Nonenzymatic conversion of ADP-ribosylated arginines to ornithine alters the biological activities of human neutrophil peptide-1.

Activated neutrophils, recruited to the airway of diseased lung, release human neutrophil peptides (HNP1-4) that are cytotoxic to airway cells as well as microbes. Airway epithelial cells express arginine-specific ADP ribosyltransferase (ART)-1, a GPI-anchored ART that transfers ADP-ribose from NAD to arginines 14 and 24 of HNP-1. We previously reported that ADP-ribosyl-arginine is converted nonenzymatically to ornithine and that ADP-ribosylated HNP-1 and ADP-ribosyl-HNP-(ornithine) were isolated from bronchoalveolar lavage fluid of a patient with idiopathic pulmonary fibrosis, indicating that these reactions occur in vivo. To determine effects of HNP-ornithine on the airway, three analogs of HNP-1, HNP-(R14orn), HNP-(R24orn), and HNP-(R14,24orn), were tested for their activity against Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus; their cytotoxic effects on A549, NCI-H441, small airway epithelial-like cells, and normal human lung fibroblasts; and their ability to stimulate IL-8 and TGF-ß1 release from A549 cells, and to serve as ART1 substrates. HNP and the three analogs had similar effects on IL-8 and TGF-ß1 release from A549 cells and were all cytotoxic for small airway epithelial cells, NCI-H441, and normal human lung fibroblasts. HNP-(R14,24orn), when compared with HNP-1 and HNP-1 with a single ornithine substitution for arginine 14 or 24, exhibited reduced cytotoxicity, but it enhanced proliferation of A549 cells and had antibacterial activity. Thus, arginines 14 and 24, which can be ADP ribosylated by ART1, are critical to the regulation of the cytotoxic and antibacterial effects of HNP-1. The HNP analog, HNP-(R14,24orn), lacks the epithelial cell cytotoxicity of HNP-1, but partially retains its antibacterial activity and thus may have clinical applications in airway disease.

Supporting nurse manager certification.

Professional certification is desirable for nursing staff and leaders to demonstrate high levels of knowledge and expertise. Nurse managers can be role models for staff by attaining certification. The organization highlighted in this article developed a process that included an in-house nurse manager certification review course resulting in increased certification rates from 33% to 50% for nurse managers in a 14-month period.

Population and hospital-level COVID-19 measures are associated with increased risk of hospital-onset COVID-19.

A review of hospital-onset COVID-19 cases revealed 8 definite, 106 probable, and 46 possible cases. Correlations between hospital-onset cases and both HCW and inpatient cases were noted in 2021. Rises in community measures were associated with rises in hospital-onset cases. Measures of community COVID-19 activity might predict hospital-onset cases.

A severe acute respiratory coronavirus virus 2 (SARS-CoV-2) nosocomial cluster with inter-facility spread: Lessons learned.

BACKGROUND: Despite infection control guidance, sporadic nosocomial coronavirus disease 2019 (COVID-19) outbreaks occur. We describe a complex severe acute respiratory coronavirus virus 2 (SARS-CoV-2) cluster with interfacility spread during the SARS-CoV-2 δ (delta) pandemic surge in the Midwest. SETTING: This study was conducted in (1) a hematology-oncology ward in a regional academic medical center and (2) a geographically distant acute rehabilitation hospital. METHODS: We conducted contact tracing for each COVID-19 case to identify healthcare exposures within 14 days prior to diagnosis. Liberal testing was performed for asymptomatic carriage for patients and staff. Whole-genome sequencing was conducted for all available clinical isolates from patients and healthcare workers (HCWs) to identify transmission clusters. RESULTS: In the immunosuppressed ward, 19 cases (4 patients, 15 HCWs) shared a genetically related SARS-CoV-2 isolate. Of these 4 patients, 3 died in the hospital or within 1 week of discharge. The suspected index case was a patient with new dyspnea, diagnosed during preprocedure screening. In the rehabilitation hospital, 20 cases (5 patients and 15 HCWs) positive for COVID-19, of whom 2 patients and 3 HCWs had an isolate genetically related to the above cluster. The suspected index case was a patient from the immune suppressed ward whose positive status was not detected at admission to the rehabilitation facility. Our response to this cluster included the following interventions in both settings: restricting visitors, restricting learners, restricting overflow admissions, enforcing strict compliance with escalated PPE, access to on-site free and frequent testing for staff, and testing all patients prior to hospital discharge and transfer to other facilities. CONCLUSIONS: Stringent infection control measures can prevent nosocomial COVID-19 transmission in healthcare facilities with high-risk patients during pandemic surges. These interventions were successful in ending these outbreaks.

ADP-ribosylation of human defensin HNP-1 results in the replacement of the modified arginine with the noncoded amino acid ornithine.

Defensins (e.g., human neutrophil peptides, or HNPs) contribute to innate immunity through diverse actions, including microbial killing; high concentrations are present in the lung in response to inflammation. Arginines are critical for HNP activity, which is decreased by their replacement with ornithine. ADP-ribosyltransferases (ARTs) catalyze transfer of ADP-ribose from NAD to an acceptor arginine in a protein substrate, whereas ADP-ribosylarginine hydrolases release ADP-ribose. ART1 on the surface of airway epithelial cells ADP-ribosylated HNP-1 specifically on arginines 14 and 24, with ADP-ribosylation altering biological activity. Di- and mono-ADP-ribosylated HNP-1 were isolated from bronchoalveolar lavage fluid (BALF) of patients with asthma and idiopathic pulmonary fibrosis (IPF), suggesting a role for ADP-ribosylation in disease. In the present study, we observed that ART1-catalyzed ADP-ribosylation of HNP-1 in vitro generated a product with ADP-ribose on arginine 24, and ornithine replacing arginine at position 14. We hypothesized that ADP-ribosylarginine is susceptible to a nonenzymatic hydrolytic reaction yielding ornithine. On incubation of di- or mono-ADP-ribosyl-HNP-1 at 37 degrees C, ADP-ribosylarginine was partially replaced by ornithine, whereas ornithine was not detected by amino acid analysis and mass spectrometry of unmodified HNP-1 incubated under the same conditions. Further, ornithine was produced from the model compound, ADP-ribosylarginine. BALF from an IPF patient contained ADP-ribosyl-HNP-ornithine as well as mono- and di-ADP-ribosylated HNP-1, consistent with in vivo conversion of arginine to ornithine. Targeted ADP-ribosylation of specific arginines by transferases, resulting in their replacement with ornithine, is an alternative pathway for regulation of protein function through posttranslational modification.

Reducing specimen identification errors.

In 2006, the University of Wisconsin Hospital and Clinics identified that the number of specimen identification errors each month was much greater than desired and represented a significant patient safety issue. A collaborative performance improvement approach between nursing and the laboratory was undertaken for the inpatient, ambulatory, and surgical services areas, with the focus on creation of a just culture. Between 2007 and 2011, interventions were successful in significantly reducing the number of errors by 85%.

Improving inpatient pneumococcal and influenza vaccination rates.

Since 2004, pharmacists at the University of Wisconsin Hospital and Clinics have screened all adult inpatients for pneumococcal and influenza vaccination. Rates of screening patients improved to nearly 100% between 2004 and 2009, but the rate of actual administration of the vaccines hovered around 45%. A review of the process identified failure modes. This prompted a collaborative effort between pharmacy and nursing for improvement that focused on ensuring that the ordered vaccinations were actually administered. The rates of administration improved from approximately 45% in June 2009 to approximately 78% by mid-2010.

COVID-19 in Health Care Personnel: Significance of Health Care Role, Contact History, and Symptoms in Those Who Test Positive for SARS-CoV-2 Infection.

OBJECTIVE: To identify significant factors that help predict whether health care personnel (HCP) will test positive for severe acute respiratory coronavirus 2 (SARS-CoV-2). PATIENTS AND METHODS: We conducted a prospective cohort study among 7015 symptomatic HCP from March 25, 2020, through November 11, 2020. We analyzed the associations between health care role, contact history, symptoms, and a positive nasopharyngeal swab SARS-CoV-2 polymerase chain reaction test results, using univariate and multivariable modelling. RESULTS: Of the symptomatic HCP, 624 (8.9%) were positive over the study period. On multivariable analysis, having a health care role other than physician or advanced practice provider, contact with family or community member with known or suspected coronavirus disease 2019 (COVID-19), and seven individual symptoms (cough, anosmia, ageusia, fever, myalgia, chills, and headache) were significantly associated with higher adjusted odds ratios for testing positive for SARS-CoV-2. For each increase in symptom number, the odds of testing positive nearly doubled (odds ratio, 1.93; 95% CI, 1.82 to 2.07, P<.001). CONCLUSION: Symptomatic HCP have higher adjusted odds of testing positive for SARS-CoV-2 based on three distinct factors: (1) nonphysician/advanced practice provider role, (2) contact with a family or community member with suspected or known COVID-19, and (3) specific symptoms and symptom number. Differences among health care roles, which persisted after controlling for contacts, may reflect the influence of social determinants. Contacts with COVID-19-positive patients and/or HCP were not associated with higher odds of testing positive, supporting current infection control efforts. Targeted symptom and contact questionnaires may streamline symptomatic HCP testing for COVID-19.

Barriers and facilitators to influenza-like illness absenteeism among healthcare workers in a tertiary-care healthcare system, 2017-2018 influenza season.

OBJECTIVE: Influenza can be introduced and propagated in healthcare settings by healthcare workers (HCWs) working while ill with influenza. However, reasons driving this behavior are unclear. In this study, we examined barriers to and facilitators of absenteeism during the influenza season. DESIGN: Cross-sectional mixed methods study. SETTING: Ambulatory and inpatient settings in a large, tertiary-care healthcare system. METHODS: An anonymous electronic survey was sent to HCWs between June 11 and July 13, 2018, asking participants to self-report influenza-like illness (ie, ILI symptoms of fever, chills, cough, or sore throat) during the 2017-2018 influenza season. We conducted a logistical regression analysis to identify factors associated with absenteeism. RESULTS: Of 14,250 HCWs, 17% responded to the survey. Although 1,180 respondents (51%) reported symptoms of ILI, 575 (43%) did not stay home while ill. The most commonly perceived barriers to ILI absenteeism included being understaffed (odds ratio [OR], 1.78; P = .04), unable to find a replacement for work (OR, 2.26; P = .03), desiring not to use time off (OR, 2.25; P = .003), and paid by the hour or unable to afford being absent (OR, 2.05; P = .02). Common perceived facilitators of absenteeism included support from coworkers and management, clearer policy, better sick days availability, and lower perceived threat of disciplinary action. CONCLUSIONS: Reporting to work with ILI symptoms is common among HCWs. Most barriers and facilitators are related to systems. Addressing system factors, such as policies regarding sick days and sick leave and ensuring adequate backup staffing, is likely to facilitate absenteeism among ill HCWs.

ARH1 in Health and Disease.

Arginine-specific mono-adenosine diphosphate (ADP)-ribosylation is a nicotinamide adenine dinucleotide (NAD)+-dependent, reversible post-translational modification involving the transfer of an ADP-ribose from NAD+ by bacterial toxins and eukaryotic ADP-ribosyltransferases (ARTs) to arginine on an acceptor protein or peptide. ADP-ribosylarginine hydrolase 1 (ARH1) catalyzes the cleavage of the ADP-ribose-arginine bond, regenerating (arginine)protein. Arginine-specific mono-ADP-ribosylation catalyzed by bacterial toxins was first identified as a mechanism of disease pathogenesis. Cholera toxin ADP-ribosylates and activates the α subunit of Gαs, a guanine nucleotide-binding protein that stimulates adenylyl cyclase activity, increasing cyclic adenosine monophosphate (cAMP), and resulting in fluid and electrolyte loss. Arginine-specific mono-ADP-ribosylation in mammalian cells has potential roles in membrane repair, immunity, and cancer. In mammalian tissues, ARH1 is a cytosolic protein that is ubiquitously expressed. ARH1 deficiency increased tumorigenesis in a gender-specific manner. In the myocardium, in response to cellular injury, an arginine-specific mono-ADP-ribosylation cycle, involving ART1 and ARH1, regulated the level and cellular distribution of ADP-ribosylated tripartite motif-containing protein 72 (TRIM72). Confirmed substrates of ARH1 in vivo are Gαs and TRIM72, however, more than a thousand proteins, ADP-ribosylated on arginine, have been identified by proteomic analysis. This review summarizes the current understanding of the properties of ARH1, e.g., bacterial toxin action, myocardial membrane repair following injury, and tumorigenesis.

Utility of Repeat Nasopharyngeal SARS-CoV-2 RT-PCR Testing and Refinement of Diagnostic Stewardship Strategies at a Tertiary Care Academic Center in a Low-Prevalence Area of the United States.

BACKGROUND: Multiple factors have led to an extremely high volume of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction (RT-PCR) testing. Concerns exist about sensitivity and false-negative SARS-CoV-2 RT-PCR testing results. We describe a retrospective observational study examining the utility of repeat nasopharyngeal (NP) SARS-CoV-2 RT-PCR testing at an academic center in a low-prevalence setting. METHODS: All patients within our health system with >1 NP SARS-CoV-2 RT-PCR test result were included. SARS-CoV-2 RT-PCR testing was performed according to 1 of 4 validated assays. Key clinical and demographic data were collected, including whether the patient was inpatient or outpatient at time of the test and whether the test was performed as part of a person under investigation (PUI) for possible coronavirus disease 2019 or for asymptomatic screening. RESULTS: A total of 660 patients had >1 NP SARS-CoV-2 PCR test performed. The initial test was negative in 638. There were only 6 negative-to-positive conversions (0.9%). All 6 were outpatients undergoing a PUI workup 5-17 days after an initial negative result. In >260 inpatients with repeat testing, we found no instances of negative-to-positive conversion including those undergoing PUI or asymptomatic evaluation. CONCLUSIONS: In a low-prevalence area, repeat inpatient testing after an initial negative result, using a highly analytically sensitive SARS-CoV-2 RT-PCR, failed to demonstrate negative-to-positive conversion. The clinical sensitivity of NP RT-PCR testing may be higher than previously believed. These results have helped shape diagnostic stewardship guidelines, in particular guidance to decrease repeated testing in the inpatient setting to optimize test utilization and preserve resources.

The ARH and Macrodomain Families of α-ADP-ribose-acceptor Hydrolases Catalyze α-NAD+ Hydrolysis.

ADP-ribosyltransferases transfer ADP-ribose from ß-NAD+ to acceptors; ADP-ribosylated acceptors are cleaved by ADP-ribosyl-acceptor hydrolases (ARHs) and proteins containing ADP-ribose-binding modules termed macrodomains. On the basis of the ADP-ribosyl-arginine hydrolase 1 (ARH1) stereospecific hydrolysis of α-ADP-ribosyl-arginine and the hypothesis that α-NAD+ is generated as a side product of ß-NAD+/ NADH metabolism, we proposed that α-NAD+ was a substrate of ARHs and macrodomain proteins. Here, we report that ARH1, ARH3, and macrodomain proteins (i.e., MacroD1, MacroD2, C6orf130 (TARG1), Af1521, hydrolyzed α-NAD+ but not ß-NAD+. ARH3 had the highest α-NADase specific activity. The ARH and macrodomain protein families, in stereospecific reactions, cleave ADP-ribose linkages to N- or O- containing functional groups; anomerization of α- to ß-forms (e.g., α-ADP-ribosyl-arginine to ß-ADP-ribose- (arginine) protein) may explain partial hydrolysis of ADP-ribosylated acceptors with an increase in content of ADP-ribosylated substrates. Af1521 and ARH3 crystal structures with bound ADP-ribose revealed similar ADP-ribose-binding pockets with the catalytic residues of the ARH and macrodomain protein families in the N-terminal helix and loop. Although the biological roles of the ARHs and macrodomain proteins differ, they share enzymatic and structural properties that may regulate metabolites such as α-NAD+.

PARP1 inhibition alleviates injury in ARH3-deficient mice and human cells.

Poly(ADP-ribosyl)ation refers to the covalent attachment of ADP-ribose to protein, generating branched, long chains of ADP-ribose moieties, known as poly(ADP-ribose) (PAR). Poly(ADP-ribose) polymerase 1 (PARP1) is the main polymerase and acceptor of PAR in response to DNA damage. Excessive intracellular PAR accumulation due to PARP1 activation leads cell death in a pathway known as parthanatos. PAR degradation is mainly controlled by poly(ADP-ribose) glycohydrolase (PARG) and ADP-ribose-acceptor hydrolase 3 (ARH3). Our previous results demonstrated that ARH3 confers protection against hydrogen peroxide (H2O2) exposure, by lowering cytosolic and nuclear PAR levels and preventing apoptosis-inducing factor (AIF) nuclear translocation. We identified a family with an ARH3 gene mutation that resulted in a truncated, inactive protein. The 8-year-old proband exhibited a progressive neurodegeneration phenotype. In addition, parthanatos was observed in neurons of the patient's deceased sibling, and an older sibling exhibited a mild behavioral phenotype. Consistent with the previous findings, the patient's fibroblasts and ARH3-deficient mice were more sensitive, respectively, to H2O2 stress and cerebral ischemia/reperfusion-induced PAR accumulation and cell death. Further, PARP1 inhibition alleviated cell death and injury resulting from oxidative stress and ischemia/reperfusion. PARP1 inhibitors may attenuate the progression of neurodegeneration in affected patients with ARH3 deficiency.

Mono-ADP-Ribosylation Catalyzed by Arginine-Specific ADP-Ribosyltransferases.

Methods are described for determination of arginine-specific mono-ADP-ribosyltransferase activity of purified proteins and intact cells by monitoring the transfer of ADP-ribose from NAD+ to a model substrate, e.g., arginine, agmatine, and peptide (human neutrophil peptide-1 [HNP1]), and for the nonenzymatic hydrolysis of ADP-ribose-arginine to ornithine, a noncoded amino acid. In addition, preparation of purified ADP-ribosylarginine is included as a control substrate for ADP-ribosylation reactions.

What do visitors know and how do they feel about contact precautions?

Patients with Clostridium difficile infection (CDI) are placed in contact precautions. We surveyed 31 visitors of CDI patients to understand their compliance, knowledge, and perceptions of contact precautions. Although most visitors knew where to find the required personal protective equipment, only 42% were fully compliant with gown and gloves. Family members accounted for 90% of visitors, and roughly half of the reasons given for not gowning were related to a lack of perceived risk for family members. Nursing staff are fundamental sources of personal protective equipment (PPE) information for visitors; however, we found variation in staff communication regarding need for visitor PPE use.

Role of a TRIM72 ADP-ribosylation cycle in myocardial injury and membrane repair.

Mono-ADP-ribosylation of an (arginine) protein catalyzed by ADP-ribosyltransferase 1 (ART1) - i.e., transfer of ADP-ribose from NAD to arginine - is reversed by ADP-ribosylarginine hydrolase 1 (ARH1) cleavage of the ADP-ribose-arginine bond. ARH1-deficient mice developed cardiomyopathy with myocardial fibrosis, decreased myocardial function under dobutamine stress, and increased susceptibility to ischemia/reperfusion injury. The membrane repair protein TRIM72 was identified as a substrate for ART1 and ARH1; ADP-ribosylated TRIM72 levels were greater in ARH1-deficient mice following ischemia/reperfusion injury. To understand better the role of TRIM72 and ADP-ribosylation, we used C2C12 myocytes. ARH1 knockdown in C2C12 myocytes increased ADP-ribosylation of TRIM72 and delayed wound healing in a scratch assay. Mutant TRIM72 (R207K, R260K) that is not ADP-ribosylated interfered with assembly of TRIM72 repair complexes at a site of laser-induced injury. The regulatory enzymes ART1 and ARH1 and their substrate TRIM72 were found in multiple complexes, which were coimmunoprecipitated from mouse heart lysates. In addition, the mono-ADP-ribosylation inhibitors vitamin K1 and novobiocin inhibited oligomerization of TRIM72, the mechanism by which TRIM72 is recruited to the site of injury. We propose that a mono-ADP-ribosylation cycle involving recruitment of TRIM72 and other regulatory factors to sites of membrane damage is critical for membrane repair and wound healing following myocardial injury.

Barriers and facilitators to Clostridium difficile infection prevention: A nursing perspective.

BACKGROUND: Clostridium difficile infection (CDI) is a critical patient safety issue. Consistent and regular performance of appropriate practices is effective in preventing CDI. Variation in adherence to these practices can impede their effective implementation and weaken CDI prevention. METHODS: Using the Systems Engineering Initiative for Patient Safety (SEIPS) framework we convened a focus group of 10 nurses to identify barriers and facilitators to compliance with a CDI prevention bundle that includes (1) prompt diagnostic testing, (2) empirical isolation for patients with suspected CDI, (3) consistent and appropriate contact isolation, (4) hand hygiene, and (5) disinfection of the patient room and objects in the room. On completion of transcript coding, analyses were performed based on bundle intervention and the work system element of the SEIPS model. RESULTS: A total of 58 excerpts were coded. Work system barriers or facilitators were associated with nearly every bundle intervention. The work system elements raised in over half of the excerpts were task (n = 31) (eg, amount of additional effort required to don and doff gloves and gowns) and organization (n = 30) (eg, recognition by all staff of the severity of CDI). Contact isolation was the most frequently discussed bundle intervention (n = 24). CONCLUSIONS: The SEIPS systems engineering framework is useful to evaluate infection prevention practices for CDI and identify opportunities for improvement. Addressing the work system barriers and facilitators identified in this study is essential to effective implementation of infection prevention interventions, specifically for CDI.

Impact of the cardiac troponin testing algorithm on excessive and inappropriate troponin test requests.

Cardiac troponin (cTn) is a key biomarker for the assessment of myocardial injury, but overutilization of this test has increased workload and costs. We developed and implemented an algorithm to eliminate excessive utilization. Significant reduction was observed after the implementation of the algorithm in total cTnI requests (29.9%; P = .007), requests from outpatient clinics (70.7%; P = .003), and other wards (42.8%; P = .003). Stat requests, the number of third requests, and more than 3 requests per patient were reduced significantly by 42.8% (P = .004), 35.8% (P = .003), and 49.4% (P = .008), respectively. The test and labor costs each were reduced by 29.9% (P = .007 for each). There was no significant change in cTnI orders from emergency and critical care departments. The cTnI testing algorithm reduced unnecessary orders for cTnI tests with no reduction in meeting patients'critical needs. Reduction in unnecessary and inappropriate requests reduces labor and test costs.