Therapeutic Management of Malignant Wounds: An Update.

OPINION STATEMENT: Malignant fungating wounds (MFW) are severe skin conditions generating tremendous distress in oncological patients with advanced cancer stages because of pain, malodor, exudation, pruritus, inflammation, edema, and bleeding. The classical therapeutic approaches such as surgery, opioids, antimicrobials, and application of different wound dressings are failing in handling pain, odor, and infection control, thus urgently requiring the development of alternative strategies. The aim of this review was to provide an update on the current therapeutic strategies and the perspectives on developing novel alternatives for better malignant wound management. The last decade screened literature evidenced an increasing interest in developing natural treatment alternatives based on beehive, plant extracts, pure vegetal compounds, and bacteriocins. Promising therapeutics can also be envisaged by involving nanotechnology due to either intrinsic biological activities or drug delivery properties of nanomaterials. Despite recent progress in the field of malignant wound care, the literature is still mainly based on in vitro and in vivo studies on small animal models, while the case reports and clinical trials (less than 10 and only one providing public results) remain scarce. Some innovative treatment approaches are used in clinical practice without prior extensive testing in fungating wound patients. Extensive research is urgently needed to fill this knowledge gap and translate the identified promising therapeutic approaches to more advanced testing stages toward creating multidimensional wound care strategies.

New Library of Iodo-Quinoline Derivatives Obtained by an Alternative Synthetic Pathway and Their Antimicrobial Activity.

6-Iodo-substituted carboxy-quinolines were obtained using a one-pot, three-component method with trifluoroacetic acid as a catalyst under acidic conditions. Iodo-aniline, pyruvic acid and 22 phenyl-substituted aldehydes (we varied the type and number of radicals) or O-heterocycles, resulting in different electronic effects, were the starting components. This approach offers advantages such as rapid response times, cost-effective catalysts, high product yields and efficient purification procedures. A comprehensive investigation was conducted to examine the impact of aldehyde structure on the synthesis pathway. A library of compounds was obtained and characterized by FT-IR, MS, 1H NMR and 13C NMR spectroscopy and single-ray crystal diffractometry. Their antimicrobial activity against S. epidermidis, K. pneumonie and C. parapsilosis was tested in vitro. The effect of iodo-quinoline derivatives on microbial adhesion, the initial stage of microbial biofilm development, was also investigated. This study suggests that carboxy-quinoline derivatives bearing an iodine atom are interesting scaffolds for the development of novel antimicrobial agents.

Dextran Formulations as Effective Delivery Systems of Therapeutic Agents.

Dextran is by far one of the most interesting non-toxic, bio-compatible macromolecules, an exopolysaccharide biosynthesized by lactic acid bacteria. It has been extensively used as a major component in many types of drug-delivery systems (DDS), which can be submitted to the next in-vivo testing stages, and may be proposed for clinical trials or pharmaceutical use approval. An important aspect to consider in order to maintain high DDS' biocompatibility is the use of dextran obtained by fermentation processes and with a minimum chemical modification degree. By performing chemical modifications, artefacts can appear in the dextran spatial structure that can lead to decreased biocompatibility or even cytotoxicity. The present review aims to systematize DDS depending on the dextran type used and the biologically active compounds transported, in order to obtain desired therapeutic effects. So far, pure dextran and modified dextran such as acetalated, oxidised, carboxymethyl, diethylaminoethyl-dextran and dextran sulphate sodium, were used to develop several DDSs: microspheres, microparticles, nanoparticles, nanodroplets, liposomes, micelles and nanomicelles, hydrogels, films, nanowires, bio-conjugates, medical adhesives and others. The DDS are critically presented by structures, biocompatibility, drugs loaded and therapeutic points of view in order to highlight future therapeutic perspectives.

Electrochemical Sensor for Tryptophan Determination Based on Trimetallic-CuZnCo-Nanoparticle-Modified Electrodes.

The superior properties of electrodeposited trimetallic CuZnCo nanoparticles, arising from the synergistic effect of combining the unique features of metallic components, were confirmed using voltametric measurements. The surface morphology and structure of the as-prepared electrocatalysts were determined using scanning electron microscopy, energy-dispersive X-ray, and X-ray photoelectron spectroscopy techniques. Here, the trimetallic CuZnCo nanoparticles were synthesized as a powerful redox probe and highly efficient signal amplifier for the electrochemical oxidation of tryptophan. Differential pulse voltammetry studies showed a linear relationship with a tryptophan concentration of 5-230 µM, and the low detection limit was identified at 1.1 µM with a sensitivity of 0.1831 µA µM-1 cm-2.

Towards Regenerative Audiology: Immune Modulation of Adipose-Derived Mesenchymal Cells Preconditioned with Citric Acid-Coated Antioxidant-Functionalized Magnetic Nanoparticles.

Introduction and Background: Based on stem cells, bioactive molecules and supportive structures, regenerative medicine (RM) is promising for its potential impact on field of hearing loss by offering innovative solutions for hair cell rescue. Nanotechnology has recently been regarded as a powerful tool for accelerating the efficiency of RM therapeutic solutions. Adipose-derived mesenchymal cells (ADSCs) have already been tested in clinical trials for their regenerative and immunomodulatory potential in various medical fields; however, the advancement to bedside treatment has proven to be tedious. Innovative solutions are expected to circumvent regulatory and manufacturing issues related to living cell-based therapies. The objectives of the study were to test if human primary ADSCs preconditioned with magnetic nanoparticles coated with citric acid and functionalized with antioxidant protocatechuic acid (MNP-CA-PCA) retain their phenotypic features and if conditioned media elicit immune responses in vitro. MNP-CA-PCA was synthesized and characterized regarding size, colloidal stability as well as antioxidant release profile. Human primary ADSCs preconditioned with MNP-CA-PCA were tested for viability, surface marker expression and mesenchymal lineage differentiation potential. Conditioned media (CM) from ADSCs treated with MNP-CA-PCA were tested for Il-6 and IL-8 cytokine release using ELISA and inhibition of lectin-stimulated peripheral blood monocyte proliferation. Results: MNP-CA-PCA-preconditioned ADSCs display good viability and retain their specific mesenchymal stem cell phenotype. CM from ADSCs conditioned with MNP-CA-PCA do not display increased inflammatory cytokine release and do not induce proliferation of allergen-stimulated allogeneic peripheral blood monocytes in vitro. Conclusions: While further in vitro and in vivo tests are needed to validate these findings, the present results indicated that CM from ADSCs preconditioned with MNP-CA-PCA could be developed as possible cell-free therapies for rescuing auditory hair cells.

Innovative Non-Enzymatic Electrochemical Quantification of Cholesterol.

The use of the Liebermann-Burchard reaction in this study has been explored in the development of a simple, reliable, and robust quantitative electrochemical method to assay cholesterol, and hence provide a good alternative to colorimetric methods. The optimization of batch mode operation for electrochemical oxidation of cholesterol in the Liebermann-Burchard reagents included the applied potential and acidic volume. Tested using chronoamperometry, the developed method showed a high sensitivity (14.959 µA mM-1) and low detection limit (19.78 nM) over a 0.025-3 mM concentration range, with remarkable linearity (R2 = 0.999), proving an analytical performance either higher or comparable to most of the cholesterol sensors discussed in literature. The influence of possible interfering bioactive agents, namely, glucose, uric acid, ascorbic acid, KCl and NaCl, has been evaluated with no or negligible effects on the measurement of cholesterol. Our study was directed at finding a new approach to chemical processing arising from the use of external potential as an additional level of control for chemical reactions and the transfer of electrons between surfaces and molecules. Finally, the optimized method was successfully applied for the determination of cholesterol content in real blood samples.

Quantification of Low Amounts of Zoledronic Acid by HPLC-ESI-MS Analysis: Method Development and Validation.

Zoledronic acid (ZA) is used in the treatment of various bone pathologies, but it forms complexes with calcium ions present in body fluids, decreasing ZA bioavailability. Thereby, the study first describes the identification of ZA-calcium complexes that form in calcium-rich environments, in order to establish the bioavailable ZA concentration. Then, a new method for quantification of low ZA amounts in milieus that mimics in vivo conditions by using simulated body fluid and calcium sulfate hemihydrate was described. Almost all analytical methods of ZA quantification described in the literature require compound derivatization. At very low concentrations, derivatization is prone to analyte loss, therefore compromising the analytical results. In our study, we avoided ZA derivatization by using a high-performance liquid chromatography and electrospray ionization mass spectrometry (HPLC-ESI-MS) system, conducting the investigation based on the fragmentation mass extracted ion chromatograms specific to the ZA protonated form. The method was validated by selectivity, precision, accuracy, linearity, signal to noise ratio, and limit of detection and limit of quantification calculation. Experimentally, this method can detect ranges of 0.1-0.5 ng/mL and precisely quantify ZA concentrations as low as 0.1 ng/mL. This method could provide the basis for quantifying low amounts of ZA in the blood during long-term administration.

VCAM-1 Targeted Lipopolyplexes as Vehicles for Efficient Delivery of shRNA-Runx2 to Osteoblast-Differentiated Valvular Interstitial Cells; Implications in Calcific Valve Disease Treatment.

Calcific aortic valve disease (CAVD) is a progressive inflammatory disorder characterized by extracellular matrix remodeling and valvular interstitial cells (VIC) osteodifferentiation leading to valve leaflets calcification and impairment movement. Runx2, the master transcription factor involved in VIC osteodifferentiation, modulates the expression of other osteogenic molecules. Previously, we have demonstrated that the osteoblastic phenotypic shift of cultured VIC is impeded by Runx2 silencing using fullerene (C60)-polyethyleneimine (PEI)/short hairpin (sh)RNA-Runx2 (shRunx2) polyplexes. Since the use of polyplexes for in vivo delivery is limited by their instability in the plasma and the non-specific tissue interactions, we designed and obtained targeted, lipid-enveloped polyplexes (lipopolyplexes) suitable for (1) systemic administration and (2) targeted delivery of shRunx2 to osteoblast-differentiated VIC (oVIC). Vascular cell adhesion molecule (VCAM)-1 expressed on the surface of oVIC was used as a target, and a peptide with high affinity for VCAM-1 was coupled to the surface of lipopolyplexes encapsulating C60-PEI/shRunx2 (V-LPP/shRunx2). We report here that V-LPP/shRunx2 lipopolyplexes are cyto- and hemo-compatible and specifically taken up by oVIC. These lipopolyplexes are functional as they downregulate the Runx2 gene and protein expression, and their uptake leads to a significant decrease in the expression of osteogenic molecules (OSP, BSP, BMP-2). These results identify V-LPP/shRunx2 as a new, appropriately directed vehicle that could be instrumental in developing novel strategies for blocking the progression of CAVD using a targeted nanomedicine approach.

Tellurides bearing benzensulfonamide as carbonic anhydrase inhibitors with potent antitumor activity.

We evaluated in vitro a series of telluride containing compounds bearing the benzenesulfonamide group, as effective inhibitors of the physiologically relevant human (h) expressed Carbonic Anhydrase (CA; EC 4.2.1.1) enzymes I, II, IV VII and IX. The potent effects of such compounds against the tumor-associated hCA IX being low nanomolar inhibitors (KI 2.2 to 2.9 nM) and with good selectivity over the ubiquitous hCA II, gave the possibility to evaluate their lethal effect in vitro against a breast cancer cell line (MDA-MB-231). Among the series, both compounds 3a and 3g induced significant toxic effects against tumor cells after 48 h incubation. Under normoxic condition 3a showed high efficacy killing over 94% of tumor cells at 1 µM, and derivative 3g reached the tumor cell viability under the 5% at 10 µM. In hypoxic condition, these two compounds showed less effective although retained excellent cancer cell killer. These unusual features make them interesting lead compounds acting as antitumor agents also in tumor types not dependent from hCA IX overexpression.

Chromene-Containing Aromatic Sulfonamides with Carbonic Anhydrase Inhibitory Properties.

Carbonic anhydrases (CAs, EC 4.2.1.1) catalyze the essential reaction of CO2 hydration in all living organisms, being actively involved in the regulation of a plethora of patho/physiological conditions. A series of chromene-based sulfonamides were synthesized and tested as possible CA inhibitors. Their inhibitory activity was assessed against the cytosolic human isoforms hCA I, hCA II and the transmembrane hCA IX and XII. Several of the investigated derivatives showed interesting inhibition activity towards the tumor associate isoforms hCA IX and hCA XII. Furthermore, computational procedures were used to investigate the binding mode of this class of compounds, within the active site of hCA IX.

SI-ATRP Decoration of Magnetic Nanoparticles with PHEMA and Post-Polymerization Modification with Folic Acid for Tumor Cells' Specific Targeting.

Targeted nanocarriers could reach new levels of drug delivery, bringing new tools for personalized medicine. It is known that cancer cells overexpress folate receptors on the cell surface compared to healthy cells, which could be used to create new nanocarriers with specific targeting moiety. In addition, magnetic nanoparticles can be guided under the influence of an external magnetic field in different areas of the body, allowing their precise localization. The main purpose of this paper was to decorate the surface of magnetic nanoparticles with poly(2-hydroxyethyl methacrylate) (PHEMA) by surface-initiated atomic transfer radical polymerization (SI-ATRP) followed by covalent bonding of folic acid to side groups of the polymer to create a high specificity magnetic nanocarrier with increased internalization capacity in tumor cells. The biocompatibility of the nanocarriers was demonstrated by testing them on the NHDF cell line and folate-dependent internalization capacity was tested on three tumor cell lines: MCF-7, HeLa and HepG2. It has also been shown that a higher concentration of folic acid covalently bound to the polymer leads to a higher internalization in tumor cells compared to healthy cells. Last but not least, magnetic resonance imaging was used to highlight the magnetic properties of the functionalized nanoparticles obtained.

Raman Spectroscopy, X-ray Diffraction, and Scanning Electron Microscopy as Noninvasive Methods for Microstructural Alterations in Psoriatic Nails.

Psoriasis is a chronic inflammatory disease associated with immune system dysfunction that can affect nails, with a negative impact on patient life quality. Usually, nail psoriasis is associated with skin psoriasis and is therefore relatively simple to diagnose. However, up to 10% of nail psoriasis occurs isolated and may be difficult to diagnose by means of current methods (nail biopsy, dermoscopy, video dermoscopy, capillaroscopy, ultrasound of the nails, etc.). Since the nail is a complex biological tissue, mainly composes of hard α-keratins, the structural and morphological techniques can be used to analyze the human fingernails. The aim of this study was to corroborate the information obtained using Raman spectroscopy with those obtained by scanning electron microscopy (SEM) and X-ray diffractometry and to assess the potential of these techniques as non-invasive dermatologic diagnostic tools and an alternative to current methods.

Carbonic Anhydrase Inhibition with Sulfonamides Incorporating Pyrazole- and Pyridazinecarboxamide Moieties Provides Examples of Isoform-Selective Inhibitors.

A series of benzenesulfonamides incorporating pyrazole- and pyridazinecarboxamides decorated with several bulky moieties has been obtained by original procedures. The new derivatives were investigated for the inhibition of four physiologically crucial human carbonic anhydrase (hCA, EC 4.2.2.1.1) isoforms, hCA I and II (cytosolic enzymes) as well as hCA IX and XII (transmembrane, tumor-associated isoforms). Examples of isoform-selective inhibitors were obtained for all four enzymes investigated here, and a computational approach was employed for explaining the observed selectivity, which may be useful in drug design approaches for obtaining inhibitors with pharmacological applications useful as antiglaucoma, diuretic, antitumor or anti-cerebral ischemia drugs.

Antibacterial Polysiloxane Polymers and Coatings for Cochlear Implants.

Within this study, new materials were synthesized and characterized based on polysiloxane modified with different ratios of N-acetyl-l-cysteine (NAC) and crosslinked via UV-assisted thiol-ene addition, in order to obtain efficient membranes able to resist bacterial adherence and biofilm formation. These membranes were subjected to in vitro testing for microbial adherence against S. pneumoniae using standardized tests. WISTAR rats were implanted for 4 weeks with crosslinked siloxane samples without and with NAC. A set of physical characterization methods was employed to assess the chemical structure and morphological aspects of the new synthetized materials before and after contact with the microbiological medium.

Chitosan Derivatives in Macromolecular Co-assembly Nanogels with Potential for Biomedical Applications.

Maleoyl-chitosan/poly(aspartic acid) nanogels were developed and characterized in order to assess its suitability for biomedical applications. Thus, the physicochemical properties were investigated and correlated with the composition of the new structures. Dynamic light scattering measurements, correlated with transmission electron microscopy images, demonstrated that nanogels size distribution was narrow with average diameter between 186 and 246 nm, and presented positive zeta potential values. The sensitivity of nanogels at pH and temperature was also evaluated. Nanogels loaded with amoxicillin showed a controlled release profile dependent on nanogel content. The formulations loaded with amoxicillin had antibacterial properties, and the cytotoxicity tests indicated good in vivo biocompatibility. In conclusion, the new synthesized polyelectrolyte nanogels, which can provide a stable environment for the encapsulated drugs, can be used as a multifunctional platform for administration of antimicrobial agents from the spectrum of antibiotics that have a very poor biodistribution.

Cytotoxic substituted indolizines as new colchicine site tubulin polymerisation inhibitors.

A potential microtubule destabilising series of new indolizine derivatives was synthesised and tested for their anticancer activity against a panel of 60 human cancer cell lines. Compounds 11a, 11b, 15a, and 15j showed a broad spectrum of growth inhibitory activity against cancer cell lines representing leukaemia, melanoma and cancer of lung, colon, central nervous system, ovary, kidney, breast, and prostate. Among them, compound 11a was distinguishable by its excellent cytostatic activity, showing GI50 values in the range of 10-100 nM on 43 cell lines. The less potent compounds 15a and 15j in terms of GI50 values showed a high cytotoxic effect against tested colon cancer, CNS cancer, renal cancer and melanoma cell lines and only on few cell lines from other types of cancer. In vitro assaying revealed tubulin polymerisation inhibition by all active compounds. Molecular docking showed good complementarity of active compounds with the colchicine binding site of tubulin.

Sulfonamide Inhibition Studies of an α-Carbonic Anhydrase from Schistosoma mansoni, a Platyhelminth Parasite Responsible for Schistosomiasis.

Schistosomiasis is a debilitating infection provoked by parasitic flatworms called schistosomes. The species Schistosoma mansoni is endemic in Africa, where it causes intestinal schistosomiasis. Recently, an α-carbonic anhydrase (CA, EC 4.2.1.1) was cloned and characterized from this organism and designated as SmCA. The protein is expressed in the tegument (skin) of S. mansoni at the host-parasite interface. Recombinant SmCA possesses high catalytic activity in the CO2 hydration reaction, similar to that of human CA isoform II with a kcat of 1.2 × 106 s-1 and a kcat/KM of 1.3 × 108 M-1·s-1. It has been found that schistosomes whose SmCA gene is suppressed using RNA interference are unable to establish a robust infection in mice, suggesting that the chemicals that inhibit SmCA function should have the same debilitating effect on the parasites. In this study, a collection of aromatic/heterocyclic sulfonamides were investigated as possible SmCA inhibitors. Several sulfonamides inhibited SmCA with medium to weak potency (KI values of 737.2 nM-9.25 µM), whereas some heterocyclic compounds inhibited the enzyme with KI values in the range of 124-325 nM. The α-CA from S. mansoni, SmCA, is proposed as a new anti-schistosomiasis drug target.

Evaluation of Thio- and Seleno-Acetamides Bearing Benzenesulfonamide as Inhibitor of Carbonic Anhydrases from Different Pathogenic Bacteria.

A series of 2-thio- and 2-seleno-acetamides bearing the benzenesulfonamide moiety were evaluated as Carbonic Anhydrase (CA, EC 4.2.1.1) inhibitors against different pathogenic bacteria such as the Vibrio cholerae (VchCA-α and VchCA-ß), Burkholderia pseudomallei (BpsCA-ß and BpsCA-γ), Mycobacterium tuberculosis (Rv3723-ß) and the Salmonella enterica serovar Typhimurium (StCA2-ß). The molecules represent interesting leads worth developing as innovative antibacterial agents since they possess new mechanism of action and isoform selectivity preferentially against the bacterial expressed CAs. The identification of potent and selective inhibitors of bacterial CAs may lead to tools also useful for deciphering the physiological role(s) of such proteins.

Crystal Structure of a Tetrameric Type II ß-Carbonic Anhydrase from the Pathogenic Bacterium Burkholderia pseudomallei.

Carbonic anhydrase (CA) is a zinc enzyme that catalyzes the reversible conversion of carbon dioxide to bicarbonate and proton. Currently, CA inhibitors are widely used as antiglaucoma, anticancer, and anti-obesity drugs and for the treatment of neurological disorders. Recently, the potential use of CA inhibitors to fight infections caused by protozoa, fungi, and bacteria has emerged as a new research line. In this article, the X-ray crystal structure of ß-CA from Burkholderia pseudomallei was reported. The X-ray crystal structure of this new enzyme was solved at 2.7 Å resolution, revealing a tetrameric type II ß-CA with a "closed" active site in which the zinc is tetrahedrally coordinated to Cys46, Asp48, His102, and Cys105. B. pseudomallei is known to encode at least two CAs, a ß-CA, and a γ-CA. These proteins, playing a pivotal role in its life cycle and pathogenicity, offer a novel therapeutic opportunity to obtain antibiotics with a different mechanism of action. Furthermore, the new structure can provide a clear view of the ß-CA mechanism of action and the possibility to find selective inhibitors for this class of CAs.

On the Charge-Transfer Excitations in Azobenzene Maleimide Compounds: A Theoretical Study.

Photoswitchable systems with charge-transfer (CT) transitions have gained much attention during the recent years because of their many emerging applications. CT transitions themselves are of fundamental importance from physical, chemical, engineering, and molecular modeling points of view because they depend on the modified intramolecular electronic structure. CT transitions in azobenzene (AB) were observed when substituted with the maleimide (MI) functional group. This work represents a systematic theoretical study of excited states of the AB-MI structures of eight azo derivatives. In addition to the two main azo transitions (π → π* and n → π*), our calculations show a CT occurring between the azo moiety as a donor and the MI group as an acceptor. The CT mechanism can be characterized based on both the number and the position of the MI fragments. MI groups in the azo structure result in low-energy transitions, changing the order of the main transitions by introducing a CT character. Calculations using both density functional theory (DFT) and high-end molecular orbital theories confirm the CT character of these derivatives, although the order of excited states was found to differ depending on the chosen level of theory. We present here the first theoretical investigation of the electronic excited states (nπ*CT and ππ*CT) and corresponding transitions for this class of compounds. The computational results showed that the CT mechanism in AB-MI derivatives can occur via two pathways: planar and twisted. Our findings are expected to be of substantial interest, especially in the area of molecular optoelectronics and in the design of responsive materials.