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Hindawi Publishing Corporation International Journal of Carbohydrate Chemistry Volume 2011, Article ID 865704, 14 pages doi:10.
Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Porto, Rua An´bal Cunha 164, 4050-047 Porto, Portugal ı Institut f¨ r Biologie und Biotechnologie der Pﬂanzen, Westf¨ lische Wilhelms-Universt¨t M¨ nster, Hindenburgplatz 55, u a a u 48143 M¨ nster, Germany u 3 The Group of Biomaterials and Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, 956 Jun´n Street, 6th Floor, 1113 Buenos Aires, Argentina ı 4 National Science Research Council (CONICET), C1033AAJ Buenos Aires, Argentina 5 CICS, Department of Pharmaceutical Sciences, Instituto Superior de Ciˆncias da Sa´ de-Norte, Rua Central de Gandra 1317, e u 4585-116 Gandra, Portugal Correspondence should be addressed to Bruno Sarmento, bruno.sarmento@ﬀ.up.pt Received 28 April 2011; Accepted 21 July 2011 Academic Editor: Jianjun Li Copyright © 2011 Fernanda Andrade et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Recently, much attention has been given to pulmonary drug delivery by means of nanosized systems to treat both local and systemic diseases. Among the diﬀerent materials used for the production of nanocarriers, chitosan enjoys high popularity due to its inherent characteristics such as biocompatibility, biodegradability, and mucoadhesion, among others. Through the modiﬁcation of chitosan chemical structure, either by the addition of new chemical groups or by the functionalization with ligands, it is possible to obtain derivatives with advantageous and speciﬁc characteristics for pulmonary administration. In this paper, we discuss the advantages of using chitosan for nanotechnology-based pulmonary delivery of drugs and summarize the most recent and promising modiﬁcations performed to the chitosan molecule in order to improve its characteristics.
Alongside the successful market launch of diﬀerent products over the last decades, a continuous eﬀort to formulate delivery systems for the pulmonary administration of a wide variety of drugs has been extensively described in the literature [1, 2]. The particular anatomical, physiological, and pathophysiological features of the respiratory tract pose enormous challenges that need to be overcome in order to obtain eﬀective lung deposition, uniform distribution, in loco retention (main challenge is to circumvent mucocilliary clearance), and stability (particularly to enzymatic degradation) of therapeutic agents [1, 3]. Nevertheless, particular attention has been dedicated not only to drugs themselves but also to excipients required to improve the bioavailability of drugs administered pulmonarily.
In this context, excipients that could transiently enhance the absorption of drugs are on the spot. Chitosan, a polysaccharide with structural characteristics similar to glucosamines and obtained by the alkaline deacetylation of chitin, derived from the exoskeleton of crustaceans, is one of such appealing excipients. The safety and tolerability of chitosan are synergistic characteristics towards its application in drug delivery by different administration routes. Despite the natural properties, some drawbacks are associated with the poor solubility at physiologic pH and the passive targeting eﬀect. Thus, chemical modiﬁcations of chitosan by conjugating various functional groups allow the control of the hydrophilicity and the solubility at neutral and basic pH and open new opportunities to expand the application of this biopolymer.
these eﬀects were milder. which can also be regarded as potentially useful for the development of pulmonary drug delivery systems. this eﬀect may be attributable not to the inherent toxicity of chitosan but most probably to the physical obstruction of the bronchioles due to higher viscosity of the chitosan formulation.3 mg/mL of nanoparticles were tested) to adenocarcinoma epithelial lung cell lines (Calu-3 and A549). Chitosan is a cationic mucoadhesive polymer. Moreover.. Also. antimicrobial  and antioxidant [6. The ability to establish ionic. either in the presence or absence of chitosan. Studies have also been conducted for derivatives of chitosan or chitosan-based formulations intended for pulmonary administration. stearic acid-g-chitosan oligosaccharide micelles presented an IC50 value of approximately 369 μg/mL . Grenha et al. in particular macromolecules.e. General advantages include the wellestablished biocompatibility and biodegradability of chitosan . Absorption enhancement was higher for higher MW isothiocyanate dextran. thiolation (i. The mucoadhesive properties of the native polymer can be further increased by chemical modiﬁcation. immune stimulation may . attachment of side chains containing thiol groups) has been proved an interesting strategy for this last purpose . glycol chitosan).and nanocarriers) that can be optimized in order to present optimal aerodynamic particle diameters for lung deposition and retention [8–11]. In the case of TMC.  reported on the enhanced mucoadhesion of nanoparticles composed of thioglycolic acid-glycol chitosan.  performed in vivo studies in rats by administering intratracheally chitosan and two brands of N-trimethylated chitosan (TMC). Toxicological data on chitosan has been extensively reviewed and is regarded to be favorable when considering its use as a pharmaceutical excipient . 7] activities have been reported for diﬀerent types of chitosan and derivatives.. the structural component of mucus ﬂuids. However. the increment in pulmonary mucoadhesion observed by these researchers was correlated with the greater bioavailability of calcitonin when this peptide was associated with nanoparticles. International Journal of Carbohydrate Chemistry OH O HO O O HO O CH3 NH OH O O 2. presenting diﬀerent degrees of substitution (20% and 60%). after intratracheal administration to rats.  showed that chitosan nanoparticles obtained by ionotropic gelation with tripolyphosphate and entrapped in mannitol microparticles presented reduced toxicity (concentrations of up to 1.e. In another study conducted in A549 cells. due to the transiently disruption of tight junctions (Figure 2) . However. The processability of chitosan and several derivatives allow obtaining diﬀerent types of systems (powders or wellstructured micro. the production of several proinﬂammatory cytokines has been observed for hydrophobically modiﬁed glycol-chitosan nanoparticles in vivo after intratracheal instillation in mice . we revise some of the most recent and promising modiﬁcations performed to chitosan with special focus on its employment in the pulmonary delivery of drugs. which could be associated with lower viscosity when compared to chitosan. Histopathological analysis of lung tissue showed that chitosan elicited neutrophil inﬁltration and structural damage in the lung parenchyma. thus causing local asphyxiation. In one recent study. the presence of reactive amine groups grants chitosan the chemical versatility for modiﬁcation and functionalization (Figure 1) . providing evidence for the mechanism of intercellular tight junction disruption. Comparable inﬂammatory eﬀects were also observed in rats after the intratracheal administration of chitosan microparticles . chitosan and derivatives may also induce immune responses by lung cells/tissue. Results showed signiﬁcantly higher permeation for all the investigated model drugs in the presence NH2 Figure 1: Chemical structure of chitosan.  performed in vivo experiments in guinea pigs by comparing the pulmonary absorption of different model drugs in solution (carboxyﬂuorescein and ﬂuorescein isothiocyanate dextran with molecular weight (MW) varying from 4 to 70 kDa). Moreover. mucoadhesive properties of chitosan and derivatives may also be detrimental. as assessed by blood drug levels. Calu-3 cells exposed to chitosan microparticles were able to elicit the release of inﬂammatory cytokines (IL-2 and IL-8) . since adhesion of delivery systems at the upper respiratory tract and airways can also occur. In an in vitro study. however. comprising N-acetyl-Dglucosamine (right) and D-glucosamine (left) units. Florea et al. Advantages of Chitosan for Pulmonary Delivery of Drugs Chitosan possesses diﬀerent beneﬁcial properties that make it an attractive option for designing adequate dosage forms and advanced drug delivery systems to be administered to or through the lung. For instance. of chitosan. hydrogen.2 In this paper. as compared to nanoparticles based on the nonthiolated polymer (i. in vitro cytotoxicity experiments were conducted for chitosan presenting diﬀerent degrees of deacetylation and MW using human embryonic lung cells (L132 cells) . More importantly. In order to conﬁrm this eﬀect in pulmonary drug delivery. evidences its potential for increasing lung retention of drug carriers comprising chitosan. and hydrophobic bonding with negatively charged chains of mucin . thus limiting the amount of carrier that eﬀectively reaches the deep lung. In particular. Results revealed that chitosan presented 50% inhibitory concentration (IC50 ) values higher than 1 mg/mL. Yamamoto et al. Chitosan is able to enhance absorption of drugs by the paracellular route. which is mainly absorbed by the paracellular route. Makhlof et al. Even if generally regarded as detrimental. In the particular case of pulmonary drug delivery. Formulating scientists should keep this phenomenon in mind when developing chitosan-based systems.
An increase in the degree of quaternization leads to increase of the permeation-enhancing eﬀect of TMC .International Journal of Carbohydrate Chemistry 3 3 1 2 (a) (b) Figure 2: Eﬀect of chitosan on the absorption of drugs by the paracellular route. TMC has CH3 CH3 Figure 3: Chemical structure of trimethyl chitosan (showing the modiﬁcation at the D-glucosamine unit).5-. Chitosan and Chitosan-Grafting Copolymers for Nanoparticle-Based Pulmonary Drug Delivery Systems The ﬁrst nanoparticles with drug delivery purposes began in the late 1960s . 2. This capability as enhancer is due to opening the tight junctions between adjacent epithelial cells through interactions between the protonated (positively charged) amino groups on the C-2 position and the negatively charged sites on the cell membrane and/or in the tight junctions . TMC-based nanoparticles have consistently shown their feasibility for mucosal immunization. respectively.. TMC is obtained by reductive methylation of chitosan using methyl iodide in the presence of a strong base (e. nanoparticles can be used therapeutically as carriers. 3. depending on the application ﬁeld . positive charges. at all degrees of quaternization . and their transport across the nasal epithelium of rat was studied . Florea et al. synergistic eﬀects of the TLR9 ligand CpG in TMC particles have been reported after nasal vaccination . A similar approach was assessed with the tetanus toxoid by nasal instillation in mice . the bioavailability was enhanced by 2. and 3: represents chitosan. NaOH) at 60◦ C [33.g. Studies have addressed oral vaccination against Helicobacter pylori using urease . or encapsulating the active substance (drug or biologically active material) or by adsorbing or attaching the active substance on the surface. 32]. observed that 20% and 60% N-TMC (TMC20 and TMC60) enhanced the permeation of octreotide in vitro by 21-.1. This soluble chitosan derivative has mucoadhesive properties and displays excellent absorptionenhancing properties. be a particularly interesting feature for vaccine development . independently of the pH. TMC nanoparticles were loaded with FTIC ovalbumin. 1: represents the drug.9-fold. For pharmaceutical and medical applications. Trimethyl Chitosan (TMC). Trimethylated chitosan (TMC) is a partially quaternized chitosan derivative that is freely soluble in aqueous solutions over a wide range of pH as compared to other chitosan salt derivatives (Figure 3). 36]. and 3. in this section. Since this natural polymer oﬀers remarkable advantages over other natural and synthetic polymeric carriers. O OH O HO H3 C N+ 3. although sometimes the term identiﬁes particles in the 1 to 200 nm range. 2: represents the tight junction. Intranasal administration of the inﬂuenza antigen elicited local and systemic immune responses in mice . either by dissolving. we will focus on chitosangrafting-based polymeric nanoparticles as drug carriers. entrapping. (a) Normal epithelium. In turn. even at neutral pH [35. Cell viability and histology studies showed that the TMCs are safer than chitosan and that Calu-3 cell monolayers are a valuable model for predicting the paracellular transport kinetics in . A recent study has also shown that the delivery of the model antigen ovalbumin (OVA) to the cervical lymph nodes in a nanoconjugated form with TMC (∼30 nm diameter) was twice more eﬀective than the nasal administration of ovalbumin-containing TMC nanoparticles with size of one order of magnitude greater (∼300 nm diameter) . 34].4-. 16-. (b) Transient disruption of tight junctions by chitosan with enhancement of drug absorption. Diﬀerent nanoparticles have been developed for pulmonary administration of various drugs to treat diseases such as tuberculosis (TB) [28–30] and other pulmonary infections  and diseases [31. and 30-fold. Nanoparticles are solid colloidal particles made of macromolecular materials ranging in size from 1 to 1000 nm. Also.
apart from the reduction of the cytotoxicity. At room temperature the O-substitution is favored. O-. it is necessary to carry out studies to test the feasibility of these NPs as inhaled drug delivery systems.6%) leading to insulin loading values as high as 38.3. Like other derivatives. Shi et al. Control cells without any exposure to NPs and cells incubated with O-CMC NPs showed no ﬂuorescence. In addition. Diﬀerent substitutions patterns can be obtained according to the reaction temperature used (Figure 4). NSC was initially developed as a wound dressing material combined with collagen. they sustain that cationic polysaccharides are promising enhancers for peptide drug absorption with prospect for sustainedrelease formulations . Conjugation of the antigen to TMC and TMC/OVA is therefore a viable strategy to increase the immunogenicity of subunit vaccines . induced by loaded nanoparticles. that is. synthesized a new NSC derivative by means of microwave irradiation. Other studies have shown that. MCF-7. reported on the conjugation of an antigen. N-. Chitosan-g-PEG nanoparticles have been prepared by ionotropic gelation with TPP . Hou et al. 3. PEGylation of TMC led to improved colloidal stability of polyplexes and signiﬁcantly increased . the antitumor eﬀect of NSCNP is achieved by necrosis and apoptosis induction in K562 cells. so that the particles can be “invisible” to phagocytic cells. and 48 h.O-. 10. the cell apoptosis rate was increased from 30% after 24 h to 62% at the end of 72 h. Conversely. Some authors have used this chitosan derivative to prepare anticancer-drug-loaded NPs. 3.4. diﬀerent derivatives can be produced. Results of in vivo studies after intranasal administration to healthy rabbits showed that the plasma glucose levels fell sharply and remained at a low concentration for. 2-3 h and returned to baseline after 5 h. 14. PEGylated Chitosan. According to a cytomorphology study and the analysis of DNA fragments. Luo et al.6%. This system displayed a high association eﬃciency (>78.93. N. and 9. NSC is a chitosan derivative obtained by the incorporation of succinyl moieties into the N-terminal group of the glucosamine units (Figure 5) . N-Succinyl-Chitosan (NSC). For example. prepared similar nanoparticles loaded with 5-ﬂuorouracil (5-FU) . cells incubated with curcuminO-CMC NPs displayed green ﬂuorescence. Therefore. It is also recognized as an excellent cosmetic ingredient (Moistﬁne liquid. These nanoparticles were not tested for any speciﬁc route of administration.78. The uptake of TMCOVA conjugates by dendritic cells was similar to the uptake of TMC/OVA nanoparticles and over 5-fold greater when compared to a solution of OVA and TMC. 3. the O-CMC NPs without drug showed no cytotoxicity. In vitro studies showed that TPs were controlled released from nanoparticles in PBS at pH 7. administration in Sarcoma 180-bearing mice. and PC-3 cell lines.4. CMC is prepared by carboxymethylation of the hydroxyl and amine chitosan groups . In another work. An interesting ﬁnding of this study was that TMCMCC composite nanoparticles obtained by electrostatic complexation of the two polymers with a positive surface charge exhibited higher immune responses when compared to chitosan. Grafting of hydrophilic polymers such as PEG onto chitosan is a well-known strategy to improve the solubility and biocompatibility of chitosan as well as to achieve lower recognition by the host immune system and increased blood circulation time (Figure 6) . CMC-based nanoparticles of varying average size (40– 400 nm diameter) were developed for intranasal immunization . INCI name Chitosan Succinamide). Yan et al. OVA. conﬁrming the internalization of the particles . NSC displays good water solubility in a broad pH range. Cellular uptake was analyzed by ﬂuorescence microscopy. to TMC and the preparation of nanoparticles for subunit vaccination. Li et al. Taking into account these results.78 υg/mL at 12. TMC. For example. respectively. injection (close to the tumor) in mice bearing S180 sarcoma tumor . prepared nanoparticles with oleoyl-carboxymethyl chitosan encapsulating rifampicin as drug delivery systems International Journal of Carbohydrate Chemistry . CMC is prepared by adding a carboxymethyl group in the structure of chitosan. being found small quantities in kidney and spleen . Due to the advantages that PEG confers to chitosan. evaluated antitumor eﬀects of NSC nanoparticles (NSCNPs) without drugs in K562 cells . chitosan-g-PEG copolymer has been prepared and utilized to develop various types of nanocarriers for transmucosal drug delivery. They evaluated biodistribution and tumor targeting after i. 36. But their pulmonary administration could be a possibility to treat tuberculosis.26.v. used diﬀerent kinds of CMC with various molecular weights and degrees of substitution to prepare nanoparticles through ionotropic geliﬁcation with calcium ions. These results showed the feasibility of CMC nanoparticles to entrap doxorubicin and the potential to deliver it following a controlled proﬁle . Slutter et al. and MCC nanoparticles. In L929.c. while at higher temperature the Nsubstitution is the preferred pathway. This modiﬁcation increases its solubility in neutral and basic solutions without aﬀecting other important characteristics . or N. CMC nanoparticles were prepared as carriers for some anticancer drugs. Taking into account reaction conditions and reagents.N-dicarboxymethyl chitosan .4 the airway epithelia. and it is considered biocompatible both in vitro and in vivo. Carboxymethyl Chitosan (CMC). These PEG chains create a barrier layer to prevent the adhesion of opsonins present in the blood. tea polyphenols (TPs) were loaded into carboxymethyl chitosan and chitosan hydrochloride . whereas curcumin and curcumin-O-CMC NPs resulted in considerable cell death. prepared curcumin-loaded O-CMC nanoparticles (curcumin-O-CMC Nps) as a novel carrier in cancer drug delivery applications. at most. 24.2. The results revealed that NSCNP could inhibit the proliferation of K562 with an IC50 of 37. Anhitha et al. The 5-FU-loaded NPs were biodistributed mainly in the tumor and liver. They entrapped successfully hydroxycamptothecin (HCPT) into the NSC nanoparticles and observed tumor targeting and signiﬁcant suppression of tumor growth after s.
Thiolated Chitosan. it was documented that thiolated chitosan has strong mucoadhesive properties ascribed to the formation of disulﬁde bonds with cysteine-rich domains of mucus glycoproteins. . up to 10-fold. lactobionic acid (LA) in chitosan . 3. Insulin-loaded nanoparticles prepared with chitosan-Nacetyl-L-cysteine were found to improve the systemic absorption of insulin after nasal administration . L929. Thiol modiﬁcations to chitosan and nanoparticles derived from it have been aimed to localize a drug delivery system at a given target site (Figure 7). Mao et al. (3) O-CMC. Recently. with higher depositions in kidney and liver . For this. These improvements resulted in a signiﬁcant. and MeWo cells. They conjugated PEG on the nanoparticles and observed that the clearance of the PEGylated nanoparticles in male AKR/J mice (6–8 weeks) following intravenous administration was slower than that of unmodiﬁed nanoparticles at 15 min. (2) N. Although the exact mechanism for the enhanced eﬀectiveness of this Figure 6: PEG-g-chitosan as obtained by the two most commonly used synthetic routes: (1) reaction with an active ester derivative and (2) reductive amination. They observed that the system with ligand chitosan-(O-MPEG)-(N-LA) showed better transfection eﬃciency (45.International Journal of Carbohydrate Chemistry OH O O HO HO O O (1) O OH O O O HO NH2 O HO HO O (3) (4) (2) O OH O O NH O NH O HO HO N OH OH O 5 Figure 4: Chemical structure of diﬀerent types of carboxymethyl chitosan (CMC): (1) N-CMC. prepared chitosan-DNA nanoparticles using a complex coacervation process .3%) than ligandfree chitosan-(O-MPEG) (19. OH O HO O NH OH O O Figure 5: Chemical structure of N-succinyl-chitosan (showing the modiﬁcation at the D-glucosamine unit).8%). Other authors developed a functional nanoparticulate carrier for DNA transfection in asialoglycoprotein receptor overexpressed in HepG2 cells. leading to an improvement in mucoadhesion of up to 140-fold when compared to unmodiﬁed chitosan .OCMC (showing the modiﬁcation at the D-glucosamine unit). and (3) N. X: linker. increase of transfection eﬃciency in NIH/3T3. OH O HO O O MeO O n OH O HO O MeO O n (2) O NH X O NH O (1) cellular uptake compared to unmodiﬁed TMC .N-CMC. they grafted a methoxy PEG (MPEG) and a receptor ligand.5.
with emphasis on poorly soluble anticancer drugs [69–73]. The concentration and the temperature above which the monomers turn in micelles are called critical micelle concentration (CMC) and critical micellization temperature (CMT). Chitosan-Based Polymeric Micelles for Pulmonary Drug Delivery Micelles are spherical nanosized colloidal dispersions with a hydrophobic core and hydrophilic shell. Recently. 67]. It is also possible to promote the targeting of drugs to speciﬁc organs and tissues using stimuli-responsive micelles [77–79] or modulating the micellar surface with active-targeting ligands [77. generally di. In this section. for pulmonary administration of various drugs to treat diﬀerent diseases such as cancer . much attention has been given to polymeric micelles formed by lipid polymer or block copolymers. Water-soluble drugs are adsorbed on the micelle surface. Furthermore. Chitosan-Based Micelles. The same research group developed SACSO micelles for the delivery of drugs like paclitaxel . 77]. and pulmonary infections [84–86]. Two forces are involved in the micelle formation. and drugs with intermediate polarity are distributed along the amphiphilic molecules . polymeric micelles can be a useful strategy to solve the problem of drug resistance . By sharing some structural and functional features with natural transport systems. making these micelles a promising gene delivery system in the treatment of pulmonary diseases. polymeric micelles allow the encapsulation of drugs with diﬀerent polarities. The self-assembly of amphiphilic molecules in water is driven by a gain in entropy of the solvent molecules and a decrease of free energy in the system as the hydrophobic components withdraw from the aqueous media . as drug delivery systems. an attractive force that leads to the association of molecules and a repulsive force that prevents unlimited growth of the micelles . Micelles can be used as drug delivery systems. Recently. micelles are poorly recognized by the reticuloendothelial system (RES) and present long circulation times in bloodstream with enhanced permeability and retention eﬀects (EPR eﬀect) at solid tumor sites or another areas with leaky vasculature such infarcts. They have been also studied as carriers of genetic material to treat cystic ﬁbrosis .1. chitosan can be complexed with negatively charged DNA and be used as nonviral vector for gene therapy. system remains unclear. making them more physically stable. composed by am-phiphilic molecules which self-assembly under certain concentration and temperature conditions (Figure 8). Figure 7: Thiolated chitosan: (1) general structure of thiolated chitosan as modiﬁed by an –SH group and (2) chitosan-N-acetylcysteine (showing the modiﬁcation at the D-glucosamine unit). and inﬂammations. for example. 91]. Due to its size. 4. and proteins . inﬂammation conditions . micelles have the ability to penetrate tissues. showing also a high encapsulation eﬃciency and possibility of sterilization by ﬁltration [63. infections. The SA-CSO/DNA micelles eﬃciently protected the condensed DNA from enzymatic degradation by DNAse I and presented lower cytotoxicity and comparable transfection eﬃciency in A549 cells compared to Lipofectamine 2000 . Due to its cationic nature. hence. it was speculated that the mucoadhesive and permeation-enhancing properties based on disulﬁde bond “anchorage” increase the accessibility of insulin molecules to the epithelial membrane and. 4. virus and lipoproteins. SA-CSO micelles were developed by another . 80]. Hu and coworkers synthesized stearic acid. The encapsulation of doxorubicin in SA-CSO micelles resulted in higher uptake and accumulation by A549 cells and a decrease in the IC50 . polymeric micelles present a lower CMC value. facilitates the absorption of the protein across the nasal epithelium. Compared to micelles prepared from conventional detergents. for passive targeting [76. especially for poorly water-soluble drugs that are incorporated into the micelle core.and triblock copolymers. doxorubicin [90. Like liposomes. both in vitro and in vivo. However. they are more stable than liposomes. X: linker. generally lower than 200 nm. due to its general small size. 66. They have also been studied as carriers of genetic material  and diagnostic agents . even under dilutions to ﬁnal concentration below the CMC . and hydrophilic surface.(SA-) grafted chitosan oligosaccharide (CSO) in order to produce polymeric micelles to delivery pDNA (pEGFP-C1) . Many studies have been published in the last years regarding the use of polymeric micelles as solubilization agents and bioavailability enhancers of diﬀerent drugs. in the last years. respectively . Diﬀerent polymeric micelles have been developed.6 OH O O HO X SH NH O (1) (2) NH O HO O SH OH O International Journal of Carbohydrate Chemistry CMC NH CMT Figure 8: Formation of micelles by self-assembly of polymer monomers above critical micelle concentration (CMC) and critical micellization temperature (CMT). we will focus on chitosanbased polymeric micelles as drug carriers.
the micelle size and drug-loading content increased. their application has been centered particularly in noninvasive routes of administration including transmucosal administration of proteins [121–125] and genetic material [126–130]. The present systems were not tested for any speciﬁc route of administration. its mucoadhesiveness [113. They also synthesized N-alkyl-N-trimethyl chitosan derivatives to deliver 10-hydroxycamptothecin. but significantly reduced toxicity and improved bioavailability . resp. Another research group studied the feasibility of N-succinyl-N-octyl chitosan as delivery system of doxorubicin .(PLA-) chitosan copolymers with diﬀerent molar ratios were developed and characterized. with reference to speciﬁc systems. The micelles possessed positive charges with mean diameters between 100 and 250 nm and were eﬃciently nebulized using an Air-jet nebulizer presenting up to 52% of ﬁne particle fraction.and nanoscopic scales. mannose) or speciﬁc ligands such as folate. Nanocarrier systems of this kind with improved biological and biopharmaceutical performance have been the subject of active research in the past decade or so. and capacity to promote the absorption of poorly absorbable macromolecules across epithelial barriers by transient widening of cell tight junctions thus modifying the parallel transport [117–120] have been exploited in the development of nanocarrier systems for transmucosal delivery. as discussed. 131]. Conjugation of Sugar Ligands. 105]. Galactose groups were chemically bound to . Liu and coworkers developed an triblock copolymer consisting of poly(ε-caprolactone)-b-chitooligosaccharide-b-poly(ethylene glycol) (PCLb-COS-b-PEG) for delivery of drugs. Polylactide. thiolated derivatives. As a consequence. Rifampicin was used as lipophilic drug model to be encapsulated. galactose. using chitosanpoly(ε-caprolactone)-poly(ethylene glycol) to encapsulate paclitaxel and rutin with glutaraldehyde after crosslinking . Particularly. and presented similar antitumor eﬃcacy as Taxol. a phenomenon intimately related to its aggregation state . it is also possible to produce chitosan derivatives with amphiphilic characteristics that may self-assemble in aqueous environment and form polymeric micelles [99–101]. 7 Their pulmonary administration could be a possibility to treat locally lung cancer.. Genipin after crosslinking did not aﬀect the macroscopic characteristics of the micelles but delayed the in vitro release of doxorubicin from the micellar reservoir . The capacity of chitosan to undergo multiple chemical modiﬁcations has been exploited to increase the active targeting of chitosan-based nanocarriers particularly for protein and genetic material delivery towards speciﬁc cells [126. After encapsulation into micelles. 114]. Between the different derivatives. using doxorubicin as model drug . making them a suitable choice for pulmonary delivery of AmB . 5.1. biocompatibility [115. AmB presents the same antifungal activity of Fungizone but lower toxicity . chitosan is an ideal natural polymer for the design and development of drug delivery systems structured at micro. avoids the systemic side eﬀects and improves the bioavailability of the drug . the N-lauryl-carboxymethyl-chitosan micelles developed by Miwa et al. . The obtained polymer presents the capacity to form micelles with encapsulation eﬃciency of doxorubicin close to 50%. however. present in some patients receiving immune suppressive treatments. Examples are the N-mPEG-N-octylO-sulfate chitosan micelles produced by Qu and co-workers . N-octyl-O-sulfate chitosan presented the best results in terms of solubilization of paclitaxel . 112]. In the ﬁeld of block copolymers. Chitosan-based polymeric micelles have also been developed as drug delivery systems for other routes of administration than pulmonary. As PLA molar ratio increased. with emphasis on intravenous administration of paclitaxel. Strategies to improve the targeting potential of chitosan have addressed its functionalization with sugar moieties. grafted PEG) to conjugation with biologically active ligands such as carbohydrates (e. 110] or the methoxy poly(ethylene glycol)grafted chitosan micelles for delivery of methotrexate to treat colon carcinoma [111. for the pulmonary administration of amphotericin B (AmB) .) . and the rifampicin release rate decreased . stability. they present antitumor eﬃcacy against lung cancer cell lines such as Lewis lung cancer cells  and A549 cells [103.g. studies are required to access its feasibility as inhaled drug delivery systems. Zhang and co-workers synthesized diﬀerent chitosan derivatives composed by long-chain alkyl groups as hydrophobic moieties and sulfated groups as hydrophilic moieties to delivery of paclitaxel . or KNOB viral protein. for intercellular antitumor drug delivery to drug resistance tumor cells [109. Similar results were obtained by Chen et al. Other chitosan-based micelles have been developed such as the doxorubicin-loaded linoleic acidgrafted chitosan oligosaccharide micelles produced by Du et al. release behavior. in the following sections. The best results in terms of encapsulation eﬃciency. transferrin. and pharmacokinetic properties were obtained with Noctyl-N-trimethyl chitosan (degree of octyl and trimethyl substitution is 8% and 54%. 5.International Journal of Carbohydrate Chemistry research group. Chitosan-Ligand Conjugates for Nanoparticle-Based Active Target Drug Delivery Systems As discussed in previous sections. Wu and co-workers also synthesized chitosan-based copolymers for drug delivery . 116].. Paclitaxel-loaded micelles prepared with N-octyl-O-sulfate chitosan had high drug-loading capacity and encapsulation eﬃciency.g. mostly with D-galactose and D-mannose. Although these systems have been tested for intravenous administration. The modiﬁcations have comprised from derivatization with small functional groups or substructures (e. were shown to be safe for intravenous injection. The local administration of AmB to treat invasive pulmonary fungal infections. and the N-octyl-N-(2-carboxylcyclohexamethenyl) chitosan micelles produced by Liu and co-workers . Besides the creation of lipid-chitosan and polymer-chitosan conjugates. A recognized feature of chitosan-based nanostructured systems is their capacity to protect sensitive therapeutic macromolecules against degradation and their ability to overcome mucosal barriers.
Tf decoration of chitosan-based DNA-loaded nanoparticles has been found to enhance the transport across polarized monolayer Caco-2 cells known to have abundant Tf receptors on their surface  and extensively used as a model of normal intestinal epithelium transport . such as transferrin and viral KNOB. the high aﬃnity of folate to bind its receptor (1 nM)  and folate small size allows its use for speciﬁc cell targeting. These systems have been developed with a view to achieve targeting eﬀect in the delivery of cytostatic drugs to tumor cells.to 5-fold. this system allowed for an increase in IL-1Ra expression combined with a diminution of cytotoxicity in vitro and reinforced protection against inﬂammation and abnormal bone metabolism in vivo. HepG-2 . This system was found to enhance the transfection of HepG2 cells having ASGRr. The transferrin receptor (TfR) is found in many mammalian cells. which then complexed with pcDNA. It was demonstrated that Tf conjugation could enhance the transport of nanoparticles through Caco-2 alone and Caco-2-PPL cocultures by 3. To this end. Conjugation of Folate. This same system was tested in vivo by a diﬀerent group. or antiarthritis therapies and also for diagnostic and imaging purposes. Using these nanoparticles in the delivery of a plasmid encoding IL-12 resulted in enhanced IL-12 gene transfer eﬃciency. It was found that this system has the potential to be a vector for targeting to Kupﬀer cells in vivo. International Journal of Carbohydrate Chemistry The evidence from most of these studies is consistent to indicate that the folic acid modiﬁcation promotes the uptake of nanoparticles by FR-positive tumor cell lines most likely via receptor-mediated endocytosis but has little impact on other cells without FR . The results led to suggest that uptake in the lymphoid follicles of the duodenum could play a more signiﬁcant role compared to Peyer’s patches . Caco-2 . Other chitosan glycoconjugates have incorporated lactose to develop gene nanocarriers. GCP-DNA complexes were found to be stable due to hydrophobic shielding by PEG and increased the stability against DNAse degradation. Folic acid (FA) is appealing as a ligand for targeting cell membrane and allowing nanoparticle endocytosis via the folate receptor (FR) for higher transfection yields. Glycoconjugated chitosan was designed for ASGRr-directed delivery to liver parenchymal cells. which speciﬁcally recognizes the galactose ligands on modiﬁed chitosan .2. TEM evidence was consistent with the proposal that the nanocomplexes were internalized by HeLa cells and located inside endocytotic vesicles and endosome-like compartments . Hence. This modiﬁcation increased the carrier uptake and transfection eﬃciencies in various in vitro assays as well as in mouse lung tissue as recently reviewed elsewhere . the majority of in vitro studies have been conducted in various types of cell lines well known to overexpress the human folate receptors (FRa and FLRb). the ability of FA to bind its receptor to allow endocytosis is not altered by covalent conjugation of small molecules . as a strategy to achieve active targeting and thus high transfection eﬃciency [59. folate conjugation to the surface of chitosan and chitosan-derivatives-based nanoparticles has been one of the actively studied strategies to vectorize drugs over the past few years [140–149]. HeLa cells were eﬀectively transfected by this nanocarrier system. In turn. Importantly. suppressed tumour growth and angiogenesis in the carcinoma BALB/c mouse model . Compared to unmodiﬁed chitosan or naked DNA. 157]. 154] cells. The system was found eﬃcient to transfect liver cells expressing asialoglycoprotein receptor (ASGRr). the Tf-decorated nanoparticles did not show signiﬁcant enhancement of the transfection of HeLa cells . Transferrin (Tf) or antibodies against TfR were conjugated to oligonucleotides or polycations. chitosan has been functionalized with mannose. Moreover. Two diﬀerent synthetic approaches were tested to couple Tf to the surface of chitosan nanoparticles. KB [151. Galactosylated chitosan-graft-PEG (GCP) was developed for the same purpose. but neither HepG2 nor BNL CL2 cells. However. NPs made out of folategrafted chitosan were produced to transfect interleukin-1 receptor antagonist (IL-1Ra) in synovial mononuclear cells and CD14+ cells via the targeting of the folate receptor-b . achieving a conjugation in both cases about 33–43% (transferrin to chitosan moL%) . eﬀorts have been made to target mannose receptors on dendritic cells residing in tumors. Proteins. B16F1 . In turn. responsible for iron import to cells. A trisaccharide branch was attached onto chitosan chain in order to target lectins on the cell surface in lung tissues . An interesting contribution of this study was to address the behavior of a coculture of polarized Caco-2 cells inﬁltrated with lymphocytes that induces the diﬀerentiation of M-type phenotype. In this study HEK293 cells were transfected using luciferase reporter gene. hence. genetic material. have been conjugated at the surface of chitosan-based nanoparticles intended for DNA delivery. and SKOV3 [141. HT29 . thus indicating that galactosylated chitosan is an eﬀective hepatocyte-targeted gene carrier . such as HeLa . a model much closer to the real intestinal epithelium. One drawback of these systems is that they only proved to be ineﬀective in the presence of added serum medium. 5. A second related strategy has been to decorate the surface of DNA-loaded chitosan-based nanoparticles with KNOB protein so as to enhance the uptake and overcome one of the major rate-limiting steps for transfection mediated by . and it is known to enhance the transcytosis of viral vector [158.8 chitosan aiming to achieve liver target delivery.3. while dextran was grafted to enhance the stability of the complex in aqueous media. Results of transfection studies showed that folate-chitosan-based nanoparticles enhanced the reporter gene expression against a cell line overexpressing FR (SKOV3 cells) compared to an FR-deﬁcient cell line (A549 cells) and did not induce obvious cytotoxicity against HEK 293 cells . Conjugation of Protein Ligands. 152]. 5. and the nonepithelial isoform of FR (FRb) is expressed on activated synovial macrophages present in large numbers in arthritic joints . Folate receptor (FR) is over-expressed on many human cancer cell surfaces. Tf-conjugated nanoparticles invariably showed threefold greater transfection eﬃciency than unmodiﬁed nanoparticles. 159].
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The IRS released the 2017 draft forms and instructions for the ACA employer reporting requirement. The 2017 draft forms and instructions are very similar to those used for 2016. Given that they have only minor changes (along with a few clarifications of existing requirements), the most significant change is the deletion throughout of anything referring to §4980H transition relief, which is expired and no longer applicable.
Under §6056, all applicable large employers (ALEs) – those averaging 50 or more full-time equivalents (FTEs) in the previous calendar year – must report information about the health care coverage offered to full-time employees using Forms 1094-C and 1095-C. Reporting is required regardless of whether coverage was actually offered; and if offered, regardless of whether the coverage is fully insured or self-funded. The IRS uses this information to administer the employer shared responsibility provisions under §4980H and the premium tax credits available to some individuals who choose to purchase coverage through a public Exchange.
Under §6055, all employers offering a self-funded group health plan considered to be minimum essential coverage (MEC) must report information about the individuals actually covered under the plan. If an ALE offers a self-funded group health plan, all information required under §§6055 and 6056 will generally be reported using Forms 1094-C and 1095-C. If a small employer (fewer than 50 FTEs) offers a self-funded group health plan, coverage information will be reported using Forms 1094-B and 1095-B. For fully insured plans, this information will be reported by the insurance carrier using Forms 1094-B and 1095-B. The IRS uses this information to enforce the individual mandate requirements.
The instructions clarify that there is no specific code to indicate a waiver of coverage on Line 16 of Form 1095-C. If a full-time employee is offered coverage and waives it, generally the employer should enter the applicable affordability safe harbor (i.e., Code 2F, 2G, or 2H) or leave it blank.
The applicable affordability percentage for 2017 is 9.69%.
In general, most §4980H transition relief was applicable only for 2015 (as well as for a portion of 2016 for non-calendar year plans). In 2017, no further transition relief was available for ALEs required to comply with §4980H, and therefore Box C is marked as “Reserved.” In addition, Part III, column (e) is marked as “Reserved.” This change may simplify reporting slightly in that many employers found reporting for applicable §4980H transition relief confusing.
Inadvertent errors in reporting the required employee contribution on Line 15 of Form 1095-C may not require correction so long as the amount is de minimis (i.e., within $100 (annually) of the correct amount). See details in Notice 2017-9 found at https://www.irs.gov/pub/irs-drop/n-17-09.pdf. NOTE – Individuals receiving the Form 1095-C must be allowed the opportunity to request a corrected statement if they wish to do so. If a corrected form is not provided upon request, then standard penalties may apply.
An updated address was provided for those persons who elect to mail hard-copy forms to Kansas City, MO (the address for those required to mail forms to Austin, TX is unchanged). This includes employers based in Alaska, California, Oregon and Washington.
The instructions also clarify that forms must be printed in landscape format.
The penalty amount caps were raised slightly for 2017, remaining at $260 per form, but capped at $3,218,500 annually (up from $3,193,000 in 2016).
There are not any major changes to the draft forms or the instructions that alter how or when employer reporting is to be completed. The forms themselves are almost identical. It seems unlikely that we will see any further changes of significance once the final forms and instructions are released. Without any legislation- or regulation-changing employer reporting obligations, we recommend that all ALEs and employers offering self-funded plans begin employer reporting preparations sooner rather than later in order to meet deadlines in early 2018.
The draft forms and instructions may be found on the IRS draft forms website at https://apps.irs.gov/app/picklist/list/draftTaxForms.html. Just enter 1095 in the search box.
As always, should you have any questions, please contact your Parker, Smith & Feek Benefits Team.
While every effort has been taken in compiling this information to ensure that its contents are totally accurate, neither the publisher nor the author can accept liability for any inaccuracies or changed circumstances of any information herein or for the consequences of any reliance placed upon it. This publication is distributed on the understanding that the publisher is not engaged in rendering legal, accounting or other professional advice or services. Readers should always seek professional advice before entering into any commitments.


text:
CLAUDIA GREENFIELD & another vs. ABNER L. FREEDMAN.
Evidence did not warrant a finding that a storekeeper was negligent in failing to warn a woman customer on his premises in October that the edges of outdoor walks thereon had edgestones and were covered by leaves, or, having furnished paths in the walks clear of leaves to a suitable width for her use, in failing to clear the leaves from the entire width of the walks or to anticipate that she would "cut through the heaped-up leaves" near the junction of the edges of two walks as she was doing when her foot struck something hard under the leaves and she fell.
TORT. Writ in the Superior Court dated December 4, 1947. The action was tried before Beaudreau, J. R. B. Coulter, (P. S. Ratzkoff with him,) for the defendant. F. J. Monahan, (D. H. Gordon with him,) for the plaintiffs.
RONAN, J. This is an action of tort seeking in one count to recover for personal injuries sustained by the female plaintiff when she fell on the defendant's premises and seeking in another count consequential damages by her husband. The jury returned a verdict for each plaintiff. The defendant excepted to the denial of his motion to enter verdicts in accordance with leave reserved.
The defendant conducted a decorating studio in which he sold furniture in the front of the first floor of a building. There was a show window on either side of the entrance. The building set back eighteen to twenty feet from the public sidewalk. A concrete walk led from the sidewalk to the entrance, and as this center walk approached the entrance it was flanked on either side by a short walk which extended from the center walk beyond and in front of each show window. The female plaintiff, hereinafter called the plaintiff, entered the store by means of the center walk leading from the street. It was shortly after sunset upon a pleasant October afternoon. She had no difficulty in seeing the surface condition of the defendant's premises. As she travelled along the center walk from the street she noticed that, with the exception of a few scattered leaves, there was a clear space two to three feet wide along the middle of this walk and that upon both sides of this clearing leaves were piled up ten to twelve inches high. She also observed the walk in front of each window. She could not see whether there was any edgestone or brick edging by the outer edges of any of these walks. She left the store after a short visit and went to her right a few steps to look at the articles in that window. She saw that there was a clear path about a foot and one half wide along the middle of that walk and that leaves tapered up from the street edge of this clearing to ten inches in height. She left the window, turned around, walked back at a slight diagonal, and "cut through the heaped-up leaves," intending to reach the center walk and to go along that walk to the street, when her foot struck something hard under the "heaped-up leaves" in the vicinity of where the outer edges of side and center walks met and she was thrown down.
There were two large trees on the street in front of the store. The branches of one of them extended almost to the store. There were other trees close by in the street. There had been a heavy shedding of leaves.
were exhibited for sale and, as she testified, to purchase a particular article which it turned out the defendant did not have in stock. She was a business visitor of the defendant not only while in the store but also while looking in the window and in fact while entering and leaving his premises along the walks designated for the use of his customers. The storekeeper was obliged to exercise reasonable care to keep in a safe condition that part of his premises to which customers were invited or at least to warn them against any dangers, not known to them nor obvious to an ordinarily intelligent person, which were either known or ought to have been known to the storekeeper. Kelley v. Goldberg, 288 Mass. 79. Heina v. Broadway Fruit Market, Inc. 304 Mass. 608. Rouillard v. Canadian Klondike Club, Inc. 316 Mass. 11. Tetrault v. Ghibellini, 316 Mass. 477. Staples v. Pond Club, Inc. 319 Mass. 238.
There was no evidence that the center walk and the short walk in front of the window were not properly constructed or that they contained any defect or were out of repair. If they had an edgestone by their outer edge, as the husband's testimony seemed to indicate there was, where his wife fell, there was nothing whatever to show that the edgestone was not of such usual type of construction that no warning from the defendant was necessary to apprise her that the walks had an edgestone like many other walks. Hunnewell v. Haskell, 174 Mass. 557. Adduci v. Boston Elevated Railway, 215 Mass. 336. Perkins v. Bay State Street Railway, 223 Mass. 235. Coleman v. Boston Elevated Railway, 249 Mass. 155.
of the window where the middle portions of both walks were open and obvious and almost bare of leaves. She had no difficulty in travelling along these parts of the walks. They were adequate and safe for her use. The defendant was not required to furnish more extensive and wider means of ingress and egress. Neither was there anything in the appearance that invited her to leave the middle path of either walk and to travel over parts that were covered with leaves. The leaves were not shown to have been wet or slippery and were not an active factor in causing the accident. They did not constitute a defect. See Osborne v. North Tarrytown, 180 App. Div. (N. Y.) 224. At most their presence was transitory. See Whittaker v. Bent, 167 Mass. 588; Kralik v. LeClair, 315 Mass. 323. If we assume that the defendant knew or ought to have known that leaves had fallen and remained upon the walks, we do not think that, an area suitable for the use of customers having been furnished by the defendant, he was also obliged constantly to keep the whole width of the walks free from all leaves which the evidence tended to show were falling thickly upon his premises.
Failure to warn the plaintiff that the outer portions of the walks, including their outside edges, were covered with leaves was not evidence of negligence. Neither do we think that he should have reasonably anticipated that the plaintiff would cut across diagonally through the leaves from one walk to another. To impose liability upon the defendant in these circumstances "would be to establish an unreasonable standard of perfection rather than to enforce the recognized standard of due care." Rogers v. Cambridge Taxi Co. 317 Mass. 578, 580. See Towne v. Waltham Watch Co. 247 Mass. 390; Gagnon v. DiVittorio, 310 Mass. 475; Marengo v. Roy, 318 Mass. 719; Shaner v. Imperial Motor Sales, Inc. 323 Mass. 755; MacGillivray v. First National Stores Inc. 326 Mass. 678.

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1.1 Responsible for the data processing on this website within the meaning of the General Data Protection Regulation (GDPR) is Bianca Greuel, SoftCreatR Media, Roßheidestr. 149, 45968 Gladbeck, Germany, Tel.: +49 (0) 2043 374918, Fax: +49 (0) 2043 9424940, E-Mail: info@softcreatr.de. The person responsible for the processing of personal data is the natural or legal person who, alone or together with others, decides on the purposes and means of processing personal data.
1.2 This website uses SSL or TLS encryption for security reasons and to protect the transmission of personal data and other confidential content (e. g. orders or enquiries to the responsible person). You can recognize an encrypted connection by the string "https" and the lock icon in your browser line.
The processing is carried out in accordance with Art. 6 para. 1 lit. f GDPR based on our legitimate interest in improving the stability and functionality of our website. The data will not be passed on or used in any other way. However, we reserve the right to subsequently check the server log files if there are concrete indications of illegal use.
On our website we use a so-called Content Delivery Network ("CDN") of the technology service provider Netlify Inc., 2325 3rd Street, Suite 215, San Francisco, CA 94107, USA ("Netlify"). A content delivery network is an online service used to deliver large media files (such as graphics, page content or scripts) through a network of regionally distributed connected via the Internet. Using Netlify's Content Delivery Network helps us to optimize the loading speeds of our website.
The processing is carried out in accordance with Art. 6 para. 1 lit. f GDPR based on our legitimate interest in a secure and efficient deployment, as well as the improvement of the stability and functionality of our website.
In some cases, cookies are used to simplify the ordering process by saving settings (e.g. remembering the contents of a virtual shopping cart for a later visit of the website). If individual cookies implemented by us are also processed with personal data, the processing is carried out in accordance with Art. 6 para. 1 lit. b GDPR either to fulfill the contract or in accordance with Art. 6 para. 1 lit. f GDPR for safeguarding our legitimate interests in the best possible functionality of the website as well as a customer-friendly and effective design of the page visit.
We may work with advertising partners to help us make our web site more interesting to you. For this purpose when you visit our website, cookies from partner companies are stored on your hard disk (third-party cookies). If we cooperate with the aforementioned advertising partners, you will be informed individually and separately about the use of such cookies and the scope of the collected informations within the following paragraphs.
When contacting us (e.g. via contact form or email), personal data is collected. Which data are collected in the case of a contact form can be seen from the respective contact form. These data are stored and used exclusively for the purpose of answering your request or for establishing contact and the associated technical administration. The legal basis for processing the data is our legitimate interest in answering your request in accordance with Art. 6 para. 1 lit. f GDPR. If your contact is aimed at concluding a contract, then additional legal basis for the processing is Art. 6 para. 1 lit. b GDPR. Your data will be deleted after final processing of your request, this is the case if the circumstances indicate that the matter in question has been conclusively clarified and if there are no legal obligations to retain data to the contrary.
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In particular, you have the right to obtain information about the personal data processed by us, the processing purposes, the categories of processed personal data, the recipients or categories of recipients to whom your data has been disclosed, or the planned Period of storage or the criteria for determining the duration of storage, the right of rectification, deletion, limitation of processing, objection to processing, complaint to a supervisory authority, the origin of your data, if they were not collected by us, the existence of automated decision-making including profiling and possibly meaningful information about the logic and scope involved and the intended effects of such processing, as well as your right to be informed, which guarantees pursuant to Art. 46 GDPR for redirection I data in third countries.
You have the right to immediate correction of incorrect data concerning you and/or completion of your incomplete data stored by us.
You have the right to demand the deletion of your personal data if the requirements of Art. 17 para. 1 GDPR are met. However, that right does not apply, in particular, where the processing is necessary for the exercise of the right to freedom of expression and information, for the fulfillment of a legal obligation, for reasons of public interest or for the pursuit, exercise or defense of rights.
You have the right to demand the restriction of the processing of your personal data, as long as the correctness of your data, which is disputed by you, is reviewed, if you refuse deletion of your data due to inadmissible data processing and instead Restricting the processing of your data require, if you need your data for the assertion, exercise or defense of legal rights, after we no longer need these data after purpose or if you have objected for reasons of your particular situation, as long as it is not certain, whether our entitled reasons prevail.
If you have the right to rectify, delete or limit the processing to the person responsible, he/she is obligated to rectify or delete the data or all recipients to whom the personal data relating to you have been disclosed Notify of limitation of the processing, unless this proves to be impossible or involves a disproportionate effort. You have the right to be informed about these recipients.
You have the right to receive your personal data provided to us in a structured, common and machine-readable format or to request transmission to another person responsible, as far as this is technically feasible.
You have the right to revoke consent once given in the processing of data at any time with effect for the future. In the case of withdrawal, we will delete the data concerned immediately, as far as further processing can not be based on a legal basis for consentless processing. The revocation of consent does not affect the lawfulness of the processing carried out on the basis of the consent until the revocation.
If you consider that the processing of your personal data violates the GDPR, you have the right to complain to a supervisory authority, in particular in the case of an administrative or judicial remedy Member State of your whereabouts, place of work or place of alleged infringement.

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