Presence Of Porphyrins Research Articles

Morphological and molecular changes in the Harderian gland of streptozotocin-induced diabetic rats.

Using a rat model of type 1 diabetes (T1D) obtained by treatment with streptozotocin, an antibiotic that destroys pancreatic β-cells, we evaluated the influence of subsequent hyperglycemia on the morphology and physiology of the Harderian gland (HG). HG is located in the medial corner of the orbit of many terrestrial vertebrates and, in rodents, is characterized by the presence of porphyrins, which being involved in the phototransduction, through photo-oxidation, produce reactive oxygen species activating the autophagy pathway. The study focused on the expression of some morphological markers involved in cell junction formation (occludin, connexin-43, and α-tubulin) and mast cell number (MCN), as well as autophagic and apoptotic pathways. The expression of enzymes involved in steroidogenesis [steroidogenic acute regulatory protein (StAR), and 3β-hydroxysteroid dehydrogenase (3β-HSD)] and the level of lipid peroxidation by thiobarbituric acid reactive species assay were also evaluated. The results strongly indicate, for the first time, that T1D has a negative impact on the pathophysiology of rat HG, as evidenced by increased oxidative stress, morphological and biochemical alterations, hyperproduction and secretion of porphyrins, increased MCN, reduced protein levels of StAR and 3β-HSD, and, finally, induced autophagy and apoptosis. All the combined data support the use of the rat HG as a suitable experimental model to elucidate the molecular damage/survival pathways elicited by stress conditions.

Photochemical Properties of Propargylamine-based Polymers

Propargylamines are a promising but quite poorly studied category of organic compounds. This work aimed to study the photochemical properties of propargylamines polymers containing porphyrin fragments with electron transfer reactions. The study was carried out in 2019 at the Institute of Organic Chemistry (RAS, Moscow, Russia). The obtained polymer was irradiated with a luminous source. The absorption spectra were studied by electron paramagnetic resonance using a radio spectrometer. The presence of porphyrin and propargylamine in the polymer solution has been established to promote the reaction of complexation. This is due to the presence of double bonds in the amino groups, whereas also porphyrin and bromanil, which is an electron acceptor. The resulting data allow explaining the processes involved in photochemical reactions during the irradiation of the porphyrin complex in the presence of bromanil. In the long-wavelength part of the spectrum (above 540 nm), electron phototransfer inside the polymer molecule to the porphyrin side and between molecules from the porphyrin anion radical to the neutral polymer molecule take place.

A Case of Recurrent Acute Abdomen in a Young Lady Masquerading as Somatoform Disorder

Acute intermittent porphyria (AIP) is a rare autosomal dominant hereditary metabolic disorder having protean manifestations. It usually presents with short duration of gastrointestinal symptoms followed by rapidly progressivefulminant neurological syndrome. It is a neurological emergency and mimics many other psychiatric and medical disorders and can be fatal if it remains undiagnosed and untreated. Further, specifictreatment in the form of Heme arginate is not universally available and very costly, so high clinical suspicion and early diagnosis and management of acute attack and prevention of further attacks are very important. Here, we report a 23 years old married female nurse presenting with recurrent acute abdomen requiring frequent hospital admissions along with convulsion during her last attack. The presence of porphyrins in urine confirms the diagnosis of AIP.

A Case of Recurrent Acute Abdomen in a Young Lady Masquerading as Somatoform Disorder

Acute intermittent porphyria (AIP) is a rare autosomal dominant hereditary metabolic disorder having protean manifestations. It usually presents with short duration of gastrointestinal symptoms followed by rapidly progressive fulminant neurological syndrome. It is a neurological emergency and mimics many other psychiatric and medical disorders and can be fatal if it remains undiagnosed and untreated. Further, specific treatment in the form of Heme arginate is not universally available and very costly, so high clinical suspicion and early diagnosis and management of acute attack and prevention of further attacks are very important. Here, we report a 23 years old married female nurse presenting with recurrent acute abdomen requiring frequent hospital admissions along with convulsion during her last attack. The presence of porphyrins in urine confirms the diagnosis of AIP.

A Commonly Missed Well Known Entity- Acute Intermittent Porphyria: A Case Report

Acute intermittent porphyria (AIP) is a rare autosomal dominant hereditary metabolic disorder having protean manifestations. It usually presents with short duration of gastrointestinal symptoms followed by rapidly progressive fulminant neurological syndrome. It is a neurological emergency and mimics many other psychiatric and medical disorders and can be fatal if it remains undiagnosed and untreated. Further, specific treatment in the form of Heme arginate is not universally available and very costly, so high clinical suspicion and early diagnosis and management of acute attack and prevention of further attacks are very important. Here, we report a 23 years old married female nurse presenting with recurrent acute abdomen requiring frequent hospital admissions along with convulsion during her last attack. The presence of porphyrins in urine confirms the diagnosis of AIP.

A Young Lady with Recurrent Acute Abdomen

Acute intermittent porphyria (AIP) is a rare autosomal dominant hereditary metabolic disorder having protean manifestations. It usually presents with short duration of gastrointestinal symptoms followed by rapidly progressive fulminant neurological syndrome. It is a neurological emergency and mimics many other psychiatric and medical disorders and can be fatal if it remains undiagnosed and untreated. Further, specific treatment in the form of Heme arginate is not universally available and very costly, so high clinical suspicion and early diagnosis and management of acute attack and prevention of further attacks are very important. Here, we report a 23 years old married female nurse presenting with recurrent acute abdomen requiring frequent hospital admissions along with convulsion during her last attack. The presence of porphyrins in urine confirms the diagnosis of AIP.

The importance of porphyrins in blue light suppression of Streptococcus agalactiae

It is well documented that blue light absorption by bacterial chromophores triggers downstream production of reactive oxygen species (ROS), which in turn results in bacterial cell death. To elucidate the importance of chromophores in the bactericidal effect of blue light, and to determine whether blue light absorption per se or the presence of porphyrins known to engender ROS is crucial in blue light treatment, we studied the effect of 450 nm pulsed light on Streptococcus agalactiae, also known as Group B Streptococcus (GBS) strain COH1. GBS does not synthesize porphyrins but has a blue light-absorbing chromophore, granadaene. We irradiated planktonic cultures of GBS with or without exogenous chromophore supplementation using either protoporphyrin IX (PPIX), coproporphyrin III (CPIII), Nicotinamide adenine dinucleotide (NAD), reduced nicotinamide adenine dinucleotide (NADH), Flavin adenine dinucleotide (FAD), or Flavin mononucleotide (FMN). Quantification of surviving bacterial colonies, presented as percent survival and CFU/mL (log10), showed that (1) 450 nm blue light does not suppress the growth of GBS, even though its endogenous chromophore, granadaene, absorbs light in the 450 nm spectrum. (2) The addition of either of the two exogenous porphyrins, PPIX or CPIII, significantly suppressed GBS, indicating the importance of porphyrins in the antimicrobial action of blue light. (3) Adding exogenous FMN or FAD, two known absorbers of 450 nm light, minimally potentiated the bactericidal effect of blue light, again confirming that mere absorption of blue light by chromophores does not necessarily result in bacterial suppression. (4) Irradiation of GBS with or without NAD+ or NADH supplementation—two weak absorbers of 450 nm light—minimally suppressed GBS, indicating that a blue light-absorbing chromophore is essential for the bactericidal action of blue light. (5) Collectively, these findings show that in addition to the presence of a blue light-absorbing chromophore in bacteria, a chromophore with the right metabolic machinery and biochemical structure, capable of producing ROS, is necessary for 450 nm blue light to suppress GBS.

Correlations between sebaceous glands activity and porphyrins in the oily skin and hair and immediate effects of dermocosmetic formulations.

Oily skin and hair not only contain a large amount of sebum, but also exhibit other changes that compromise their physiology. The immediate effects of dermocosmetics are very important for adhesion to treatment. The aim of the present study was to characterize oily skin and scalp, to evaluate the correlation of sebum production with porphyrin counts and the immediate effects of topical formulations for sebum control. A total of 100 women aged 18-49 years were recruited. Sebaceous gland activity, sebum amount, stratum corneum water content (SCWC) transepidermal water loss (TEWL), skin gloss, amount of porphyrins and pores were determined in the face and SCWC, sebum amount, porphyrin count, and TEWL were also determined in the scalp. The immediate effects of formulations containing a guarana extract were determined after 2 hours of application. A correlation between sebaceous gland activity and presence of porphyrins in the frontal region of the face was detected. Low gloss values and large amounts of pores in the malar region were related to lower skin uniformity. High sebum values and low SCWC and porphyrin count were also observed in the vertex region. The studied formulations reduced the sebum content of face and scalp after 2 hours of application. Oily skin and hair showed high sebum values, which were correlated with porphyrin count and with the activity of sebaceous glands. Finally, the studied formulations had immediate reducing effects on sebum amounts on the skin and scalp.

Thermal unwinding of Polyadenylic·Polyuridylic acid complex with TMPyP4 porphyrin in aqueous solutions

Abstract The molecular mechanism of Poly(A)•Poly(U) (Polyadenylic•Polyuridylic acid) polyribonucleotide denaturation was studied through a combination of molecular dynamics (MD) simulations and UV–Vis-melting experiments. UV–Vis absorption spectra of Poly(A)•Poly(U) were measured at different temperatures (20–70 °C) both in the absence and presence of porphyrin-ligand TMPyP4 in equilibrated aqueous solutions (pH 7.0). Thermal behavior of double-stranded structure of Poly(A)•Poly(U) altered by formation of the ternary [Poly(A)•Poly(U)]*(TMPyP4)n complexes was studied with the help of a new semi-soft chemometrics procedure, based on the analyses of fractions of species in solution versus temperature. The melting temperature in the presence of porphyrin is 1.2 °C higher than that for pure polyribonucleotide, which indicates that porphyrin binding contributes to the suppression of transition between the native ordered structure of Poly(A)•Poly(U) and disordered state. MD simulations were performed for the binding of TMPyP4 to (rA)12•(rU)12 oligonucleotide to provide molecular-level insight into the mechanism of duplex dsRNA melting in the presence of TMPyP4. The results of MD simulations suggest a molecular mechanism of thermal stabilization of the native structure through the accommodation of TMPyP4 in double-stranded structure of (rA)12•(rU)12 oligonucleotide groove close to the end of the ordered region of stacked nucleobase pairs.

Polyethersulfone Mats Functionalized with Porphyrin for Removal of Para-nitroaniline from Aqueous Solution.

The dispersion of para-nitroaniline (p-NA) in water poses a threat to the environment and human health. Therefore, the development of functional adsorbents to remove this harmful compound is crucial to the implementation of wastewater purification strategies, and electrospun mats represent a versatile and cost-effective class of materials that are useful for this application. In the present study, we tested the ability of some polyethersulfone (PES) nanofibers containing adsorbed porphyrin molecules to remove p-NA from water. The functional mats in this study were obtained by two different approaches based on fiber impregnation or doping. In particular, meso-tetraphenyl porphyrin (H2TPP) or zinc(II) meso-tetraphenyl porphyrin (ZnTPP) were immobilized on the surface of PES fiber mats by dip-coating or added to the PES electrospun solution to obtain porphyrin-doped PES mats. The presence of porphyrins on the fiber surfaces was confirmed by UV–Vis spectroscopy, fluorescence measurements, and XPS analysis. p-NA removal from water solutions was spectrophotometrically detected and evaluated.

Porphyrin/sPEEK Membranes with Improved Conductivity and Durability for PEFC Technology

Advanced composite membranes have been obtained by incorporation of the meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) into a sulfonated poly(etheretherketone) (sPEEK). The presence of porphyrins in their monomeric, dimeric, and aggregated forms into the membrane ionic domains have been investigated by static and time-resolved spectroscopic techniques. In particular, we succeeded in modulating the percentage of the different porphyrin species present into the proton-conducting channels acting on the dye load in the range 0.35–5 wt % porphyrin/polymer. The nanostructure of all the composite membranes has been investigated by small-angle X-ray scattering. This latter shows how the presence of TPPS porphyrins into the membrane ionic domains induces a reorganization of polymer chains in a more stable and organized lamellar-like structure with respect to the pristine polymeric matrix. Finally, the composite membranes have been used as proton exchange membrane for fuel cells (PEFCs) technology. The presence o...

Heterocyclic Corrosion Inhibitors for J55 Steel in a Sweet Corrosive Medium.

The inhibitory effect of two heterocyclic porphyrin compounds, specifically 5,10,15,20-tetrakis(pentafluorophenyl)-21H,23H-porphyrin palladium(II) (PF-1) and 4,4′,4″,4‴-(porphyrin-5,10,15,20-tetrayl)tetrakis(benzoic acid) (PF-2), was studied in a sweet corrosion environment (3.5 wt % NaCl + CO2) on J55 steel by means of weight loss and electrochemical methods. Surface changes were studied using contact angle, scanning electrochemical microscopy (SECM), and atomic force microscopy (AFM) techniques. It was established that PF-2 showed the superlative inhibition efficiency of average of about 93% at 400 ppm concentration. The inductive behavior of the J55 steel surface in the presence of inhibitors was confirmed by SECM. The AFM further confirmed that the surface roughness was considerably decreased in the presence of porphyrins. The surface wettability of the steel was also investigated, and the results established the formation of a water-repellant layer on the surface when porphyrins are absorbed and layer became more hydrophobic with PF-2. Thermodynamics studies showed that the inhibition efficiencies of two compounds evaluated by all measurements follow the Langmuir adsorption isotherm.

Exploring the Direction of Charge Transfer in Porphyrin – PbSe Quantum Dot Hybrids

AbstractThe binding interaction of amine, thiol and carboxylic acid functionalized porphyrins to PbSe semiconductor quantum dots (QDs) has been studied by focusing on absorption and fluorescence of porphyrins in presence of PbSe QDs and absorption and fluorescence of PbSe QDs in presence of porphyrins. Only tetra‐carboxylic acid functionalized porphyrins appear to have significant binding to QDs. Fluorescence life time measurements show that the binding is dynamic rather than static, opposed to the case of metallic gold nanoparticles previously studied. QDs appear to reduce in size by dissolution, when they are exposed for longer times to porphyrins containing carboxylic acid functional groups. Transient absorption spectroscopy shows that charge transfer occurs uni‐directional from porphyrins to QDs as expected and not the other way round.

Isoprenoid Alcohols are Susceptible to Oxidation with Singlet Oxygen and Hydroxyl Radicals.

Isoprenoids, as common constituents of all living cells, are exposed to oxidative agents—reactive oxygen species, for example, singlet oxygen or hydroxyl radicals. Despite this fact, products of oxidation of polyisoprenoids have never been characterized. In this study, chemical oxidation of isoprenoid alcohols (Prenol-2 and -10) was performed using singlet oxygen (generated in the presence of hydrogen peroxide/molybdate or upon photochemical reaction in the presence of porphyrin), oxygen (formed upon hydrogen peroxide dismutation) or hydroxyl radical (generated by the hydrogen peroxide/sonication, UV/titanium dioxide or UV/hydrogen peroxide) systems. The structure of the obtained products, hydroxy-, peroxy- and heterocyclic derivatives, was studied with the aid of mass spectrometry (MS) and nuclear magnetic resonance (NMR) methods. Furthermore, mass spectrometry with electrospray ionization appeared to be a useful analytical tool to detect the products of oxidation of isoprenoids (ESI–MS analysis), as well as to establish their structure on the basis of the fragmentation spectra of selected ions (ESI–MS/MS analysis). Taken together, susceptibility of polyisoprenoid alcohols to various oxidizing agents was shown for the first time.Electronic supplementary materialThe online version of this article (doi:10.1007/s11745-015-4104-y) contains supplementary material, which is available to authorized users.

Interactions between cationic surfactants and 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin tetrasodium salt as seen by electric conductometry and spectroscopic techniques

Abstract The interaction between the anionic porphyrin 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin tetrasodium salt (Na4H2TPPS4) and alkyltrimethylammonium bromides (CnTAB), with different alkyl chain lengths (n = 12 and 16), in aqueous solutions have been studied by using electrical conductivity, potentiometry and spectroscopic (UV–vis and fluorescence) techniques. The effect of surfactant concentration in a concentration range involving the pre- and post-micelle region and temperature was evaluated. Interactions between surfactant and porphyrin lead to a three well-defined regions. At the lowest molar ratios, r = [CnTAB]/[Na4H2TPPS4] occur the disaggregation and deprotonation of porphyrins concomitantly with the formation of surfactant–porphyrin aggregates. These aggregates have a stoichiometry lower than the simple charge neutralization as due to the occurrence of multiple equilibria involving porphyrins. This also suggests that although electrostatic interactions are important, they are not the only driven-force for interaction. When surfactant is in excess (porphyrin saturation concentration The effect of porphyrin concentration and temperature on the micellization properties of surfactants was also analyzed, showing that temperature has no significant effect on the cmc of C16TAB. However, looking to the free energy of micellization the effect of temperature favours the micellization process, being such effect more pronounced for the most hydrophobic surfactant. This suggests that the degree of dissociation of counter ions in the micelle plays an important role on the micellization process in the presence of porphyrins.

Sulfuric Acid Assisted Extraction and Fractionation of Porphyrins From Heavy Petroleum Residuals With a High Content of Vanadium and Nickel

Primary porphyrin extracts were obtained from carbon tetrarchloride solutions of different heavy oil residuals with assistance of sulfuric acid. According to data of chromatographic separation of extracts porphyrinic fractions appear in amount of 13.0–24.2%. Based on UV/visible absorption spectroscopy the presence of porphyrins of etio and phyllo types mostly with rhodo and deoxophylloerythroetioporphyrins in lower amount was established. The content of porphyrins in obtained fractions was determined at the level of 15.3–44.8% of the total weight. It was shown that a higher concentration of porphyrins in sulfuric acid extracts occurs for the case of the high vanadium and nickel content and low amounts relation of asphaltenes to resins.

New Porphyrins/Calf Thymus DNA Complexes - Their Thermostability

The paper studies the melting parameters of the complexes of water soluble cationic 3N- and 4N-pyridyl porphyrins with different peripheral substituents (oxyethyl, buthyl, allyl, metallyl) with DNA. The results indicate that the presence of porphyrin changes the shape and parameters of DNA melting curve. The porphyrin concentration increase results in the increase of the melting temperature (Tm) and melting interval (ΔT) of DNA. With the porphyrin-DNA concentration ratio ν = 0.01, changes of melting temperature have not been observed. The melting intervals almost do not change upon the addition of the 4N- porphyrins, while the decrease of ΔT is observed in the presence of 3N-porphyrins. Because of the intercalation binding mechanism occurring in GC-rich regions of DNA, we assume that 3N-porphyrins intercalated in GC-rich regions, reduce the thermal stability of these sites, bringing them closer to the thermal stability of the AT-sites, which is the reason for the decrease in melting interval. While with the relative concentration ν = 0.01 for 4-N porphyrins the external binding mechanism “turns on” and destabilizing effect of porphyrins on GC-pairs compensated by their stabilizing effect on AT-pairs. As a result, no change in the melting parameters of DNA is observed upon complexation with these porphyrins.

Stability of bilayer lipid membrane in the presence of Co-containing metalloporphyrins

Stability of bilayer lipid membrane (BLM) in an electric field in the presence of Co-porphyrin in the solution surrounding BLM is investigated. We have shown that the presence of porphyrin in a solution reduces line tension of the pore edge and surface tension of BLM and increases the number of pores on the BLM. It is also shown that a decrease in the stability of BLM in the electric field in the presence of the porphyrin is a result of the reduction of line tension of the pore edge and increase in the number of pores.

A triazine functionalized porous organic polymer: excellent CO2storage material and support for designing Pd nanocatalyst for C–C cross-coupling reactions

One-pot bottom-up synthesis involving extended aromatic electrophilic substitution on to a pyrrole has been employed for the design of a novel triazine-functionalized porphyrin-based porous organic polymer, TPOP-1. Hydrothermal treatment of 4,4′,4′′-(1,3,5-triazine-2,4,6-triyl)tris(oxy)tribenzaldehyde and pyrrole in glacial acetic acid in the presence of FeCl3 leads to the formation of TPOP-1, which is a highly porous and robust material, and which exhibits a high surface area and bimodal pore sizes ranging from large micropores to mesopores. The presence of porphyrin and triazine functionality within the network structure enables formation of electron-donating basic N-sites at the surface of the porous organic framework and thus favors the adsorption of Lewis acidic CO2 molecules and decoration of the material by palladium nanoparticles at its surface to form Pd-TPOP-1. TPOP-1 showed good CO2 storage capacity (6.2 mmol g−1 or 27.3 wt% at 3 bar/273 K), suggesting its potential application in environmental clean-up. Moreover, this post Pd-functionalized material forms fine colloidal suspensions in organic solvent and exhibits high catalytic activity for Sonogashira cross-coupling of aryl halides with aryl alkynes under mild reaction conditions.

Preparation of gold nanoparticles of desired size and a study of their impact on the photosensitized generation of singlet oxygen in the aquatic phase

The effect of gold nanoparticles on the photooxidation of tryptophan in the presence of porphyrins immobilized on chitosan in the aquatic medium is studied. This reaction is used as a model to assess the sensitizing ability of porphyrins in the photogeneration of singlet oxygen, a process underlying photodynamic therapy, a promising method for treatment of cancer. Gold nanoparticles are prepared by reduction of gold cations with sodium borohydride in the presence of polyvinylpyrrolidone. The proposed technique enables to obtain gold nanoparticles with a very narrow size distribution.