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Dimethyl sulfoxide (DMSO) is commonly used to dissolve water-insoluble drugs due to its dipolar and aprotic properties. It also serves as a vehicle in many pharmacological studies. However, it has been reported that DMSO can induce seizures in human patients, lower seizure threshold in vivo, and modulate ion receptors activities in vitro. Therefore, we investigated here the effect of 0.03 % and 0.06 % DMSO, which are 10-50 times lower than what usually employed in previous studies, in the 4-aminopyridine (4AP) model of epileptiform synchronization in male mouse brain slices. We found that 0.03 % and 0.06 % DMSO increase 4AP-induced ictal discharge rate, while 0.06 % DMSO decreases ictal discharge duration. Our results suggest that the effects of DMSO on neuronal excitability deserve further analysis and that investigators need to be aware of its confounding effect as a solvent, even at very low concentrations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Nano-patterning the semiconducting photoactive layer/back electrode interface of organic photovoltaic devices is a widely accepted approach to enhance the power conversion efficiency through the exploitation of numerous photonic and plasmonic effects. Yet, nano-patterning the semiconductor/metal interface leads to intertwined effects that impact the optical as well as the electrical characteristic of solar cells. In this work we aim to disentangle the optical and electrical effects of a nano-structured semiconductor/metal interface on the device performance. For this, we use an inverted bulk heterojunction P3HT:PCBM solar cell structure, where the nano-patterned photoactive layer/back electrode interface is realized by patterning the active layer with sinusoidal grating profiles bearing a periodicity of 300 nm or 400 nm through imprint lithography while varying the photoactive layer thickness (L PAL ) between 90 and 400 nm. The optical and electrical device characteristics of nano-patterned solar cells are compared to the characteristics of control devices, featuring a planar photoactive layer/back electrode interface. We find that patterned solar cells show for an enhanced photocurrent generation for a L PAL above 284 nm, which is not observed when using thinner active layer thicknesses. Simulating the optical characteristic of planar and patterned devices through a finite-difference time-domain approach proves for an increased light absorption in presence of a patterned electrode interface, originating from the excitation of propagating surface plasmon and dielectric waveguide modes. Evaluation of the external quantum efficiency characteristic and the voltage dependent charge extraction characteristics of fabricated planar and patterned solar cells reveals, however, that the increased photocurrents of patterned devices do not stem from an optical enhancement but from an improved charge carrier extraction efficiency in the space charge limited extraction regime. Presented findings clearly demonstrate that the improved charge extraction efficiency of patterned solar cells is linked to the periodic surface corrugation of the (back) electrode interface., Supplementary Information: The online version contains supplementary material available at 10.1007/s00339-023-06492-6., Competing Interests: Conflict of interestThe authors have no competing interests to declare that are relevant to the content of this article., (© The Author(s) 2023.)

Evidence that the gut microbiota plays a key role in the pathogenesis of Alzheimer's disease is already unravelling. The microbiota-gut-brain axis is a bidirectional communication system that is not fully understood but includes neural, immune, endocrine, and metabolic pathways. The progression of Alzheimer's disease is supported by mechanisms related to the imbalance in the gut microbiota and the development of amyloid plaques in the brain, which are at the origin of Alzheimer's disease. Alterations in the composition of the gut microbiome led to dysregulation in the pathways governing this system. This leads to neurodegeneration through neuroinflammation and neurotransmitter dysregulation. Neurodegeneration and disruption of the blood-brain barrier are frontiers at the origin of Alzheimer's disease. Furthermore, bacteria populating the gut microbiota can secrete large amounts of amyloid proteins and lipopolysaccharides, which modulate signaling pathways and alter the production of proinflammatory cytokines associated with the pathogenesis of Alzheimer's disease. Importantly, through molecular mimicry, bacterial amyloids may elicit cross-seeding of misfolding and induce microglial priming at different levels of the brain-gut-microbiota axis. The potential mechanisms of amyloid spreading include neuron-to-neuron or distal neuron spreading, direct blood-brain barrier crossing, or via other cells such as astrocytes, fibroblasts, microglia, and immune system cells. Gut microbiota metabolites, including short-chain fatty acids, pro-inflammatory factors, and neurotransmitters may also affect AD pathogenesis and associated cognitive decline. The purpose of this review is to summarize and discuss the current findings that may elucidate the role of gut microbiota in the development of Alzheimer's disease. Understanding the underlying mechanisms may provide new insights into novel therapeutic strategies for Alzheimer's disease, such as probiotics and targeted oligosaccharides., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Competing Interests: The authors declare that they have no conflicts of interest to disclose.

Characterized chiefly by hypereosinophilia and angioedema, Gleich syndrome is a rare disorder with unclear clinical and therapeutic findings. Other symptoms include increased IgM levels, weight gain, fever, and urticaria. Herein we review Gleich syndrome and assess clinical features, epidemiology, and treatment options. Thirty-two articles including case reports or case series of eosinophilic angioedema and Gleich syndrome were included. Data regarding patient age, gender, and history, clinical and biological manifestations, and treatment protocols were recorded. The most common clinical findings include recurrent or non-recurrent angioedema, fever, urticaria, weight gain, blood eosinophilia, and elevated immunoglobulin levels. Corticosteroid therapy is the mainstay of treatment. Gleich syndrome is a distinctive hypereosinophilic entity with a benign course and good response to systemic corticosteroids. More studies are needed to evaluate the pathophysiology of this syndrome and lead to better therapeutic options., (© 2020 the International Society of Dermatology.)

Importance: Scleromyxedema is a chronic disease with high morbidity and mortality and no definitive therapeutic guidelines., Objective: To review all available data on the efficacy and the safety of the available treatments of scleromyxedema and suggest a possible therapeutic approach., Evidence Review: We performed a systematic literature review in Pubmed/Medline, Embase, and Cochrane collaboration databases, searching for all articles since 1990 on the treatments of scleromyxedema, with no limits on participant age, gender, or nationality., Findings: Ninety-seven studies were included in this systematic review, of which one prospective, two retrospective, 70 case reports/case series, and 24 letters/correspondence/clinical image. Intravenous immunoglobulin (IVIG) was the most used first-line therapy based on its efficacy and its generally well-tolerated nature; most patients require continued treatment to remain in remission. Thalidomide and systemic glucocorticoids were mostly considered as second-line therapies and were given alone or in association with IVIG. Patients with severe or refractory disease were treated with autologous bone marrow transplantation, melphalan, or bortezomib with dexamethasone., Conclusions and Relevance: Consideration of patient comorbidities, disease distribution, clinician experience, and treatment accessibility is mandatory in every therapeutic approach of scleromyxedema., (© 2020 the International Society of Dermatology.)

Purpose: This work evaluates the microbial spectrum and antibiotic susceptibility pattern of endophthalmitis cases in a large tertiary referral center in the Midwestern United States., Methods: This retrospective case series included patients with clinically diagnosed endophthalmitis between April 14, 2006 and April 14, 2016, in whom ocular samples were submitted to the Microbiology Department at Indiana University. The patients were assessed by 11 vitreoretinal surgeons from 6 different sites in Indianapolis, including Indiana University and private practices, who receive patients from urban, suburban, and rural agricultural areas. Submitted specimens were cultured with the following media: blood agar, chocolate agar, MacConkey agar, and thioglycolate broth., Results: A total of 327 specimens from 295 patients were analyzed, with 96 (32.5%) samples from 90 (30.5%) patients meeting the criteria of confirmed growth. Of these 96 positive specimens, 83 (86.5%) organisms were identified as bacterial, and 13 (13.5%) were identified as fungal. Coagulase-negative Staphylococcus was the most common isolate (37.5%). Fifty gram-positive isolates and 10 gram-negative isolates underwent susceptibility testing. All 40 of the gram-positive isolates tested for vancomycin sensitivity were susceptible, whereas all 7 of the gram-negative isolates tested for ceftazidime sensitivity were susceptible., Conclusions: Empiric treatment with vancomycin and ceftazidime remains appropriate in most cases of endophthalmitis in the Midwestern United States, with 100% susceptibility of bacterial organisms tested with these antibiotics in this series. The high fungal culture rates in this study highlight the utility of obtaining vitreous cultures and potential need for antifungal agents in suspicious cases., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of the article., (© The Author(s) 2020.)

Background: Rosacea is linked to abnormalities of cutaneous vasculature and dysregulation of the inflammatory response. Recent reports on rosacea have shown a significant association with cardiovascular, gastrointestinal, and psychiatric diseases, all of which may affect morbidity and mortality among these patients., Objective: To review available data regarding comorbidities associated with rosacea, discuss their pathogenesis, and highlight the evaluation of affected patients., Methods: We performed a complete and systematic literature review in PubMed/Medline, Embase, and the Cochrane Collaboration databases, searching for all articles on possible associated diseases that have been reported with rosacea, with no limits on publication date, participant age, sex, or nationality., Results: A total of 29 studies were included in this systematic review, including 14 case-control, 8 cross-sectional, and 7 cohort studies. Statistically significant association with rosacea has been mostly demonstrated with depression (n = 117,848 patients), hypertension (n = 18,176), cardiovascular diseases (n = 9739), anxiety disorder (n = 9079), dyslipidemia (n = 7004), diabetes mellitus (n = 6306), migraine (n = 6136), rheumatoid arthritis (n = 4192), Helicobacter pylori infection (n = 1722), ulcerative colitis (n = 1424), and dementia (n = 1194)., Limitations: Limitations included the accuracy of the published data, potential patient selection, and possible confounding factors. The true nature of the drawn correlations is uncertain, and causality cannot be established., Conclusions: Rosacea is associated with a number of systemic disorders. Recognition of these conditions is critical to providing appropriate screening and management of affected patients., (Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)

Ultrasound-induced liquid-phase exfoliation (UILPE) is an established method to produce single- (SLG) and few-layer (FLG) graphene nanosheets starting from graphite as a precursor. In this paper we investigate the effect of the ultrasonication power in the UILPE process carried out in either N-methyl-2-pyrrolidone (NMP) or ortho-dichlorobenzene (o-DCB). Our experimental results reveal that while the SLGs/FLGs concentration of the NMP dispersions is independent of the power of the ultrasonic bath during the UILPE process, in o-DCB it decreases as the ultrasonication power increases. Moreover, the ultrasonication power has a strong influence on the lateral size of the exfoliated SLGs/FLGs nanosheets in o-DCB. In particular, when UILPE is carried out at ∼600 W, we obtain dispersions composed of graphene nanosheets with a lateral size of 180 nm, whereas at higher power (∼1000 W) we produce graphene nanodots (GNDs) with an average diameter of ∼17 nm. The latter nanostructures exhibit a strong and almost excitation-independent photoluminescence emission in the UV/deep-blue region of the electromagnetic spectrum arising from the GNDs' intrinsic states and a less intense (and strongly excitation wavelength dependent) emission in the green/red region attributed to defect states. Notably, we also observe visible emission with near-infrared excitation at 850 and 900 nm, a fingerprint of the presence of up-conversion processes. Overall, our results highlight the crucial importance of the solvent choice for the UILPE process, which under controlled experimental conditions allows the fine-tuning of the morphological properties, such as lateral size and thickness, of the graphene nanosheets toward the realization of luminescent GNDs.

Here we describe the fabrication of organic phototransistors based on either single or multifibers integrated in three-terminal devices. These self-assembled fibers have been produced by solvent-induced precipitation of an air stable and solution-processable perylene di-imide derivative, i.e., PDIF-CN2. The optoelectronic properties of these devices were compared to devices incorporating more disordered spin-coated PDIF-CN2 thin-films. The single-fiber devices revealed significantly higher field-effect mobilities, compared to multifiber and thin-films, exceeding 2 cm(2) V(-1) s(-1). Such an efficient charge transport is the result of strong intermolecular coupling between closely packed PDIF-CN2 molecules and of a low density of structural defects. The improved crystallinity allows efficient collection of photogenerated Frenkel excitons, which results in the highest reported responsivity (R) for single-fiber PDI-based phototransistors, and photosensitivity (P) exceeding 2 × 10(3) AW(-1), and 5 × 10(3), respectively. These findings provide unambiguous evidence for the key role played by the high degree of order at the supramolecular level to leverage the material's properties toward the fabrication of light-sensitive organic field-effect transistors combining a good operational stability, high responsivity and photosensitivity. Our results show also that the air-stability performances are superior in devices where highly crystalline supramolecularly engineered architectures serve as the active layer.

The technological exploitation of the extraordinary properties of graphene relies on the ability to achieve full control over the production of a high-quality material and its processing by up-scalable approaches in order to fabricate large-area films with single-layer or a few atomic-layer thickness, which might be integrated in working devices. A simple method is reported for producing homogenous dispersions of unfunctionalized and non-oxidized graphene nanosheets in N-methyl-2-pyrrolidone (NMP) by using simple molecular modules, which act as dispersion-stabilizing compounds during the liquid-phase exfoliation (LPE) process, leading to an increase in the concentration of graphene in dispersions. The LPE-processed graphene dispersion was shown to be a conductive ink. This approach opens up new avenues for the technological applications of this graphene ink as low-cost electrodes and conducting nanocomposite for electronics., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Enhancement in the ambipolar behavior of field-effect transistors based on an n-type polymer, P(NDI2OD-T2), is obtained by co-deposition with liquid-phase exfoliated graphene. This approach provides a prospective pathway for the application of graphene-based nanocomposites for logic circuits., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In organic field-effect transistors (OFETs) the electrical characteristics of polymeric semiconducting materials suffer from the presence of structural/morphological defects and grain boundaries as well as amorphous domains within the film, hindering an efficient transport of charges. To improve the percolation of charges we blend a regioregular poly(3-hexylthiophene) (P3HT) with newly designed N = 18 armchair graphene nanoribbons (GNRs). The latter, prepared by a bottom-up solution synthesis, are expected to form solid aggregates which cannot be easily interfaced with metallic electrodes, limiting charge injection at metal-semiconductor interfaces, and are characterized by a finite size, thus by grain boundaries, which negatively affect the charge transport within the film. Both P3HT and GNRs are soluble/dispersible in organic solvents, enabling the use of a single step co-deposition process. The resulting OFETs show a three-fold increase in the charge carrier mobilities in blend films, when compared to pure P3HT devices. This behavior can be ascribed to GNRs, and aggregates thereof, facilitating the transport of the charges within the conduction channel by connecting the domains of the semiconductor film. The electronic characteristics of the devices such as the Ion/Ioff ratio are not affected by the addition of GNRs at different loads. Studies of the electrical characteristics under illumination for potential use of our blend films as organic phototransistors (OPTs) reveal a tunable photoresponse. Therefore, our strategy offers a new method towards the enhancement of the performance of OFETs, and holds potential for technological applications in (opto)electronics.

We report on the fabrication of solution-processed organic phototransistors (OPTs) based on perylenebis(dicarboximide)s (PDIs). We found that the responsivity to the photoillumination depends on the transistor's channel length and that it can be tuned by varying the device geometry. The analysis of different morphologies of the active semiconducting layer revealed that single PDI fibers exhibit the higher photoresponse when compared to more poorly organized films. The highest responsivity value of 4.08 ± 1.65 × 10(5) A/W was achieved on a multifiber-based OPT. These findings represent a step forward toward the use of organic based phototransistors as photosensors., (© 2012 American Chemical Society)