In the last few years, various studies have been providing evidence that metal ions are critically involved in the pathogenesis of major neurological diseases (Alzheimer, Parkinson). Metal ion ...chelators have been suggested as potential therapies for diseases involving metal ion imbalance. Neurodegeneration is an excellent target for exploiting the metal chelator approach to therapeutics. In contrast to the direct chelation approach in metal ion overload disorders, in neurodegeneration the goal seems to be a better and subtle modulation of metal ion homeostasis, aimed at restoring ionic balance. Thus, moderate chelators able to coordinate deleterious metals without disturbing metal homeostasis are needed. To date, several chelating agents have been investigated for their potential to treat neurodegeneration, and a series of 8-hydroxyquinoline analogues showed the greatest potential for the treatment of neurodegenerative diseases.
Najnovija istraživanja na polju neurodegeneracije jasno pokazuju da kovinski ioni imaju značajnu ulogu u patogenezi Alzheimerove kao i drugih neurodegenerativnih bolesti. U skladu s ovim spoznajama upotreba kovinskih kelatora predstavlja zanimljiv i inovativan farmakološki pristup daljnjem istraživanju i mogućoj terapiji neurodegenerativnih stanja. U ovom radu ukratko je dan sažetak istraživanja upotrebe kovinskih kelatora u tretmanu Alzheimerove bolesti s posebnim osvrtom na istraživanja analoga 8-hidroksikinolina.
In post-conflict states, environmental problems are often neglected regardless of their severity. According to UN data, Bosnia and Herzegovina (BiH) is one of the countries with the worst air ...pollution in the world, which has serious consequences for people's health and the economy. Given the importance of this issue, the paper investigates why it is not on the agenda of policymakers, by applying Kingdon's multiple streams model. The analysis leads to the conclusion that of the three streams (problem, policy, and politics), the politics stream remains the most problematic one. However, the author argues that Kingdon's original model is deficient in explaining why this problem is off the agenda, since it only includes domestic actors, while in the case of post-conflict BiH, as well as some other post-conflict countries, international actors play a significant role. In order to overcome this shortcoming, the model itself is enhanced by an insight into the role that international actors played in relation to this problem. It is concluded that the problems of environmental protection were largely ignored by international actors as well, primarily due to the nature of the liberal model of peacebuilding, that predominantly focused on building democratic institutions.
U postkonfliktnim državama problemi zaštite okoliša često se zanemaruju unatoč njihovoj važnosti. Prema podacima UN-a, Bosna i Hercegovina (BiH) jedna je od zemalja s najgorim zagađenjem zraka na svijetu, što ima ozbiljne posljedice na zdravlje ljudi i ekonomiju. Primjenjujući Kingdonov model višestrukih struja, rad istražuje zašto ovo pitanje nije na dnevnom redu kreatora javnih politika. Analiza upućuje na zaključak kako je od tri toka u modelu (tok problema, javnih politika i politike) tok politike najproblematičniji. Ipak, autorica zaključuje kako je izvorni Kingdonov model manjkav u objašnjenju zašto je ovaj problem izvan dnevnog reda, budući da u obzir uzima isključivo domaće aktere, dok u slučaju postkonfliktne BiH, kao i nekih drugih postkonfliktnih država, međunarodni akteri igraju značajnu ulogu. Kako bi se prevladao ovaj nedostatak, sam model nadograđuje se uvidom u ulogu koju su međunarodni akteri imali u vezi s ovim problemom. Zaključuje se kako su, zbog prirode liberalnog modela izgradnje mira u kojemu se fokus stavljao na izgradnju demokratskih institucija, problemi zaštite okoliša uvelike ignorirani i od strane međunarodnih aktera.
The in vitro antimicrobial activity of Fe(III) and Ga(III) complexes with
N
'-(2,3-dihydroxy-phenylmethylidene)-3-pyridinecarbohydrazide (
H
2
L
1
),
N
...'-(2,4-dihydroxy-phenyl-methylidene)-3-pyridinecarbohydrazide (
H
2
L
2
),
N
'-(2,5-dihydroxy-phenylmethylidene)-3-pyridinecarbohydrazide (
H
2
L
3
),
N
'-(2-hydroxy-3-methoxyphenyl-methylidene)-3-pyridine-carbohydrazide (
H
2
L
4
),
N
'-(2-hydroxy-4-methoxyphenylmethyl-idene)-3-pyridine-carbohydrazide (
H
2
L
5
), and
N
'-(2-hydroxy-5-methoxyphenylmethylidene)-3-pyridinecarbo-hydrazide (
H
2
L
6
) toward several Gram-positive strains of
Staphylococcus aureus
, a Gram-negative strain of
Escherichia coli
, and a yeast
Candida albicans
were investigated. Fe(III)-complexes do not possess antimicrobial activity against all tested strains at concentrations up to 10 mg mL
–1
. Ga(III) complexes with dihydroxy derivatives showed selective activity, while the broadest range of antibacterial and antifungal activities was observed for complex with 2-hydroxy-3-methoxy-derivative, ligand
H
2
L
5
. In addition, the coordination properties of ligands
H
2
L
1
–H
2
L
3
in solution were investigated by UV–Vis spectroscopy. The stability constants (log
K
) for Ga(III)-
H
2
L
1:1 complexes in MeOH/H
2
O 1/1 at pH 2.52 were determined, and amounted to 5.8, 5.68, and 4.7, respectively. Detailed characterization of complexes was performed by high-resolution mass spectrometry. The fragmentation pathways for dimer Fe
2
(
L
1
)
2
2+
, Fe(
HL
)
2
+
, Ga(
HL
2
)
2
+
and adduct ions are given. The comparison with analogue Ga(III) and Fe(III) complexes with compounds
H
2
L
4
–H
2
L
6
was made as well.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The presence of a microgap along an implant–abutment connection (IAC) is considered the main disadvantage of two-piece implant systems. Its existence may lead to mechanical and biological ...complications. Different IAC designs have been developed to minimise microleakage through the microgap and to increase the stability of prosthodontic abutments. Furthermore, different sealing materials have appeared on the market to seal the gap at the IAC. The purpose of this study was to evaluate the antimicrobial efficacy and permeability of different materials designed to seal the microgap, and their behaviour in conical and straight types of internal IACs. One hundred dental implants with original prosthodontic abutments were divided into two groups of fifty implants according to the type of IAC. Three different sealing materials (GapSeal, Flow.sil, and Oxysafe gel) were applied in the test subgroups. The contamination of implant–abutment assemblies was performed by a joint suspension containing Candida albicans and Staphylococcus aureus. It was concluded that the IAC type had no significant influence on microleakage regarding microbial infection. No significant difference was found between the various sealing agents. Only one sealing agent (GapSeal) was found to significantly prevent microleakage. A complete hermetic seal was not achieved with any of the sealing agents tested in this study.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The microenvironment of the oral cavity is altered when an implant, a biocompatible foreign body, is inserted into the mouth. Bacteria settle in the tissues in and around the implant due to the ...passage of microorganisms through the microgap at the connection of the implant and prosthetic abutment. To prevent colonization of the implant by microorganisms, one idea is to use sealing and antimicrobial materials to decontaminate the implant-abutment interface and close the microgap. The purpose of this study is to evaluate the antimicrobial efficacy and permeability of different types of sealing materials at the implant-abutment interface, under static conditions. Three different sealing material (GapSeal gel, Oxysafe gel and Flow.sil) were used for sealing the implant-abutment interfaces in 60 titanium dental implants, which were first contaminated with a solution containing
and
for 14 days under an aerobic condition. Results showed that a complete seal against bacterial infection was not formed at the implant-abutment interface, while for fungal infections, only GapSeal material helped to prevent microleakage. Findings of this in vitro study reported that application of sealing material before abutment connection may reduce peri-implant bacterial and fungal population compared with the interface without sealing material.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Implant-abutment connection (IAC) is a key factor for the long-term success and stability of implant-supported prosthodontic restoration and its surrounding tissues. Misfit between prosthodontic ...abutment and implant at the IAC leads to technical and biological complications. Two kinds of prosthodontic abutments are currently available on the market: original and third-party abutments. The aim of this pilot study was to test and compare the internal fit (gap) at the implant-abutment interface depending on the abutment fabrication method based on microbial leakage in static conditions and the need for the use of gap sealing material. Two groups of 40 implants were formed on the basis of the type of abutment. In each of the groups of two implant systems, two subgroups of 10 implants were formed. The tested subgroups consisted of 10 implants with sealing material and a negative control subgroups consisting of 10 implants without any sealing material. The test material, GapSeal (Hager and Werken, Duisburg, Germany) was applied in the test subgroups. The implant-abutment assemblies were contaminated with a solution containing
and
for 14 days under aerobic conditions. Results showed that there was no statistically significant difference regarding the microbial leakage between the original and third-party custom-made abutments, regardless of the use of sealing material. It can be concluded that the abutment fabrication method has no significant influence on sealing efficacy regarding the bacterial and fungal leakage in static conditions.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Polymicrobial biofilm removal and decontamination of the implant surface is the most important goal in the treatment of periimplantitis. The aim of this study is to evaluate the efficacy of four ...different decontamination methods for removing
and
biofilms in vitro. Seventy-five dental implants were contaminated with a bacterial suspension and randomly divided into five groups (
= 15): the negative control group, which received no treatment; the positive control group, treated with 0.2% chlorhexidine; group 1, treated with a chitosan brush (Labrida BioCleanTM, Labrida AS, Oslo, Norway); group 2, treated with a chitosan brush and 0.2% chlorhexidine; and group 3, treated with a device based on the electrolytic cleaning method (GalvoSurge, GalvoSurge Dental AG, Widnau, Switzerland). The colony-forming unit (CFU) count was used to assess the number of viable bacteria in each sample, and statistical analyses were performed. When compared to the negative control group, all the decontamination methods reduced the CFU count. The electrolytic cleaning method decontaminated the implant surface more effectively than the other three procedures, while the chitosan brush was the least effective. Further research in more realistic settings is required to assess the efficacy of the decontamination procedures described in this study.
Environmentally benign layer-by-layer (LbL) deposition was used to obtain flame-retardant and antimicrobial cotton. Cotton was coated with 8, 10, and 12 phytic acid (PA) and chitosan (CH)-urea ...bilayers (BL) and then immersed into copper (II) sulfate (CuSO4) solution. Our findings were that 12 BL of PA/CH-urea + Cu2+ were able to stop flame on cotton during vertical flammability testing (VFT) with a limiting oxygen index (LOI) value of 26%. Microscale combustion calorimeter (MCC) data showed a reduction of peak heat release rates (pHRR) of more than 61%, while the reduction of total heat release (THR) was more than 54%, relative to untreated cotton. TG-IR analysis of 12 BL-treated cotton showed the release of water, methane, carbon dioxide, carbon monoxide, and aldehydes, while by adding Cu2+ ions, the treated cotton produces a lower amount of methane. Treated cotton also showed no levoglucosan. The intumescent behavior of the treatment was indicated by the bubbled structure of the post-burn char. Antibacterial testing showed a 100% reduction of Klebsiella pneumoniae and Staphylococcus aureus. In this study, cotton was successfully functionalized with a multifunctional ecologically benign flame-retardant and antibacterial nanocoating, by means of LbL deposition.
The sensitivity of chitosan to environmental conditions and processing conditions can stress its structure and cause degradation of this polymer on various application carriers. The stability of ...chitosan in a designed textile structure of standard polyester fabric with chitosan was analysed in a multiple washing process with a standard detergent by studying the properties before and after 10 washing cycles. The chitosan was coated on standard and alkali treated polyester fabrics. Washing was performed with an ECE A reference detergent at 60 °C according to the Standard protocol HRN EN ISO 6330 in 10 cycles. The washing stability of chitosan onto polyester fabrics was monitored by a staining test, zeta potential, breaking force, breaking elongation, pilling propensity, touch, whiteness, moisture transport, antimicrobial activity and morphological features. The staining test confirmed the wash stability of chitosan coated on alkali hydrolised polyester fabrics, while the chitosan coated on standard polyester fabric disappeared. Zeta potential proved to be the significant parameter for determining chitosan` stability. The tensile properties of fabric samples were harmonised with other characterisation parameters. Coating of polyester fabric with chitosan increased the elasticity of all samples. The antimicrobial activity of polyester fabrics coated with chitosan against Staphylococcus aureus was reduced by 20% after 10 washing cycles. All the characterisation parameters proved that polyester fabric as a chitosan carrier should be surface modified for designing a stable bioactive textile structure of chitosan and polyester.
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