Biocompatible glyconanomaterials based on HPMA-copolymer for specific targeting of galectin-3.

BACKGROUND: Galectin-3 (Gal-3) is a promising target in cancer therapy with a high therapeutic potential due to its abundant localization within the tumor tissue and its involvement in tumor development and proliferation. Potential clinical application of Gal-3-targeted inhibitors is often complicated by their insufficient selectivity or low biocompatibility. Nanomaterials based on N-(2-hydroxypropyl)methacrylamide (HPMA) nanocarrier are attractive for in vivo application due to their good water solubility and lack of toxicity and immunogenicity. Their conjugation with tailored carbohydrate ligands can yield specific glyconanomaterials applicable for targeting biomedicinally relevant lectins like Gal-3. RESULTS: In the present study we describe the synthesis and the structure-affinity relationship study of novel Gal-3-targeted glyconanomaterials, based on hydrophilic HPMA nanocarriers. HPMA nanocarriers decorated with varying amounts of Gal-3 specific epitope GalNAcß1,4GlcNAc (LacdiNAc) were analyzed in a competitive ELISA-type assay and their binding kinetics was described by surface plasmon resonance. We showed the impact of various linker types and epitope distribution on the binding affinity to Gal-3. The synthesis of specific functionalized LacdiNAc epitopes was accomplished under the catalysis by mutant ß-N-acetylhexosaminidases. The glycans were conjugated to statistic HPMA copolymer precursors through diverse linkers in a defined pattern and density using Cu(I)-catalyzed azide-alkyne cycloaddition. The resulting water-soluble and structurally flexible synthetic glyconanomaterials exhibited affinity to Gal-3 in low µM range. CONCLUSIONS: The results of this study reveal the relation between the linker structure, glycan distribution and the affinity of the glycopolymer nanomaterial to Gal-3. They pave the way to specific biomedicinal glyconanomaterials that target Gal-3 as a therapeutic goal in cancerogenesis and other disorders.

[Anti-inflammatory activity of (o-cresotinate) copper and zinc aquacomplexes]. / Protizápalová aktivita (o-krezotináto)mednatého a-zinocnatého akvakomplexu.

Using rat paw dextran-induced and carrageenan-induced edemas, the antiedematous activities of monohydrate of the diaquatetrakis(o-cresotato)dicopper(II) complex (CuoC) and the diaquabis(o-cresotato)zinc(II) complex (ZnoC) were assayed plethysmometrically. Dihydrate of the diaquabis(salicylato)copper(II) complex (CuS) and the diaquabis(salicylato)zinc(II) complex (ZnS) were used as the standards of comparison. All compounds were administered i.p. in a single dose of 50 mumol/kg body weight (calculated for the RCOO-fragment) 30 min before injecting the irritants. The antidextran/anticarrageenan activities of the species (expressed as a mean edema reduction) were found: CuoC 36/54%--ZnoC 59/65%--CuS 71/52%--ZnS 63/10%. The relationships between the coordination-chemical properties and the biological effects of the corresponding complexes are discussed.

[Anti-inflammatory activity of copper and zinc p-cresol dihydrate]. / Protizápalová aktivita dihydrátu p-krezotínanu mednatého a zinocnatého.

Using rat paw dextran-induced and carrageenan-induced edemas, the antiedematous activities of dihydrate of diaquatetrakis(p-cresotato)dicopper(II) complex (CupC) and diaquabis(p-cresotato)zinc(II) complex (ZnpC) were assayed plethysmometrically. Dihydrate of diaquabis(salicylato)copper(II) complex (CuS) and diaquabis(salicylato)zinc(II) complex (ZnS) were used as standards of comparison. All compounds were applied i.p. in a single dose of 50 mumol/kg body weight (calculated for the RCOO-fragment) 30 min before injecting the irritant. The antidextran/anticarrageenan activities of the species (expressed as a mean edema reduction) were found: CupC 46/74%--ZnpC 50/26%--CuS 71/52%--ZnS 63/10%. The relationships between the coordination-chemical properties and the biological effects of the corresponding complexes are discussed.

[Preparation and antiinflammatory activity of selected aqua-(aryloxyacetate) zinc complexes]. / Príprava a protizápalová aktivita vybraných akva-(aryloxyacetáto)zinocnatých komplexov.

Mononuclear aqua(aryloxyacetato)zinc(II) complexes of the composition [Zn(H2O)2(ROCH2COO)2] (R = phenyl, o-, m-, p-tolyl) were prepared as potential anti-inflammatory agents. The results of elemental analysis and parameters of IR spectra allow to classify the above-mentioned compounds to the group of carboxylatozinc(II) complexes with a distorted octahedral structure. They were assayed in rat paw carrageenan-induced edema and antiedematous effects were compared to those of free acids. Salicylic acid and its zinc(II) and copper(II) salts were used as the standards of comparison. All compounds were administered i.p. in a single dose of 50 mumol/kg body weight (calculated for the carboxylate fragment). In general, the zinc(II) complexes tested were clearly more effective (expressed as a mean edema reduction of 58-70-68-59%), including zinc(II) salicylate dihydrate (64%), than the uncomplexed acids (37-26-50-48%). Copper(II) salicylate tetrahydrate (60%) and salicylic acid (57%) exhibited comparable effects under the same conditions. The observed activities of the complexes are discussed in relation to their structures as well as to the coordination-chemical properties of the acidoligands under study.

[An unusual isolation of Neisseria meningitidis]. / Neobvyklá izolácia Neisseria meningitidis.

The authors describe a unique case of isolation of Neisseria meningitidis C:2a:P1.2,P1.5 in August 1997 from a 7-year-old female patient from a vaginal smear during purulent inflammation of the external genital following injury. This is the first described case of isolation of N. meningitidis from this site described in our country. The authors draw attention to the necessity to consider uncommon occurrences of N. meningitidis, and to examine atypical materials also under the microscope and to identify by biochemical methods all isolated Neisseriae incl. gonococci.

Long term follow-up study of laryngeal precancer.

The goal of this study was to determine subsequent malignancy on a discrete group of precancerous laryngeal lesions, and to assess the mortality. In a series of 227 patients, average age 51.8 years (ranging from 13 to 80 years). The changes were followed-up for 12.3 years (minimum of 5 years and maximum of 40 years). 58% are living without any sign of premalignant laryngeal mucosal disease, 13% with controlled precancer, and 3% in remission after surgery for carcinoma. 11% died (9% due to cause unrelated to the cancer) and 15% were lost for follow-up. 17% of the group with mucosal hyper- or metaplasia progressed to mild dysplasia, but none progressed to carcinoma. Reinke's oedema recurred in 4%, no malignancy was observed. Carcinoma developed in 16% of laryngeal papilloma (8% in situ and 8% invasive). 15% of mild dysplasia progressed in severity, but none transformed to malignancy. Moderate dysplasia progressed to severe dysplasia in 12%, carcinoma in situ in 4%. Of cases with severe dysplasia 13% developed in situ carcinoma while 43% progressed to invasive cancer. In the whole series progression to severe grade was seen in 7.1%, and malignant transformation in 4.4%. Three patients (1.3%) died due to subsequent carcinoma. Our results agree with some authors; but the majority of them reports higher incidence of malignant transformation. Invasive carcinoma was diagnosed in the follow-up in seven patients. Those represent only 3% of all laryngeal carcinomas diagnosed in our department in the same period of time. Based on the data we have evaluated the intensity of follow-up in patients with hyperplasia, metaplasia, keratosis and mild dysplasia.

[Anti-inflammatory activity of (cresoxyacetate)copper complexes]. / Protizápalová aktivita (krezoxyacetáto)mednatých komplexov.

In groups of mononuclear aqua(cresoxyacetato)copper(II) complexes of the composition [Cu(ROCH2COO)2(H2O)n] (R= 2- and 3-methylphenyl, n = 2; 4-methylphenyl, n = 3) and binu- clear phenazone(o-, m-, p-cresoxyacetato)copper(II) complexes of the composition [Cu2(ROCH2COO)4(phz)2] the anti-inflammatory activity was assayed in rat paw carrageenan-induced edema. The effects of the complexes were compared with each other and with those of the free acids. Salicylic acid and its cupric salt (tetrahydrate) were used as standards of comparison. All copounds were applied i.p. in a single dose of 50 mumol/kg body weight (calculated for the RCOO-fragment). In general, all Cu(II) complexes tested were clearly more effective (71-88%) than the corresponding free isomeric cresoxyacetic acids (47, 37, 45%), with the exception of diaquabis (o-cresoxyacetato)copper(II) complex (43%). Copper(II) salicylate tetrahydrate (57%) and salicylic acid (41%) were less active, too. The observed activities of complexes are discussed in relation to their structures.

[Antimicrobial activity of (N-salicylidene-DL-aspartate- and (N-salicylidene-L-asparaginate)-copper complexes with pyrazole-type ligands]. / Antimikróbna aktivita (N-salicylidén-DL-aspartáto)- a (N-salicylidén-L-asparagináto) mednatých komplexov s ligandmi pyrazolového typu.

By a reaction of salicylaldehyde (Scl) with the corresponding amino acids and by the next complexation reaction of the formed Schiff bases with Cu2+ ions in an aqueous-alcoholic medium, aqua (N-salicylideneaminoalkanoato)copper(II) complex chelates of the composition Cu(Scl-DL-Asp(2-)) (H2O)2, Ip and Cu(Scl-L-Asn(2-)(H2O), In were prepared. The monodiazole complexes with pyrazole IIp and IIn (as monohydrate) as well as with 3,5-dimethylpyrazole IIIp a IIIn were prepared by replacing the molecule of H2O in the parent aquacomplexes with the diazoles under the same reaction conditions. Using a routine dilution micromethod, the antimicrobial activity of the prepared complexes and free diazoles was tested against Staphylococcus aureus, Escherichia coli and Candida albicans. Only a significant antistaphylococcus activity was found (highest for the complex IIn; MIC = 39 micrograms/cm3). All chelates (Ip,n-IIIp,n) were more effective (MIC = 39-156 micrograms/cm3) than both pyrazole (312 micrograms/cm3)and 3,5-dimethylpyrazole (625 micrograms/cm3) alone. The relationship between the coordination-chemical properties and the biological effects of the complexes studied is discussed.

[Antiedematous activity of certain arylcarboxylate copper aquacomplexes]. / Antiedematózna aktivita vybraných arylkarboxylátomednatých akvakomplexov.

Using rat paw carrageenan edema, the anti-inflammatory activity of nine selected arylcarboxylatocopper(II) aquacomplexes of the general composition Cu(RCOO)2.nH2O, where R represents 2-hydroxy-Y-methylphenyl, Y = 3 (n = 1.5), 4 (4) or 5 (2); 2-hydroxy-3,6-dimethylphenyl (n = 4); 2,5-diacetoxyphenyl (1); 2-methoxy-(1) and 4-methoxyphenyl (3); 2-furyl (3) and 2-thienyl (1), was assayed and compared to that of the free acids. Copper(II) salicylate tetrahydrate and salicylic acid were used as standards for comparison. All compounds were applied i.p. in a single dose of 50 mumol/kg body weight, calculated for the RCOO-fragment. m-Cresotato- (mean edema reduction 70%) and p-cresotatocopper(II) (80%) aquacomplexes were clearly more effective than copper(II) salicylate tetrahydrate (55%). The nonsubstituted hydroxyl of the salicylate skeleton of acidoligands is required for the activity of the complexes and of free acids tested. Isomeric cresotic acids (82-47-62%) and 2-furoic acid (48%) exhibited a higher effect than salicylic acid (42%). The relationship between the coordination-chemical properties and the biological effects of the complexes studied is discussed.

[Antiedema activity of selected compounds with a gallate skeleton]. / Antiedematózna aktivita vybraných zlúcenín s galátovým skeletom.

Using rat paw dextran-induced and carrageenan-induced edemas, the anti-inflammatory activity of gallic acid (I), triacetylgallic acid (II) and monohydrate copper(II) triacetylgallate (III) was assayed. All compounds tested were applied i.p. in a single dose of 50 mumol/kg body weight, calculated for the RCOO-fragment. The average antiedematous activities in dextran/carrageenan edemas were decreasing in the following order: III (55.9/41.8%) > I (38.6/31.1%) > II (-3.4/13.3%). The relationship between the biological effects found and gallic acid as well as its structural derivatives is discussed.

[Anti-inflammatory activity of aqua-bis(2,Y-diacetoxybenzoate)-copper complexes (Y=4, 5 or 6)]. / Protizápalová aktivita akva-bis(2,Y-diacetoxybenzoáto)-mednatých komplexov (Y = 4, 5 alebo 6).

In a group of binuclear copper (II) complexes of the composition [Cu2(RCOO)4(H2O)2] (R = 2,4-diacetoxyphenyl (I), 2,5-diacetoxyphenyl (II) and 2,6-diacetoxyphenyl (III)), the anti-inflammatory activity was assayed in rat paw carrageenan-induced edema. Copper (II) salicylate tetrahydrate (IV) and salicylic acid were used as standards for comparison. All compounds were applied i.p. in a single dose of 50 mumol/kg body weight, calculated for the R-COO-fragment. The Cu(II) complexes tested were clearly more effective than the corresponding free diacetoxybenzoic acids, with an exception for the 2,5-diacetoxy derivative. The average anti-inflammatory activities of copper (II) complexes were decreasing in the following order: III (71.0%) = (70.6%) > IV (57.4%) > II (18.0%). Of the acids, only 2,6-diacetoxybenzoic acid (45.2%) was effective at the level of salicylic acid (44.9%). The relationship between the coordination-chemical properties and the biological effects of the complexes tested is discussed.

Mutagenicity of 4-nitroquinoline n-oxide after its complexation with copper (II) 2-chlorophenoxyacetate.

Using the AMes test with Salmonella typhimurium strains TA97, TA100 and TA102, it was found that the mutagenicity of 4-nitroquinoline-N-oxide was much lower than that of the tetrakis[mu-2-chlorophenoxyacetato(1-)-O,O[bis(4-nitro-quinoline- N-oxide-O)dicopper(II) complex.

[Antiexsudative activity of (methylsalicylate)copper-water compounds]. / Antiexsudacná aktivita (metylsalicyláto)mednatých akvakomplexov.

Using rat paw dextran edema, the antiexudative activity of the complexes of the composition Cu(RCOO)2.nH2O--R represents 2-hydroxy-Y-phenyl: Y = 3 (n = 1,5), Y = 4 (4), Y = 5 (2) or 2-hydroxy-3,6-dimethylphenyl (n = 4)--and of the corresponding uncomplexed acids was assayed. Salicylic and acetylsalicylic acids and their Cu(II) salts were used as standards of comparison. The compounds were administered i.p. in a single dose of 10 mg/kg body weight. In general, the acids were more effective than their copper(II) salts except for the pair m-cresotic acid--Cu(II) complex. Only p-cresotic acid (mean edema reduction 56%) and copper(II) m-cresotate tetrahydrate (43%) exhibited a biological activity comparable to those of salicylic acid (62%) and copper(II) salicylate tetrahydrate (70%). The observed activities of complexes are discussed in relation to their proposed structures.

Effects of Cu(II) complexes on photosynthesis in spinach chloroplasts. Aqua(aryloxyacetato)copper(II) complexes.

The inhibitory effect of 14 aqua(aryloxyacetato) copper(II) complexes on oxygen evolution rate in spinach chloroplasts has been investigated. The inhibitory effect of these effectors on photosynthesis was confirmed by Hill reaction as well as by EPR and fluorescence spectroscopies. The results of the EPR study showed that the sites of action of the studied effectors are Z+ and Y+ intermediates at the donor side of the photosystem (PS) 2. The EPR study also showed that another site of action is the oxygen evolving complex, namely its manganese cluster. The above suggestions were supported by the results of the fluorescence study as well. Based on the restoring of the photosynthetic electron transport to 2,6-dichlorophenol-indophenol in chloroplasts inhibited by the studied Cu(II) complexes using sym-diphenylcarbazide it can be assumed that the own core of PS2 (P680) and a part of the electron transport chain-at least up to plastoquinone-remain intact.

[Mutagenic activity of copper phenoxyacetate complexes]. / Mutagénna aktivita fenoxyacetátomednatých komplexov.

The mutagenic activity of phenoxyacetatocopper (II) complexes of the composition Cu(R-COO)2Ln-R = phenoxymethyl, L represents H2O (n = 3), phenazone (1), 4-nitropyridine N-oxide (1)--as well free phenoxyacetic acid and uncoordinated 4-nitropyridine N-oxide was tested against strains of Salmonella typhimurium (TA 100, TA 97 and TA 102) with or without metabolic activation. Using Ames methods in vitro, of the above-mentioned compounds only the 4-nitropyridine N-oxide complex in a concentration of 75 micrograms/dish, with 27.7% content of this neutral ligand) and this molecule ligand alone (in a concentration of 12.5 micrograms/dish) exhibited genotoxic effects. The relationship between the coordination-chemical properties and the biological effects of the compounds tested is discussed.