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Κυριακή 4 Φεβρουαρίου 2018

Subcutaneous methotrexate in patients with moderate to severe psoriasis: a critical appraisal

Summary

Aim

Warren et al1 set out to assess the effect of an intensified dosing schedule of subcutaneous methotrexate in patients with moderate to severe chronic plaque psoriasis.

Setting and design

This is a prospective, double-blind, randomised (3:1), placebo-controlled study, conducted across 16 centres in Germany, France, the Netherlands, and the UK.

Study exposure

Methotrexate-naïve adults with a diagnosis of moderate to severe chronic plaque psoriasis for at least 6 months before baseline were randomly assigned to receive weekly subcutaneous injections of either methotrexate at a starting dose of 17.5 mg, or placebo for 16 weeks (first phase).Dose escalation to 22.5 mg/week was implemented after 8 weeks if patients did not achieve PASI 50. Treatment was combined with folic acid 5 mg/week. The first phase of the study was followed by an open-label period from 16-52 weeks (second phase), in which both groups received weekly methotrexate injections. At week 24, dose escalation to 22.5 mg/week was possible in patients not achieving PASI 50.

Outcomes

Psoriasis severity was measured using the PASI (Psoriasis Area and Severity Index). The authors also used two other psoriasis severity measures and two quality of life measures, looked at safety indices and performed a sub-study analysing paired skin biopsies at baseline and week 16 (histopathology, immunohistochemistry and expression of interleukin (IL)17A, interferon-γ and tumour necrosis factor-α).

Primary outcome measures

The primary outcome was the proportion of patients reaching PASI 75 at week 16.

Results

120 patients were included in this trial, most of whom were middle-aged white men with longstanding psoriasis and a mean BMI of 30.1 kg/m2. PASI 75 was achieved in 41% of patients receiving methotrexate vs. 10% of patients receiving placebo (RR 3.93, 95% CI 1.31–11.81; p=0.0026) at week 16. Subcutaneous methotrexate was generally well tolerated, with no serious adverse events related to this treatment over the 52-week study.

Conclusions

Warren et al conclude that the 52-week risk-benefit profile of subcutaneous methotrexate is favourable in patients with psoriasis.

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Oral retinoids and depression

Abstract

We are concerned about the content and possible misinterpretation of a research letter by Le Moigne et al. published on 19 June 2017 in the British Journal of Dermatology online.[1]

We share the concern expressed by the authors about possible psychiatric effects of oral retinoids. However, case reports rank low in the hierarchy of evidence, as a result of their inherent limitations, including publication bias and a lack of control groups.

This article is protected by copyright. All rights reserved.



A new mobile learning module using smartphone wallpapers in identification of medical fungi for medical students and residents

Abstract

Introduction

Medical students and residents will encounter many cutaneous fungal infections in medical practice. However, the training for identification of medical fungi has been insufficient due to limited lecture-based courses. The objective of this study was to evaluate the impact of using smartphone-based wallpapers in learning the microscopic morphology and colony characteristics of medical fungi for medical students and residents.

Methods

A smartphone-based wallpaper learning module using a wallpaper-changing software application (app) was introduced in this 3-week training course. Twenty-six participants were enrolled and divided into two groups: nondermatology trainees, including medical students and postgraduate year one (PGY-1) doctors who have not yet specialized, and dermatology trainees (dermatology residents). All of the participants completed a 3-week training course, and the effectiveness of the module was evaluated by pre- and post-course multiple-choice examinations.

Results

Both nondermatology and dermatology trainees scored significantly higher in post-course examinations than pre-course examinations (P < 0.001). The dermatology trainees performed better than nondermatology trainees in the pre-course examinations (P < 0.001). In the post-course examinations, no significant difference in scores was noted between dermatology and nondermatology trainees (P = 0.573).

Discussion

The smartphone-based wallpaper learning module was effective in helping medical students and residents learn and memorize morphologic characteristics of fungi. In comparison to conventional lecture-based learning, this new mobile module was more readily accessible and convenient for learners to engage in learning.



Disseminated actinomycetoma due to Nocardia wallacei

Abstract

Background

Actinomycetoma caused by Nocardia usually responds well to antibiotics. Emerging species of Nocardia, such as N. wallacei, can be a therapeutic challenge.

Aims

Confirm the therapeutic effectivity of linezolid in multidrug resistant Nocardia Wallacei actinomycetoma.

Materials and Methods

We evaluated the medical management of an 18-year-old man with multidrug resistant actinomycetoma of the left leg caused by N. transvalensis complex treated 17 years ago with linezolid 1200 mg a day. This bacteria was recently reclassified as Nocardia Wallacei by specific molecular biology technique.

Results

The infection was cured after 3 months of treatment; the patient remained asymptomatic for the past 17 years. No adverse effects were found.

Discussion

Frequently, strains of N. transvalensis complex have aminoglycoside resistance; in this case, we highlight the effectiveness of linezolid for the successful medical management of multidrug resistant actinomycetoma.

Conclusion

Linezolid can be an alternative for the treatment of multidrug resistant Nocardia Wallacei.



Treatment response to omalizumab in patients with refractory chronic spontaneous urticaria

Abstract

Background

Previous clinical trials have demonstrated the efficacy and safety of the anti-IgE monoclonal antibody omalizumab in chronic spontaneous urticaria (CSU) not responding to antihistamine treatment. The primary aim of our study was to describe the response patterns of patients with refractory CSU treated with omalizumab in a real-world clinical setting.

Methods

A retrospective analysis of medical records of 20 patients with refractory CSU was performed. Demographic, clinical, and laboratory features were retrieved and analyzed in correlation with treatment data.

Results

Mean age of our patient population was 54.5 years, while the majority were females (15/20 cases, 75%). Mean disease duration prior to omalizumab administration was 21.8 months. All patients had a history of chronic urticaria, refractory to high antihistamine and corticosteroid treatment, and responded favorably to omalizumab after administration of 1–5 doses of omalizumab; complete response was observed in 17/20 patients (85%) and well-controlled disease in the remaining 3/20 patients (15%). In a subset of cases (6/20, 30%), best response to omalizumab was achieved after interval administration of a 9-day course of methylprednisolone (total dose of 188 mg). Late response to omalizumab (after three-month treatment) was significantly correlated (P = 0.026) with shorter disease duration before initiation of omalizumab.

Conclusion

In the present series, omalizumab, either alone or in combination with a short-term course of corticosteroids, was highly effective in resolution of refractory CSU. Furthermore, disease duration prior to omalizumab had a significant effect on timing of response.



Occupational allergic contact dermatitis caused by antibiotics in healthcare workers – relationship with non-immediate drug eruptions

Summary

Background

Occupational allergic contact dermatitis (ACD) in healthcare workers (HCWs) is common, but systemic antibiotics are rarely reported as the cause.

Objectives

Characterize occupational ACD by handling systemic antibiotics.

Method

A retrospective analysis was performed of ACD caused by systemic antibiotics among HCWs patch tested between 2010 and 2016 with a series of systemic antibiotics.

Results

We studied 4 female nurses aged 28–47 years who developed ACD while working in surgical departments. They had eczema of the hands, and forearms or face, and 1 patient, who previously had exanthema caused by flucloxacillin, also developed a generalized rash following airborne exposure to systemic antibiotics. Patch tests showed positive reactions to ampicillin and cefazolin in 1 patient, to cefotaxime and ceftriaxone in 2 patients, and to several penicillins in another patient. Three patients also reacted to rubber allergens, fragrances, and/or preservatives. All patients admitted having direct and sporadic exposure to systemic antibiotic solutions. Avoidance resulted in a significant improvement of ACD, but 1 patient had to change job.

Conclusions

Occupational ACD caused by β-lactam antibiotics, particularly cephalosporins, is significant in HCWs. Cross-reactions between β-lactams are similar to those described in non-immediate drug eruptions. A relationship between systemic delayed drug hypersensitivity and ACD, as observed in 1 case, suggests that patients should avoid future use of the antibiotic to which they are sensitized.



Textile contact dermatitis caused by octylisothiazolinone in compression stockings



Toying with the Toolbox: How Metaphysics Can Still Make a Contribution

Abstract

Current analytic metaphysics has been claimed to be, at best, out of touch with modern physics, at worst, actually in conflict with the latter (Callender, in: French, Saatsi (eds) The continuum companion to the philosophy of science, Continuum, London, 2011; Ladyman and Ross Every thing must go: metaphysics naturalized, Oxford University Press, Oxford, 2007). While agreeing with some of these claims, it has been suggested that metaphysics may still be of service by providing a kind of 'toolbox' of devices that philosophers of science can access in order to help provide an interpretation of theories in fundamental physics (French and McKenzie in Eur J Anal Philos 8:42–59, 2012; see also French and McKenzie, in: Bigaj, Wuthrich (eds) Metaphysics in contemporary physics, Rodopi, Amsterdam, 2015). In this context it has been argued that 'standard' forms of dispositionalism simply cannot be sustained in the context of modern physics but that certain 'non-standard' views may provide the resources to help explicate the sense in which physics may be regarded as 'modally informed'. Here that suggestion will be further extended in order to consider the implications both with regard to the overall relevance of metaphysics given advances in science and for the prospects of a naturalised metaphysics more generally. In particular, this paper will focus on three concerns: (1) that the particular tools identified are not, in fact, 'scientifically disinterested' and thus that the distinction between 'naturalised' and 'non-naturalised' metaphysics is at best vague or poorly drawn; (2) that the usefulness of such tools depends on their being shaped to fit the relevant physics and thus the latter 'guts' metaphysics; (3) that if metaphysics does prove to be useful in this sense then we have no reason to scorn non-naturalised metaphysics to begin with.



Social Science as a Guide to Social Metaphysics?

Abstract

If we are sympathetic to the project of naturalising metaphysics, how should we approach the metaphysics of the social world? What role can the social sciences play in metaphysical investigation? In the light of these questions, this paper examines three possible approaches to social metaphysics: inference to the best explanation from current social science, conceptual analysis, and Haslanger-inspired ameliorative projects.



Phase 1/2 study assessing the safety and efficacy of dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced cutaneous melanoma

Abstract

The combination of dabrafenib and trametinib demonstrated encouraging antitumor activity and tolerability, at initial analysis, in Japanese patients with BRAF V600 mutant advanced melanoma warranting further investigation. This study evaluated the safety and tolerability, pharmacokinetics (PK) and preliminary efficacy of dabrafenib 150 mg b.i.d. plus trametinib 2 mg q.d. in Japanese patients with BRAF V600E/K mutant solid tumors (phase 1) and melanoma (phase 2). Phase 1 was primarily intended to assess safety and tolerability as assessed by adverse events (AE), and the primary end-point in phase 2 was to assess confirmed overall response rate (ORR). The secondary end-points in phase 1 included PK, confirmed/unconfirmed ORR and duration of response (DOR). The secondary end-points in phase 2 were PK, unconfirmed ORR, DOR, safety and tolerability. A total of 12 cutaneous melanoma patients were enrolled in the study (six in phase 1 and six in phase 2) and received the combination therapy of dabrafenib and trametinib. Common AE (≥50.0%) included pyrexia (75%), increased aspartate aminotransferase (67%), peripheral edema (50%) and nasopharyngitis (50%). The investigator-assessed ORR was reported in five patients (83%) in phase 1 and was also reported in five patients (83%; 95% confidence interval, 35.9–99.6; P < 0.0001) in phase 2. Plasma concentrations of both dabrafenib and trametinib seemed to a reach steady state by week 3. Overall, efficacy and PK properties for the dabrafenib plus trametinib combination in Japanese patients were comparable with those seen in global studies.



Efficacy of oral cholecalciferol on rhododendrol-induced vitiligo: A blinded randomized clinical trial

Abstract

Rhododendrol (RD), 4-(4-hydroxyphenyl)-2-butanol, inhibits melanin synthesis and has been used for skin-whitening cosmetic products. RD has been very effective in lightening skin pigmentation, but some persons have developed so-called RD vitiligo, in which vitiligo starts on the face, neck and hands where topical RD has been applied and even extended over skin areas where RD has not been applied. RD vitiligo lesions in some patients have lasted for years and have been resistant to conventional vitiligo treatments. We examined the effects of cholecalciferol on RD vitiligo in a blinded randomized clinical trial. Forty-eight female RD vitiligo patients were recruited for the trial and were randomized into two groups: the vitamin D (VD)-intervention group that received daily 5000 IU cholecalciferol for 5 months and the control group. Three blinded investigators scored vitiligo improvement by comparing photographic images of baseline and at 5-month observation. Serum 25(OH)D3 of RD vitiligo patients was not significantly different from age-matched healthy volunteers. Twenty-two in the VD-intervention group and 23 in the control group completed the 5-month observation. Serum 25(OH)D3 levels were significantly increased after the 5-month VD intervention, while the control group did not change. The improvement scores were significantly higher in the VD-intervention group than the control group. The improvement scores were positively correlated with the serum 25(OH)D3 levels after the 5-month intervention period but not before the treatment. This blinded randomized clinical trial showed favor in administrating 5000 IU cholecalciferol daily to RD vitiligo patients.



Case of atopic dermatitis concurrent with idiopathic thrombocytopenic purpura, whose serum thymus and activation-regulated chemokine level remained undetectable

Abstract

We report a 9-year-old Japanese female patient with atopic dermatitis associated with idiopathic thrombocytopenic purpura. She demonstrated high serum immunoglobulin (Ig)E and IgE specific to several environmental allergens, but extremely low serum thymus and activation-regulated chemokine (TARC) levels regardless of the disease progression. This case suggests platelets as the main source of serum TARC.



A novel image processing workflow for the in vivo quantification of skin microvasculature using dynamic optical coherence tomography

Abstract

Background

Currently, imaging technologies that can accurately assess or provide surrogate markers of the human cutaneous microvessel network are limited. Dynamic optical coherence tomography (D-OCT) allows the detection of blood flow in vivo and visualization of the skin microvasculature. However, image processing is necessary to correct images, filter artifacts, and exclude irrelevant signals. The objective of this study was to develop a novel image processing workflow to enhance the technical capabilities of D-OCT.

Materials and methods

Single-center, vehicle-controlled study including healthy volunteers aged 18-50 years. A capsaicin solution was applied topically on the subject's forearm to induce local inflammation. Measurements of capsaicin-induced increase in dermal blood flow, within the region of interest, were performed by laser Doppler imaging (LDI) (reference method) and D-OCT.

Results

Sixteen subjects were enrolled. A good correlation was shown between D-OCT and LDI, using the image processing workflow. Therefore, D-OCT offers an easy-to-use alternative to LDI, with good repeatability, new robust morphological features (dermal-epidermal junction localization), and quantification of the distribution of vessel size and changes in this distribution induced by capsaicin. The visualization of the vessel network was improved through bloc filtering and artifact removal. Moreover, the assessment of vessel size distribution allows a fine analysis of the vascular patterns.

Conclusion

The newly developed image processing workflow enhances the technical capabilities of D-OCT for the accurate detection and characterization of microcirculation in the skin. A direct clinical application of this image processing workflow is the quantification of the effect of topical treatment on skin vascularization.



Editor's Choice



Editorial board



Horizontal and vertical sections of scalp biopsy specimens from dermatomyositis patients with scalp involvement

Scalp involvement in dermatomyositis manifests as a pruritic eruption with erythema and scaling associated with nonscarring alopecia. We characterized the histologic features of scalp dermatomyositis using horizontal and vertical sections. Characteristic findings of scalp dermatomyositis include preserved follicular architecture, hair counts consistent with chronic telogen effluvium, telangiectasia and mucin.

Skin in the Game: Existing and Upcoming Physician Payment Models in Dermatology



Efficacy and Safety of Topical Oxymetazoline Cream 1.0% for Treatment of Persistent Facial Erythema Associated With Rosacea: Findings From the Two Phase 3, 29-Day, Randomized, Controlled REVEAL Trials

Most rosacea treatments targeting inflammatory lesions do not improve persistent facial erythema.Topical oxymetazoline hydrochloride cream 1.0% effectively reduced erythema versus vehicle in patients with moderate to severe persistent facial erythema of rosacea, with favorable tolerability.Topical oxymetazoline represents a new treatment option for patients with persistent erythema of rosacea.

Consultative Teledermatology in the Emergency Department and Inpatient Wards: A Survey of Potential Referring Providers.



Surgical treatment of axillary bromhidrosis by combining suction-curettage with subdermal undermining through a miniature incision

The suction-curettage technique has been widely applied in the treatment of axillary bromhidrosis. However, it can only moderately eradicate the malodor. From 2011 to 2013, we performed the suction-curettage procedure alone in 91 patients with primary axillary bromhidrosis (group A). From 2014 to 2016, we refined the suction-curettage technique by performing wide subdermal scissors undermining through a miniature incision in 80 patients (group B). Through a miniature incision at the inferior pole of the central axillary crease, the entire subcutaneous tissues containing apocrine glands were initially dissected with scissors within the axillary area and then the undermined apocrine glands were removed by suction-curettage.

Quality of life improvement after chest wall masculinization in female-to-male transgender patients: a prospective study using the BREAST-Q and body uneasiness test

Background: Chest reconstruction in many female-to-male (FTM) transgender individuals is an essential element of treatment for their gender dysphoria. In existing literature, there are very few longitudinal studies utilizing validated survey tools to evaluate patient reported outcomes surrounding this surgery. The purpose of our study is to prospectively evaluate patient reported satisfaction, improvement in body image, and quality of life following FTM chest wall reconstruction. Methods: Our study was a prospective analysis of FTM patients who underwent chest reconstruction by a single surgeon (C.A.) between April 2015 and June 2016.

Gasdermin C is Induced by Ultraviolet Light and Contributes to MMP-1 Expression via Activation of ERK and JNK Pathways

Matrix metalloproteinases (MMPs) comprise a family of zinc-dependent endopeptidases that are able to degrade extracellular matrix proteins [1–3]. MMP family members can be categorized into four different subfamilies: collagenases, stromelysins, gelatinases, and membrane-type MMPs [3–5]. MMPs play important roles in various physiological and pathological processes including developmental morphogenesis, tissue repair, skin aging, and tumor invasion. Expressions of some MMPs are regulated by diverse extracellular stimuli including UV, proinflammatory cytokines, and growth factors [4,6–9].

Diversity of circulating tumor cells in peripheral blood: Detection of heterogeneous BRAF mutations in a patient with advanced melanoma by single-cell analysis

Therapies targeting the MAPK signal pathway have been used to improve survival of patients with advanced melanoma [1]. However, many patients exhibit a short response and recurrence within several months after therapy, possibly related to heterogeneity arising due to genetic and epigenetic instability in melanoma cells. Circulating tumor cells (CTCs) released from primary or metastatic tumors are a non-invasive tool that could be used to characterize changes in tumors over time. Assuming that the CTC population represents the distributed tumor burden, characterization of these cells could provide a complementary sample for monitoring of tumor characteristics [2].

Coverage of the dorsal surface of a digit based on a pedicled free-style perforator flap concept

Reconstruction of the finger and thumb dorsum has been considered difficult due to the need for a thin and flexible flap, and the surrounding tissue is sometimes insufficient for a local flap. The purpose of this report is to describe our concept for finger and thumb dorsum reconstruction with free-style perforator flaps and our clinical experience with transfer of various perforator flaps.

“Reply - preventing the cheese-wire effect by combining steri-strips” and sutures for the management of lacerations in thin-skinned individuals. january 2017 volume 70, issue 1, pages 134-136.”

We read with interest the experimental results attaining to the technical tip of using the Steri-Strip/Suture combination. This method is indeed a useful technique in helping prevention of the cheese-wiring seen in frail skinned individuals although the application of this can be sometimes difficult, particularly if the wound is moist. The application of Steri-Strips can be quite problematic in the actively, or prone to, bleeding wound and in this instance, we would advocate the simple adjunct of using tincture of benzoin as a topical adhesive agent.

Improved photosynthetic efficacy of maize (Zea mays) plants with arbuscular mycorrhizal fungi (AMF) under high temperature stress

Publication date: Available online 4 February 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Sonal Mathur, Mahaveer P. Sharma, Anjana Jajoo
In this study, pot experiments were performed to investigate the effects of high temperature stress (44 °C) in maize plants colonized with and without arbuscular mycorrhizal fungi (AMF). Various parameters characterizing photosynthetic activity were measured in order to estimate the photosynthetic efficiency in maize plants. It was observed that density of active reaction centers of PSII, quantum efficiency of photosystem II (PSII), linear electron transport, excitation energy trapping, performance index, net photosynthesis rate increased in AMF (+) plants at 44 °C ± 0.2 °C. Efficiency of primary photochemical reaction (represented as Fv/Fo) increased in AMF (+) plants as compared to AMF (−) plants. AMF seems to have protected water splitting complex followed by enhanced primary photochemistry of PSII under high temperature. Basic morphological parameters like leaf width, plant height and cob number increased in AMF (+) plants as compared to AMF (−) plants. AMF (+) plants grew faster than AMF (−) plants due to larger root systems. Chl content increased in AMF (+) plants as compared to AMF (−) maize plants. AMF hyphae likely increased Mg uptake which in turn increased the total chlorophyll content in AMF (+) maize plants. This subsequently led to a higher production in photosynthate and biomass. Thus AMF (+) plants have shown better photosynthesis performance as compared to AMF (−) maize plants under high temperature stress.



Annonalide and derivatives: Semisynthesis, cytotoxic activities and studies on interaction of annonalide with DNA

Publication date: February 2018
Source:Journal of Photochemistry and Photobiology B: Biology, Volume 179
Author(s): Ricardo A. Marques, Akenaton O.C.V. Gomes, Maria V. de Brito, Ana L.P. dos Santos, Gladyane S. da Silva, Leandro B. de Lima, Fátima M. Nunes, Marcos C. de Mattos, Fátima C.E. de Oliveira, Cláudia do Ó Pessoa, Manoel O. de Moraes, Ângelo de Fátima, Lucas L. Franco, Marina de M. Silva, Maria Dayanne de A. Dantas, Josué C.C. Santos, Isis M. Figueiredo, Edeíldo F. da Silva-Júnior, Thiago M. de Aquino, João X. de Araújo-Júnior, Maria C.F. de Oliveira, A.A. Leslie Gunatilaka
The cytotoxic activity of the pimarane diterpene annonalide (1) and nine of its semisynthetic derivatives (2–10) was investigated against the human tumor cell lines HL-60 (leukemia), PC-3 (prostate adenocarcinoma), HepG2 (hepatocellular carcinoma), SF-295 (glioblastoma) and HCT-116 (colon cancer), and normal mouse fibroblast (L929) cells. The preparation of 2–10 involved derivatization of the side chain of 1 at C-13. Except for 2, all derivatives are being reported for the first time. Most of the tested compounds presented IC50s below 4.0 μM, being considered potential antitumor agents. The structures of all new compounds were elucidated by spectroscopic analyses including 2D NMR and HRMS. Additionally, the interaction of annonalide (1) with ctDNA was evaluated using spectroscopic techniques, and the formation of a supramolecular complex with the macromolecule was confirmed. Competition assays with fluorescent probes (Hoechst and ethidium bromide) and theoretical studies confirmed that 1 interacts preferentially via DNA intercalation with stoichiometric ratio of 1:1 (1:ctDNA). The ΔG value was calculated as −28.24 kJ mol−1, and indicated that the interaction process occurs spontaneously. Docking studies revealed that van der Walls is the most important interaction in 1-DNA and EB-DNA complexes, and that both ligands (1 and EB) interact with the same DNA residues (DA6, DA17 and DT19).

Graphical abstract

image


LuAG:Pr3+-porphyrin based nanohybrid system for singlet oxygen production: Toward the next generation of PDTX drugs

Publication date: February 2018
Source:Journal of Photochemistry and Photobiology B: Biology, Volume 179
Author(s): Kseniya Popovich, Kateřina Tomanová, Václav Čuba, Lenka Procházková, Iveta Terezie Pelikánová, Ivo Jakubec, Eva Mihóková, Martin Nikl
A highly prospective drug for the X-ray induced photodynamic therapy (PDTX), LuAG:Pr3+@SiO2-PpIX nanocomposite, was successfully prepared by a three step process: photo-induced precipitation of the Lu3Al5O12:Pr3+ (LuAG:Pr3+) core, sol–gel technique for amorphous silica coating, and a biofunctionalization by attaching the protoporphyrin IX (PpIX) molecules. The synthesis procedure provides three-layer nanocomposite with uniform shells covering an intensely luminescent core. Room temperature radioluminescence (RT RL) spectra as well as photoluminescence (RT PL) steady-state and time resolved spectra of the material confirm the non-radiative energy transfer from the core Pr3+ ions to the PpIX outer layer. First, excitation of Pr3+ ions results in the red luminescence of PpIX. Second, the decay measurements exhibit clear evidence of mentioned non-radiative energy transfer (ET). The singlet oxygen generation in the system was demonstrated by the 3′-(p-aminophenyl) fluorescein (APF) chemical probe sensitive to the singlet oxygen presence. The RT PL spectra of an X-ray irradiated material with the APF probe manifest the formation of singlet oxygen due to which enhanced luminescence around 530 nm is observed. Quenching studies, using NaN3 as an 1O2 inhibitor, also confirm the presence of 1O2 in the system and rule out the parasitic reaction with OH radicals. To summarize, presented features of LuAG:Pr3+@SiO2-PpIX nanocomposite indicate its considerable potential for PDTX application.

Graphical abstract

image


Predicted environmental concentration and fate of the top 10 most dispensed Australian prescription pharmaceuticals

Abstract

A basic environmental risk assessment was carried out for the top 10 dispensed pharmaceuticals in Melbourne, Australia, in contrast to the more commonly assessed measure of the most used drugs by physical mass. This allowed for the evaluation of compounds that had not previously been the subject of risk assessment. Estimations of the possible fate and behaviour of the target pharmaceuticals in sewage treatment plants were also made. The predicted removal rates of most drugs within standard sewage treatment were expected to be low, with the exception of the statins, which had high removal rates. Each pharmaceutical was predicted to be present in Melbourne wastewater at the nanogram per litre range or lower. All compounds were predicted to be of low toxicity risk, although it was not possible to model mixture effects. Atorvastatin and Irbesartan were also found to possess the potential to possibly bioaccumulate in the aquatic food chain but not to the extent that would require regulation or labelling.



Aqueous aggregation and stability of graphene nanoplatelets, graphene oxide, and reduced graphene oxide in simulated natural environmental conditions: complex roles of surface and solution chemistry

Abstract

Graphene-family nanomaterials (GFNs) exhibit universal applications and consequently will inevitably enter aquatic systems. However, both the fate and behavior of GFNs in aquatic environments have not been completely explored at field relevant conditions. Herein, we have systematically investigated the aqueous aggregation and stability of graphene nanoplatelets (GNPs), graphene oxide (GO), and reduced graphene oxide (RGO) under varied solution chemistry parameters (pH, divalent cations, and dissolved organic carbon (DOC)) during 21 days of incubation in simulated natural environmental conditions. Results indicate that pH values from 6 to 9 had a notable impact on the aqueous behaviors of the three GFNs. Divalent cations (Ca2+ and Mg2+) at the concentrations of 2.5 and 10 mM remarkably increased the extent of aggregation of the three GFNs and resulted in severe sedimentation, independently of surface chemical functionalization. The presence of only DOC ranging from 0.5 to 2 mg C/L significantly elevated the dispersion stability of GNPs and RGO in a dose-dependent manner, whereas no effects were observed on GO. Furthermore, DOC at the studied concentrations and surface functionality were insufficient to counterbalance the impact of the divalent cations. Direct visual and in situ observations further supported the conclusions on the effects of divalent cations or/and DOC. These findings further underline that the environmental behaviors of GFNs are controlled by the complex interplay between water chemistry parameters and GFN surface properties.



Organisms in wall ecosystems as biomonitors of metal deposition and bioavailability in urban environments

Abstract

Vegetated walls are common structures in urban environments, and aiming to test the hypothesis that the biogenic crusts and plant and animal communities inhabiting these vertical surfaces can be more reliable indicators of atmospheric metal deposition than plants or animals inhabiting urban soils, we analyzed the chemical composition of the wall crusts, moss cushions (Tortula muralis) and the shells, soft tissues and feces of the stonework snail Papillifera papillaris collected in three small towns in Tuscany (Central Italy). Crusts and mosses from the same stones or bricks indicated that Cd, Pb, and Zn are the main pollutants released by vehicular traffic, while Hg and Cu probably originate from other sources. The soft tissues of P. papillaris (purged of the gut contents) showed as well higher Cd, Pb, and Zn and lower Hg concentrations at more traffic-affected sites, while data from shells and feces suggested that this species probably ingests large amounts of Al, Cr, Fe, Mn, and Pb, and avoids eating mosses. Most lithophilic elements and Pb are scarcely absorbed in the snail digestive tract and soft tissues mainly accumulate Cd and essential elements such as Cu and Mn. This study definitively confirms the extraordinary Mn bioaccumulation in P. papillaris soft tissues and reports extraordinary Mn levels also in the shell. The shells also contain unusually high Cu, Fe, and Zn concentrations and this bioaccumulation likely remains after death, potentially providing a historical record of the snail exposure to metals over lifetime.