Photosensitizers based on porphyrin derivatives as a potential photodynamic agent

Photodynamic therapy (PDT) can be defined as the administration of photosensitizer either systemically, locally, or topically to a patient bearing a lesion (frequently but not always cancer), followed after some time by the illumination of the lesion with visible light (usually long wavelength red light). In the presence of molecular oxygen it leads to the generation of cytotoxic species and consequently to cell death and tissue destruction. The singlet oxygen have high reactivity and short half-life. Due to this, PDT directly affects only those biological substrates that are close to the region where these species are generated, usually within a 20 nanometers radius. Therefore, photosensitizers localization is a primary factor in drug release studies to target tissues because it selectivity promotes localized sensitization. In this study, the photosensitive compounds (G0, G1, G2) based on the rings porphyrin were synthesized and characterized (SEM, ATR-IR, NMR, thermal analysis). These molecules were also incorporated into chitosan films. The two step synthesis towards novel macrocycles were elaborated: alkylation reactions and macrocyclization reactions. The photostability of the obtained photosensitizers using high pressure mercury vapour lamp was examined. In the absorption spectra two characteristic bands for the obtained compound are observed: the Soret band located in the range of 300-400 nm and the Q band within 600-800 nm. The amount of produced singlet oxygen at ambient temperature in aerobic conditions was also determined. The lowest value of singlet oxygen quantum yield revealed G0 and the highest revealed G1. The aggregation study was also performed. This phenomenon is well-known especially for phthalocyanines and porphyrin derivatives. The results of the obtained compounds were compared with the results of the commercially available porphyrins. Bibliography: [1] D.P. Ferreiraa, D.S. Conceiçãoa, R.C. Calhelhac, T. Sousaa, Radu Socoteanub, I.C.F.R. Ferreirac, L.F. Vieira Ferreira, Carbohydrate Polymers 2016, 151, 160-171. [2] G.M. Fioramonti Calixto, J. Bernegossi, L. Marise de Freitas, C. R. Fontana, M. Chorilli, Molecules 2016, 21, 342-360. The project was supported by research grant: National Science Centre 2015/19/N/NZ7/0293

Nurses and Pharmacists in Interdisciplinary Team of Health Care Providers in Photodynamic Therapy

Background: The modern treatment is based on wide cooperation between diverse representatives of medical professions. The photodynamic therapy is a noninvasive method of treatment both neoplastic diseases and miscellaneous noncancerous illnesses. It is complementary and competitive in some way to various traditional treatment techniques, including chemotherapy, radiotherapy, and surgery. This review emphasizes the significance of collaboration between specialists engaged in research, development, and practical use of photodynamic therapy

S-seco-porphyrazine as a new member of the seco-porphyrazine family – Synthesis, characterization and photocytotoxicity against cancer cells

An important subgroup within the porphyrazine (Pz) family constitutes seco-porphyrazines, in the chemical structure of which one pyrrole unit is opened in the oxidative process. So far, there are only limited data on N-seco- and C-seco-Pzs. Here, the synthesis of a novel member of the Pzs seco-family, represented by an S-seco-tribenzoporphyrazine analogue, 22,23-bis(4-(3,5-dibutoxycarbonylphenoxy)butylsulfanyl)tribenzo[b,g,l]-22,23-dioxo-22,23-seco-porphyrazinato magnesium(II), is reported, with moderate 34% yield. The new derivative was characterized using NMR spectroscopy, UV–Vis spectroscopy, and mass spectrometry. In the photochemical study performed following the indirect chemical method with 1,3-diphenylisobenzofuran, S-seco-Pz revealed a high singlet oxygen quantum yield of 0.27 in DMF. Potential photocytotoxicity of S-seco-Pz was assessed in vitro on three cancer cell lines – two oral squamous cell carcinoma cell lines derived from the tongue (CAL 27, HSC-3) and human cervical epithelial adenocarcinoma cells (HeLa). In the biological study, the macrocycle was tested in its free form and after loading into liposomes. It is worth noting that S-seco-Pz was found to be non-toxic in the dark, with cell viability levels over 80%. The photocytotoxic IC50 values for free S-seco-Pz were 0.61, 0.18, and 4.1 µM for CAL 27, HSC-3 and HeLa cells, respectively. Four different liposomal compositions were analyzed, and the cationic liposomes revealed the highest photokilling efficacy, with the IC50 values for CAL 27, HSC-3, and HeLa cells at 0.24, 0.25, and 0.31 µM, respectively. The results of the photocytotoxicity study indicate that the new S-seco-tribenzoporphyrazine can be considered as a potential photosensitizer in photodynamic therapy of cancer, along with the developed cationic liposomal nanocarrier

Genetic portrait of polyamine transporters in barley: insights in the regulation of leaf senescence

Nitrogen (N) is one of the most expensive nutrients to supply, therefore, improving the efficiency of N use is essential to reduce the cost of commercial fertilization in plant production. Since cells cannot store reduced N as NH3 or NH4+, polyamines (PAs), the low molecular weight aliphatic nitrogenous bases, are important N storage compounds in plants. Manipulating polyamines may provide a method to increase nitrogen remobilization efficiency. Homeostasis of PAs is maintained by intricate multiple feedback mechanisms at the level of biosynthesis, catabolism, efflux, and uptake. The molecular characterization of the PA uptake transporter (PUT) in most crop plants remains largely unknown, and knowledge of polyamine exporters in plants is lacking. Bi-directional amino acid transporters (BATs) have been recently suggested as possible PAs exporters for Arabidopsis and rice, however, detailed characterization of these genes in crops is missing. This report describes the first systematic study to comprehensively analyze PA transporters in barley (Hordeum vulgare, Hv), specifically the PUT and BAT gene families. Here, seven PUTs (HvPUT1-7) and six BATs (HvBAT1-6) genes were identified as PA transporters in the barley genome and the detailed characterization of these HvPUT and HvBAT genes and proteins is provided. Homology modeling of all studied PA transporters provided 3D structures prediction of the proteins of interest with high accuracy. Moreover, molecular docking studies provided insights into the PA-binding pockets of HvPUTs and HvBATs facilitating improved understanding of the mechanisms and interactions involved in HvPUT/HvBAT-mediated transport of PAs. We also examined the physiochemical characteristics of PA transporters and discuss the function of PA transporters in barley development, and how they help barley respond to stress, with a particular emphasis on leaf senescence. Insights gained here could lead to improved barley production via modulation of polyamine homeostasis

Pro Libris: Lubuskie Pismo Literacko-Kulturalne, nr 3 (2009)

134 s. : il.

Modeling and Monitoring of Hydrodynamics and Surface Water Quality in the Sulejów Dam Reservoir, Poland

The aim of this work is to evaluate core variables of the ecological potential of the Sulejów Reservoir (temperature distribution, flow velocities, and concentrations of selected indicators, e.g., phosphates, nitrates, the abundance of phytoplankton) using a three-dimensional hydrodynamic model, GEMSS-HDM (generalized environmental modeling system for surface waters), coupled with a water quality model, WASP EUTRO (GEMSS-WQM). The monitoring data necessary to build the model were obtained from two multiparameter probes that were submerged in two locations in the Sulejów Reservoir. An ADCP current profiler was used to collect data for hydrodynamic model calibration and verification. Total error between computed and measured velocity was estimated at 10–15%. A high concentration of chlorophyll-a during the vegetation season of 2015 (0.02 mg/L) was coupled with high water temperature (above 25 °C) and low concentrations of biogenic compounds (phosphorus and nitrogen at 0.02 and 0.001 mg/L, respectively). In 2015, NO3-N was the limiting nutrient in the Sulejów Reservoir. Maximum growth of algae was observed in June and July 2015 (0.02 mg/L chla) along the entire length of the reservoir; algae bloom volume reduction was observed in September (0.004 mg/L chla). Proposed scenarios for nutrient reduction—50% reduction of phosphate-phosphorus (PO4-P) and nitrate-nitrogen (NO3-N) from agriculture areas as well as 50% reduction of discharges from septic tanks—led to a considerable reduction of nutrient concentrations in the reservoir waters; it additionally favors reducing the concentration of chlorophyll-a. The obtained results indicate that these sources of pollutants are mainly responsible for the poor water quality status of the reservoir and more intensive eutrophication phenomena.publishedVersio

Wentylacja naturalna a jakość powietrza wewnętrznego w budynkach mieszkalnych wielorodzinnych – wskazanie problemu, studium przypadku

Existing and designed residential buildings should provide the residents with appropriate indoor microclimatic conditions. Both in terms of thermal comfort and indoor air quality. Strong tendencies towards saving energy in buildings contribute to the use of materials with better thermal insulation (walls) and airtightness coefficients (doors and windows). In the last few years there has been a tendency towards air-tight sealing of buildings. This phenomenon can be seen both in older buildings being refurbished as well as in those that are new or thermally-upgraded. At the same time, in existing and new buildings traditional, gravity ventilation is used, and is becoming an extremely important factor in achieving the required indoor conditions. The following are some of the results of the research on this subject, which will, hopefully, provide new insight. The paper describes the use of new technologies, such as hybrid ventilation, in existing buildings. The results presented herein have been achieved from comprehensive measurements in the buildings with natural and hybrid ventilation. The aim of the paper is to present and summarize preliminary studies describing the influence of natural and hybrid ventilation as well as airtightness on an indoor environment.Istniejące i projektowane budynki mieszkalne powinny zapewniać mieszkańcom odpowiednie warunki mikroklimatu wewnętrznego zarówno pod względem komfortu cieplnego, jak i jakości powietrza w pomieszczeniach. Silne tendencje do oszczędzania energii w budynkach przyczyniają się do stosowania materiałów o lepszej izolacyjności termicznej (ściany) i szczelności (drzwi i okna). W ciągu ostatnich kilku lat pojawiła się tendencja do hermetycznego uszczelniania budynków. Zjawisko to można zaobserwować zarówno w starych remontowanych budynkach, jak i nowych lub termomodernizowanych. Jednocześnie, w budynkach nowych oraz istniejących stosowane są tradycyjne rozwiązania wentylacji grawitacyjnej. W takich przypadkach działanie wentylacji staje się istotnym czynnikiem do realizacji wymagań jakości powietrza w pomieszczeniach. Przedstawiono wybrane wyniki badań dotyczących tej problematyki, ujmujące temat w nowym świetle, z możliwością wykorzystania nowych technologii, takich jak wentylacja hybrydowa, w istniejących budynkach. Uzyskano je drogą kompleksowych pomiarów w istniejących budynkach mieszkalnych. Celem opracowania jest zaprezentowanie i podsumowanie wstępnych badań opisujących wpływ wentylacji naturalnej i hybrydowej oraz szczelności przegród na stan środowiska wewnętrznego

Modeling and Monitoring of Hydrodynamics and Surface Water Quality in the Sulejów Dam Reservoir, Poland

The aim of this work is to evaluate core variables of the ecological potential of the Sulejów Reservoir (temperature distribution, flow velocities, and concentrations of selected indicators, e.g., phosphates, nitrates, the abundance of phytoplankton) using a three-dimensional hydrodynamic model, GEMSS-HDM (generalized environmental modeling system for surface waters), coupled with a water quality model, WASP EUTRO (GEMSS-WQM). The monitoring data necessary to build the model were obtained from two multiparameter probes that were submerged in two locations in the Sulejów Reservoir. An ADCP current profiler was used to collect data for hydrodynamic model calibration and verification. Total error between computed and measured velocity was estimated at 10–15%. A high concentration of chlorophyll-a during the vegetation season of 2015 (0.02 mg/L) was coupled with high water temperature (above 25 °C) and low concentrations of biogenic compounds (phosphorus and nitrogen at 0.02 and 0.001 mg/L, respectively). In 2015, NO3-N was the limiting nutrient in the Sulejów Reservoir. Maximum growth of algae was observed in June and July 2015 (0.02 mg/L chla) along the entire length of the reservoir; algae bloom volume reduction was observed in September (0.004 mg/L chla). Proposed scenarios for nutrient reduction—50% reduction of phosphate-phosphorus (PO4-P) and nitrate-nitrogen (NO3-N) from agriculture areas as well as 50% reduction of discharges from septic tanks—led to a considerable reduction of nutrient concentrations in the reservoir waters; it additionally favors reducing the concentration of chlorophyll-a. The obtained results indicate that these sources of pollutants are mainly responsible for the poor water quality status of the reservoir and more intensive eutrophication phenomena

Center or periphery? Modeling the effects of focal adhesion placement during cell spreading.

Focal adhesions are often observed at the cell's periphery. We provide an explanation for this observation using a system-level mathematical model of a cell interacting with a two-dimensional substrate. The model describes the biological cell as a hypoelastic continuum material whose behavior is coupled to a deformable, linear elastic substrate via focal adhesions that are represented by collections of linear elastic attachments between the cell and the substrate. The evolution of the focal adhesions is coupled to local intracellular stresses which arise from mechanical cell-substrate interactions. Using this model we show that the cell has at least three mechanisms through which it can control its intracellular stresses: focal adhesion position, size, and attachment strength. We also propose that one reason why focal adhesions are typically located on the cell periphery instead of its center is because peripheral focal adhesions allow the cell to be more sensitive to changes in the microenvironment. This increased sensitivity is caused by the fact that peripherally located focal adhesions allow the cells to modulate its intracellular properties over a much larger portion of the cell area