Intrinsic Photosensitivity Enhances Motility of T Lymphocytes

Intracellular metabolome elucidates the time-of-day-dependent response to hydrogen peroxide in salmonid gill epithelial cells

The internal timekeeping system regulates the daily cycle of physiological and behavioural changes in living organisms. This rhythmic phenomenon also influences cellular responses to reactive oxygen species, such as hydrogen peroxide (H2O2). However, the temporal interaction between H2O2 and fish mucosal cells is not well understood. This study examined the temporal variations of immunological and physiological responses to H2O2 in salmonid gill cells using the RTgill-W1 cell line. The results showed that gene expression levels varied during a 24-h cycle but did not exhibit rhythmicity. The presence of a 12-h light-dark cycle (12L:12D) signal increased gene expression levels compared to a 24-h dark cycle (0L:24D). To investigate whether the time of day affects the defences in gills, cells were exposed to H2O2 at two different times (Zeitgebertime 2, ZT2, or ZT14). Although significant expression changes were observed in genes related to stress and NF-κB signalling, only a limited time-dependent pattern of response to H2O2 was observed. The intracellular metabolome of gill cells was primarily composed of organic acid and derivatives, organoheterocyclic compounds, benzoids, organic oxygen and nitrogen compounds. Exposure to H2O2 at ZT2 led to significant changes in the metabolome compared to the control group, while no such changes were observed at ZT14. Within the control groups, the concentrations of 11 metabolites significantly varied between ZT2 and ZT14, with higher levels at ZT14. These metabolites were involved in arginine biosynthesis, amino acid metabolism, and nitrogen metabolism. In contrast, the level of 26 metabolites significantly varied between ZT2 and ZT14 in H2O2-exposed groups, with lower levels at ZT14. Comparing control and H2O2-exposed groups at ZT2, 38 metabolites were affected, primarily organic acid and derivatives and organic oxygen compounds. Functional annotation revealed that these altered metabolites were involved in 15 different pathways, with valine, leucine, and isoleucine biosynthesis being the most affected. This study reveals the presence of a time-dependent response to H2O2 in salmonid gill cells, which is reflected in the intracellular metabolome. The findings provide new insights into the temporal regulation of mucosal defences in fish.

HIV-associated photodermatitis in African populations

Photosensitive dermatoses are seen in 5% of HIV-infected persons. These include drug- and chemical-induced photoallergic and phototoxic reactions, chronic actinic dermatitis of HIV, photo lichenoid drug eruptions, and porphyria. Data on photodermatitis in HIV are limited to case reports and series. The pathogenesis is not completely understood and includes a th2 phenotype in HIV which results in impaired barrier function and resultant allergen sensitisation as well as immune dysregulation. The objective of this manuscript is to review the literature on the clinical phenotype, pathogenesis, role of photo and patch testing, outcomes, and treatment of photodermatitis in HIV in an African population.

Seasonal variation of cytomegalovirus disease in kidney transplant recipients

PURPOSE

Studies conducted in the northern United States found cytomegalovirus (CMV) disease after liver transplantation follows a seasonal pattern, with increased incidence in fall and winter. This has not been evaluated in kidney transplant recipients. Improved understanding of CMV seasonality may help guide use of preventative therapies.

METHODS

We evaluated adult patients receiving a kidney transplant at our center in Wisconsin from January 1, 1995 to December 31, 2018. CMV event was defined as quantifiable viral replication with clinical signs or symptoms suspicious for CMV per current consensus recommendations. Seasons were divided as follows: winter (December-February), spring (March-May), summer (June-August), and fall (September-November). The primary objective was to evaluate the annual distribution of CMV disease and determine whether this differed by season.

RESULTS

There were 6151 kidney transplants in the study period. A total of 913 patients had 1492 episodes of CMV. Median time from transplant to first detection was 5.51 months (interquartile range [IQR] 2.87-11.7). The observed overall incidence exceeded the expected incidence in winter (+.7%), spring (+5.5%), and fall (+3.4%) and was less than expected in summer (-9.5%) (p = .18). The incidence of CMV during summer, however, was 21% less than expected (p = .001) in recipients who were CMV positive (R+) at the time of transplantation. No such difference was observed in CMV negative recipients (R-; p = .58).

CONCLUSION

CMV after kidney transplant appears to be less common during the summer season in patients who were R+ at transplant but does not follow seasonal variation in R-. Reasons for this are unclear but are likely related to CMV-specific cell-mediated immunity. These findings may have clinical implications, particularly the use of non-pharmacologic strategies to improve response to antiviral therapy.

Unraveling Muscle Impairment Associated With COVID-19 and the Role of 3D Culture in Its Investigation

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been considered a public health emergency, extensively investigated by researchers. Accordingly, the respiratory tract has been the main research focus, with some other studies outlining the effects on the neurological, cardiovascular, and renal systems. However, concerning SARS-CoV-2 outcomes on skeletal muscle, scientific evidence is still not sufficiently strong to trace, treat and prevent possible muscle impairment due to the COVID-19. Simultaneously, there has been a considerable amount of studies reporting skeletal muscle damage in the context of COVID-19. Among the detrimental musculoskeletal conditions associated with the viral infection, the most commonly described are sarcopenia, cachexia, myalgia, myositis, rhabdomyolysis, atrophy, peripheral neuropathy, and Guillain-Barré Syndrome. Of note, the risk of developing sarcopenia during or after COVID-19 is relatively high, which poses special importance to the condition amid the SARS-CoV-2 infection. The yet uncovered mechanisms by which musculoskeletal injury takes place in COVID-19 and the lack of published methods tailored to study the correlation between COVID-19 and skeletal muscle hinder the ability of healthcare professionals to provide SARS-CoV-2 infected patients with an adequate treatment plan. The present review aims to minimize this burden by both thoroughly exploring the interaction between COVID-19 and the musculoskeletal system and examining the cutting-edge 3D cell culture techniques capable of revolutionizing the study of muscle dynamics.

Knowledge and perceptions of pharmacists' readiness during coronavirus pandemic: the case of United Arab Emirates

BACKGROUND

With the outbreak of Coronavirus infection (COVID-19), pharmacists play an important role in supporting local health during this emergency.

AIM

To assess the knowledge and to identify information sources regarding COVID-19 used by pharmacists, to investigate the active and public perceived roles of pharmacists, to explore the role of the pharmacy facilities and health authorities, and to identify barriers that would hinder pharmacists from performing their duties optimally in the United Arab Emirates.

METHODS

This descriptive cross-sectional online study was conducted in the UAE during the COVID-19 outbreak, from 18 May to 20 June 2020. A validated online questionnaire addressing participants' current knowledge about pandemics and COVID-19, source of information, and their perspectives of their role was used. Participants were licensed pharmacists practising in community and hospital pharmacies in UAE, academics, and pharmacy students.

RESULTS

Almost two-thirds of the participants (71.2%) were aged 18-30 years, with 76.2% females. Only 57.5% of participants believed that they got enough education about pandemics, and 88.3% of them followed on the latest coronavirus updates regarding treatments, and that is mainly from the World Health Organization reports (53.9%), followed by health authorities (44.8%). Two-thirds of participants (69.7%) had good/very good current knowledge regarding COVID-19. Knowledge of pharmacy students compared to pharmacists was significantly higher (p < 0.001).

CONCLUSION

The majority of pharmacists and pharmacy students reported that they have a major role in managing pandemics executed through the community pharmacies and that it is their role to ensure the availability of key medications. Policymakers and health authorities are called upon to train pharmacists in advance of emerging situations, supporting and helping them to optimally fulfill their role.

Pharmacists' readiness to deal with the coronavirus pandemic: Assessing awareness and perception of roles

Background

The 2019 Coronavirus infection (COVID-19) caused by a novel strain of coronavirus was detected in China in December 2019, and declared a public health emergency of international concern on January 30, 2020. Community pharmacists have an important role in supporting the local health emergency preparedness and response arrangements.

Objectives

To investigate pharmacists and pharmacy students' awareness and source of their information regard the management of the coronavirus pandemic, and their perspective of their role during this emergent situation.

Methods

This descriptive cross-sectional online survey study was conducted in Jordan during the COVID-19 outbreak (from 15 to 30 March 2020). A validated online questionnaire addressing participants' current awareness about epidemics/pandemics and COVID-19, source of information and their perspectives of their role. Data were analyzed using statistical package for social science (SPSS).

Results

Participants (n = 726) had a mean age of 26.9 (8.0) years with 71.9% females. Pharmacy students made 35.3% of the sample while the rest were pharmacists. Only 54.3% of participants believed that they got enough education about epidemics/pandemics, and 94.6% of them follow on the latest coronavirus updates on treatments, and that is mainly from the media (59.5%) followed by the World Health Organization reports (58.7%) and then the published researches (57%). Awareness score (out of 20) of pharmacists (n = 470) was significantly higher (p < 0.001) than that of students (n = 256). Better Awareness scores were also associated with higher age of participants, graduating from a public versus a private university, and attending more educational workshops.

Conclusion

The majority of pharmacists and pharmacy students reported that they have a major role in the management of epidemics/pandemics through the community pharmacies but the majority follow on the latest coronavirus updates from the media. This fact rings bills considering the numerous conflicting messages publicized during the pandemic through the media.

The viability of human cells irradiated with 470-nm light at various radiant energies in vitro

Blue light is known to be antimicrobial, but its effect on normal cutaneous and subcutaneous cells remains unclear. Therefore, we studied the effect of 470-nm light on the viability of adult and neonatal human dermal fibroblasts, Jurkat T-cells, and THP-1 monocytes in vitro. Each culture was irradiated with 0, 3, 55, or 110 J/cm² of 470-nm light and subjected to trypan blue assay to ascertain viability. Further, MTT, neutral red, and fluorescence assays of fibroblasts were performed, and cell morphology visualized using bright field and fluorescence microscopy. At each dose and in each of the four cell lines, there was no significant difference in cell concentration between irradiated and non-irradiated cultures, even though irradiation with 55 J/cm² or 110 J/cm² slightly decreased cell count. Light microscopy showed progressive morphological changes in the fibroblasts as energy fluence increased from 55 to 110 J/cm². Irradiation at 3 J/cm² produced a slight but non-significant increase in the viability of Jurkat T-cells and THP-1 monocytes. In contrast, at 110 J/cm² radiant exposure, irradiation slightly decreased the viability of all four cells. While 3 J/cm² appears stimulatory, our finding that 110 J/cm² produces a slight decrease in viability and engenders morphological changes in fibroblasts, suggesting that such high doses should be avoided in blue light treatments.

Better preventing and mitigating the effects of Covid-19

Currently, there are no proven medical treatments against SARS-CoV-2, the virus responsible for Covid-19. In addition to the all important public health measures needed to prevent the spread of this disease, a number of strategies related to our exposome are recommended herein, to better prevent and mitigate the effects of a SARS-CoV-2 infection through enhancement of our immune system and reduction of inflammation.

Quantitative Phase Dynamics of Cancer Cell Populations Affected by Blue Light

Increased exposition to blue light may induce many changes in cell behavior and significantly affect the critical characteristics of cells. Here we show that multimodal holographic microscopy (MHM) within advanced image analysis is capable of correctly distinguishing between changes in cell motility, cell dry mass, cell density, and cell death induced by blue light. We focused on the effect of blue light with a wavelength of 485 nm on morphological and dynamical parameters of four cell lines, malignant PC-3, A2780, G361 cell lines, and the benign PNT1A cell line. We used MHM with blue light doses 24 mJ/cm2, 208 mJ/cm2 and two kinds of expositions (500 and 1000 ms) to acquire real-time quantitative phase information about cellular parameters. It has been shown that specific doses of the blue light significantly influence cell motility, cell dry mass and cell density. These changes were often specific for the malignant status of tested cells. Blue light dose 208 mJ/cm2 × 1000 ms affected malignant cell motility but did not change the motility of benign cell line PNT1A. This light dose also significantly decreased proliferation activity in all tested cell lines but was not so deleterious for benign cell line PNT1A as for malignant cells. Light dose 208 mJ/cm2 × 1000 ms oppositely affected cell mass in A2780 and PC-3 cells and induced different types of cell death in A2780 and G361 cell lines. Cells obtained the least damage on lower doses of light with shorter time of exposition.

Hypothesis: bipolar disorder is an Epstein-Barr virus-driven chronic autoimmune disease - implications for immunotherapy

Bipolar disorder (BD) is a chronic disease characterised by episodes of major depression and episodes of mania or hypomania, with a worldwide prevalence of 2.4%. The cause of BD is unknown. Here, I propose the hypothesis that BD is a chronic autoimmune disease caused by Epstein–Barr virus (EBV) infection of autoreactive B cells. It is postulated that EBV‐infected autoreactive B cells accumulate in the brain where they provide costimulatory survival signals to autoreactive T cells and differentiate into plasma cells producing pathogenic autoantibodies targeting brain components such as the N‐methyl‐D‐aspartate receptor. It is also proposed that the accumulation of EBV‐infected autoreactive B cells in the brain is a consequence of a genetically determined defect in the ability of CD8⁺ T cells to control EBV infection. The theory is supported by studies indicating that autoimmunity, EBV infection and CD8⁺ T‐cell deficiency all have roles in the pathogenesis of BD. According to the hypothesis, BD should be able to be treated by EBV‐specific T‐cell therapy and to be prevented by vaccination against EBV in early childhood. Exposure to sunlight or appropriate artificial light should also be beneficial in BD by augmenting CD8⁺ T‐cell control of EBV infection.

Upregulation of calcitonin gene-related peptide, neuronal nitric oxide synthase, and phosphorylated extracellular signal-regulated kinase 1/2 in the trigeminal ganglion after bright light stimulation of the eye in rats

Bright light stimulation of the eye activates trigeminal subnucleus caudalis (Vc) neurons in rats. Sensory information is conveyed to the Vc via the trigeminal ganglion (TG). Thus, it is likely that TG neurons respond to photic stimulation and are involved in photic hypersensitivity. However, the mechanisms underlying this process are unclear. Therefore, the hypothesis in this study is bright light stimulation enhances the excitability of TG neurons involved in photic hypersensitivity. Expressions of calcitonin gene-related peptide (CGRP) and neuronal nitric oxide synthase (nNOS) were significantly higher in TG neurons from 5 min to 12 h after photic stimulation of the eye. Phosphorylation of extracellular signal-regulated kinase1/2 (pERK1/2) was enhanced in TG neurons within 5 min after photic stimulation, while pERK1/2 immunoreactivity in satellite glial cells (SGCs) persisted for more than 12 h after the stimulus. Activation of SGCs was observed from 5 min to 2 h. Expression of CGRP, nNOS, and pERK1/2 was observed in small and medium TG neurons, and activation of SGCs and pERK1/2-immunoreactive SGCs encircling large TG neurons was accelerated after stimulation. These results suggest that upregulation of CGRP, nNOS, and pERK1/2 within the TG is involved in photic hypersensitivity.

Human and Murine Evidence for Mechanisms Driving Autoimmune Photosensitivity

Ultraviolet (UV) light is an important environmental trigger for systemic lupus erythematosus (SLE) patients, yet the mechanisms by which UV light impacts disease are not fully known. This review covers evidence in both human and murine systems for the impacts of UV light on DNA damage, apoptosis, autoantigen exposure, cytokine production, inflammatory cell recruitment, and systemic flare induction. In addition, the role of the circadian clock is discussed. Evidence is compared in healthy individuals and SLE patients as well as in wild-type and lupus-prone mice. Further research is needed into the effects of UV light on cutaneous and systemic immune responses to understand how to prevent UV-light mediated lupus flares.

Antimicrobial blue light inactivation of pathogenic microbes: State of the art

As an innovative non-antibiotic approach, antimicrobial blue light in the spectrum of 400-470nm has demonstrated its intrinsic antimicrobial properties resulting from the presence of endogenous photosensitizing chromophores in pathogenic microbes and, subsequently, its promise as a counteracter of antibiotic resistance. Since we published our last review of antimicrobial blue light in 2012, there have been a substantial number of new studies reported in this area. Here we provide an updated overview of the findings from the new studies over the past 5 years, including the efficacy of antimicrobial blue light inactivation of different microbes, its mechanism of action, synergism of antimicrobial blue light with other angents, its effect on host cells and tissues, the potential development of resistance to antimicrobial blue light by microbes, and a novel interstitial delivery approach of antimicrobial blue light. The potential new applications of antimicrobial blue light are also discussed.

MTA promotes chemotaxis and chemokinesis of immune cells through distinct calcium-sensing receptor signaling pathways

Mineral trioxide aggregate (MTA) has been introduced as a choice material for regenerative dentistry. To date, the diverse biological activities of MTA, including its anti-inflammatory effects, have been extensively discussed. However, there is limited insight into the link between MTA and immune cell migration. In this study, we report the role of MTA in enhancing both chemotactic and chemokinetic immune cell migration through distinct signaling pathways. By using versatile live imaging techniques, we demonstrated that MTA-mediated CaSR activation induced diverse downstream pathways to govern cell migratory capacity. In this context, Cdc42 generates cytoskeleton-driven cellular protrusions to steer directional cell migration (chemotaxis) whereas Ca²⁺-calmodulin dependent myosin light chain kinase induces cell contractility that plays an important role in speeding up the average migration speed (chemokinesis). Our findings illuminate an unrecognized role for MTA and the related CaSR signaling network in immune cell migration, providing evidence that can drive development of novel approaches to immunological therapy.