase and glucosamine-6-phosphate synthase (promising antimicrobial target) through hydrogen bonding interactions. Hemolytic activity have been also investigated to ascertain the effect of compounds over RBC lysis and results indicate good prospects for biocompatibility. The expedient synthesis of steroidal heterocycles, effective antibacterial and antifungal behavior against various clinically relevant human pathogens, promising biocompatibility offer opportunities for further modification and potential applications as therapeutic agents. Copyright © 2018 Elsevier Inc. All rights reserved.

Life-threatening autoimmune warm hemolytic anemia following treatment for multiple sclerosis with alemtuzumab.

PubMed

Meunier, Benoit; Rico, Audrey; Seguier, Julie; Boutiere, Clemence; Ebbo, Mikael; Harle, Jean Robert; Schleinitz, Nicolas; Pelletier, Jean

2018-05-01

Alemtuzumab is a humanized monoclonal antibody directed at CD52 approved as a disease-modifying therapy for relapsing forms of multiple sclerosis (MS). To describe a case of a life-threatening autoimmune anemia occurring after a first course of alemtuzumab for relapsing-remitting MS in a 28-year-old male. Case report. A 28-year-old male developed a life-threatening autoimmune anemia occurring 11 months after first alemtuzumab course. We report the third case of autoimmune hemolytic anemia following treatment with alemtuzumab in a young MS patient. Due to the severity of this adverse event, neurologists using this treatment should be alert.

Resveratrol liposomes and lipid nanocarriers: Comparison of characteristics and inducing browning of white adipocytes

PubMed Central

Zu, Yujiao; Overby, Haley; Ren, Guofeng; Fan, Zhaoyang; Zhao, Ling; Wang, Shu

2018-01-01

Trans -resveratrol (R) has a potential to increase energy expenditure via inducing browning in white adipose tissue. However, its low levels of aqueous solubility, stability, and poor bioavailability limit its application. We have successfully synthesized biocompatible, and biodegradable R encapsulated lipid nanocarriers (R-nano), and R encapsulated liposomes (R-lipo). The mean particle size of R-nano and R-lipo were 140 nm and 110 nm, respectively, and their polydispersity index values were less than 0.2. Nanoen-capsulation significantly increased aqueous solubility and enhanced chemical stability of R, especially at 37 °C. R-lipo had higher physical and chemical stability than R-nano while R-nano had more prolonged release than R-lipo. Both R-nano and R-lipo increased cellular R content in 3T3-L1 cells. Both R-nano and R-lipo dose-dependently induced uncoupling protein 1 (UCP1) mRNA expression and decreased white specific marker insulin growth factor binding protein 3 expression under isoproterenol (ISO)-stimulated conditions. At the low dose (5 μM), nanoencapsulated compared to native R enhanced UCP1 and beige marker CD137 expression under ISO-stimulated conditions. Compared to R-nano, R-lipo had better biological activity, possibly due to its higher physical and chemical stability at the room and body temperature. Taken together, our study demonstrates that nanoencapsulation increased R’s aqueous solubility and stability, which led to enhanced browning of white adipocytes. Even though both R-lipo and R-nano increased R’s browning activities, their differential characteristics need to be considered in obesity treatment. PMID:29433059

Phosphatidylserine exposure and red cell viability in red cell aging and in hemolytic anemia.

PubMed

Boas, F E; Forman, L; Beutler, E

1998-03-17

Phosphatidylserine (PS) normally localizes to the inner leaflet of cell membranes but becomes exposed in abnormal or apoptotic cells, signaling macrophages to ingest them. Along similar lines, it seemed possible that the removal of red cells from circulation because of normal aging or in hemolytic anemias might be triggered by PS exposure. To investigate the role of PS exposure in normal red cell aging, we used N-hydroxysuccinimide-biotin to tag rabbit red cells in vivo, then used phycoerythrin-streptavidin to label the biotinylated cells, and annexin V-fluorescein isothiocyanate (FITC) to detect the exposed PS. Flow cytometric analysis of these cells drawn at 10-day intervals up to 70 days after biotinylation indicated that older, biotinylated cells expose more PS. Furthermore, our data match a simple model of red cell senescence that assumes both an age-dependent destruction of senescent red cells preceded by several hours of PS exposure and a random destruction of red cells without PS exposure. By using this model, we demonstrated that the exposure of PS parallels the rate at which biotinylated red cells are removed from circulation. On the other hand, using an annexin V-FITC label and flow cytometry demonstrates that exposed PS does not cause the reduced red cell life span of patients with hemolytic anemia, with the possible exception of those with unstable hemoglobins or sickle cell anemia. Thus, in some cases PS exposure on the cell surface may signal the removal of red cells from circulation, but in other cases some other signal must trigger the sequestration of cells.

Hemolytic anemia in alcoholic liver disease: Zieve syndrome: A case report and literature review.

PubMed

Liu, Miao-Xia; Wen, Xiao-Yu; Leung, Ying-Kit; Zheng, Yi-Jie; Jin, Mei-Shan; Jin, Qing-Long; Niu, Jun-Qi

2017-11-01

Zieve syndrome, a rarely reported disease resulting from alcohol abuse, consists of a triad of symptoms: hemolytic anemia, cholestatic jaundice, and transient hyperlipidemia. It is largely under-recognized and under-reported, possibly because of unawareness of the condition by physicians. Here, we report a case of Zieve syndrome managed at the Jilin University First Bethune Hospital. A 30-year-old Chinese woman presented with a 4-month history of fatigue, yellowish discoloration of the eyes, and tea-colored urine. She had been a heavy drinker for 2 years prior to onset of the disease with an average daily alcohol intake of 60 g/d and more than 80 g/d for the previous 6 months. The diagnosis of Zieve syndrome was confirmed based on hemolysis and cholestatic jaundice secondary to alcoholic liver disease and heavy drinking. Bone marrow biopsy and liver biopsy both supported the diagnosis. We treated her with abstinence from alcohol and supportive therapy. The patient was discharged 14 days after admission with an improvement in symptoms, which continued to subside during the 2-month follow-up period. Doctors confronted with hemolysis in a patient with alcoholic liver disease should be aware of the under-reported Zieve syndrome. Recognition of this syndrome could help doctors avoid unnecessary invasive procedures and emphasize the importance of alcohol abstinence as the mainstay of management. Glucocorticoids may not be useful in treating hemolytic anemia in Zieve syndrome. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Synthesis of 2-{(5-phenyl-1,3,4-Oxadiazol-2-yl)sulfanyl}-N-substituted acetamides as potential antimicrobial and hemolytic agents.

PubMed

Rehman, Aziz-ur; Abbasi, Muhammad Athar; Siddiqui, Sabahat Zahra; Ahmad, Irshad; Shahid, Muhammad; Subhani, Zinayyera

2016-05-01

A new series of N-substituted derivatives of 2-{(5-phenyl-1,3,4-Oxadiazol-2-yl)sulfanyl}acetamides was synthesized. The synthesis was carried out by converting benzoic acid (1) into ethyl benzoate (2), benzohydrazide (3) and then 5-pheny-1,3,4-Oxadiazol-2-thiol (4) step by st0ep. The target compounds 6a-p were synthesized by reaction of compound 4 with equimolar ratios of different N-alkyl/aryl substituted 2-bromoacetamide (5a-p) in the presence of DMF and sodium hydride (NaH). The spectral (EI-MS, IR, (1)H-NMR) characterization of all the synthesized compounds reveal their successful synthesis. The compounds were also screened for antimicrobial & hemolytic activity and most of them were found to be active against the selected microbial species at variable extent relative to reference standards. But 6h was the most active against the selected panel of microbes. This series showed less toxicity and may be considered for further biological screening and application trial except 6m, possessing higher cytotoxicity.

Lipid prodrug nanocarriers in cancer therapy.

PubMed

Mura, Simona; Bui, Duc Trung; Couvreur, Patrick; Nicolas, Julien

2015-06-28

Application of nanotechnology in the medical field (i.e., nanomedicine) plays an important role in the development of novel drug delivery methods. Nanoscale drug delivery systems can indeed be customized with specific functionalities in order to improve the efficacy of the treatments. However, despite the progresses of the last decades, nanomedicines still face important obstacles related to: (i) the physico-chemical properties of the drug moieties which may reduce the total amount of loaded drug; (ii) the rapid and uncontrolled release (i.e., burst release) of the encapsulated drug after administration and (iii) the instability of the drug in biological media where a fast transformation into inactive metabolites can occur. As an alternative strategy to alleviate these drawbacks, the prodrug approach has found wide application. The covalent modification of a drug molecule into an inactive precursor from which the drug will be freed after administration offers several benefits such as: (i) a sustained drug release (mediated by chemical or enzymatic hydrolysis of the linkage between the drug-moiety and its promoiety); (ii) an increase of the drug chemical stability and solubility and, (iii) a reduced toxicity before the metabolization occurs. Lipids have been widely used as building blocks for the design of various prodrugs. Interestingly enough, these lipid-derivatized drugs can be delivered through a nanoparticulate form due to their ability to self-assemble and/or to be incorporated into lipid/polymer matrices. Among the several prodrugs developed so far, this review will focus on the main achievements in the field of lipid-based prodrug nanocarriers designed to improve the efficacy of anticancer drugs. Gemcitabine (Pubchem CID: 60750); 5-fluorouracil (Pubchem CID: 3385); Doxorubicin (Pubchem CID: 31703); Docetaxel (Pubchem CID: 148124); Methotrexate (Pubchem CID: 126941); Paclitaxel (Pubchem CID: 36314). Copyright © 2015 Elsevier B.V. All rights reserved.

Antitubercular Nanocarrier Combination Therapy: Formulation Strategies and in Vitro Efficacy for Rifampicin and SQ641

PubMed Central

2015-01-01

Tuberculosis (TB) remains a major global health concern, and new therapies are needed to overcome the problems associated with dosing frequency, patient compliance, and drug resistance. To reduce side effects associated with systemic drug distribution and improve drug concentration at the target site, stable therapeutic nanocarriers (NCs) were prepared and evaluated for efficacy in vitro in Mycobacterium tuberculosis-infected macrophages. Rifampicin (RIF), a current, broad-spectrum antibiotic used in TB therapy, was conjugated by degradable ester bonds to form hydrophobic prodrugs. NCs encapsulating various ratios of nonconjugated RIF and the prodrugs showed the potential ability to rapidly deliver and knockdown intracellular M. tuberculosis by nonconjugated RIF and to obtain sustained release of RIF by hydrolysis of the RIF prodrug. NCs of the novel antibiotic SQ641 and a combination NC with cyclosporine A were formed by flash nanoprecipitation. Delivery of SQ641 in NC form resulted in significantly improved activity compared to that of the free drug against intracellular M. tuberculosis. A NC formulation with a three-compound combination of SQ641, cyclosporine A, and vitamin E inhibited intracellular replication of M. tuberculosis significantly better than SQ641 alone or isoniazid, a current first-line anti-TB drug. PMID:25811733

Neutralization, by a monospecific Bothrops lanceolatus antivenom, of toxic activities induced by homologous and heterologous Bothírops snake venoms.

PubMed

Bogarín, G; Romero, M; Rojas, G; Lutsch, C; Casadamont, M; Lang, J; Otero, R; Gutiérrez, J M

1999-03-01

A monospecific Bothrops lanceolatus antivenom, currently used in Martinique, was tested for its efficacy in the neutralization of several toxic and enzymatic activities of the venoms of B. lanceolatus, B. atrox and B. asper. When tested by the i.p. route in mice, B. lanceolatus venom had an LD50 of 12.8 microg/g. In addition, it induced local tissue damage (hemorrhage, edema and myotoxicity) and showed indirect hemolytic activity, but was devoid of coagulant effect on human plasma in vitro and of defibrinating activity in mice. Antivenom was fully effective in the neutralization of lethal, hemorrhagic, edema-forming, myotoxic and indirect hemolytic effects of B. lanceolatus venom in assays involving preincubation of venom and antivenom. When tested against the venoms of B. asper and B. atrox, the antivenom completely neutralized the lethal, hemorrhagic, myotoxic and indirect hemolytic effects, and was partially effective in neutralizing edema-forming activity. In contrast, the antivenom was ineffective in the neutralization of in vitro coagulant and in vivo defibrinating effects induced by these two venoms.

Evaluation of brain targeting and mucosal integrity of nasally administrated nanostructured carriers of a CNS active drug, clonazepam.

PubMed

Abdel-Bar, Hend Mohamed; Abdel-Reheem, Amal Youssef; Awad, Gehanne Abdel Samie; Mortada, Nahed Daoud

2013-01-01

The aim of the study was to target clonazepam, a CNS active drug, to the brain through the non-invasive intranasal (in) route using of nanocarriers with proven safety in clonazepam nanocarriers were prepared by mixing isopropyl myristate, Tween 80, Cremophor EL or lecithin, polyethylene glycol 200, propylene glycol or ethanol in different ratios with water. in-vitro characterization of the nanocarriers was done by various methods including: polarized light microscopy, particle size determination, viscosity measurements and drug release studies. in-vivo study comparing intranasal and intravenous administration was performed. The drug targeting efficiency (DTE %) and direct nose to brain transport percentage (DTP %) were calculated and nasal integrity assessment was carried out. The obtained formulae had particle size below 100 nm favoring rapid direct nose to brain transport and the time for 100% drug release (T100%) depended on systems composition. Plasma Tmax of clonazepam nanostructured carriers varied from 10-30 min., while their brain Tmax did not exceed 10 min, in comparison with 30 min for iv solution. Although there was no significant difference (p>0.05) between the plasma AUC0-∞ of the different tested nanocarriers and intravenous one, the increase in brain AUC 0 -∞ of different nasal formulations in comparison to that of iv administration (3.6 -7.2 fold) confirms direct nose to brain transport via olfactory region. Furthermore, DTE and DTP% confirmed brain targeting of clonazepam following intranasal administration. The results confirmed that intranasal nanocarriers were proved to be safe alternative for iv clonazepam delivery with rapid nose to brain transport.

Evaluation of theranostic nanocarriers for near-infrared imaging and photodynamic therapy on human prostate cancer cells.

PubMed

Leandro, Fernanda Z; Martins, Júlia; Fontes, Aparecida M; Tedesco, Antonio C

2017-06-01

This paper evaluates how effectively chloroaluminum phthalocyanine (ClAlPc) entrapped in colloidal nanocarriers, such as nanocapsule (NC) and nanoemulsion (NE), induces photodamage in human prostate cancer cells (LNCaP) during photodynamic therapy (PDT). The MTT cell viability assay showed that both ClAlPc-NC and ClAlPc-NE induced phototoxicity and efficiently killed LNCaP cells at low ClAlPc-NC and ClAlPc-NE concentrations (0.3μgmL -1 ) as well as under low light doses of 4Jcm -2 and 7Jcm -2 , respectively, upon PDT with a 670-nm diode laser line. Confocal imaging studies indicated that ClAlPc-NC and ClAlPc-NE were preferentially localized in the perinuclear region of LNCaP cells both in the dark and upon irradiation with laser light. After PDT treatment, ClAlPc-NC-treated LNCaP cells exhibited a higher green fluorescence signal, possibly due to the larger shrinkage of the actin cytoskeleton, compared to ClAlPc-NE-treated LNCaP cells. Additionally, ClAlPc-NC or ClAlPc-NE and mitochondria showed a relatively high co-localization level. The cellular morphology did not change in the dark, but confocal micrographs recorded after PDT revealed that LNCaP cells treated with ClAlPc-NC or ClAlPc-NE underwent morphological alterations. Our preliminary in vitro studies reinforced the hypothesis that biocompatible theranostic ClAlPc-loaded nanocarriers could act as an attractive photosensitizer system in PDT and could serve as an interesting molecular probe for the early diagnosis of prostate cancer and other carcinomas. Copyright © 2017 Elsevier B.V. All rights reserved.

Doxorubicin loaded dual pH- and thermo-responsive magnetic nanocarrier for combined magnetic hyperthermia and targeted controlled drug delivery applications

NASA Astrophysics Data System (ADS)

Hervault, Aziliz; Dunn, Alexander E.; Lim, May; Boyer, Cyrille; Mott, Derrick; Maenosono, Shinya; Thanh, Nguyen T. K.

2016-06-01

Magnetic nanocarriers have attracted increasing attention for multimodal cancer therapy due to the possibility to deliver heat and drugs locally. The present study reports the development of magnetic nanocomposites (MNCs) made of an iron oxide core and a pH- and thermo-responsive polymer shell, that can be used as both hyperthermic agent and drug carrier. The conjugation of anticancer drug doxorubicin (DOX) to the pH- and thermo-responsive MNCs via acid-cleavable imine linker provides advanced features for the targeted delivery of DOX molecules via the combination of magnetic targeting, and dual pH- and thermo-responsive behaviour which offers spatial and temporal control over the release of DOX. The iron oxide cores exhibit a superparamagnetic behaviour with a saturation magnetization around 70 emu g-1. The MNCs contained 8.1 wt% of polymer and exhibit good heating properties in an alternating magnetic field. The drug release experiments confirmed that only a small amount of DOX was released at room temperature and physiological pH, while the highest drug release of 85.2% was obtained after 48 h at acidic tumour pH under hyperthermia conditions (50 °C). The drug release kinetic followed Korsmeyer-Peppas model and displayed Fickian diffusion mechanism. From the results obtained it can be concluded that this smart magnetic nanocarrier is promising for applications in multi-modal cancer therapy, to target and efficiently deliver heat and drug specifically to the tumour.Magnetic nanocarriers have attracted increasing attention for multimodal cancer therapy due to the possibility to deliver heat and drugs locally. The present study reports the development of magnetic nanocomposites (MNCs) made of an iron oxide core and a pH- and thermo-responsive polymer shell, that can be used as both hyperthermic agent and drug carrier. The conjugation of anticancer drug doxorubicin (DOX) to the pH- and thermo-responsive MNCs via acid-cleavable imine linker provides advanced

Locoregional Confinement and Major Clinical Benefit of 188Re-Loaded CXCR4-Targeted Nanocarriers in an Orthotopic Human to Mouse Model of Glioblastoma.

PubMed

Séhédic, Delphine; Chourpa, Igor; Tétaud, Clément; Griveau, Audrey; Loussouarn, Claire; Avril, Sylvie; Legendre, Claire; Lepareur, Nicolas; Wion, Didier; Hindré, François; Davodeau, François; Garcion, Emmanuel

2017-01-01

Gold standard beam radiation for glioblastoma (GBM) treatment is challenged by resistance phenomena occurring in cellular populations well prepared to survive or to repair damage caused by radiation. Among signals that have been linked with radio-resistance, the SDF1/CXCR4 axis, associated with cancer stem-like cell, may be an opportune target. To avoid the problem of systemic toxicity and blood-brain barrier crossing, the relevance and efficacy of an original system of local brain internal radiation therapy combining a radiopharmaceutical with an immuno-nanoparticle was investigated. The nanocarrier combined lipophilic thiobenzoate complexes of rhenium-188 loaded in the core of a lipid nanocapsule (LNC 188 Re) with a function-blocking antibody, 12G5 directed at the CXCR4, on its surface. The efficiency of 12G5-LNC 188 Re was investigated in an orthotopic and xenogenic GBM model of CXCR4-positive U87MG cells implanted in the striatum of Scid mice. We demonstrated that 12G5-LNC 188 Re single infusion treatment by convection-enhanced delivery resulted in a major clinical improvement in median survival that was accompanied by locoregional effects on tumor development including hypovascularization and stimulation of the recruitment of bone marrow derived CD11b- or CD68-positive cells as confirmed by immunohistochemistry analysis. Interestingly, thorough analysis by spectral imaging in a chimeric U87MG GBM model containing CXCR4-positive/red fluorescent protein (RFP)-positive- and CXCR4-negative/RFP-negative-GBM cells revealed greater confinement of DiD-labeled 12G5-LNCs than control IgG2a-LNCs in RFP compartments. Main conclusion: These findings on locoregional impact and targeting of disseminated cancer cells in tumor margins suggest that intracerebral active targeting of nanocarriers loaded with radiopharmaceuticals may have considerable benefits in clinical applications.

Locoregional Confinement and Major Clinical Benefit of 188Re-Loaded CXCR4-Targeted Nanocarriers in an Orthotopic Human to Mouse Model of Glioblastoma

PubMed Central

Séhédic, Delphine; Chourpa, Igor; Tétaud, Clément; Griveau, Audrey; Loussouarn, Claire; Avril, Sylvie; Legendre, Claire; Lepareur, Nicolas; Wion, Didier; Hindré, François; Davodeau, François; Garcion, Emmanuel

2017-01-01

Purpose: Gold standard beam radiation for glioblastoma (GBM) treatment is challenged by resistance phenomena occurring in cellular populations well prepared to survive or to repair damage caused by radiation. Among signals that have been linked with radio-resistance, the SDF1/CXCR4 axis, associated with cancer stem-like cell, may be an opportune target. To avoid the problem of systemic toxicity and blood-brain barrier crossing, the relevance and efficacy of an original system of local brain internal radiation therapy combining a radiopharmaceutical with an immuno-nanoparticle was investigated. Experiment design: The nanocarrier combined lipophilic thiobenzoate complexes of rhenium-188 loaded in the core of a lipid nanocapsule (LNC188Re) with a function-blocking antibody, 12G5 directed at the CXCR4, on its surface. The efficiency of 12G5-LNC188Re was investigated in an orthotopic and xenogenic GBM model of CXCR4-positive U87MG cells implanted in the striatum of Scid mice. Results: We demonstrated that 12G5-LNC188Re single infusion treatment by convection-enhanced delivery resulted in a major clinical improvement in median survival that was accompanied by locoregional effects on tumor development including hypovascularization and stimulation of the recruitment of bone marrow derived CD11b- or CD68-positive cells as confirmed by immunohistochemistry analysis. Interestingly, thorough analysis by spectral imaging in a chimeric U87MG GBM model containing CXCR4-positive/red fluorescent protein (RFP)-positive- and CXCR4-negative/RFP-negative-GBM cells revealed greater confinement of DiD-labeled 12G5-LNCs than control IgG2a-LNCs in RFP compartments. Main conclusion: These findings on locoregional impact and targeting of disseminated cancer cells in tumor margins suggest that intracerebral active targeting of nanocarriers loaded with radiopharmaceuticals may have considerable benefits in clinical applications. PMID:29158842

The potential of magneto-electric nanocarriers for drug delivery

PubMed Central

Kaushik, Ajeet; Jayant, Rahul Dev; Sagar, Vidya; Nair, Madhavan

2015-01-01

Introduction The development and design of personalized nanomedicine for better health quality is receiving great attention. In order to deliver and release a therapeutic concentration at the target site, novel nanocarriers (NCs) were designed, for example, magneto-electric (ME) which possess ideal properties of high drug loading, site-specificity and precise on-demand controlled drug delivery. Areas covered This review explores the potential of ME-NCs for on-demand and site-specific drug delivery and release for personalized therapeutics. The main features including effect of magnetism, improvement in drug loading, drug transport across blood-brain barriers and on-demand controlled release are also discussed. The future directions and possible impacts on upcoming nanomedicine are highlighted. Expert opinion Numerous reports suggest that there is an urgent need to explore novel NC formulations for safe and targeted drug delivery and release at specific disease sites. The challenges of formulation lie in the development of NCs that improve biocompatibility and surface modifications for optimum drug loading/preservation/transmigration and tailoring of electrical–magnetic properties for on-demand drug release. Thus, the development of novel NCs is anticipated to overcome the problems of targeted delivery of therapeutic agents with desired precision that may lead to better patient compliance. PMID:24986772

Stability of plant virus-based nanocarriers in gastrointestinal fluids† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7nr07182e

PubMed Central

Evans, David J.; Baldelli Bombelli, Francesca; Lomonossoff, George P.

2018-01-01

Cowpea mosaic virus (CPMV) is a plant virus which is being extensively investigated as a drug delivery and vaccine nanocarrier for parenteral administration. However, to date little is known about the suitability of plant-based nanocarriers for oral delivery. In this study, the colloidal (i.e. aggregation), physical (i.e. denaturation) and chemical (i.e. digestion of the polypeptides) stability of CPMV and its empty virus-like particles (eVLPs) in conditions resembling the gastrointestinal fluids were evaluated. The nanoparticles were incubated in various simulated gastric and intestinal fluids and in pig gastric and intestinal fluids. CPMV and eVLPs had similar stabilities. In simulated gastric media, they were stable at pH ≥ 2.5. At lower pH destabilisation of the particle structure occurred, which, in turn, rendered the polypeptides extremely sensitive to pepsin digestion. However, both CPMV and eVLPs were stable in simulated intestinal fluids, in pig gastric fluids and in pig intestinal fluids. Thus CPMV, despite being a protein-based nanoparticle, was much more resistant to the harsh GI conditions than soluble proteins. Remarkably, both CPMV and eVLPs incubated in pig gastric and intestinal fluids were not subject to protein adsorption, with no formation of a detectable protein corona. The lack of a protein corona on CPMV and eVLP surfaces in GI fluids would imply that, if orally administered, these nanoparticles could maintain their native surface characteristics; thus, their biological interactions would remain predictable and unchanged. In summary, CPMV and eVLPs can be considered promising nanocarriers for applications requiring oral delivery, given their chemical, physical and colloidal stability and lack of protein adsorption from the environment in most of the tested conditions. PMID:29231944

Soluble CD40 Ligand and Oxidative Response Are Reciprocally Stimulated during Shiga Toxin-Associated Hemolytic Uremic Syndrome

PubMed Central

Abrey Recalde, Maria J.; Alvarez, Romina S.; Alberto, Fabiana; Mejias, Maria P.; Ramos, Maria V.; Fernandez Brando, Romina J.; Bruballa, Andrea C.; Exeni, Ramon A.; Alconcher, Laura; Ibarra, Cristina A.; Amaral, María M.; Palermo, Marina S.

2017-01-01

Shiga toxin (Stx), produced by Escherichia coli, is the main pathogenic factor of diarrhea-associated hemolytic uremic syndrome (HUS), which is characterized by the obstruction of renal microvasculature by platelet-fibrin thrombi. It is well known that the oxidative imbalance generated by Stx induces platelet activation, contributing to thrombus formation. Moreover, activated platelets release soluble CD40 ligand (sCD40L), which in turn contributes to oxidative imbalance, triggering the release of reactive oxidative species (ROS) on various cellular types. The aim of this work was to determine if the interaction between the oxidative response and platelet-derived sCD40L, as consequence of Stx-induced endothelium damage, participates in the pathogenic mechanism during HUS. Activated human glomerular endothelial cells (HGEC) by Stx2 induced platelets to adhere to them. Although platelet adhesion did not contribute to endothelial damage, high levels of sCD40L were released to the medium. The release of sCD40L by activated platelets was inhibited by antioxidant treatment. Furthermore, we found increased levels of sCD40L in plasma from HUS patients, which were also able to trigger the respiratory burst in monocytes in a sCD40L-dependent manner. Thus, we concluded that platelet-derived sCD40L and the oxidative response are reciprocally stimulated during Stx2-associated HUS. This process may contribute to the evolution of glomerular occlusion and the microangiopathic lesions. PMID:29068360

Dual-drug nanomedicine with hydrophilic F127-modified magnetic nanocarriers assembled in amphiphilic gelatin for enhanced penetration and drug delivery in deep tumor tissue.

PubMed

Lai, Yen-Ho; Chiang, Chih-Sheng; Kao, Tzu-Hsun; Chen, San-Yuan

2018-01-01

Deep penetration of large-sized drug nanocarriers into tumors is important to improve the efficacy of tumor therapy. In this study, we developed a size-changeable "Trojan Horse" nanocarrier (THNC) composed of paclitaxel (PTX)-loaded Greek soldiers (GSs; ~20 nm) assembled in an amphiphilic gelatin matrix with hydrophilic losartan (LST) added. With amphiphilic gelatin matrix cleavage by matrix metalloproteinase-2, LST showed fast release of up to 60% accumulated drug at 6 h, but a slow release kinetic (~20%) was detected in the PTX from the GSs, indicating that THNCs enable controllable release of LST and PTX drugs for penetration into the tumor tissue. The in vitro cell viability in a 3D tumor spheroid model indicated that the PTX-loaded GSs liberated from THNCs showed deeper penetration as well as higher cytotoxicity, reducing a tumor spheroid to half its original size and collapsing the structure of the tumor microenvironment. The results demonstrate that the THNCs with controlled drug release and deep penetration of magnetic GSs show great potential for cancer therapy.

A targeted and adjuvanted nanocarrier lowers the effective dose of liposomal amphotericin B and enhances adaptive immunity in murine cutaneous leishmaniasis.

PubMed

Daftarian, Pirouz M; Stone, Geoffrey W; Kovalski, Leticia; Kumar, Manoj; Vosoughi, Aram; Urbieta, Maitee; Blackwelder, Pat; Dikici, Emre; Serafini, Paolo; Duffort, Stephanie; Boodoo, Richard; Rodríguez-Cortés, Alhelí; Lemmon, Vance; Deo, Sapna; Alberola, Jordi; Perez, Victor L; Daunert, Sylvia; Ager, Arba L

2013-12-01

Amphotericin B (AmB), the most effective drug against leishmaniasis, has serious toxicity. As Leishmania species are obligate intracellular parasites of antigen presenting cells (APC), an immunopotentiating APC-specific AmB nanocarrier would be ideally suited to reduce the drug dosage and regimen requirements in leishmaniasis treatment. Here, we report a nanocarrier that results in effective treatment shortening of cutaneous leishmaniasis in a mouse model, while also enhancing L. major specific T-cell immune responses in the infected host. We used a Pan-DR-binding epitope (PADRE)-derivatized-dendrimer (PDD), complexed with liposomal amphotericin B (LAmB) in an L. major mouse model and analyzed the therapeutic efficacy of low-dose PDD/LAmB vs full dose LAmB. PDD was shown to escort LAmB to APCs in vivo, enhanced the drug efficacy by 83% and drug APC targeting by 10-fold and significantly reduced parasite burden and toxicity. Fortuitously, the PDD immunopotentiating effect significantly enhanced parasite-specific T-cell responses in immunocompetent infected mice. PDD reduced the effective dose and toxicity of LAmB and resulted in elicitation of strong parasite specific T-cell responses. A reduced effective therapeutic dose was achieved by selective LAmB delivery to APC, bypassing bystander cells, reducing toxicity and inducing antiparasite immunity.

Doxorubicin loaded magnetic polymersomes: theranostic nanocarriers for MR imaging and magneto-chemotherapy.

PubMed

Sanson, Charles; Diou, Odile; Thévenot, Julie; Ibarboure, Emmanuel; Soum, Alain; Brûlet, Annie; Miraux, Sylvain; Thiaudière, Eric; Tan, Sisareuth; Brisson, Alain; Dupuis, Vincent; Sandre, Olivier; Lecommandoux, Sébastien

2011-02-22

Hydrophobically modified maghemite (γ-Fe(2)O(3)) nanoparticles were encapsulated within the membrane of poly(trimethylene carbonate)-b-poly(l-glutamic acid) (PTMC-b-PGA) block copolymer vesicles using a nanoprecipitation process. This formation method gives simple access to highly magnetic nanoparticles (MNPs) (loaded up to 70 wt %) together with good control over the vesicles size (100-400 nm). The simultaneous loading of maghemite nanoparticles and doxorubicin was also achieved by nanoprecipitation. The deformation of the vesicle membrane under an applied magnetic field has been evidenced by small angle neutron scattering. These superparamagnetic hybrid self-assemblies display enhanced contrast properties that open potential applications for magnetic resonance imaging. They can also be guided in a magnetic field gradient. The feasibility of controlled drug release by radio frequency magnetic hyperthermia was demonstrated in the case of encapsulated doxorubicin molecules, showing the viability of the concept of magneto-chemotherapy. These magnetic polymersomes can be used as efficient multifunctional nanocarriers for combined therapy and imaging.

Evaluation of boron nitride nanotubes and hexagonal boron nitrides as nanocarriers for cancer drugs.

PubMed

Emanet, Melis; Şen, Özlem; Çulha, Mustafa

2017-04-01

Boron nitride nanotubes (BNNTs) and hexagonal boron nitrides (hBNs) are novel nanostructures with high mechanical strengths, large surface areas and excellent biocompatibilities. Here, the potential use of BNNTs and hBNs as nanocarriers was comparatively investigated for use with cancer drugs. Doxorubicin (Dox) and folate are used as model drugs and targeting agents, respectively. The obtained results indicate that BNNTs have about a threefold higher Dox loading capacity than hBNs. It was also found that cellular uptake of folate-Dox-BNNTs was much higher when compared with Dox-BNNTs for HeLa cells, due to the presence of folate receptors on the cell surface, leading to increased cancer cell death. In summary, folate and Dox conjugated BNNTs are promising agents in nanomedicine and may have potential drug delivery applications.

Hemolytic Potential of Tafenoquine in Female Volunteers Heterozygous for Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency (G6PD Mahidol Variant) versus G6PD-Normal Volunteers.

PubMed

Rueangweerayut, Ronnatrai; Bancone, Germana; Harrell, Emma J; Beelen, Andrew P; Kongpatanakul, Supornchai; Möhrle, Jörg J; Rousell, Vicki; Mohamed, Khadeeja; Qureshi, Ammar; Narayan, Sushma; Yubon, Nushara; Miller, Ann; Nosten, François H; Luzzatto, Lucio; Duparc, Stephan; Kleim, Jörg-Peter; Green, Justin A

2017-09-01

Tafenoquine is an 8-aminoquinoline under investigation for the prevention of relapse in Plasmodium vivax malaria. This open-label, dose-escalation study assessed quantitatively the hemolytic risk with tafenoquine in female healthy volunteers heterozygous for the Mahidol 487A glucose-6-phosphate dehydrogenase (G6PD)-deficient variant versus G6PD-normal females, and with reference to primaquine. Six G6PD-heterozygous subjects (G6PD enzyme activity 40-60% of normal) and six G6PD-normal subjects per treatment group received single-dose tafenoquine (100, 200, or 300 mg) or primaquine (15 mg × 14 days). All participants had pretreatment hemoglobin levels ≥ 12.0 g/dL. Tafenoquine dose escalation stopped when hemoglobin decreased by ≥ 2.5 g/dL (or hematocrit decline ≥ 7.5%) versus pretreatment values in ≥ 3/6 subjects. A dose-response was evident in G6PD-heterozygous subjects ( N = 15) receiving tafenoquine for the maximum decrease in hemoglobin versus pretreatment values. Hemoglobin declines were similar for tafenoquine 300 mg (-2.65 to -2.95 g/dL [ N = 3]) and primaquine (-1.25 to -3.0 g/dL [ N = 5]). Two further cohorts of G6PD-heterozygous subjects with G6PD enzyme levels 61-80% ( N = 2) and > 80% ( N = 5) of the site median normal received tafenoquine 200 mg; hemolysis was less pronounced at higher G6PD enzyme activities. Tafenoquine hemolytic potential was dose dependent, and hemolysis was greater in G6PD-heterozygous females with lower G6PD enzyme activity levels. Single-dose tafenoquine 300 mg did not appear to increase the severity of hemolysis versus primaquine 15 mg × 14 days.

Hemolytic Potential of Tafenoquine in Female Volunteers Heterozygous for Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency (G6PD Mahidol Variant) versus G6PD-Normal Volunteers

PubMed Central

Rueangweerayut, Ronnatrai; Bancone, Germana; Harrell, Emma J.; Beelen, Andrew P.; Kongpatanakul, Supornchai; Möhrle, Jörg J.; Rousell, Vicki; Mohamed, Khadeeja; Qureshi, Ammar; Narayan, Sushma; Yubon, Nushara; Miller, Ann; Nosten, François H.; Luzzatto, Lucio; Duparc, Stephan; Kleim, Jörg-Peter; Green, Justin A.

2017-01-01

Abstract. Tafenoquine is an 8-aminoquinoline under investigation for the prevention of relapse in Plasmodium vivax malaria. This open-label, dose-escalation study assessed quantitatively the hemolytic risk with tafenoquine in female healthy volunteers heterozygous for the Mahidol487A glucose-6-phosphate dehydrogenase (G6PD)-deficient variant versus G6PD-normal females, and with reference to primaquine. Six G6PD-heterozygous subjects (G6PD enzyme activity 40–60% of normal) and six G6PD-normal subjects per treatment group received single-dose tafenoquine (100, 200, or 300 mg) or primaquine (15 mg × 14 days). All participants had pretreatment hemoglobin levels ≥ 12.0 g/dL. Tafenoquine dose escalation stopped when hemoglobin decreased by ≥ 2.5 g/dL (or hematocrit decline ≥ 7.5%) versus pretreatment values in ≥ 3/6 subjects. A dose–response was evident in G6PD-heterozygous subjects (N = 15) receiving tafenoquine for the maximum decrease in hemoglobin versus pretreatment values. Hemoglobin declines were similar for tafenoquine 300 mg (−2.65 to −2.95 g/dL [N = 3]) and primaquine (−1.25 to −3.0 g/dL [N = 5]). Two further cohorts of G6PD-heterozygous subjects with G6PD enzyme levels 61–80% (N = 2) and > 80% (N = 5) of the site median normal received tafenoquine 200 mg; hemolysis was less pronounced at higher G6PD enzyme activities. Tafenoquine hemolytic potential was dose dependent, and hemolysis was greater in G6PD-heterozygous females with lower G6PD enzyme activity levels. Single-dose tafenoquine 300 mg did not appear to increase the severity of hemolysis versus primaquine 15 mg × 14 days. PMID:28749773

An Intestinal "Transformers"-like Nanocarrier System for Enhancing the Oral Bioavailability of Poorly Water-Soluble Drugs.

PubMed

Chuang, Er-Yuan; Lin, Kun-Ju; Huang, Tring-Yo; Chen, Hsin-Lung; Miao, Yang-Bao; Lin, Po-Yen; Chen, Chiung-Tong; Juang, Jyuhn-Huarng; Sung, Hsing-Wen

2018-06-06

Increasing the intestinal dissolution of orally administered poorly water-soluble drugs that have poor oral bioavailability to a therapeutically effective level has long been an elusive goal. In this work, an approach that can greatly enhance the oral bioavailability of a poorly water-soluble drug such as curcumin (CUR) is developed, using a "Transformers"-like nanocarrier system (TLNS) that can self-emulsify the drug molecules in the intestinal lumen to form nanoemulsions. Owing to its known anti-inflammation activity, the use of CUR in treating pancreatitis is evaluated herein. Structural changes of the TLNS in the intestinal environment to form the CUR-laden nanoemulsions are confirmed in vitro. The therapeutic efficacy of this TLNS is evaluated in rats with experimentally induced acute pancreatitis (AP). Notably, the CUR-laden nanoemulsions that are obtained using the proposed TLNS can passively target intestinal M cells, in which they are transcytosed and then transported into the pancreatic tissues via the intestinal lymphatic system. The pancreases in rats that are treated with the TLNS yield approximately 12 times stronger CUR signals than their counterparts receiving free CUR, potentially improving the recovery of AP. These findings demonstrate that the proposed TLNS can markedly increase the intestinal drug dissolution, making oral delivery a favorable noninvasive means of administering poorly water-soluble drugs.

On the intracellular release mechanism of hydrophobic cargo and its relation to the biodegradation behavior of mesoporous silica nanocarriers.

PubMed

von Haartman, Eva; Lindberg, Desiré; Prabhakar, Neeraj; Rosenholm, Jessica M

2016-12-01

The intracellular release mechanism of hydrophobic molecules from surface-functionalized mesoporous silica nanoparticles was studied in relation to the biodegradation behavior of the nanocarrier, with the purpose of determining the dominant release mechanism for the studied drug delivery system. To be able to follow the real-time intracellular release, a hydrophobic fluorescent dye was used as model drug molecule. The in vitro release of the dye was investigated under varying conditions in terms of pH, polarity, protein and lipid content, presence of hydrophobic structures and ultimately, in live cancer cells. Results of investigating the drug delivery system show that the degradation and drug release mechanisms display a clear interdependency in simple aqueous solvents. In pure aqueous media, the cargo release was primarily dependent on the degradation of the nanocarrier, while in complex media, mimicking intracellular conditions, the physicochemical properties of the cargo molecule itself and its interaction with the carrier and/or surrounding media were found to be the main release-governing factors. Since the material degradation was retarded upon loading with hydrophobic guest molecules, the cargo could be efficiently delivered into live cancer cells and released intracellularly without pronounced premature release under extracellular conditions. From a rational design point of view, pinpointing the interdependency between these two processes can be of paramount importance considering future applications and fundamental understanding of the drug delivery system. Copyright © 2016 Elsevier B.V. All rights reserved.

Specific internalization and synergistic anticancer effect of docetaxel-encapsulated chitosan-modified polymeric nanocarriers: a novel approach in cancer chemotherapy

NASA Astrophysics Data System (ADS)

Asthana, Shalini; Gupta, Pramod K.; Konwar, Rituraj; Chourasia, Manish K.

2013-09-01

Nanocarriers can be surface engineered to increase endocytosis for applications in delivery of chemotherapeutics. This study investigated the chitosan (CS)-mediated effects on the anticancer efficacy and uptake of docetaxel-loaded nanometric particles (<250 nm) by MCF-7 tumor cells. Herein, negatively charged poly lactic- co-glycolic acid (PLGA) nanoparticles (-18.4 ± 2.57 mV, 162 ± 6.34 nm), poorly endocytosed by the MCF-7 cells, were subjected to surface modification with CS. It demonstrated significant increase (>5-fold) in intracellular uptake as well as antitumor efficacy of modified nanoparticles (NPs) that explicate the possibility of saccharide marker-mediated tumor targeting along with synergism via proapoptotic effect of CS. Additionally, high positivity of optimized tailored nanocarrier (+23.3 ± 2.02 mV, 242.8 ± 9.42 nm) may have accounted for the increased adsorption-mediated endocytosis, preferably toward tumor cells with negative potential. Developed drug carrier system showed high stability in human blood which is in compliance with mucoadhesive property of CS. Transmission electron microscopy technique was applied to observe shape and morphological features of NPs. Furthermore, in vivo tissue toxicity study revealed safe use of drug at 20 mg/kg dose in nanoparticulate form. Moreover, the enhanced in vitro uptake of these NPs and their cytotoxicity against the tumor cells along with synergistic effect of CS clearly suggest that CS-modified carrier system is a promising candidate for preclinical studies to achieve wider anti-tumor therapeutic window and lower side effects.

Design and Evaluation of Multi-functional Nanocarriers for Selective Delivery of Coenzyme Q10 to Mitochondria

PubMed Central

Sharma, Anjali; Soliman, Ghareb M.; Al-Hajaj, Noura; Sharma, Rishi; Maysinger, Dusica; Kakkar, Ashok

2016-01-01

Impairments of mitochondrial functions have been associated with failure of cellular functions in different tissues leading to various pathologies. We report here a mitochondria–targeted nanodelivery system for coenzyme Q10 (CoQ10) which can reach mitochondria, and deliver CoQ10 in adequate quantities. Multifunctional nanocarriers based on ABC miktoarm polymers (A= PEG, B = polycaprolactone (PCL) and C = triphenylphosphonium bromide (TPPBr)) were synthesized using a combination of click chemistry with ring opening polymerization, self-assembled into nano-sized micelles, and were employed for CoQ10-loading. Drug loading capacity (60 weight%), micelle size (25–60 nm) and stability were determined using a variety of techniques. The micelles had a small critical association concentration, and were colloidally stable in solution for more than 3 months. The extraordinarily high CoQ10 loading capacity in the micelles is attributed to good compatibility between CoQ10 and PCL, as indicated by low Flory-Huggins interaction parameter. Confocal microscopy studies of fluorescently labeled polymer analog together with the mitochondria-specific vital dye label, indicated that the carrier did indeed reach mitochondria. The high CoQ10 loading efficiency allowed testing of micelles within a broad concentration range, and provided evidence for CoQ10 effectiveness in two different experimental paradigms: oxidative stress and inflammation. Combined results from chemical, analytical and biological experiments suggest that the new miktoarm-based carrier provides a suitable means of CoQ10 delivery to mitochondria without loss of drug effectiveness. The versatility of the click chemistry used to prepare this new mitochondria-targeting nanocarrier offers a widely applicable, simple and easily reproducible procedure to deliver drugs to mitochondria or other intracellular organelles. PMID:22148549

Determining drug release rates of hydrophobic compounds from nanocarriers.

PubMed

D'Addio, Suzanne M; Bukari, Abdallah A; Dawoud, Mohammed; Bunjes, Heike; Rinaldi, Carlos; Prud'homme, Robert K

2016-07-28

Obtaining meaningful drug release profiles for drug formulations is essential prior to in vivo testing and for ensuring consistent quality. The release kinetics of hydrophobic drugs from nanocarriers (NCs) are not well understood because the standard protocols for maintaining sink conditions and sampling are not valid owing to mass transfer and solubility limitations. In this work, a new in vitroassay protocol based on 'lipid sinks' and magnetic separation produces release conditions that mimic the concentrations of lipid membranes and lipoproteins in vivo, facilitates separation, and thus allows determination of intrinsic release rates of drugs from NCs. The assay protocol is validated by (i) determining the magnetic separation efficiency, (ii) demonstrating that sink condition requirements are met, and (iii) accounting for drug by completing a mass balance. NCs of itraconazole and cyclosporine A (CsA) were prepared and the drug release profiles were determined. This release protocol has been used to compare the drug release from a polymer stabilized NC of CsA to a solid drug NP of CsA alone. These data have led to the finding that stabilizing block copolymer layers have a retarding effect on drug release from NCs, reducing the rate of CsA release fourfold compared with the nanoparticle without a polymer coating.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'. © 2016 The Author(s).

Determining drug release rates of hydrophobic compounds from nanocarriers

PubMed Central

D’Addio, Suzanne M.; Bukari, Abdallah A.; Dawoud, Mohammed; Bunjes, Heike; Rinaldi, Carlos; Prud’homme, Robert K.

2016-01-01

Obtaining meaningful drug release profiles for drug formulations is essential prior to in vivo testing and for ensuring consistent quality. The release kinetics of hydrophobic drugs from nanocarriers (NCs) are not well understood because the standard protocols for maintaining sink conditions and sampling are not valid owing to mass transfer and solubility limitations. In this work, a new in vitroassay protocol based on ‘lipid sinks’ and magnetic separation produces release conditions that mimic the concentrations of lipid membranes and lipoproteins in vivo, facilitates separation, and thus allows determination of intrinsic release rates of drugs from NCs. The assay protocol is validated by (i) determining the magnetic separation efficiency, (ii) demonstrating that sink condition requirements are met, and (iii) accounting for drug by completing a mass balance. NCs of itraconazole and cyclosporine A (CsA) were prepared and the drug release profiles were determined. This release protocol has been used to compare the drug release from a polymer stabilized NC of CsA to a solid drug NP of CsA alone. These data have led to the finding that stabilizing block copolymer layers have a retarding effect on drug release from NCs, reducing the rate of CsA release fourfold compared with the nanoparticle without a polymer coating. This article is part of the themed issue ‘Soft interfacial materials: from fundamentals to formulation’. PMID:27298440

Synthesis, antimicrobial activity and toxicity of analogs of the scorpion venom BmKn peptides.

PubMed

Bea, Roberto de la Salud; Petraglia, Adam Fine; Johnson, Laura Elena Luque de

2015-07-01

Two analogs of the natural peptide BmKn1 and four of BmKn2 found in the venom of the scorpion Buthus martensii Karsh have been synthesized and tested to compare their antimicrobial and hemolytic activity with the natural ones. Modifications of the natural sequence were done on the hydrophobic side of the alpha helix by increasing the size and hydrophobicity of the residues with alanine (BmKn2A1), valine (BmKn2V1) and leucine (BmKn2L1) respectively, and on the hydrophilic side by increasing the charge from +2 to +3 with two lysines (BmKn2K7). In order to study observed peptide aggregation, two peptides with one (BmKn1-6Lys) and two (BmKn1L2K2) positive charges respectively in the hydrophobic side have been also designed. Results show that the valine substituted analog BmKn2V1 and lysine substituted analog BmKn2K7 have in general, the highest antibiotic and hemolytic activity of the group. Introduction of one positive charge on the hydrophobic side shows a significant increase in antibacterial activity compared with the original sequence except for Bacillus and Enterobacter where, unexpectedly, the activity flats-off. In contrast, the analog with two positive charges has minimal antibacterial or hemolytic activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Kell hemolytic disease of the fetus. Combination treatment with plasmapheresis and intrauterine blood transfusion.