Protein-dependent transition states for ribonucleoprotein assembly

Native folding and splicing by the Saccharomyces cerevisiae mitochondrial bI5 group I intron RNA is facilitated by both the S. cerevisiae CBP2 and Neurospora crassa CYT-18 protein cofactors. Both protein-bI5 RNA complexes splice at similar rates, suggesting that the RNA active site structure is similar in both ribonucleoproteins. In contrast, the two proteins assemble with the bI5 RNA by distinct mechanisms and bind opposing, but partially overlapping, sides of the group I intron catalytic core. Assembly with CBP2 is limited by a slow, unimolecular RNA folding step characterized by a negligible activation enthalpy. We show that assembly with CYT-18 shows four distinctive features. (1) CYT-18 binds stably to the bI5 RNA at the diffusion controlled limit, but assembly to a catalytically active RNA structure is still limited by RNA folding, as visualized directly using time-resolved footprinting. (2) This mechanism of rapid stable protein binding followed by subsequent assembly steps has a distinctive kinetic signature: the apparent ratio of k(off) to k(on), determined in a partitioning experiment, differs from the equilibrium K(d) by a large factor. (3) Assembly with CYT-18 is characterized by a large activation enthalpy, consistent with a rate limiting conformational rearrangement. (4) Because assembly from the kinetically trapped state is faster at elevated temperature, we can identify conditions where CYT-18 accelerates (catalyzes) bI5 RNA folding relative to assembly with CBP2.

Visualizing induced fit in early assembly of the human signal recognition particle

Assembly of almost all ribonucleoprotein complexes involves induced fit in the RNA and, thus, formation of one or more intermediate states. In assembly of the human signal recognition particle (SRP), we show that SRP19 binding to SRP RNA involves obligatory intermediates. An apparent discrepancy exists between the ratio of dissociation and association rate constants, determined in a partitioning experiment, and the equilibrium binding constant; this kinetic signature reflects formation of a stable intermediate in assembly of the ribonucleoprotein complex. Assembly intermediates were observed directly by time-resolved footprinting. SRP19 binds rapidly to SRP RNA to form an initial labile, but structurally specific, encounter complex involving both helices III and IV. Two subsequent steps of structural consolidation yield the native RNA-protein interface. SRP19 binding stabilizes helix IV in the region recognized by SRP54, consistent with protein-protein cooperativity mediated in part by mutual recognition of similar RNA structures. This mechanism illustrates principles general to ribonucleoprotein assembly reactions that rely on recruitment of architectural RNA binding proteins.

Global connections in a changing world: Romanian and U.S. nurses unite

This article describes an international, interdisciplinary, university partnership project to collaborate with health professionals in the city of Cluj-Napoca, Transylvania, Romania, to improve the health status of Romanian workers. Academic and service-based public health nurses from the United States used the model of community competence in outlining the nursing aspect of the project. This model guided the assessment, objectives, collaborative activities, and the outcome evaluation of the project. The dimensions of the model (e.g., commitment, self-other awareness, articulateness, conflict accommodation, management of relations with larger society, and leadership) were used within the context of the political and social environment of the international community.

Evaluation of the effectiveness of a Web-based graduate epidemiology course

An online epidemiology course was developed, implemented, and evaluated for graduate nursing students through the collaborative efforts of nursing faculty and information, education, and instructional design staff of the library at a health sciences university. This epidemiology course is a core curriculum course for graduate nursing students. The course was piloted with 14 students (one student in Romania); the initial online offering ran concurrently with a traditional classroom section. Extensive evaluation data were collected and analyzed to compare the effectiveness of the classroom and distance-learning formats. Areas of evaluation included objective measures, such as midterm and final examination scores and content analysis comparisons, as well as subjective ratings by the students of time commitments, course objectives, technical aspects of the web-based course, areas of satisfaction or dissatisfaction, and self-confidence regarding epidemiology and computer skills. Recommendations for course development, implementation, and evaluation for similar distance-learning courses will be included.

Coping styles of caregivers of children with HIV/AIDS: implications for health professionals

In a study to examine the coping styles and quality of life of non-parental caregivers of children with HIV/AIDS, 25 non-parental caregivers used confrontive coping most often and passive and emotive coping much less often. The two most frequently used coping styles were prayer and efforting to maintain some control over the situation. Quality of life correlations showed that support from family/friends was significantly related to all of the quality of life subscales. Time spent caring for the HIV-positive child was significantly inversely related to all aspects of quality of life. The conclusions drawn from the study were that interventions are needed to help support caregivers of children with HIV/AIDS. Examples of primary, secondary, and tertiary prevention measures for health professionals are discussed.

Caregivers of children with HIV/AIDS: quality of life and coping styles

The purpose of this study was to explore the quality of life and coping styles of caregivers of children with HIV/AIDS and to identify if there were differences between mothers and alternative caregivers in these areas. There were 54 mother-caregivers and 25 alternative caregivers in the study. The alternative caregivers scored significantly higher in each area of quality of life than the mothers, except for physical health. The mothers used passive and emotive coping significantly more than the alternative caregivers. The study concluded that caregivers provide support to children with HIV/AIDS, but they also need physical and emotional support themselves. Nurses must be aware of the importance of providing interventions for these caregivers to improve coping mechanisms, decrease stress, and thereby improve their quality of life.

Evidence for direct interaction of ketamine with alpha 1- and beta 2-adrenoceptors

1. Ketamine has a number of effects that suggest that it may interact with alpha- and beta-adrenoceptors. To date, the experimental evidence for this has been indirect and has been based on physiological studies using competitive blocking agents. In the present study we sought to determine from receptor binding studies whether ketamine binds directly to alpha- and beta-adrenoceptors. 2. Membrane preparations of alpha 1- and beta 2-adrenergic binding sites were obtained from urinary bladder and urethrae of sheep. These binding sites were characterized by saturation analyses using [3H]-prazosin for alpha 1-adrenoceptor binding sites and [125I]-cyanopindolol (CYP) for the beta 2-adrenoceptor binding sites. The receptors were further characterized by displacement studies using selective and non-selective antagonists. 3. Studies in which ketamine was used to displace [3H]-prazosin revealed a Kd of 3.40 +/- 1.23 x 10(-3) mol/L for ketamine binding to alpha 1-adrenoceptors. Displacement studies of [125I]-CYP by ketamine showed a Kd of 0.35 +/- 0.03 x 10(-3) mol/L for ketamine binding to beta 2-adrenoceptors. 4. We conclude that ketamine interacts directly with both alpha 1- and beta 2-adrenoceptors and that such interactions probably explain the reported effects of this agent on the vasculature and the bronchial tree.

Effect of an AIDS education program for older adults

The purpose of this study was to examine the effect of an age-specific AIDS education program on HIV/AIDS knowledge, perceived susceptibility to AIDS, and perceived severity of AIDS in older adults. The health belief model served as a framework. The age-specific AIDS education program was developed based on a knowledge, beliefs, and behaviors survey of 458 older adults at senior citizen centers. The program included case study presentations of actual older people with AIDS along with an emphasis on myths identified in the initial survey. There was a significant increase in total knowledge about AIDS (p < .001), perceived susceptibility (p < .01), and perceived severity (p < .001) after the educational program. Based on the results of this study, nurses are in an excellent position to provide primary and secondary AIDS prevention strategies for all age groups, including the older adult population.

Attitudes toward condom use among female college students

The purpose of this study was to explore attitudes toward condom use, identify the frequency of condom usage, and examine the relationship between attitudes and condom use among sexually active female college students. This descriptive study used a convenience sample of 47 female college students attending a rural county family planning clinic. Students who reported condom use scored significantly higher on the Condom Attitudes Scale than those not using condoms. Other significant differences between condom and noncondom users were noted. The results provide insight into strategies for improving safer sexual behavior through nursing interventions for college populations.

Quality of life and coping styles of HIV-positive women with children

This descriptive study explored the quality of life and coping methods of HIV positive women (N = 52) with children. The sample consisted of women with HIV/AIDS who answered an adapted Padilla Quality of Life Index and the Jalowiec Coping Scale. Among the psychological, physical, and social quality of life subscales, social quality of life was rated highest and the psychological scale rated the lowest. Among the three styles of coping, confrontive was used most frequently, passive and emotive less frequently. Significant relationships between coping and quality of life were examined. It is essential that nurses working with women with HIV disease be aware of their common concerns and provide effective strategies to improve quality of life such as enhancing decision making and coping skills within the context of the family unit.

Identifying patient symptoms after radiotherapy using a nurse-managed telephone interview

PURPOSE/OBJECTIVES

To identify patients' symptoms following completion of radiotherapy for common cancers by a nurse-managed telephone interview.

DESIGN

Quality assurance project.

SETTING

Radiation therapy department in a community hospital in a large midwestern city.

SAMPLE

One hundred eleven patients treated by radiotherapy for primary cancer of the prostate, head/neck, lung, and breast.

METHODS

Two time points of data collection: nurses completed an end-of-treatment symptom evaluation within the last five days of treatment and conducted telephone interviews 14-21 days post-therapy. Interview questions were based on each individual's end-of-treatment symptoms and common site-specific side effects.

MAIN RESEARCH VARIABLES

Symptoms at end of treatment and 14-21 days after therapy completion, nursing assessments and interventions, and length of telephone interview.

FINDINGS

At the end of treatment, 104 (94%) patients were experiencing symptoms. Nurses contacted 106 (95%) patients by telephone 14-21 days after therapy completion and assessed symptoms in 84 (79%) patients. Nineteen (18%) patients reported the development of a new symptom. Nurses independently managed 95% of the calls.

CONCLUSIONS

The majority of patients experienced symptoms in the immediate post-therapy period. Telephone follow-up interviews served as a mechanism for evaluating short-term morbidity and provided the opportunity for nurses to intervene with many patients.

IMPLICATIONS FOR NURSING PRACTICE

A nurse-managed telephone follow-up program can be used as a component of a quality improvement process in radiation centers to assess patients' post-treatment symptoms and provide education and support.

Knowledge of human immunodeficiency virus and acquired immunodeficiency syndrome, perception of risk, and behaviors among older adults

In a study of knowledge and beliefs about human immunodeficiency virus among older persons, 458 senior center participants completed a questionnaire derived from the Health Belief Model. The older adults had a fairly good knowledge base about acquired immunodeficiency syndrome (AIDS). Although they recognized the seriousness of the disease, they generally did not believe that they were susceptible to AIDS. Those who expressed an interest in receiving AIDS education had significantly higher perceived susceptibility scores than those who did not. African American respondents were statistically more interested in AIDS education than white or Hispanic respondents. Recommendations for interventions and further research are discussed.

Evaluation of oncology registry follow-up methods

BACKGROUND

The accuracy and completeness of oncology (tumor) registry patient follow-up information directly affects the validity of the oncology registry system for determining outcomes, as a quality assurance measure, and for research activities. At this institution, if a hospital-based patient encounter has not been identified during the previous year, a follow-up letter is sent to the attending physician to obtain current information about the patient. Difficulties using this method include (1) correct identification of the appropriate physician (2) constraints on physician and staff time to provide information, and (3) accuracy, currentness, and completeness of information provided.

METHODS

A study was conducted to compare the accuracy and completeness of the oncology registry patient follow-up information obtained from three sources: responses from the patient, responses from the physician, and affiliated clinic chart reviews. Seven hundred ninety-one patient and physician letters were sent during a 2-month period, and 122 clinic charts were reviewed.

RESULTS

Physicians responded more frequently than patients (82% vs. 58%) (P < 0.003). From the responses received, requested information regarding recurrence, treatment, quality of survival, and survival was obtained most frequently from patients. However, it was difficult to ascertain information about cancer status from patient responses. Patients supplied more current follow-up information than physicians or the clinic chart reviews.

CONCLUSIONS

A follow-up system that delivers accurate and complete information while maintaining efficiency is a critical aspect of an oncology registry. Requesting follow-up information from the patient before physician contact or chart review allows for more current information while maintaining accuracy regarding cancer recurrence, treatment, quality of survival, and survival. Consequently, staff time required for obtaining follow-up information from physicians and/or chart reviews is lessened and costs decreased.

Recognition and evaluation of oncology-related symptoms in the emergency department

STUDY OBJECTIVE

To identify the oncology patient population presenting to the emergency department and examine the causes and clinical management of oncology symptoms in the ED.

DESIGN

Retrospective review of 5,640 adult patients, with the following variables identified for oncology patients presenting to the ED: age, sex, cancer type, cancer stage, previous cancer treatment, previous hospitalization, presenting symptoms, treatment provided in the ED, admission and discharge data, and day, time, and length of ED visit.

SETTING

Community teaching hospital with annual ED census of 31,000.

PARTICIPANTS

All adult oncology patients who presented to the ED during the study period. We identified these patients by cross-referencing ED logs and tumor registry records.

RESULTS

Cancer history was identified for 284 of the 5,640 adult ED admissions (5%). Forty-three percent (n = 122) of the 284 patients with cancer history had an oncology-related ED visit. The most common symptoms of these patients were gastrointestinal (48%), pain (40%), neurologic (38%), cardiac (25%), and pulmonary (23%). Ten percent of patients with oncology-related ED visits died during the admission, and 48% died within 1 year of the ED visit.

CONCLUSION

Oncology patients present to the ED with symptoms of undiagnosed malignancy, complications of cancer treatment, and acute disease-related symptoms. Knowledge of an individual's cancer history and ability to recognize oncologic symptoms are important to the management of oncology patients.

Empathic learning: an innovative teaching strategy to improve attitudes toward caring for persons with HIV/AIDS

The authors conducted a pretest-posttest experimental study to explore the effect of an innovative teaching strategy ("The Circle of Life") on nursing students' knowledge, attitudes, and concerns about caring for persons with AIDS (PWAs). The students (N = 43) who participated in the intervention demonstrated a statistically significant improvement in attitudes toward PWAs. Interventions such as this one, which engage the affective response, have potential for improving attitudes toward caring for individuals with stigmatizing conditions.

Phase II trial of external beam radiation with etanidazole (SR 2508) for the treatment of locally advanced prostate cancer

PURPOSE

To evaluate the efficacy and toxicity of the addition of etanidazole (ETA) to external beam radiation.

METHODS AND MATERIALS

Fifty eight previously untreated patients with locally advanced adenocarcinoma of the prostate were entered on a Phase II trial of etanidazole (ETA) combined with standard external beam radiation therapy. ETA was given concurrently with irradiation. Four patients received less than 25% of the intended dose of ETA and were ineligible for further analysis. The stage of the remaining patients were T2c-11, T3-39, T4-1, bulky local recurrence after prostatectomy-1, and T3, N1-2.

RESULTS

Forty-five of 54 patients (83.3%) achieved a clinical complete response (CCR) in the prostate and seminal vesicles as judged by digital rectal exam (DRE). Responses were rapid with a median time to CCR of 3.4 months, range 0-22.8 months. Local control was maintained in 82% of the patients who achieved a CCR. Fifteen of 32 eligible patients with a normal DRE underwent prostate biopsies from 12-20 months after treatment, seven had negative biopsies (46.6%). Distant metastases occurred in 18 patients (33.3%). Pretreatment prostatic specific antigen (PSA), Gleason score, and stage were not associated with treatment outcome in a univariate analysis.

CONCLUSION

While ETA plus radiation was associated with a rapid CCR, the overall treatment outcome of these patients appeared to be similar to published reports of patients receiving RT alone. The rapid response rate may imply biologic activity of the ETA. In future trials, it may be reasonable to focus on patients at lower risk for the subsequent development of distant disease.

Health concerns of women with HIV/AIDS

The author's purpose was to explore the health concerns of women with HIV/AIDS. Eleven HIV-positive women were interviewed using the Omaha System to organize the interview data for content analysis. Data were classified into environmental, health-behavioral, physiological, and psychosocial concerns. Comparisons of the African-American and white women presented more similarities than differences, except for noncompliance with zidovudine therapy. Implications of this study for health professionals include the need to identify support systems for women with HIV/AIDS, to identify ways to encourage women to focus on their own health, to assess for depression and suicide risk, and to refer to appropriate community resources in a timely fashion.

Evaluation of a peer-education program on heart disease prevention with older adults

This investigation evaluated the effect of a peer-education program on preventing cardiovascular disease in older persons. Peer leaders at two urban senior housing residences were provided with training on cardiovascular disease and its risk factors, strategies to reduce the risk factors, and communication skills. Baseline and follow-up data were collected on residents at the two intervention and two control sites. The dependent variables were knowledge of cardiovascular disease risk factors; perceived self-efficacy to reduce calories, dietary fat and salt intake, to lose weight, to stop smoking, and to exercise regularly; and self-reported cardiovascular risk behaviors. Analysis of individual change scores between baseline and follow-up surveys showed a statistically significant increase in overall knowledge of heart disease, dietary self-efficacy, and exercise self-efficacy for the intervention group compared with the control group. This program appeared to benefit the individuals who lived in housing residences where the peer educators also resided.

Implementation issues in home healthcare universal precautions

Universal precautions in home healthcare are essential, yet cost and compliance monitoring are major barriers to their implementation. To help administrators ensure adherence to universal precautions, the authors present specific strategies, including management commitment, a comprehensive training program sensitive to the educational level of the employee, and participation of employees in the continuing implementation and evaluation of the universal precautions policy.

The efficacy of pharmacokinetic monitoring and dose modification of etanidazole on the incidence of neurotoxicity: results from a phase II trial of etanidazole and radiation therapy in locally advanced prostate cancer

Fifty-four patients have been entered on a Phase II trial to study the efficacy of etanidazole (ETA) for locally advanced prostate cancer. The primary goal was to study the incidence of and time to a complete response for patients receiving ETA and radiation therapy. The secondary goal was to prospectively evaluate the utility of pharmacokinetic monitoring and dose-modification of the incidence and severity of the dose-limiting peripheral neurotoxicity. Within a constant radiation therapy regimen, the dose of ETA was either (a) unmodified (2 g/m2, 3 times weekly for 17 doses); (b) altered by a schedule modification of either number of doses or dose adjustment; or (c) individualization of single dose size so that the total number of doses (19 doses) were maintained but the single dose size was adjusted to keep the total AUC of plasma concentration versus time to less than 40 mM-hr. Sufficient efficacy data are not yet available. The use of drug dose modification has reduced the incidence of neurotoxicity from (a) unmodified: 17/26 = 65% (1 grade II); (b) schedule adjustment: 5/9 = 55% (no grade II); and (c) individualized dose modification: 1/19 (no grade II) = 6%. The minimum number of time points needed to accurately assess the AUC will be determined. Pharmacokinetic monitoring will be important in the use of ETA so that drug underdosing can be avoided while minimizing the risk of serious neurotoxicity.

Intervention strategies for smoking cessation. The role of oncology nursing

The role of oncology nurses concerned with the health effects of cigarette smoking may often be defined as dealing with the morbidity and mortality associated with tobacco use--caring for individuals diagnosed with tobacco-related malignancies. As current treatment methods of many of these malignancies offer little hope of cure, oncology nurses need to diverge from these traditional roles and include a focus on primary prevention activities. An essential component of these activities is a knowledge of smoking cessation education strategies and an understanding of the methods that motivate and assist individuals to quit smoking.

Late cosmetic outcome after conservative surgery and radiotherapy: analysis of causes of cosmetic failure

Although the majority of patients with early breast cancer treated with conservative surgery and radiotherapy have acceptable cosmetic outcomes, the specific causes of a less-than-acceptable result are not well known. To assess the technical factors associated with late cosmetic failure, we reviewed the records of 593 patients treated with conservative surgery and radiotherapy at the Joint Center for Radiation Therapy, Boston, between 1968 and 1981. Median follow-up was 76 months with a range of 37-186 months. Using a 4-point scoring system (excellent, good, fair, poor) patients were noted to have cosmetic "failure" if scored as either fair or poor. Cosmetic results were similar at 3, 5, and 7 years with excellent or good scores seen in 88%, 90%, and 78% of patients, respectively. Three technical factors were associated with a significant worsening of the cosmetic results. The resection of 70 cm3 or more of breast tissue was more common among the failed patients than among matched patients with good or excellent results (p = 0.03). Eighty-nine percent of patients treated with a tangent pair technique had excellent results at 5 years compared to 69% of patients treated with a three-field technique (p = 0.004). The use of a larger volume implant was associated with a greater risk of a fair or poor cosmetic result compared to the use of a smaller volume implant. We conclude that overall cosmesis has been acceptable in this series, but there are technical (surgery and radiotherapy) factors which can be modified to optimize the cosmetic result without compromising local tumor control.