Potentiometric determination of cysteine with thiol sensitive silver-mercury electrode

A potentiometric procedure for cysteine thiol group concentration monitoring in media generating free radicals was developed using a thiol specific silver-mercury electrode. Electrolytic deposition of mercury on a silver wire and treatment with 20 mM cysteine in 0.5 M NaOH were used to produce the electrode. A silver-chloride electrode in saturated KCl was the reference. A glass capillary with 1 M KNO3 in 1% agarose gel was the liquid junction. The electrode responded to cysteine concentration in the range from 0.01 to 20 mM yielding a perfect linear relationship for the dependence of log [cysteine] versus electrode potential [mV], with b0 (constant) = -373.43 [mV], b1 (slope) = -53.82 and correlation coefficient r2 = 0.97. The electrode potential change per decade of cysteine concentration was 57 mV. The minimal measurable signal response was at a cysteine concentration of 0.01 mM. The signal CV amounted to 4-6% for cysteine concentrations of 0.01 to 0.05 mM and to less than 1% for cysteine concentrations of 0.5 to 20 mM. The response time ranged from about 100 s for cysteine concentrations of 0.01 to 0.1 mM to 30 s at higher cysteine concentrations. The standard curve reproducibility was the best at cysteine concentrations from 0.1 to 20 mM. In a reaction medium containing cysteine and copper(II)-histidine complex ([His-Cu]2+) solution in 55 mM phosphate buffer pH 7.4 the electrode adequately responded to changes in cysteine concentration. Beside cysteine, the silver-mercury electrode responded also to thiol groups of homocysteine and glutathione, however, the Nernst equation slope was about half of that for cysteine

Dynamics of reactive oxygen species generation in the presence of copper(II)-histidine complex and cysteine

Histidine-copper(II) complex (Cu-His2) is a form of bound copper necessary for cellular copper uptake. Due to the high affinity of histidine to copper(II) ions, the binding of copper(II) by histidine is considered a substantial part of plasma antioxidative defense. Also cysteine plays a role in the antioxidative system. However, we show here that in the presence of oxygen the histidine-copper(II) complex plus cysteine produces reactive oxygen species (ROS). Cysteine concentration was assayed using a thiol specific silver-mercury electrode. Hydrogen peroxide was assayed amperometrically using platinum electrode. ROS formation was followed by chemiluminescence of luminol-fluoresceine-enhanced system. Addition of cysteine to Cu-His2 solution at pH 7.4 in the presence of atmospheric oxygen initiates the synthesis of H2O2 and generation of ROS, which manifests as a burst of chemiluminescence. The reaction has two stages; in the first stage, cysteine is utilized for the synthesis of an unstable intermediary product which becomes a substrate for ROS formation. Anaerobic conditions inhibit ROS formation. Increased cysteine concentration enhances the lag phase of the oxidative burst without influencing the amount of ROS. The synthesis of ROS (measured by chemiluminescence) is proportional to the concentration of Cu-His2 employed. ROS production can be repetitively initiated by further additions of cysteine to the reaction medium. The study suggests that Cu-His2 catalyzes cysteine-dependent reduction of oxygen to superoxide employing an intermediary cysteine-copper(I) complex and enabling Fenton reaction with copper and hydrogen peroxide produced as a secondary product. In effect, Cu-His2 with cysteine may be a source of ROS in biological media

Effect of S-Allyl -L-Cysteine on MCF-7 cell Line 3-mercaptopyruvate sulfurtransferase/sulfane sulfur system, viability and apoptosis

The S-Allyl-L-cysteine (SAC) component of aged garlic extract (AGE) is proven to have anticancer, antihepatotoxic, neuroprotective and neurotrophic properties. -Cystathionase (CTH), cystathionine -synthase (CBS) and 3-mercaptopyruvate sulfurtransferase (MPST) are involved in H2S/sulfane sulfur endogenous formation from L-cysteine. The aim of the study was to determine the e ect of SAC on MCF-7 cells survival and apoptosis, which is a widely known approach to reduce the number of cancer cells. An additional goal of this paper was to investigate the e ect of SAC on the activity and expression of enzymes involved in H2S production. The experiments were carried out in the human breast adenocarcinoma cell line MCF-7. Changes in the cell viability were determined by MTT assay. Cell survival was determined by flow cytometry (FC). Changes in enzymes expression were analyzed using Western blot. After 24 h and 48 h incubation with 2245 M SAC, induction of late apoptosis was observed. A decrease in cell viability was observed with increasing SAC concentration and incubation time. SAC had no significant cytotoxic e ect on the MCF-7 cells upon all analyzed concentrations. CTH, MPST and CBS expression were confirmed in non-treated MCF-7 cells. Significant decrease in MPST activity at 2245 M SAC after 24 h and 48 h incubation vs. 1000 M SAC was associated with decrease in sulfane sulfur levels. The presented results show promising SAC e ects regarding the deterioration of the MCF-7 cells’ condition in reducing their viability through the downregulation of MPST expression and sulfate sulfur level reduction

The role of social trust in reward crowdfunding campaigns’ design and success

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Masywne przerzuty do skóry jako pierwszy objaw raka piersi — opis przypadku

Introduction: Metastases to the skin are relatively rare, but they are an important diagnostic and therapeutic challenge. In women skin metastases are the most commonly associated with breast cancer. In the men they are often associated with lung cancer. Skin metastasis most often are in form of blue-purple nodules and tumours with tendency of necrosis. Aim: The aim of this paper is to present the case of a patient with diagnosed breast cancer with skin involvement. Case report: The 48-years old female patient was admitted to The Department of Dermatology for diagnosis and treatment of dermal lesions in form of numerous blue-purple nodules and ulcerations localised on the skin of the chest. The ultrasound examination suggested a primary malignant lesion in the left breast spreading to the right side and numerous satellite nodules. A whole nodule was collected for histopathological and immunohistochemical examinations in order to make the final diagnosis. Histopathology tests confirmed the diagnosis of tumour metastases of the skin and positive immunohistochemical reactions for cytokeratin 7 (CK7) and for oestrogen receptors (ER) pointed mammary glands as the primary site. The patient was urgently referred to the Oncology Centre. Conclusions: The occurrence of skin metastasis in all tumour processes significantly worsens the prognosis of the patient. These changes should be quickly recognized by the oncologist or dermatologist. Sometimes the localization of primary tumour is not possible to determine without taking the biopsy for histopathological and immunohistochemistry assays. Rapid treatment of appropriate chemotherapy or radiotherapy can prolong life and reduce pain.Wstęp: Przerzuty nowotworów do skóry stanowią istotny problem diagnostyczy i terapeutyczny, chociaż występują stosunkowo rzadko. Przerzuty do skóry obserwowane są najczęściej w przebiegu raka sutka u kobiet i raka płuca w przypadku mężczyzn. Zazwyczaj mają one postać sinofioletowych guzków i guzów, niekiedy z tendencją do rozpadu. Cel pracy: Celem pracy jest przedstawienie przypadku pacjentki z rozpoznanym nowotworem piersi przebiegającym z zajęciem skóry. Opis przypadku: 48-letnia pacjentka została przyjęta do Kliniki Dermatologii w celu diagnostyki i leczenia zmian skórnych o charakterze licznych sinofioletowych guzków z tendencją do rozpadu oraz owrzodzeń zlokalizowanych na skórze gładkiej klatki piersiowej. W badaniu USG piersi całość obrazu przemawiała za procesem nowotworowym pierwotnie wywodzącym się z piersi lewej, z progresją zmian na stronę prawą, z licznymi guzkami satelitarnymi. Pobrano w całości guzek do badania histopatologicznego oraz immunohistochemicznego w celu ustalenia rozpoznania ostatecznego. Wynik badania histopatologicznego potwierdził rozpoznanie przerzutów nowotworowych do skóry, dodatnie odczyny immunohistochemiczne dla cytokeratyny 7 (CK 7) i receptorów estrogenowych (ER) wskazywały na sutek jako miejsce guza pierwotnego. Pacjentka została w trybie pilnym skierowana do Centrum Onkologii. Wnioski: Wystąpienie przerzutów do skóry w przypadku wszystkich procesów nowotworowych znacznie pogarsza rokowanie pacjenta. Zmiany te powinny być szybko rozpoznane przez prowadzącego onkologa lub dermatologa. Czasem punkt wyjścia nowotworu nie jest możliwy do ustalenia bez pobrania materiału do badania histopatologicznego i immunohistochemicznego. Szybkie wdrożenie odpowiedniej chemioterapii lub radioterapii pozwala przedłużyć życie chorych oraz zmniejszyć dolegliwości bólowe.

The investigation of internal pressure development in convective drying of shrinking and non-shrinking materials using green and fired clay as an example

[EN] The aim of present research was to measure and analyze the dynamic changes of internal pressure in shrinking vs. non-shrinking materials during convective drying for the use as a possible process control method. Drying experiments were carried out on wet and fired clay at 50°C and 60°C. In addition, the shrinkage curve was investigated. Experimental measurements show the existence of 4 stages of the process. The comparison of the results for wet and fired clay shows differences in pressure trends. During drying the internal pressure changes from underpressure to overpressure at the level of 3÷5kPa, what correlates well with transition from the first to the second drying period.Adamska, A.; Pakowski, Z.; Adamski, R. (2018). The investigation of internal pressure development in convective drying of shrinking and non-shrinking materials using green and fired clay as an example. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 115-122. https://doi.org/10.4995/IDS2018.2018.7470OCS11512

Development of forests in the former heathland landscape: changes in the habitat quality, structure of undergrowth, syntaxonomy of phytocoenoses and modern pollen deposition

This study presents changes in the quality of habitats between 1926 and 2013 in permanent units of forest division restored in the 19th century as a result of afforestation carried out in the landscape dominated by heaths and xerothermic grasslands. The research was conducted in the Zaborski Landscape Park, located in the north-western part of the Tuchola Forest − one of the largest forest complexes in Poland. Changes in the habitat quality were determined based on data included in seven consecutive inventory books. Assessment according to the 5-point quality scale was performed on the basis of average height reached by a pine forest stand of a certain age occurring in particular forest subsections. It has been found that the quality of habitat increased over 87 years by two classes, on average from IV to II. The number of species, especially deciduous trees and shrubs listed in inventory books, was an additional parameter expressing the habitat quality. The extent of habitat changes was also determined based on the types of syntaxa, which are represented by relevés forming the time series and made more or less at the same sites by different authors in 1961, 2002 and 2013, i.e. over the period of 52 years. Temporal changes in the structure of phytocoenoses and their syntaxonomic affiliation were determined using the classification and ordination methods. It has been found that in the study area and within the studied time horizon, there was a recession of dry coniferous forest which developed towards mesic (fresh) pine forests. Whereas within the fresh coniferous forest, there were transitions from the poor cladonietosum variant to the mesotrophic typicum variant, or from the typicum variant towards the fertile variant with a large contribution of Fagus sylvatica in the main tree layer and undergrowth. A change in the forest type from a pine monoculture to mixed pine-beech forest was also reflected in the spectrum of modern pollen deposition collected after annual exposures of Tauber traps. In this case, the observations were performed by the same research team over 15 years

Genetic variants in transforming growth factor-β gene (TGFB1) affect susceptibility to schizophrenia

Immense body of evidence indicates that dysfunction of immune system is implicated in the etiology of schizophrenia. The immune theory of schizophrenia is supported by alterations in cytokine profile in the brain and peripheral blood. Given the strong genetic background of schizophrenia, it might be assumed that aberrant production of cytokines might be the consequence of genetic factors. This study aimed at investigating the association between schizophrenia susceptibility and selected functional polymorphisms in genes encoding cytokines including: interleukin-2 (IL2 −330T>G, rs2069756), interleukin-6 (IL-6 −174G>C, rs1800795), interferon-γ (IFNG +874T>A, rs2430561) as well as for the first time transforming growth factor-β1 (TGFB1 +869T>C, rs1800470 and +916G>C, rs1800471). We recruited 151 subjects with schizophrenia and 279 controls. There was a significant difference in the genotype distribution and allelic frequency of the TGFB1 +869T>C between patients with schizophrenia and healthy controls (p < 0.05). The risk of schizophrenia was more than two-fold higher in carriers of T allele (CT+TT genotypes) than individuals with CC genotype. Given documented gender differences in incidence of schizophrenia, we conducted separate analyses of male and female participants. We have shown that the association was significant in females, while in males it reached a trend toward statistical significance. To the best of our knowledge, it is the first report showing the association between TGFB1 +869T>C polymorphism and schizophrenia