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The interaction of light with natural matter leads to a plethora of photosensitized reactions. These reactions cause the degradation of biomolecules, such as DNA, lipids, proteins, being therefore detrimental to the living organisms, or they can also be beneficial by allowing the treatment of several diseases by photomedicine. Based on the molecular mechanistic understanding of the photosensitization reactions, we propose to classify them in four processes: oxygen-dependent (type I and type II processes) and oxygen-independent [triplet-triplet energy transfer (TTET) and photoadduct formation]. In here, these processes are discussed by considering a wide variety of approaches including time-resolved and steady-state techniques, together with solvent, quencher, and scavenger effects. The main aim of this survey is to provide a description of general techniques and approaches that can be used to investigate photosensitization reactions of biomolecules together with basic recommendations on good practices. Illustration of the suitability of these approaches is provided by the measurement of key biomarkers of singlet oxygen and one-electron oxidation reactions in both isolated and cellular DNA. Our work is an educational review that is mostly addressed to students and beginners.

Interactions of DNA with structural proteins such as histones, regulatory proteins and enzymes play a crucial role in major cellular processes such as transcription, replication and repair. The in vivo mapping and characterization of the binding sites of the involved biomolecules are of primary importance for a better understanding of genomic deployment that is implicated in tissue and developmental stage-specific gene expression regulation. The most powerful and commonly used approach to date is immunoprecipitation of chemically cross-linked chromatin (XChIP) coupled with sequencing analysis (ChIP-seq). While the resolution and the sensitivity of the high-throughput sequencing techniques have been constantly improved, little progress has been achieved in the cross-linking step. Because of its low efficiency, the use of the conventional UVC lamps remains very limited while the formaldehyde method was established as the "gold standard" cross-linking agent. Efficient biphotonic cross-linking of directly interacting nucleic acid-protein complexes by a single short UV laser pulse has been introduced as an innovative technique for overcoming limitations of conventionally used chemical and photochemical approaches. In this survey, the main available methods including the laser approach are critically reviewed for their ability to generate DNA-protein cross-links in vitro model systems and cells.

Climate change has been labeled one of the most significant threats to patient health. Advanced practice registered nurses must acquire adequate preparatory education to care for patients during climate change. They would benefit from implementing climate change concepts to provide safe and quality care for patients. This article aims to discuss integrating climate change concepts into advanced practice nurses curricula by applying the National Organization of Nurse Practitioner Faculties' competencies.

Antiretroviral therapies for HIV may cause systemic toxicities when coadministered with corticosteroids. Potential drug-drug interactions may occur, leading to iatrogenic Cushing syndrome or adrenal insufficiency. This article highlights the drug-drug interactions of antiretroviral therapies with corticosteroids. Practice implications are discussed.

This article aims to report the role of the quality improvement radiology nurse. The quality improvement nurse must possess the knowledge, skills, and attitudes to deliver safe and quality care. There is a lack of guidance that describes the role of the quality improvement radiology nurse. The Quality Education for Nurses Framework and Kotter's model both provide a foundation for describing the role of the quality improvement radiology nurse. More research is needed to analyze the role of the quality improvement radiology nurse. Implications to nursing practice, education, and research are discussed.

Molecular oxygen sensitizes DNA to damage induced by ionizing radiation, Fenton-like reactions, and other free radical-mediated reactions. It rapidly converts carbon-centered radicals within DNA into peroxyl radicals, giving rise to a plethora of oxidized products consisting of nucleobase and 2-deoxyribose modifications, strand breaks and abasic sites. The mechanism of formation of single oxidation products has been extensively studied and reviewed. However, much evidence shows that reactive peroxyl radicals can propagate damage to vicinal components in DNA strands. These intramolecular reactions lead to the dual alteration of two adjacent nucleotides, designated as tandem or double lesions. Herein, current knowledge about the formation and biological implications of oxidatively generated DNA tandem lesions is reviewed. Thus far, tandem lesions have been reported to involve contiguous thymine and guanine modifications, which as a good example, is explained by the initial formation of a thymine peroxyl radical followed by addition to a 5'-flanking guanine. Proper biomolecular processing is impaired by several tandem lesions making them refractory to base excision repair and potentially more mutagenic.

Background: Research findings have revealed that some students are not prepared to face the challenges associated with online learning, and attrition rates have been found to be a major concern. This review aimed to investigate the learning characteristics nursing students need before enrolling in online learning to ensure success. Method: Electronic databases were searched to investigate the learning characteristics of students for the literature review. Results: The search identified a final selection of 24 quantitative and qualitative studies. Readiness to learn, self-efficacy, motivation, persistence, and autonomy are learning characteristics for students to possess when enrolling in online learning environments. However, not all students have these learning characteristics; thus, their learning needs should be assessed. Conclusion: More mixed-methods and randomized control trial studies are needed to examine online students' learning characteristics. Nurse educators must evaluate their students to investigate whether online learning fits their learning goals. [ J Nurs Educ . 2021;60(4):209–215.]

Ozone is a major component of air pollution and carries potentially mutagenic and harmful affects to health. The oxidation of isolated calf thymus DNA (CT-DNA) led to the nearly quantitative loss of normal DNA 2'-deoxyribonucleosides in the following order: T > G > C ≫ A. The major modification of pyrimidines (T, C, and 5-methylcytosine (5mC)) was the corresponding 5-hydroxyhydantoin derivative after complete digestion of DNA to its component 2'-deoxyribonucleosides. The oxidation of 5mC was 2.5-fold more susceptible than C considering the relative mole fraction of 5mC to C in CT-DNA. Other common oxidation products of pyrimidines (e.g., 5,6-dihydroxy-5,6-dihydropyrimidines, the so-called pyrimidine 5,6-glycols) were formed with a lower yield than 5-hydroxyhydantoin derivatives. In addition, several common oxidation products of G were observed (e.g., 8-oxo-7,8-dihydroguanine (8oxoG)) albeit with relatively minor yields. The sum of individual products was notably less than the loss of 2'-deoxyribonucleosides from which they were derived. In a search for additional products, we discovered the formation of pyrimidine ring fragments, predominantly N-formamide and N-urea, which were measured as a dinucleotide next to a nonmodified nucleotide upon partial digestion of oxidized DNA. Interestingly, the latter fragments were also observed in dinucleotides containing 8oxoG, indicating the formation of tandem lesions during ozonolysis of DNA. The oxidation of DNA upon exposure to ozone can be explained by reactions of an intermediate ozonide. These studies underline the complexity of ozone-induced DNA damage and provide valuable information to assess the formation of this damage in cellular DNA.

The UVA and UVB components of sunlight can produce three classes of bipyrimidine DNA photolesions [cyclobutane pyrimidine dimers (CPDs), pyrimidine (6‐4) pyrimidone photoproducts (6‐4PPs) and related Dewar valence isomers (DewarPPs)]. The UVA/UVB ratio of sunlight is high in winter and low in summer in the Northern Hemisphere. Since UVB radiation produces 6‐4PPs and UVA radiation converts them into DewarPPs through photoisomerization, it is expected that there may be differences in the photoisomerization of 6‐4PPs between summer and winter, although that has never been documented. To determine that, isolated DNA was exposed to natural sunlight for 8 h in late summer and in winter, and absolute levels of the three classes of photolesions were quantified using calibrated ELISAs. It was found that sunlight produces CPDs and 6‐4PPs in DNA at a ratio of about 9:1 and converts approximately 80% of 6‐4PPs into DewarPPs within 3 h. Moreover, photoisomerization is more efficient in winter than in late summer after sunlight irradiation for the same duration, at similar solar UV doses and with the same induction level of CPDs. These results demonstrate that seasonal differences in the UVA/UVB ratio influence the efficiency of the photoisomerization of 6‐4PPs into DewarPPs., The UVA and UVB components of sunlight produce three main classes of bipyrimidine DNA photolesions. The UVA/UVB ratio of sunlight is high in winter and low in summer in the Northern Hemisphere. Since UVB produces (6‐4) photoproducts (6‐4PPs) and UVA converts them into Dewar valence isomers (DewarPPs) through photoisomerization, it is expected that there may be seasonal differences in the photoisomerization of 6‐4PPs. Indeed, photoisomerization is more efficient in winter than in late summer after sunlight irradiation, demonstrating that seasonal differences in the UVA/UVB ratio influence the efficiency of the photoisomerization of 6‐4PPs into DewarPPs.

Several classes of oxidatively generated DNA damage including oxidized purine and pyrimidine bases, interstrand base crosslinks and DNA-protein crosslinks have been previously shown to be generated in both isolated DNA and cellular DNA upon exposure to either 266-nm laser irradiation or one-electron oxidants. In this study, we provide evidence that biphotonic ionization of guanine bases by UVC laser irradiation of double-stranded deoxyoligonucleotides in aerated aqueous solutions induces the formation of interstrand crosslinks (ICLs). This is supported by various experiments including sequencing gel analyses of formed photoproducts and effects of UVC laser intensity on their formation. This constitutes a novel example of the diversity of reactions of guanine radical cation that can be generated by various one-electron oxidants including UVC laser biphotonic ionization, direct effect of ionization radiation and type I photosensitizers. However, the exact structure of the interstrand base adducts that is a challenging analytical issue remains to be further established. Examples of relevant biochemical/structural applications of biphotonic induction of ICLs in DNA samples by high-intensity UVC laser pulses are provided.

Photosensitised biphotonic irradiation of DNA has been rarely addressed, probably due to the difficulties in the experimental design. This is associated with the selection of nucleobases and sensitisers with appropriate absorption spectra and photochemical reactivity, in combination with a laser source emitting intense UVA light of the adequate wavelength. The present paper presents a new strategy involving absorption of a first UVA photon by an adequate sensitiser followed by triplet energy transfer to a pyrimidine (Pyr) derivative and absorption of a second UVA photon by the resulting Pyr triplet excited state. The feasibility of the proposed strategy has been demonstrated using two model reactions: (i) the Norrish-Yang photocyclisation of a tert-butyluracil and (ii) the photohydration of its uracil analogue, lacking the tert-butyl substituent., Financial support by the Spanish Government (O. R-A. for FPU14/05294) and Generalitat Valenciana (PROMETEO/2017/075) is gratefully acknowledged. We also thank Dr Lhiaubet-Vallet for her help with the UPLC-MS/MS experiments.

This rebuttal letter is aimed at refuting the poor and false arguments elaborated by Chatgilialoglu (preceding article) in his response to the position article (Cadet et al. Free Radic Res ...

Breast cancer is the second leading cause of death among women; early detection has been shown to reduce morbidity and mortality risk. Nurse practitioners' roles are to screen patients for early detection to provide safe care. This article compares the evidence-based screening guidelines for breast cancer.

International audience; The cyclobutane pyrimidine dimer (CPD) is a main mutagenic photolesion in DNA produced by UVR. We previously studied the wavelength-dependent kinetics of mutation induction efficiency using monochromatic UVR sources and transgenic mice developed for mutation assay and established the action spectra of UVR mutagenicity in the mouse epidermis and dermis. Here, we further established the action spectra of CPD and pyrimidine(6-4)pyrimidone photoproduct formation in the same tissues and in naked DNA using the same sources and mouse strain. Quantitative ELISA helped us estimate the photolesion formation efficiencies on a molecule-per-nucleotide basis. Using these action spectra, we confirmed that the UVR mutation mostly depends on CPD formation. Moreover, the mutagenicity of a CPD molecule (CPD mutagenicity) was found to vary by wavelength, peaking at approximately 313 nm in both the epidermis and dermis with similar wavelength-dependent patterns. Thus, the CPD formation efficiency is a main determinant of UVR mutagenicity in mouse skin, whereas a wavelength-dependent variation in the qualitative characteristics of CPD molecules also affects the mutagenic consequences of UVR insults. In addition, the CPD mutagenicity was always higher in the epidermis than in the dermis, suggesting different cellular responses to UVR between the two tissues irrespective of the wavelength.

Chronic insomnia is the most common sleep disorder. Improper or delayed diagnosis can lead to serious health problems. Early accurate assessment is essential to guide and provide safe treatment. This article reviews assessment and management of insomnia in the primary care setting.

Photosensitization reactions have been demonstrated to be largely responsible for the deleterious biological effects of UV and visible radiation, as well as for the curative actions of photomedicine. A large number of endogenous and exogenous photosensitizers, biological targets and mechanisms have been reported in the past few decades. Evolving from the original definitions of the type I and type II photosensitized oxidations, we now provide physicochemical frameworks, classifications and key examples of these mechanisms in order to organize, interpret and understand the vast information available in the literature and the new reports, which are in vigorous growth. This review surveys in an extended manner all identified photosensitization mechanisms of the major biomolecule groups such as nucleic acids, proteins, lipids bridging the gap with the subsequent biological processes. Also described are the effects of photosensitization in cells in which UVA and UVB irradiation triggers enzyme activation with the subsequent delayed generation of superoxide anion radical and nitric oxide. Definitions of photosensitized reactions are identified in biomolecules with key insights into cells and tissues.

Occupational health nurses need to understand tests for COVID-19 infection and antibodies, how to interpret results, and where to find credible information and resources.

In this issue, Yamano et al. provide further evidence that germicidal 222-nm far UV light has no immediate and delayed harmful effects on the skin and ocular tissue of rats. The safety of 222-nm krypton-chlorine excimer lamps, highlighted in the commentary article, has already received relevant applications in the treatment of surgical site infections and in the control of airborne and foodborne pathogens.

A 76-year-old female patient presented to the emergency department with substernal chest pain and dyspnea symptoms. She reported that the symptoms started 2 days earlier. These symptoms can arise from both cardiac and noncardiac conditions. It is difficult to ascribe chest pain and dyspnea symptoms to a single cause. Recognizing these symptoms is critical for inpatient cardiac and primary care nurse practitioners to choose the correct diagnosis and facilitate more effective treatment planning.

Selective C–H oxidation is thought to be a highly suitable strategy for building synthetic blocks and generating bioactive compounds. Noncovalent DNA catalysis for C–H bond cleavage is studied for the first time in order to delineate the so-called ‘oxidation enhancement effect’ on oxidatively generated damage in DNA duplex structures. Herein, DFT methods have been used to gain insight into the reactivity of the 5-hydroxy-6-peroxyl-5,6-dihydrothymine radical using ten single-stranded and duplex DNA models. Reliable M06-2X/6-31+G(d,p) calculations indicate that hydrogen bonding between the complementary base pairs significantly enhances the reactivity of the thymine peroxyl radical in duplex DNA models towards the C1′–H1′ bond. An excellent linear relationship of the reaction activation barrier vs. the difference between the bond dissociation free energies (BDFE) of the C–H and O–H bonds is observed. With the noted role of charge transfer from LPO4′ on 2-deoxyribose to its adjacent C1′–H1′ anti-bonding orbital, a hyperconjugation effect is proposed to explain the reason why the barrier heights are close to each other for the studied duplex DNA models. The difference in the reactivity of the thymine peroxyl radical in the duplex and related single-strand DNA models is rationalized in terms of the preparatory energy and the optimal σC1′–H1′ and oxyl-p based π*-orbital interactions.

Excessive alcohol intake, e.g., binge drinking, is a serious and mounting public health problem in the United States and throughout the world. Hence the need for novel insights into the underlying neurobiology that may help improve prevention and therapeutic strategies. Therefore, our group employed a darkness-induced alcohol intake protocol to define the reward deficiency domains of alcohol and other substance use disorders in terms of reward pathways’ reduced dopamine signaling and its restoration via specifically-designed therapeutic compounds. It has been determined that KCNK13 and RASGRF2 genes, respectively, code for potassium two pore domain channel subfamily K member 13 and Ras-specific guanine nucleotide-releasing factor 2, and both genes have important dopamine-related functions pertaining to alcohol binge drinking. We present a hypothesis that identification of KCNK13 and RASGRF2 genes’ risk polymorphism, coupled with genetic addiction risk score (GARS)-guided precision pro-dopamine regulation, will mitigate binge alcohol drinking. Accordingly, we review published reports on the benefits of this unique approach and provide data on favorable outcomes for both binge-drinking animals and drunk drivers, including reductions in alcohol intake and prevention of relapse to drinking behavior. Since driving under the influence of alcohol often leads to incarceration rather than rehabilitation, there is converging evidence to support the utilization of GARS with or without KCNK13 and RASGRF2 risk polymorphism in the legal arena, whereby the argument that “determinism” overrides the “free will” account may be a plausible defense strategy. Obviously, this type of research is tantamount to helping resolve a major problem related to polydrug abuse.

Type 2 diabetes mellitus (T2DM) is an endocrine and metabolic disorder that requires ongoing medical management. If T2DM is not adequately assessed and managed, a wide spectrum of clinical manifestations and complications may occur. This article provides clinical guidance to NPs on the management of T2DM in primary care settings.

This is a case study describing a 48-year-old woman complaining of unilateral lower leg edema and dyspnea. Understanding the complexities of these symptoms can help the nurse practitioner to make timely decisions to save a life.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by inflammation of organs systems in the body. Active SLE can put a patient at risk for life-threatening complications such as lupus nephritis (LN), an inflammation of the kidneys that can cause permanent, irreversible organ damage. LN can mimic other illnesses, and medical management may be challenging. The purpose of this article is to aid nurse practitioners in identifying and managing LN as a complication of SLE to provide safe and quality care to patients.