Glutathione – linking cell proliferation to oxidative stress

Significance: The multifaceted functions of reduced glutathione (gamma-glutamyl-cysteinyl-glycine; GSH) continue to fascinate plants and animal scientists, not least because of the dynamic relationships between GSH and reactive oxygen species (ROS) that underpin reduction/oxidation (redox) regulation and signalling. Here we consider the respective roles of ROS and GSH in the regulation of plant growth, with a particular focus on regulation of the plant cell cycle. Glutathione is discussed not only as a crucial low molecular weight redox buffer that shields nuclear processes against oxidative challenge but also a flexible regulator of genetic and epigenetic functions. Recent Advances: The intracellular compartmentalization of GSH during the cell cycle is remarkably consistent in plants and animals. Moreover, measurements of in vivo glutathione redox potentials reveal that the cellular environment is much more reducing than predicted from GSH/GSSG ratios measured in tissue extracts. The redox potential of the cytosol and nuclei of non-dividing plant cells is about -300 mV. This relatively low redox potential is maintained even in cells experiencing oxidative stress by a number of mechanisms including vacuolar sequestration of GSSG. We propose that regulated ROS production linked to glutathione-mediated signalling events are the hallmark of viable cells within a changing and challenging environment. Critical Issues: The concept that the cell cycle in animals is subject to redox controls is well established but little is known about how ROS and GSH regulate this process in plants. However, it is increasingly likely that similar redox controls exist in plants, although possibly through different pathways. Moreover, redox-regulated proteins that function in cell cycle checkpoints remain to be identified in plants. While GSH-responsive genes have now been identified, the mechanisms that mediate and regulate protein glutathionylation in plants remain poorly defined. Future Directions: The nuclear GSH pool provides an appropriate redox environment for essential nuclear functions. Future work will function on how this essential thiol interacts with the nuclear thioredoxin system and nitric oxide to regulate genetic and epigenetic mechanisms. The characterization of redox-regulated cell cycle proteins in plants, and the elucidation of mechanisms that facilitate GSH accumulation in the nucleus are keep steps to unravelling the complexities of nuclear redox controls

Immune-related gene expression profiling after PD-1 blockade in non–small cell lung carcinoma, head and neck squamous cell carcinoma, and melanoma

Antibody targeting of the immune checkpoint receptor PD1 produces therapeutic activity in a variety of solid tumors, but most patients exhibit partial or complete resistance to treatment for reasons that are unclear. In this study, we evaluated tumor specimens from 65 patients with melanoma, lung nonsquamous, squamous cell lung or head and neck cancers who were treated with the approved PD1-targeting antibodies pembrolizumab or nivolumab. Tumor RNA before anti-PD1 therapy was analyzed on the nCounter system using the PanCancer 730-Immune Panel, and we identified 23 immune-related genes or signatures linked to response and progression-free survival (PFS). In addition, we evaluated intra- and interbiopsy variability of PD1, PD-L1, CD8A, and CD4 mRNAs and their relationship with tumor-infiltrating lymphocytes (TIL) and PD-L1 IHC expression. Among the biomarkers examined, PD1 gene expression along with 12 signatures tracking CD8 and CD4 T-cell activation, natural killer cells, and IFN activation associated significantly with nonprogressive disease and PFS. These associations were independent of sample timing, drug used, or cancer type. TIL correlated moderately (~0.50) with PD1 and CD8A mRNA levels and weakly (~0.35) with CD4 and PD-L1. IHC expression of PD-L1 correlated strongly with PD-L1 (0.90), moderately with CD4 and CD8A, and weakly with PD1. Reproducibility of gene expression in intra- and interbiopsy specimens was very high (total SD <3%). Overall, our results support the hypothesis that identification of a preexisting and stable adaptive immune response as defined by mRNA expression pattern is reproducible and sufficient to predict clinical outcome, regardless of the type of cancer or the PD1 therapeutic antibody administered to patients

Usefulness of multiparametric computerized tomography findings in the differential diagnosis of stroke mimics of epileptic origin: A preliminary study

Objetivo: Tras la activación del código ictus, hasta un 30% de los pacientes presentan cuadros imitadores del ictus, siendo la epilepsia el más frecuente. Evaluamos la utilidad de la TC cerebral multiparamétrica para la diferenciación de los déficit de origen comicial versus vascular. Material y métodos: Estudio observacional retrospectivo con recogida prospectiva de datos. Se revisan imágenes de TC multiparamétrica de pacientes atendidos como código ictus durante un año que finalmente fueron diagnosticados de etiología comicial. Resultados: N = 11 (varones 36%, edad media 74,5 a˜nos). Tres pacientes presentaban focalidad neurológica derecha, 4 focalidad izquierda y 4 afasia aislada. El tiempo máximo desde el inicio de la clínica hasta la realización de la TC multiparamétrica fue de 8,16 h. La TC perfusión fue normal en 2 pacientes. Nueve pacientes mostraron alargamiento/acortamiento del tiempo al pico (Tmáx), siendo los mapas de flujo y volumen variables. El electroencefalograma se realizó con un tiempo máximo de evolución desde el inicio de la clínica de 47,6 h. Cuatro registros mostraron hallazgos compatibles con estatus epiléptico, 2 actividad epileptiforme focal y los 5 restantes lentificación poscrítica ipsolateral a las anomalías de la TC perfusión. Conclusión: El alargamiento del tiempo al pico en una distribución cortical multilobar en ausencia de oclusión de gran vaso y con respeto de ganglios de la base ha resultado el parámetro más sensible para la diferenciación de estas entidades en nuestra serie. Consideramos que la TC cerebral multiparamétrica es una herramienta rápida, disponible y útil para el diagnóstico diferencial de síntomas neurológicos deficitarios de inicio brusco debidos a etiología comicial que son atendidos como código ictus.Objective: Thirty percent of the patients for whom code stroke is activated have stroke mimics, the most common being epilepsy. Our purpose was to evaluate the usefulness of multiparametric CT for differentiating between seizure-related symptoms and vascular events. Material and methods: We conducted a retrospective observational study; data were gathered prospectively during one year. We studied multiparametric CT images of patients admitted following code stroke activation and finally diagnosed with epilepsy. Results: The study included a total of 11 patients; 36% were men and mean age was 74.5 years. Three patients had right hemisphere syndrome, 4 displayed left hemisphere syndrome, and the remaining 4 had isolated aphasia. Maximum time from symptom onset to multiparametric CT study was 8.16 hours. Perfusion CT results were normal in 2 patients. Nine patients showed longer or shorter times to peak (Tmax); cerebral blood volume (CBV) and cerebral blood flow (CBF) maps varied. EEG was performed a maximum of 47.6 hours after symptom onset. Four patients showed findings compatible with status epilepticus, 2 displayed focal epileptiform activity, and 5 showed post-ictal slowing ipsilateral to perfusion CT abnormalities. Conclusion: The most sensitive parameter for differentiating between stroke and epilepsy in our series was increased time to peak in multilobar cortical locations in the absence of largevessel occlusion and basal ganglia involvement. Multiparametric CT is a fast, readily available, and useful tool for the differential diagnosis of acute-onset neurological signs of epileptic originin patients initially attended after code stroke activatio

Genome-Wide Screen of Genes Required for Caffeine Tolerance in Fission Yeast

Isabel A. Calvo et al...Background An excess of caffeine is cytotoxic to all eukaryotic cell types. We aim to study how cells become tolerant to a toxic dose of this drug, and the relationship between caffeine and oxidative stress pathways. Methodology/Principal Findings We searched for Schizosaccharomyces pombe mutants with inhibited growth on caffeine-containing plates. We screened a collection of 2,700 haploid mutant cells, of which 98 were sensitive to caffeine. The genes mutated in these sensitive clones were involved in a number of cellular roles including the H2O2-induced Pap1 and Sty1 stress pathways, the integrity and calcineurin pathways, cell morphology and chromatin remodeling. We have investigated the role of the oxidative stress pathways in sensing and promoting survival to caffeine. The Pap1 and the Sty1 pathways are both required for normal tolerance to caffeine, but only the Sty1 pathway is activated by the drug. Cells lacking Pap1 are sensitive to caffeine due to the decreased expression of the efflux pump Hba2. Indeed, ?hba2 cells are sensitive to caffeine, and constitutive activation of the Pap1 pathway enhances resistance to caffeine in an Hba2-dependent manner. Conclusions/Significance With our caffeine-sensitive, genome-wide screen of an S. pombe deletion collection, we have demonstrated the importance of some oxidative stress pathway components on wild-type tolerance to the drug.This work was supported by Direccion General de Investigacion of Spain Grant BFU2006-02610, and by the Spanish program Consolider-Ingenio 2010 Grant CSD 2007-0020, to E.H.Peer reviewe

Influenza and pneumococcal vaccine uptake among nursing home residents in Nottingham, England: a postal questionnaire survey

<p>Abstract</p> <p>Background</p> <p>Previous studies have shown influenza vaccine uptake in UK nursing home residents to be low. Very little information exists regarding the uptake of pneumococcal vaccine in this population. The formulation of policies relating to the vaccination of residents has been proposed as a simple step that may help improve vaccine uptake in care homes.</p> <p>Methods</p> <p>A postal questionnaire was sent to matrons of all care homes with nursing within the Greater Nottingham area in January 2006. Non respondents were followed up with up to 3 phone calls.</p> <p>Results</p> <p>30% (16/53) of respondents reported having a policy addressing influenza vaccination and 15% (8/53) had a policy addressing pneumococcal vaccination. Seasonal influenza vaccine coverage in care homes with a vaccination policy was 87% compared with 84% in care homes without a policy (p = 0.47). The uptake of pneumococcal vaccination was found to be low, particularly in care homes with no vaccination policy. Coverage was 60% and 32% in care homes with and without a vaccination policy respectively (p = 0.06). This result was found to be statistically significant on multivariate analysis (p = 0.03, R = 0.46)</p> <p>Conclusion</p> <p>The uptake of influenza vaccine among care home residents in the Nottingham region is relatively high, although pneumococcal vaccine uptake is low. This study shows that there is an association between pneumococcal vaccine uptake and the existence of a vaccination policy in care homes, and highlights that few care homes have vaccination policies in place.</p

Mitochondrial Dysfunction Increases Oxidative Stress and Decreases Chronological Life Span in Fission Yeast

Background: Oxidative stress is a probable cause of aging and associated diseases. Reactive oxygen species (ROS) originate mainly from endogenous sources, namely the mitochondria. Methodology/Principal Findings: We analyzed the effect of aerobic metabolism on oxidative damage in Schizosaccharomyces pombe by global mapping of those genes that are required for growth on both respiratory-proficient media and hydrogen-peroxide-containing fermentable media. Out of a collection of approximately 2700 haploid yeast deletion mutants, 51 were sensitive to both conditions and 19 of these were related to mitochondrial function. Twelve deletion mutants lacked components of the electron transport chain. The growth defects of these mutants can be alleviated by the addition of antioxidants, which points to intrinsic oxidative stress as the origin of the phenotypes observed. These respiration-deficient mutants display elevated steady-state levels of ROS, probably due to enhanced electron leakage from their defective transport chains, which compromises the viability of chronologically-aged cells. Conclusion/Significance: Individual mitochondrial dysfunctions have often been described as the cause of diseases or aging, and our global characterization emphasizes the primacy of oxidative stress in the etiology of such processes.This work was supported by Dirección General de Investigación of Spain Grant BFU2006-02610, and by the Spanish program Consolider-Ingenio 2010 Grant CSD 2007-0020 to E.H

Perceptions of change in the environment caused by the COVID-19 pandemic: implications for environmental policy

COVID-19 lockdown measures have impacted the environment with both positive and negative effects. However, how human populations have perceived such changes in the natural environment and how they may have changed their daily habits have not been yet thoroughly evaluated. The objectives of this work were to investigate (1) the social perception of the environmental changes produced by the COVID-19 pandemic lockdown and the derived change in habits in relation to i) waste management, energy saving, and sustainable consumption, ii) mobility, iii) social inequalities, iv) generation of noise, v) utilization of natural spaces, and, vi) human population perception towards the future, and (2) the associations of these potential new habits with various socio-demographic variables. First, a SWOT analysis identified strengths (S), weaknesses (W), opportunities (O), and threats (T) generated by the pandemic lockdown measures. Second, a survey based on the aspects of the SWOT was administered among 2370 adults from 37 countries during the period from February to September 2021. We found that the short-term positive impacts on the natural environment were generally well recognized. In contrast, longer-term negative effects arise, but they were often not reported by the survey participants, such as greater production of plastic waste derived from health safety measures, and the increase in e-commerce use, which can displace small storefront businesses. We were able to capture a mismatch between perceptions and the reported data related to visits to natural areas, and generation of waste. We found that age and country of residence were major contributors in shaping the survey participants ´answers, which highlights the importance of government management strategies to address current and future environmental problems. Enhanced positive perceptions of the environment and ecosystems, combined with the understanding that livelihood sustainability, needs to be prioritized and would reinforce environmental protection policies to create greener cities. Moreover, new sustainable jobs in combination with more sustainable human habits represent an opportunity to reinforce environmental policy

Young people’s perceptions of smartphone-enabled self-testing and online care for sexually transmitted infections: qualitative interview study

Background Control of sexually transmitted infections (STI) is a global public health priority. Despite the UK’s free, confidential sexual health clinical services, those at greatest risk of STIs, including young people, report barriers to use. These include: embarrassment regarding face-to-face consultations; the time-commitment needed to attend clinic; privacy concerns (e.g. being seen attending clinic); and issues related to confidentiality. A smartphone-enabled STI self-testing device, linked with online clinical care pathways for treatment, partner notification, and disease surveillance, is being developed by the eSTI2 consortium. It is intended to benefit public health, and could do so by increasing testing among populations which underutilise existing services and/or by enabling rapid provision of effective treatment. We explored its acceptability among potential users. Methods In-depth interviews were conducted in 2012 with 25 sexually-experienced 16–24 year olds, recruited from Further Education colleges in an urban, high STI prevalence area. Thematic analysis was undertaken. Results Nine females and 16 males participated. 21 self-defined as Black; three, mixed ethnicity; and one, Muslim/Asian. 22 reported experience of STI testing, two reported previous STI diagnoses, and all had owned smartphones. Participants expressed enthusiasm about the proposed service, and suggested that they and their peers would use it and test more often if it were available. Utilizing sexual healthcare was perceived to be easier and faster with STI self-testing and online clinical care, which facilitated concealment of STI testing from peers/family, and avoided embarrassing face-to-face consultations. Despite these perceived advantages to privacy, new privacy concerns arose regarding communications technology: principally the risk inherent in having evidence of STI testing or diagnosis visible or retrievable on their phone. Some concerns arose regarding the proposed self-test’s accuracy, related to self-operation and the technology’s novelty. Several expressed anxiety around the possibility of being diagnosed and treated without any contact with healthcare professionals. Conclusions Remote STI self-testing and online care appealed to these young people. It addressed barriers they associated with conventional STI services, thus may benefit public health through earlier detection and treatment. Our findings underpin development of online care pathways, as part of ongoing research to create this complex e-health intervention

Metabolic Adaptation in Transplastomic Plants Massively Accumulating Recombinant Proteins

BACKGROUND: Recombinant chloroplasts are endowed with an astonishing capacity to accumulate foreign proteins. However, knowledge about the impact on resident proteins of such high levels of recombinant protein accumulation is lacking. METHODOLOGY/PRINCIPAL FINDINGS: Here we used proteomics to characterize tobacco (Nicotiana tabacum) plastid transformants massively accumulating a p-hydroxyphenyl pyruvate dioxygenase (HPPD) or a green fluorescent protein (GFP). While under the conditions used no obvious modifications in plant phenotype could be observed, these proteins accumulated to even higher levels than ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), the most abundant protein on the planet. This accumulation occurred at the expense of a limited number of leaf proteins including Rubisco. In particular, enzymes involved in CO(2) metabolism such as nuclear-encoded plastidial Calvin cycle enzymes and mitochondrial glycine decarboxylase were found to adjust their accumulation level to these novel physiological conditions. CONCLUSIONS/SIGNIFICANCE: The results document how protein synthetic capacity is limited in plant cells. They may provide new avenues to evaluate possible bottlenecks in recombinant protein technology and to maintain plant fitness in future studies aiming at producing recombinant proteins of interest through chloroplast transformation

Human immunodeficiency virus/hepatits C virus coinfection in Spain: Elimination is feasible, but the burden of residual cirrhosis will be significant

Background We assessed the prevalence of antibodies against hepatitis C virus (HCV-Abs) and active HCV infection in patients infected with human immunodeficiency virus (HIV) in Spain in 2016 and compared the results with those of similar studies performed in 2002, 2009, and 2015. Methods The study was performed in 43 centers during October-November 2016. The sample was estimated for an accuracy of 2% and selected by proportional allocation and simple random sampling. During 2016, criteria for therapy based on direct-acting antiviral agents (DAA) were at least significant liver fibrosis, severe extrahepatic manifestations of HCV, and high risk of HCV transmissibility. Results The reference population and the sample size were 38904 and 1588 patients, respectively. The prevalence of HCV-Abs in 2002, 2009, 2015, and 2016 was 60.8%, 50.2%, 37.7%, and 34.6%, respectively (P trend <.001, from 2002 to 2015). The prevalence of active HCV in 2002, 2009, 2015, and 2016 was 54.0%, 34.0%, 22.1%, and 11.7%, respectively (P trend <.001). The anti-HCV treatment uptake in 2002, 2009, 2015, and 2016 was 23.0%, 48.0%, 59.3%, and 74.7%, respectively (P trend <.001). In 2016, HCV-related cirrhosis was present in 7.6% of all HIV-infected individuals, 15.0% of patients with active HCV, and 31.5% of patients who cleared HCV after anti-HCV therapy. Conclusions Our findings suggest that with universal access to DAA-based therapy and continued efforts in prevention and screening, it will be possible to eliminate active HCV among HIV-infected individuals in Spain in the short term. However, the burden of HCV-related cirrhosis will continue to be significant among HIV-infected individuals