Modulation of Viral Programmed Ribosomal Frameshifting and Stop Codon Readthrough by the Host Restriction Factor Shiftless.

The product of the interferon-stimulated gene C19orf66, Shiftless (SHFL), restricts human immunodeficiency virus replication through downregulation of the efficiency of the viral gag/pol frameshifting signal. In this study, we demonstrate that bacterially expressed, purified SHFL can decrease the efficiency of programmed ribosomal frameshifting in vitro at a variety of sites, including the RNA pseudoknot-dependent signals of the coronaviruses IBV, SARS-CoV and SARS-CoV-2, and the protein-dependent stimulators of the cardioviruses EMCV and TMEV. SHFL also reduced the efficiency of stop-codon readthrough at the murine leukemia virus gag/pol signal. Using size-exclusion chromatography, we confirm the binding of the purified protein to mammalian ribosomes in vitro. Finally, through electrophoretic mobility shift assays and mutational analysis, we show that expressed SHFL has strong RNA binding activity that is necessary for full activity in the inhibition of frameshifting, but shows no clear specificity for stimulatory RNA structures.

Increasing your decision-making role in ethical situations.

Critical care nurses are increasingly involved in situations of ethical conflict; yet, they are often left out of consequential decision making. This article discusses ways critical care nurses can become more deeply involved in actual decision making in ethical situations.

Advance directives: a program design for home healthcare.

Home care agencies receiving Medicare and Medicaid reimbursement are now required to adhere to the regulations of the Patient Self-Determination Act of 1990. These regulations require all agencies to inform clients older than 18 years of their right to plan for their care in advance, and to provide clients with the agency's written policy respecting this right. It also requires that agencies educate their staff about the new provisions. This report presents a program designed to orient all new and continuing home care staff members with the requirements to ensure compliance with this important directive.

The ethical quandaries of acute care nursing practice.

This study explored the perceptions of nurses employed in acute care nursing regarding the ethical quandaries in which they find themselves involved on a recurrent basis. Sixty-five female nurses volunteered to participate in the study. Data were collected over a 2-year period at four institutions. Qualitative methods were used to collect and analyze the data. Three categories were derived from the situational conditions described. These were exploitation, ie, nurses' concern with the inhumane treatment of seriously ill patients; exclusion, ie, the lack of attention paid to patient wishes in treatment decisions; and anguish, ie, the powerlessness and frustration felt by nurses involved in ethical situations. It was concluded that in an era of escalating, complex dilemmas, nurses are willing and motivated to engage in ethical decision-making situations, particularly when the comfort or rights of their patients are involved. The environmental barriers to this practice, however, are staggering. The barriers identified included lack of support or poorly defined mechanisms of support, time pressures, personal concerns over security, and hierarchic forces within the institution. Nurses' inability to act on behalf of patients or with regard to their individual conscience may be contributing to high turnover rates and the nursing shortage, particularly in those areas with high use of technology.

Ethical practice in acute care nursing: are we there yet?

Ethical practice is a necessary component of nursing in today's complex clinical arena. This paper reviews the current status of ethics teaching in nursing education and the role of nurses in ethical decision making in acute care hospitals.

A program design for preceptor training.

Training clinical preceptors in the subtleties of clinical teaching is essential to the success of precepted orientations. This paper presents a program design for the preparation of these preceptors. Emphasis is on the assumptions underlying the program, program content, and evaluation.

Methodological pluralism in clinical nursing research.

Clinical nursing research can benefit from an approach that blends discovery oriented qualitative methods with the objective, numerically based quantitative methods. This paper describes current approaches to clinical research in either the quantitative or qualitative paradigm. The strengths and weaknesses of each of these approaches are discussed. A rationale for methodological pluralism--the blending of the two methods--to understand clinical phenomena is presented.

Access and acceptance in clinical nursing research.

As clinical research comes to the forefront of nursing research endeavors, the issues of access to clinical sites and acceptance of both the researcher and the project become increasing important. This paper discusses these issues within the framework of politics and ethics. Emphasis is placed on maintaining the integrity of the research while gaining entry and winning acceptance.

Attacking the nursing shortage from within: the Columbia model.

This paper discusses a three-pronged approach to easing the crises of the nursing shortage from within the profession. Its premise is that it is necessary to develop, test, and evaluate models that have the potential to change the education of students, the reward systems for the nursing profession, and the delivery of nursing services. The initiatives developed to address these concerns are faculty practice, the clinical preceptorship, and the accelerated master's program.

Generation of a PGI2-like activity by deendothelialized rat aorta.

We have tested a platelet aggregation inhibitor in the incubation fluid of deendothelialized fragments of the rat aorta and compared it with that of "intact" fragments. Some of the properties of the aortic inhibitor, and its effects on platelet adhesion to collagen fibrils, on platelet factor-3 (PF-3) availability, and on the activated partial thromboplastin time (APTT) and thrombin time (TT) were also evaluated in comparison with similar effects exerted by PGI2. We found that the incubation fluid of deendothelialized aortic samples contained inhibitor activity comparable with that of "intact" samples. The aortic inhibitor had similar properties to PGI2. The aortic inhibitor and PGI2 slightly inhibited light transmission changes of EDTA-PRP following exposure to collagen. However, scanning electron microscopy showed no appreciable difference in platelet adhesion to collagen fibrils. PGI2 and the aortic inhibitor inhibited Kaolin-induced PF-3 availability, but did not prolong the APTT or TT.

Arachidonic acid causes lysis of human platelets in an artificial medium: protection by plasma.

Addition of 1 or 2 mM of arachidonic acid (AA) to a washed platelet suspension (WPS) resulted in an instantaneous rise of light transmission (LT) in the platelet aggreagameter. The LT curves showed no evidence ofshape change patterns and the recording pen showed no fluctuations. This rise of LT was not affected by the absence of CaCl2, or the presence of PGI2 or ASA. However, LT curves, showing shape change patterns and with pen fluctuations, were obtained when plasma, serum or albumin was included in the test system. These latter form of LT curves were also obtained in WPS samples exposed to lower concentrations of AA. Electron microscopic examination of these samples revealed varying degrees of lysis of every platelet in WPS exposed to 1 mM of AA. Numerous lyzed platelets were also found in samples either exposed to 0.5 mM of AA in the absence of added plasma, serum or albumin, or exposed to 1 mM of AA in the presence of 5% of added plasma or 2.5 mg/ml albumin. The LT curves of these samples showed shape change patterns and pen fluctuations. These results indicate a pitfall of relying on platelet aggregometry alone in the study of certain AA-induced responses of washed platelets.

Increased production of PGI2-like activity by frozen-thawed rat aorta.

The effects of storage conditions, temperature, and time on the ability of the rat thoracic aorta to produce a platelet aggregation inhibitor were investigated. Aortic fragments were incubated in Tris buffer, aliquots of which were then tested for their ability to inhibit ADP-induced human platelet aggregation. The incubation fluid of samples that had been soaked in Tris buffer at 4 degrees C for 24 hours contained no inhibitor activity, whereas the incubation fluid of similar samples that had been kept at 4 degrees C but not soaked in buffer contained comparable inhibitor activity as that of fresh samples. The incubation fluid of samples that had been kept at -20 degrees C or -80 degrees C contained greater inhibitor activity than that of fresh samples, and was maintained in -20 degrees C samples for 7 days, and -80 degrees samples for 28 days. The aortic inhibitor had similar properties as PGI2.