Electron Attachment to the Nucleobase Uracil in Diethylene Glycol: The Signature of a Doorway.

The cellular environment plays a significant role in low energy electron-mediated radiation damage to genetic materials. In this study, we have modeled the effect of the bulk medium on electron attachment to nucleobases in diethylene glycol (DEG) using uracil as a test case, in accordance with recent experimental work on the observation of dissociative quasi-free electron attachment to nucleoside via excited anion radical in solution (in DEG). Our EOM-CCSD-based quantum mechanical/molecular mechanical (QM/MM) simulations indicate that the electron scavenging by uracil in DEG is much slower than that observed in the aqueous medium due to its viscosity. This work also establishes that a doorway mechanism exists in uracil microsolvated and bulk solvated with DEG, with the dipole-bound state and solvent-bound state acting as doorway states, respectively.

Perceived risk of infection, ethical challenges and motivational factors among frontline nurses in Covid-19 pandemic: prerequisites and lessons for future pandemic.

BACKGROUND: Infection risk was significant for front-line nurses during the Covid-19 outbreak. The pandemic presented several ethical difficulties and sapped nurses' drive to labor harder for longer periods. This study evaluates registered nurses' perceptions of Covid-19 infection risk, ethical dilemmas, and motivating factors. MATERIALS AND METHODS: During March and April 2022, 400 registered nurses from a newly established tertiary care hospital participated in this cross-sectional exploratory survey. The risk assessment scale, motivation to work scale, and ethical dilemma scale were used to assess the perceived risk of infection, motivational factors and ethical challenges experienced by the nurses. Appropriate descriptive and inferential statistics were applied to compute the results. RESULTS: 76.4% of nurses feared working as a nurse put them at higher risk of infection. Besides the fear of contracting infection, nurses believed they were the source of infection to family members (70.8%) and people around (67.5%). 63.3% of nurses agree that they do not have the right to refuse treatment and every patient has the right to receive optimal care, regardless of age, gender, and medical conditions. Professional obligation to treat patients (72.3%) and sound professional knowledge and experience (83.5%) are important motivating factors to work during the pandemic. Multilinear regression analysis revealed that professional education (95% CI, 3.845 - 0.694, p = 0.005), Covid-19 positive status (95% CI,0.455-2.756, p = 0.006), and post-Covid-19 hospitalization (95% CI, 1.395-6.978, p = 0.003) and duration of hospitalization (95% CI, 0.754-0.058, p = 0.022) are independent predictors of higher perceived risk of infection among nurses. CONCLUSIONS: During the pandemic, nurses were afraid to work and faced personal and family risks of contracting the virus. Despite these challenges, they still feel a strong sense of commitment and dedication to providing the best possible care. Nurse administrators need to create a supportive environment that follows ethical principles and meets the needs of nurses to boost their motivation and encourage them to continue working for longer periods.

Electron Attachment to DNA: The Protective Role of Amino Acids.

We have studied the effect of amino acids on the electron attachment properties of a DNA nucleobase, with cytosine as a model system. The equation of motion coupled cluster theory with an extended basis set has been used to simulate the electron-attached state of the DNA model system. Arginine, alanine, lysine, and glycine are the four amino acids considered to investigate their role in electron attachment to a DNA nucleobase. The electron attachment to cytosine in all the four cytosine-amino acid gas-phase dimer complexes follows a doorway mechanism, where the electron gets transferred from the initial dipole-bound doorway state to the final nucleobase-bound state through the mixing of electronic and nuclear degrees of freedom. When cytosine is bulk-solvated with glycine, the glycine-bound state acts as the doorway state, where the initial electron density is localized on the bulk amino acid and away from the nucleobase, thus leading to the physical shielding of the nucleobase from the incoming electron. At the same time, the presence of amino acids can increase the stability of the nucleobase-bound anionic state, which can suppress the sugar-phosphate bond rupture caused by dissociative electron attachment to DNA.

Shape resonance induced electron attachment to cytosine: The effect of aqueous media.

We have investigated the impact of microsolvation on shape-type resonance states of nucleobases, taking cytosine as a case study. To characterize the resonance position and decay width of the metastable states, we employed the newly developed DLPNO-based EA-EOM-CCSD method in conjunction with the resonance via Padé (RVP) method. Our calculations show that the presence of water molecules causes a redshift in the resonance position and an increase in the lifetime for the three lowest-lying resonance states of cytosine. Furthermore, there are some indications that the lowest resonance state in isolated cytosine may get converted to a bound state in the presence of an aqueous environment. The obtained results are extremely sensitive to the basis set used for the calculations.

The Role of Bioinformatics and Imaging Models in Tumorigenesis and Treatment Response of Brain and Spinal Cord Neoplasm.

This chapter focuses on the division and location of brain deformities such as tumors in magnetic resonance imaging (MRI) through Chan-Vese active contour segmentation. Brain tumor division and identification is a major test in the area of biomedical picture processing. To detect the size and location of the tumor, various techniques are available, but active contour gives accurate knowledge of the region for segmentation. Chan-Vese Active contour method provides independent, robust and more flexible segmentation. In this chapter, firstly we used preprocessing technique in which noise and unused parts of the brain and skull are removed, for this we proposed the skull stripping method. Then, we applied feature extraction to enhance the image intensity and quality, and lastly, used Chan-Vese active contour with a level set image segmentation technique to detect the tumor. The tumor area was calculated after tumor detection.

Numerical Simulation of bio-heat transfer for cryoablation of regularly shaped tumours in liver tissue using multiprobes.

The present study focuses upon pre-operative planning strategy for cryosurgical treatment of multiple regularly shaped tumours inside a three dimensional liver tissue. Numerical simulations provide an optimal framework to predict the number of cryo-probes, their placement, operation time and thermal necrosis to the tumour and surrounding healthy tissues. An efficient cryosurgery process requires keeping the tumour cell under lethal temperature which is between -40 °C to -50 °C. The freezing process of undesired tumour tissues involves phase transition from liquid phase to solid phase, the accurate capturing of transition front and size or location of ice balls generated in the process are the important factors of cryosurgery. In this study, fixed domain heat capacity method has been utilized to take into account the latent heat of phase change in bio-heat transfer equation. The ice balls generated with different number of probes haven been analysed. Numerical simulations have been carried out using standard Finite Element Method with COMSOL 5.5 and results obtained are validated with previous studies.

Methionine sulfoxide reductase B5 plays a key role in preserving seed vigor and longevity in rice (Oryza sativa).

Oxidation of methionine leads to the formation of methionine S-sulfoxide and methionine R-sulfoxide, which can be reverted by two types of methionine sulfoxide reductase (MSR): MSRA and MSRB. Though the role of MSR enzymes has been elucidated in various physiological processes, the regulation and role of MSR in seeds remains poorly understood. In this study, through molecular, biochemical, and genetic studies using seed-specific overexpression and RNAi lines of OsMSRB5 in Oryza sativa, we demonstrate the role of OsMSRB5 in maintaining seed vigor and longevity. We show that an age-induced reduction in the vigor and viability of seeds is correlated with reduced MSR activity and increased methionine sulfoxide (MetSO) formation. OsMSRB5 expression increases during seed maturation and is predominantly localized to the embryo. Further analyses on transgenic lines reveal the role of OsMSRB5 in modulating reactive oxygen species (ROS) homeostasis to preserve seed vigor and longevity. We show that ascorbate peroxidase and PROTEIN l-ISOASPARTYL METHYLTRANSFERASE undergo MetSO modification in seeds that affects their functional competence. OsMSRB5 physically interacts with these proteins and reverts this modification to facilitate their functions and preserve seed vigor and longevity. Our results thus illustrate the role of OsMSRB5 in preserving seed vigor and longevity by modulating ROS homeostasis in seeds.

Results From a National Mixed-Methods Study Exploring Community Health Improvement Implementation: An Opportunity to Strengthen Public Health Systems Through Collective Action.

CONTEXT: There are multiple calls for public health agency role and workforce transformation to increase capacity to orchestrate cross-sectoral partnerships that set and implement strategies addressing the structural and social determinants of health. Mobilizing for Action through Planning and Partnerships (MAPP) may be one tool for collective action to improve population health and equity. However, little is known about the Action Cycle in MAPP and implementation of resulting community health improvement plans. OBJECTIVE: To explore the characteristics of MAPP users who completed the MAPP Action Cycle and factors that facilitated or inhibited implementation activities during this phase. METHODS: We used a sequential participatory mixed-methods design involving 2 phases of data collection. The first data collection phase included a Web-based survey using Qualtrics. The second data collection phase included qualitative key-informant interviews and focus groups. A national public health and health care advisory group informed the evaluation throughout the entire process to ground the process in practice and experience. RESULTS: This study showed that some MAPP participants do not conduct implementation activities as defined by the MAPP Action Cycle and of those who do, implementation activity varies by participant experiences conducting MAPP and accreditation status. The MAPP users who completed 3 or more rounds of MAPP were more likely to align and integrate MAPP within their agencies as well as organize a collaborative implementation process with partners. More resources and skills in planning that facilitate long-range partnerships were noted as key to implementation. CONCLUSIONS: Opportunity remains to improve implementation in MAPP. National leaders should explore and build capacity and infrastructure within public health agencies and with their partners to create a system of readiness and an infrastructure that support implementation over time.

Arabidopsis protein l-ISOASPARTYL METHYLTRANSFERASE repairs isoaspartyl damage to antioxidant enzymes and increases heat and oxidative stress tolerance.

Stressful environments accelerate the formation of isoaspartyl (isoAsp) residues in proteins, which detrimentally affect protein structure and function. The enzyme PROTEIN l-ISOASPARTYL METHYLTRANSFERASE (PIMT) repairs other proteins by reverting deleterious isoAsp residues to functional aspartyl residues. PIMT function previously has been elucidated in seeds, but its role in plant survival under stress conditions remains undefined. Herein, we used molecular, biochemical, and genetic approaches, including protein overexpression and knockdown experiments, in Arabidopsis to investigate the role of PIMTs in plant growth and survival during heat and oxidative stresses. We demonstrate that these stresses increase isoAsp accumulation in plant proteins, that PIMT activity is essential for restricting isoAsp accumulation, and that both PIMT1 and PIMT2 play an important role in this restriction and Arabidopsis growth and survival. Moreover, we show that PIMT improves stress tolerance by facilitating efficient reactive oxygen species (ROS) scavenging by protecting the functionality of antioxidant enzymes from isoAsp-mediated damage during stress. Specifically, biochemical and MS/MS analyses revealed that antioxidant enzymes acquire deleterious isoAsp residues during stress, which adversely affect their catalytic activities, and that PIMT repairs the isoAsp residues and thereby restores antioxidant enzyme function. Collectively, our results suggest that the PIMT-mediated protein repair system is an integral part of the stress-tolerance mechanism in plants, in which PIMTs protect antioxidant enzymes that maintain proper ROS homeostasis against isoAsp-mediated damage in stressful environments.

Electron Attachment to Cytosine: The Role of Water.

We present an EOM-CCSD-based quantum mechanical/molecular mechanical (QM/MM) study on the electron attachment process to solvated cytosine. The electron attachment in the bulk solvated cytosine occurs through a doorway mechanism, where the initial electron is localized on water. The electron is subsequently transferred to cytosine by the mixing of electronic and nuclear degrees of freedom, which occurs on an ultrafast time scale. The bulk water environment stabilizes the cytosine-bound anion by an extensive hydrogen-bond network and drastically enhances the electron transfer rate from that observed in the gas phase. Microhydration studies cannot reproduce the effect of the bulk water environment on the electron attachment process, and one needs to include a large number of water molecules in the calculation to obtain converged results. The predicted adiabatic electron affinity and electron transfer rate obtained from our QM/MM calculations are consistent with the available experimental results.

Ca2+-CBL-CIPK: a modulator system for efficient nutrient acquisition.

Calcium (Ca2+) is a universal second messenger essential for the growth and development of plants in normal and stress situations. In plants, the proteins, CBL (calcineurin B-like) and CIPK (CBL-interacting protein kinase), form one of the important Ca2+ decoding complexes to decipher Ca2+ signals elicited by environmental challenges. Multiple interactors distinguish CBL and CIPK protein family members to form a signaling network for regulated perception and transduction of environmental signals, e.g., signals generated under nutrient stress conditions. Conservation of equilibrium in response to varying soil nutrient status is an important aspect for plant vigor and yield. Signaling processes have been reported to observe nutrient fluctuations as a signal responsible for regulated nutrient transport adaptation. Recent studies have identified downstream targets of CBL-CIPK modules as ion channels or transporters and their association in signaling nutrient disposal including potassium, nitrate, ammonium, magnesium, zinc, boron, and iron. Ca2+-CBL-CIPK pathway modulates ion transporters/channels and hence maintains a homeostasis of several important plant nutrients in the cytosol and sub-cellular compartments. In this article, we summarize recent literature to discuss the role of the Ca2+-CBL-CIPK pathway in cellular osmoregulation and homeostasis on exposure to nutrient excess or deprived soils. This further establishes a link between taking up the nutrient in the roots and its distribution and homeostasis during the generation of signal for the development and survival of plants.

A Rare and Lethal Complication of Oral Warfarin Therapy.

How to cite this article: Mahto SK, Sheoran A, et al. A Rare and Lethal Complication of Oral Warfarin Therapy. Indian J Crit Care Med 2019;23(4):197-198.

Arabidopsis SKP1-like protein13 (ASK13) positively regulates seed germination and seedling growth under abiotic stress.

SKP1 (S-phase kinase-associated protein1) proteins are key members of the SCF (SKP-cullin-F-box protein) E3 ligase complexes that ubiquitinate target proteins and play diverse roles in plant biology. However, in comparison with other members of the SCF complex, knowledge of SKP1-like proteins is very limited in plants. In the present work, we report that Arabidopsis SKP1-like protein13 (ASK13) is differentially regulated in different organs during seed development and germination and is up-regulated in response to abiotic stress. Yeast two-hybrid library screening and subsequent assessment of in vivo interactions through bimolecular fluorescence complementation analysis revealed that ASK13 not only interacts with F-box proteins but also with other proteins that are not components of SCF complexes. Biochemical analysis demonstrated that ASK13 not only exists as a monomer but also as a homo-oligomer or heteromer with other ASK proteins. Functional analysis using ASK13 overexpression and knockdown lines showed that ASK13 positively influences seed germination and seedling growth, particularly under abiotic stress. Taken together, our data strongly suggest that apart from participation to form SCF complexes, ASK13 interacts with several other proteins and is implicated in different cellular processes distinct from protein degradation.

Public Health Employees' Perception of Workplace Environment and Job Satisfaction: The Role of Local Health Departments' Engagement in Accreditation.

OBJECTIVES: To examine the association between local health departments' (LHDs') engagement in accreditation and their staffs' perceptions of workplace environment and the overall satisfaction with their jobs. DESIGN: Data from the 2014 Public Health Workforce Interests and Needs Survey (PH WINS) (local data only) and the 2014 Forces of Change survey were linked using LHDs' unique ID documented by the National Association of County & City Health Officials. The Forces of Change survey assessed LHDs' accreditation status. Local health departments were classified as "formally engaged" in the Public Health Accreditation Board accreditation process if they had achieved accreditation, submitted an application, or submitted a statement of intent. The PH WINS survey measured employees' perception of 3 aspects of workplace environment, including supervisory support, organizational support, and employee engagement. The overall satisfaction was measured using the Job in General Scale (abridged). There are 1884 LHD employees who completed PH WINS and whose agencies responded to the question on the accreditation status of the Forces of Change survey. RESULTS: When compared with employees from LHDs less engaged in accreditation, employees from LHDs that were formally engaged in accreditation gave higher ratings to all 3 aspects of workplace environment and overall job satisfaction. Controlling for employee demographic characteristics and LHD jurisdiction size, the agency's formal engagement in accreditation remained related to a higher score in perceived workplace environment and job satisfaction. After controlling for perceived workplace environment, accreditation status was marginally associated with job satisfaction. CONCLUSION: The findings provide support for previous reports by LHD leaders on the benefits of accreditation related to employee morale and job satisfaction. The results from this study allow us to further catalog the benefits of accreditation in workforce development and identify factors that may moderate the extent of the benefits. Findings from this study show that engagement in public health accreditation is associated with overall job satisfaction. This link may be explained by the hypotheses that meeting accreditation standards could increase staff satisfaction or that having higher job satisfaction could lead to a higher likelihood that a health department would apply for accreditation. Further research to explore this relationship is critical as many health departments are weighing the value of accreditation as they face constrained financial resources.

Dissociation Chemistry of 3-Oxetanone in the Gas Phase.

3-Oxetanone is a strained cyclic molecule which plays an important role in synthetic chemistry. A few studies exist in the literature about the equilibrium properties of this molecule and the dissociation patterns of substituted 3-oxetanones. For the unsubstituted 3-oxetanone, formation of ketene (CH2CO) and formaldehyde (HCHO) was considered to be the major dissociation pathway. In a recent work, pyrolysis products of 3-oxetanone molecule in the gas phase were investigated by Fourier transform infrared spectroscopy and photoionization mass spectrometry. In this study, an additional dissociation channel forming ethylene oxide (c-C2H4O) and carbon monoxide CO was reported. In the present work, gas phase dissociation chemistry of 3-oxetanone was investigated by electronic structure theory, ab initio classical chemical dynamics simulations, and Rice-Ramsperger-Kassel-Marcus (RRKM) rate constant calculations. The barrier height for the ethylene oxide channel was found to be much higher than the ketene pathway. The dynamics simulations were performed at three different total energies, viz., 150, 200, and 300 kcal/mol, and multiple reaction pathways and varying branching ratios observed. A new dissociation channel involving a ring-opened isomer of ethylene oxide was identified in the simulations. This pathway has a lower energy barrier and was dominant in our dynamics simulations.

Rice PROTEIN l-ISOASPARTYL METHYLTRANSFERASE isoforms differentially accumulate during seed maturation to restrict deleterious isoAsp and reactive oxygen species accumulation and are implicated in seed vigor and longevity.

PROTEIN l-ISOASPARTYL O-METHYLTRANSFERASE (PIMT) is a protein-repairing enzyme involved in seed vigor and longevity. However, the regulation of PIMT isoforms during seed development and the mechanism of PIMT-mediated improvement of seed vigor and longevity are largely unknown. In this study in rice (Oryza sativa), we demonstrate the dynamics and correlation of isoaspartyl (isoAsp)-repairing demands and PIMT activity, and their implications, during seed development, germination and aging, through biochemical, molecular and genetic studies. Molecular and biochemical analyses revealed that rice possesses various biochemically active and inactive PIMT isoforms. Transcript and western blot analyses clearly showed the seed development stage and tissue-specific accumulation of active isoforms. Immunolocalization studies revealed distinct isoform expression in embryo and aleurone layers. Further analyses of transgenic lines for each OsPIMT isoform revealed a clear role in the restriction of deleterious isoAsp and age-induced reactive oxygen species (ROS) accumulation to improve seed vigor and longevity. Collectively, our data suggest that a PIMT-mediated, protein repair mechanism is initiated during seed development in rice, with each isoform playing a distinct, yet coordinated, role. Our results also raise the intriguing possibility that PIMT repairs antioxidative enzymes and proteins which restrict ROS accumulation, lipid peroxidation, etc. in seed, particularly during aging, thus contributing to seed vigor and longevity.

PROTEIN L-ISOASPARTYL METHYLTRANSFERASE2 is differentially expressed in chickpea and enhances seed vigor and longevity by reducing abnormal isoaspartyl accumulation predominantly in seed nuclear proteins.

PROTEIN l-ISOASPARTYL METHYLTRANSFERASE (PIMT) is a widely distributed protein-repairing enzyme that catalyzes the conversion of abnormal l-isoaspartyl residues in spontaneously damaged proteins to normal aspartyl residues. This enzyme is encoded by two divergent genes (PIMT1 and PIMT2) in plants, unlike many other organisms. While the biological role of PIMT1 has been elucidated, the role and significance of the PIMT2 gene in plants is not well defined. Here, we isolated the PIMT2 gene (CaPIMT2) from chickpea (Cicer arietinum), which exhibits a significant increase in isoaspartyl residues in seed proteins coupled with reduced germination vigor under artificial aging conditions. The CaPIMT2 gene is found to be highly divergent and encodes two possible isoforms (CaPIMT2 and CaPIMT2') differing by two amino acids in the region I catalytic domain through alternative splicing. Unlike CaPIMT1, both isoforms possess a unique 56-amino acid amino terminus and exhibit similar yet distinct enzymatic properties. Expression analysis revealed that CaPIMT2 is differentially regulated by stresses and abscisic acid. Confocal visualization of stably expressed green fluorescent protein-fused PIMT proteins and cell fractionation-immunoblot analysis revealed that apart from the plasma membrane, both CaPIMT2 isoforms localize predominantly in the nucleus, while CaPIMT1 localizes in the cytosol. Remarkably, CaPIMT2 enhances seed vigor and longevity by repairing abnormal isoaspartyl residues predominantly in nuclear proteins upon seed-specific expression in Arabidopsis (Arabidopsis thaliana), while CaPIMT1 enhances seed vigor and longevity by repairing such abnormal proteins mainly in the cytosolic fraction. Together, our data suggest that CaPIMT2 has most likely evolved through gene duplication, followed by subfunctionalization to specialize in repairing the nuclear proteome.

Creating quality improvement culture in public health agencies.

OBJECTIVES: We conducted case studies of 10 agencies that participated in early quality improvement efforts. METHODS: The agencies participated in a project conducted by the National Association of County and City Health Officials (2007-2008). Case study participants included health directors and quality improvement team leaders and members. We implemented multiple qualitative analysis processes, including cross-case analysis and logic modeling. We categorized agencies according to the extent to which they had developed a quality improvement culture. RESULTS: Agencies were conducting informal quality improvement projects (n = 4), conducting formal quality improvement projects (n = 3), or creating a quality improvement culture (n = 4). Agencies conducting formal quality improvement and creating a quality improvement culture had leadership support for quality improvement, participated in national quality improvement initiatives, had a greater number of staff trained in quality improvement and quality improvement teams that met regularly with decision-making authority. Agencies conducting informal quality improvement were likely to report that accreditation is the major driver for quality improvement work. Agencies creating a quality improvement culture were more likely to have a history of evidence-based decision-making and use quality improvement to address emerging issues. CONCLUSIONS: Our findings support previous research and add the roles of national public health accreditation and emerging issues as factors in agencies' ability to create and sustain a quality improvement culture.

Sustaining a quality improvement culture in local health departments applying for accreditation.

CONTEXT: This article focuses on local health departments (LHDs) that are advanced in accreditation and quality improvement (QI) efforts and the barriers and facilitators associated with sustaining improvements and building an organizational culture of QI. OBJECTIVE: To understand the barriers and facilitators associated with building and sustaining progress toward a QI culture in LHDs. DESIGN: Quantitative data from a self-reporting survey and qualitative data from telephone interviews. SETTING: Twenty-two LHDs across the United States responded to the survey. Ten of the 22 LHD respondents participated in telephone interviews. PARTICIPANTS: QI lead staff at LHDs that are advanced in accreditation preparation and QI. MAIN OUTCOME MEASURES: Self-reported LHD survey ratings against indicators for a QI culture, and the identified barriers and facilitators around sustaining QI initiatives. RESULTS: Of the 6 domains of a QI culture measured in the survey, the percentages of respondents that scored themselves highly to at least 1 indicator in each domain are as follows: leadership commitment (100%); employee empowerment (100%); teamwork and collaboration (100%); continuous process improvement (86%); customer focus (72%); and QI infrastructure (64%). Qualitative data from 10 telephone interviews revealed that key barriers to sustaining progress around QI included staff turnover, budget cuts, and major crises or events that arise as priority. Key facilitators included leadership commitment, accreditation, and dedication of resources and staff time to QI. CONCLUSIONS: When engaging in QI, LHDs should consider investing efforts in gaining leadership support and dedicating staff time early in the QI journey to ensure that QI efforts and initiatives are sustained. Local health departments interested in developing a QI culture should also consider pursuing accreditation, as it provides a structured framework for continuous improvement. They should also actively develop QI knowledge and skills among all staff members to minimize the negative impact of staff turnover.