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Degradation of sodium alkylbenzenesulfonate (ABS) in the Fenton reagent in the presence of Cl- ions has been studied. An anionic surfactant sodium alkylbenzenesulfonate (C11-C14) has been selected as a model compound. The effect of individual components of the reactive system (H2 O2 , H2 O2 /Cl- , Fe2+/H2 O2 , Fe2+/H2 O2 /Cl- ) on the degree of ABS degradation has been determined. The degree of ABS degradation has been found to be affected by the presence of Cl- ions and the mutual molar ratios of individual components of the system studied. Moreover, it influences on the composition of the post-reaction mixture. The use of the Fenton reagent in the presence of Cl- ions resulted in the formation of chloroorganic compounds in the solution studied. 2,4,6-trichlorophenol was identified in reaction products and its presence was confirmed using the HPLC - MS method and by HPLC with an internal standard. No chloroproducts were identified during degradation of ABS by the system H2 O2 /Cl- . When only H2 O2 was applied, the concentration of the surfactant was unchanged.
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Ion transport in rabbit caecum at 12 and 36 months of age

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The aim of this study was to investigate the effect of aging on sodium and chloride ions transport in the isolated rabbit coecum. The experiment consisted in measuring PD- transepithelial electrical potential difference mV SM-mechanical stimulation and mechano-sensitivity (dPD) in collected from 12- and 36-month-old rabbits. A modified Ussing system was used for the experiment. Under the incubation in Ringer solution the values of PD and dPD of young rabbit caecum were, respectively, -3.0 ±0.4 mV and -1.2 ±0.3 mV. In 36-month rabbits, on the other hand, the values of these parameters were lower, PD by about 90% whereas dPD by about 83%. Incubation of young rabbits caecum with the presence of amiloride resulted in a reduction of PD by about 17 % and dPD by about 50%, while it did not influence the electrophysiological parameters of caecum in 36-month rabbits. Incubation with bumetanide on young rabbits caecum resulted in PD dropped by about 70% and dPD by about 83%. In the same incubation conditions as those applied for incubation of 36-month rabbits caecum, the level of PD decreased by about 67% while dPD by about 50%. Incubation of young rabbits caecum at the presence of both transport inhibitors resulted in PD decreased by about 87% and dPD by about 83%, whereas that applied for the old rabbits' caecum reduced PD by about 90%, without influencing dPD. Presented data demonstrate that the process of organism ageing inhibits sodium ion transport as well as reduces caecum epithelium sensitivity to mechanical stimuli. Probably, it is a consequence of a reduced with age release of neurotransmitter from sensory terminals; these neurotransmitters modify transepithelial ion transport.
One of the most critical sources of pollutants are road run-offs. Road run-off is a complex mixture of toxicants e.g. heavy metals, de-icing agents, organic compounds and water suspensions of solid substances. One of the most negative impact on the environment has sodium chloride which is used as de-icing agent. In the case of incorrect environment protection in the vicinity of roads pollutants may migrate to groundwater causing hazard to sources of potable water. One of the methods to prevent the migration of pollutants to groundwater is imposing the flow of polluted water through a reactive material filling a permeable reactive barrier (PRB). This paper examines the feasibility of selected reactive materials for the reduction chlorides concentration in road run-offs. Four different reactive materials: zero valent-iron, activated carbon, zeolite and geza rock have been chosen for studies. The tests results indicated that the most popular reactive materials used in PRB technology, activated carbon and zero-valent iron, removed exhibited the highest efficiency in chloride ions removal. Moreover, the composition of road run-off in samples collected along roads in Warsaw was determinated.
Channels selective for potassium or chloride ions are present in inner mitochondrial membranes. They probably play an important role in mitochondrial events such as the formation of pH and regulation of mitochondrial volume changes. Mitochondrial potassium and chloride channels could also be the targets for pharmacologically active compounds such as potassium channel openers and antidiabetic sulfonylureas. This review describes the properties, pharmacology, and current observations concerning the functional role of mitochondrial potassium and chloride channels.
Ion channels selective for chloride ions are present in all biological membranes, where they regulate the cell volume or membrane potential. Various chloride channels from mitochondrial membranes have been described in recent years. The aim of our study was to characterize the effect of stilbene derivatives on single-chloride channel activity in the inner mitochondrial membrane. The measurements were performed after the reconstitution into a planar lipid bilayer of the inner mitochondrial membranes from rat skeletal muscle (SMM), rat brain (BM) and heart (HM) mitochondria. After incorporation in a symmetric 450/450 mM KCl solution (cis/trans), the chloride channels were recorded with a mean conductance of 155 ± 5 pS (rat skeletal muscle) and 120 ± 16 pS (rat brain). The conductances of the chloride channels from the rat heart mitochondria in 250/50 mM KCl (cis/trans) gradient solutions were within the 70–130 pS range. The chloride channels were inhibited by these two stilbene derivatives: 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) and 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonic acid (SITS). The skeletal muscle mitochondrial chloride channel was blocked after the addition of 1 mM DIDS or SITS, whereas the brain mitochondrial channel was blocked by 300 μM DIDS or SITS. The chloride channel from the rat heart mitochondria was inhibited by 50–100 μM DIDS. The inhibitory effect of DIDS was irreversible. Our results confirm the presence of chloride channels sensitive to stilbene derivatives in the inner mitochondrial membrane from rat skeletal muscle, brain and heart cells.
Badania nad wpływem wybranych parametrów jakości środowiska wodnego (odczynu, ilość tlenu i jonów chlorkowych) na perifiton zasiedlający trzcinę prowadzono w czterech sezonach 2007 roku w kanałach melioracyjnych Lasku Południowego w Słupsku zarówno stale obfitych w wodę, jak i wysychających. W czasie badań wody w kanałach melioracyjnych charakteryzowały się znaczną zmiennością warunków tlenowych, natomiast porównywalnym odczynem i zasoleniem. Obserwowano natomiast znaczne różnice analizowanych parametrów w poszczególnych punktach. Gorsze warunki tlenowe, a częściowo również większe zasolenie i pH (st. 5) panowały w wysychających kanałach, niż w stale napełnionym wodą kanale głównym. Obserwowano równocześnie mniejsze natlenienie, zasolenie i pH na stanowisku zlokalizowanym przed kolektorem ściekowym niż za nim. W czasie analiz stwierdzono występowanie bogatego jakościowo zespołu organizmów poroślowych, składającego się z 19 taksonów (3 roślin i 16 zwierząt). Glony perifitonowe zdominowane zostały przez okrzemki (87%), którym towarzyszyły sinice (12%) oraz zielenice (< 1%), natomiast wśród mikrofauny poroślowej przeważały Peritricha (47,5%) a w makrofaunie Asellus aquaticus (22,4%). W celu uchwycenia wpływu wybranych parametrów fizyczno-chemicznych wód na skład jakościowy i ilościowy organizmów poroślowych zastosowano metody korelacji nieparametrycznej oraz ordynacyjne (PCA, CCA, DCA, RDA). Projekcja taksonów wskazała, że sedymentatory (Rotatoria) rozwijają się intensywniej w warunkach lepszego natlenienia i przy wyższym pH. Na stanowiskach oddalonych od zrzutu wód deszczowych obserwowano większe zagęszczeniem Testacea, Nauplius i Harpacticoida. Wyższa temperatura sprzyja wzrostowi zagęszczenia Testacea, Cyanophyta i Ciliata libera.
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