Effect Of Zinc Cations On The Kinetics Of Supramolecular Assembly And The Chirality Of Porphyrin J-Aggregates

Dilute aqueous solutions of anionic meso-4-sulfonatophenyl-porphyrin (TPPS) extract zinc(ii) ions from glass or quartz surfaces at room temperature and efficiently form the corresponding metal complex (ZnTPPS). The partial or complete formation of ZnTPPS has been probed by UV/Vis spectroscopy and both static and time-resolved fluorescence. The source of zinc(ii) ions has been clearly identified through inductively coupled plasma optical emission spectrometry. The presence of increasing amounts of ZnTPPS slows down the rate of TPPS J-aggregate formation in acid solution. This influences the nucleation step and has a profound impact on the onset of chirality in these species. This evidence indicates the important role of this adventitious metal ion in the interpretation of various spectroscopic and kinetic data for the self-assembly of the TPPS porphyrin and provides some insights into controversial findings on their chirality. The use of this metal derivative as the starting compound for in situ formation of monomeric TPPS is suggested

Mechanism For Copper(II)-Mediated Disaggregation Of A Porphyrin J-Aggregate

J-aggregates of anionic meso-tetrakis(4-sulfonatophenyl)porphyrin form at intermediate pH (2.3–3.1) in the presence of NiSO₄ or ZnSO₄ (ionic strength, I.S. = 3.2 M). These aggregates convert to monomeric porphyrin units via metallation with copper(II) ions. The kinetics for the disassembly process, as monitored by UV/vis spectroscopy, exhibits zeroth-order behavior. The observed zeroth-order rate constants show a two-term dependence on copper(II) ion concentrations: linear and second order. Also observed is an inverse dependence on hydrogen ion concentration. Activation parameters have been determined for the disassembly process leading to ΔH^≠ = (+163 ± 15) kJ·mol⁻¹ and ΔS^≠ = (+136 ± 11) J·K⁻¹. A mechanism is proposed in which copper(II) cation is in pre-equilibrium with a reactive site at the rim of the J-aggregate. An intermediate copper species is thus formed that eventually leads to the final metallated porphyrin either through an assisted attack of a second metal ion or through a direct insertion of the metal cation into the macrocycle core

A qualitative study of the experiences of Iranian infertile couples after unsuccessful assisted reproductive technologies

Objectives: Assisted reproductive technologies (ARTs) give hope to some infertile couples; however, in vitro fertilization (IVF) is expensive and not subsidized by the Iranian state. More than 75% of IVF cycles in Iranian couples are unsuccessful. The aim of this paper is to describe the experiences of Iranian infertile couples after unsuccessful treatment. Materials and Methods: In this descriptive qualitative study, 36 participants including 29 Iranian infertile couples recruited after unsuccessful ART treatments, five infertility treatment team members and 2 relatives of infertile couples were interviewed at an Infertility Center in Northeastern Iran from April 2016 to June 2017. Data were collected using semi-structured, face-to-face interviews. Data analysis was carried out following Sandelowski. Results: Iranian infertile couples’ experiences following failed ART cycles are described. The findings presented here show that Iranian infertile couples experience stressors during treatment cycles and systemic challenges which may be unique to the Iranian cultural context. Conclusions: Iranian infertile couples face particular challenges related to the cultural context in which ARTs are delivered. Further exploration of the effects of culture on the experiences of failed ARTs needs to be considered by infertility clinics in Ira

Spreading factors of a globally invading coastal copepod

The Mediterranean Sea is one of the areas most affected by alien invasions, which are continuously increasing also due to intense human activities and environmental changes that favor the introduction of species previously unable to colonize the basin. This is the case of the copepods of the genus Pseudodiaptomus, first described in the Indian Ocean and considered one of the most resistant to unfavorable conditions but never recorded in the Mediterranean until 2011 though present in adjacent seas. Pseudodiaptomus marinus, in particular, is common in shallow marine-brackish waters and is one of the species often found in ballast waters and in aquaculture plants. Native of Japan, it has started spreading since 1950s and its populations have established in several harbours, eutrophic inlets and lagoons along the coasts of the Pacific and Indian Oceans. In the last few years, P. marinus has been increasingly reported in European Seas (Mediterranean Sea and North Sea). In this paper, we review the invasion history of this species with a special emphasis on its records in the Mediterranean Sea, and its occurrence and establishment in Sicilian waters. We also compare the biological traits and population dynamics of P. marinus with those of other representative of the genus and discuss about the possible mechanisms of introduction in new environments. Aim of our work is to understand the reasons of successful invasion of P. marinus and the environmental and biological factors that may lead to its further biogeographic expansion

Infertile couples' perceived needs after unsuccessful fertility treatment: A qualitative study

Introduction: Infertility is a major medical issue. Investigations and treatment of infertility are the beginning of a complex, time-consuming and stressful process for couples that may fail well. The present study explored the needs of infertile couples following treatment failure with Assisted Reproductive Technologies (ARTs). Methods: A descriptive qualitative study was conducted in an Iranian infertility center, in the Northeast of the country between April 2016 and June 2017. The researchers recruited 29 individuals including 9 couples, 9 women and two men with primary infertility through purposive sampling. The data were collected using semi-structured interviews and analyzed iteratively, using conventional content analysis with MAXQDA software. Results: The main concepts obtained from the data were classified into one theme titled: ""The need for support"" and four main categories along with their subcategories, and included the need for psychological support, the need for more useful information, the need for social support and the need to access to supplementary services. Conclusion: The findings show that following treatment failure, the infertile patients’ expressed needs and preferences were not met. Identifying and meeting their needs may help the infertile couples to deal with ARTs failure and to reach a decision about future treatment

Iranian infertile couples' strategies to manage social interactions after unsuccessful treatments with assisted reproductive technologies

Many infertile couples feel vulnerable after failed treatment cycles and find insensitive remarks or inappropriate support distressing. They fear that the stress of failed treatment cycles may affect their marriage and lead to marriage breakdown. This study explored the strategies a sample of infertile couples used to manage social interactions after unsuccessful treatment with assisted reproductive technologies. A descriptive qualitative study was conducted with 34 participants including nine infertile couples, nine infertile women and two infertile men with primary infertility, two relatives, and three fertility clinic staff. The participants were selected through purposive sampling at an infertility centre in Iran, between 2016 and 2017. Data were collected using semi-structured face-to-face interviews and analysed by qualitative content analysis approach. Participants found some social interactions after failed assisted reproductive treatment cycles to be distressing and painful. They described tolerating painful emotions which cause them sadness and sorrow as well as feeling embarrassed. As a result, they found they needed to maintain their adopting concealment strategies with their families through not permitting speculation, selective disclosure, not giving details and hiding the truth. This study showed that social interactions following failed assisted reproductive cycles can be upsetting for infertile couples. Couples use different strategies to manage potentially distressing social interactions. Healthcare providers and psychologists may provide a space for safe social interactions in order to help couples to use appropriate strategies in these circumstances

Intracellular fate and impact on gene expression of doxorubicin/cyclodextrin-graphene nanomaterials at sub-toxic concentration

The graphene road in nanomedicine still seems very long and winding because the current knowledge about graphene/cell interactions and the safety issues are not yet sufficiently clarified. Specifically, the impact of graphene exposure on gene expression is a largely unexplored concern. Herein, we investigated the intracellular fate of graphene (G) decorated with cyclodextrins (CD) and loaded with doxorubicin (DOX) and the modulation of genes involved in cancer-associated canonical pathways. Intracellular fate of GCD@DOX, tracked by FLIM, Raman mapping and fluorescence microscopy, evidenced the efficient cellular uptake of GCD@DOX and the presence of DOX in the nucleus, without graphene carrier. The NanoString nCounter™ platform provided evidence for 34 (out of 700) differentially expressed cancer-related genes in HEp-2 cells treated with GCD@DOX (25 µg/mL) compared with untreated cells. Cells treated with GCD alone (25 µg/mL) showed modification for 16 genes. Overall, 14 common genes were differentially expressed in both GCD and GCD@DOX treated cells and 4 of these genes with an opposite trend. The modification of cancer related genes also at sub-cytotoxic G concentration should be taken in consideration for the rational design of safe and effective G-based drug/gene delivery systems. The reliable advantages provided by NanoString® technology, such as sensibility and the direct RNA measurements, could be the cornerstone in this field

Reelin expression in human prostate cancer: a marker of tumor aggressiveness based on correlation with grade.

Reelin is a glycoprotein that plays a critical role in the regulation of neuronal migration during brain development and, since reelin has a role in the control of cell migration, it might represents an important factor in cancer pathology. In this study, 66 surgical specimens of prostate cancer were analyzed for reelin expression by immunohistochemical method. The reelin expression was correlated with Gleason score and individual Gleason patterns. Reelin expression was found in 39% prostate cancers. Stromal tissues, normal epithelial cells and prostate intraepithelial neoplasia (PIN) of any grade around and distant from cancer were always negative for reelin. Reelin was found in malignant prostatic epithelial glands of 50% cases Gleason score 10, 52% Gleason score 9, 56% Gleason score 8, 18% Gleason score 7, while no sample of prostate cancers with Gleason score 6 showed reelin expression (P=0,005). As reelin staining is frequently found in high Gleason score prostate cancers, we explored whether reelin expression is influenced by single Gleason patterns

Iranian infertile couples' strategies to manage social interactions after unsuccessful treatments with assisted reproductive technologies

Many infertile couples feel vulnerable after failed treatment cycles and find insensitive remarks or inappropriate support distressing. They fear that the stress of failed treatment cycles may affect their marriage and lead to marriage breakdown. This study explored the strategies a sample of infertile couples used to manage social interactions after unsuccessful treatment with assisted reproductive technologies. A descriptive qualitative study was conducted with 34 participants including nine infertile couples, nine infertile women and two infertile men with primary infertility, two relatives, and three fertility clinic staff. The participants were selected through purposive sampling at an infertility centre in Iran, between 2016 and 2017. Data were collected using semi-structured face-to-face interviews and analysed by qualitative content analysis approach. Participants found some social interactions after failed assisted reproductive treatment cycles to be distressing and painful. They described tolerating painful emotions which cause them sadness and sorrow as well as feeling embarrassed. As a result, they found they needed to maintain their adopting concealment strategies with their families through not permitting speculation, selective disclosure, not giving details and hiding the truth. This study showed that social interactions following failed assisted reproductive cycles can be upsetting for infertile couples. Couples use different strategies to manage potentially distressing social interactions. Healthcare providers and psychologists may provide a space for safe social interactions in order to help couples to use appropriate strategies in these circumstances