Energy input and response from prompt and early optical afterglow emission in gamma-ray bursts.

The taxonomy of optical emission detected during the critical first few minutes after the onset of a gamma-ray burst (GRB) defines two broad classes: prompt optical emission correlated with prompt gamma-ray emission, and early optical afterglow emission uncorrelated with the gamma-ray emission. The standard theoretical interpretation attributes prompt emission to internal shocks in the ultra-relativistic outflow generated by the internal engine; early afterglow emission is attributed to shocks generated by interaction with the surrounding medium. Here we report on observations of a bright GRB that, for the first time, clearly show the temporal relationship and relative strength of the two optical components. The observations indicate that early afterglow emission can be understood as reverberation of the energy input measured by prompt emission. Measurements of the early afterglow reverberations therefore probe the structure of the environment around the burst, whereas the subsequent response to late-time impulsive energy releases reveals how earlier flaring episodes have altered the jet and environment parameters. Many GRBs are generated by the death of massive stars that were born and died before the Universe was ten per cent of its current age, so GRB afterglow reverberations provide clues about the environments around some of the first stars.

A link between prompt optical and prompt gamma-ray emission in gamma-ray bursts.

The prompt optical emission that arrives with the gamma-rays from a cosmic gamma-ray burst (GRB) is a signature of the engine powering the burst, the properties of the ultra-relativistic ejecta of the explosion, and the ejecta's interactions with the surroundings. Until now, only GRB 990123 had been detected at optical wavelengths during the burst phase. Its prompt optical emission was variable and uncorrelated with the prompt gamma-ray emission, suggesting that the optical emission was generated by a reverse shock arising from the ejecta's collision with surrounding material. Here we report prompt optical emission from GRB 041219a. It is variable and correlated with the prompt gamma-rays, indicating a common origin for the optical light and the gamma-rays. Within the context of the standard fireball model of GRBs, we attribute this new optical component to internal shocks driven into the burst ejecta by variations of the inner engine. The correlated optical emission is a direct probe of the jet isolated from the medium. The timing of the uncorrelated optical emission is strongly dependent on the nature of the medium.

Prompt Optical Observations of Gamma-Ray Bursts.

The Robotic Optical Transient Search Experiment (ROTSE) seeks to measure simultaneous and early afterglow optical emission from gamma-ray bursts (GRBs). A search for optical counterparts to six GRBs with localization errors of 1 deg2 or better produced no detections. The earliest limiting sensitivity is mROTSE>13.1 at 10.85 s (5 s exposure) after the gamma-ray rise, and the best limit is mROTSE>16.0 at 62 minutes (897 s exposure). These are the most stringent limits obtained for the GRB optical counterpart brightness in the first hour after the burst. Consideration of the gamma-ray fluence and peak flux for these bursts and for GRB 990123 indicates that there is not a strong positive correlation between optical flux and gamma-ray emission.

Demonstration of literal three-dimensional imaging.

In a recent paper a new technique was proposed for remote ranging and topographical mapping by using a system with a single-photon-counting detector and a low-power pulsed laser [Appl. Opt. 35, 441 (1996)]. We report on the results from the laboratory and the field demonstration of this literal three-dimensional imaging technique. Using a detector system developed at Los Alamos with a commercial pulsed laser and observing from a single remote vantage point, we demonstrate use of this technique in the literal mapping of three-dimensional topography and the probing of a complex scene. With a reasonably short exposure this system can resolve features with height variations as small as 5 cm.

Paraneoplastic syndromes in metastatic disease.

OBJECTIVES: To provide an overview of selected paraneoplastic syndromes associated with metastatic disease with potential life-threatening implications, and the nursing implications of each. DATA SOURCES: Published articles and book chapters related to paraneoplastic syndromes in metastatic disease. CONCLUSIONS: Paraneoplastic syndromes in metastatic disease are associated with various primary tumors and can affect many organ systems. Early recognition and management can minimize the potential life-threatening effects of the syndromes. IMPLICATIONS FOR NURSING PRACTICE: Oncology nurses need to be aware of the potential for paraneoplastic syndromes that can compromise a patient's health status. Appropriate assessment and intervention of paraneoplastic syndromes can have a positive impact on patient outcomes and quality of life.

Exploring the psychosocial meaning of recurrent cancer: a descriptive study.

Many persons diagnosed with malignancy will experience one or more recurrences of malignancy. Little is known about the psychosocial meaning of recurrent cancer. Using Lazarus and Folkman's model of stress, appraisal and coping, the two purposes of this descriptive study were to (a) describe the meaning of a recurrence of cancer to the patient and (b) to explore if the patient perceives the diagnosis of recurrence as being different from the initial diagnosis of cancer. Purposeful sampling for persons with recent recurrent malignancy produced a sample (n = 20). Subjects completed an unstructured, indepth interview. The meaning of the recurrence was influenced by prior cancer-related experiences of the subjects and dominated by death and death-related concerns. Differences from the initial diagnosis included a deeper awareness of the significance of the "cancer diagnosis".

Psychosocial concerns associated with recurrent cancer.

Little research has been directed toward the needs of those with recurrent cancer. The purpose of this descriptive study was to describe the psychosocial problems and concerns associated with recurrence. Purposeful sampling for persons with recent recurrent malignancy produced a sample (N = 20) with diverse medical and demographic characteristics. Subjects completed the Psychosocial Adjustment to Illness Scale and an audiotaped structured interview to discuss the responses on the Psychosocial Adjustment to illness Scale in depth. Specific areas explored in the interviews included health-related issues, work and financial concerns, family and marital relationships, relationships with friends, and psychological distress. Verbatim transcripts were analyzed for themes and trends and double-coded with 94% Inter-rater agreement. Psychosocial Adjustment to Illness Scale scores were high, suggesting that this group has many psychosocial needs. Implications for health professionals include a need for thorough psychosocial assessment and improved communication with these patients.

Hereditary cancer syndrome: Part 1.--Clinical and educational issues.

PURPOSE/OBJECTIVES: To review current information on the biology and characteristics of hereditary cancer syndromes (HCS), and to identify families with HCS, various methods to communicate the diagnosis to families, and associated considerations for clinical practice and education. DATA SOURCES: Published articles and book chapters. DATA SYNTHESIS: HCS, which accounts for approximately 5%-10% of all malignancies, is characterized by diagnosis of the same malignancy in multiple family members, an earlier age of onset than expected, an increased frequency of bilateral cancers in paired organs, and the presence of premalignant syndromes. CONCLUSIONS: Identifying families with HCS and referring them to screening programs are necessary to reduce morbidity and mortality in these families. Many clinical, educational, and research issues are emerging. IMPLICATIONS FOR NURSING PRACTICE: Nurses need to be aware of HCS in order to identify families with HCS and refer them to screening programs. Information about HCS needs to be incorporated into basic, graduate, and continuing education nursing programs to increase awareness of HCS. Further nursing research is needed to better understand the best way to communicate the diagnosis to families, identify the psychosocial needs of individuals from these families, and facilitate cancer prevention and detection measures in these families.

Hereditary cancer syndrome: Part 2.--Psychosocial issues, concerns, and screening--results of a qualitative study.

PURPOSE/OBJECTIVES: To describe the feelings and concerns of family members with hereditary cancer syndrome (HCS) and their level of participation in prevention and early detection activities. DESIGN: Qualitative methods; content analysis of interviews. SETTING: Community, hospital-based cancer screening center with a special program of supportive services for families with HCS. SAMPLE: Purposeful theoretical sampling produced a sample (n = 13) of people with HCS. Most were Caucasian women representing a variety of types of HCS. METHODS: In-depth, unstructured, audiotaped interviews that lasted about 60 minutes. FINDINGS: Five themes emerged: (a) issues regarding communication with health professionals, (b) relationships with family members, (c) financial concerns, (d) psychosocial concerns, and (e) participation in screening activities. CONCLUSIONS: Individuals from families with HCS live with the knowledge that they have a high risk of developing malignancy. A true understanding of this risk may take time to comprehend. Many members of families with HCS require more education and support regarding cancer screening and prevention activities. IMPLICATIONS FOR NURSING PRACTICE: Nursing roles include being an educator on risk and early detection measures, a patient advocate, and a resource to all members of the family with HCS. Future nursing research can help identify specific psychosocial needs among different family members and specific psychosocial needs associated with different types of HCS.

Safe handling practices of cytotoxic drugs: the results of a chapter survey.

PURPOSE/OBJECTIVES: To describe how nurses from a local Oncology Nursing Society (ONS) Chapter Implement Occupational Safety and Health Administration (OSHA) guidelines for handling cytotoxic drugs (CDs) in their individual practices and to identify barriers to implementing these guidelines. DESIGN: Mailed survey. SETTING: ONS chapter in a large midwestern city. SAMPLE: 103 nurses, 83 of whom handle CDs. Mean years in oncology nursing was 7.5. METHODS: Mailed survey consisting of 48 questions on seven topics, as well as demographic questions. MAIN RESEARCH VARIABLES: Roles in preparation and administration of CDs, management spills, patient care, and use of protective equipment in patient and family education practices; barriers to use of protective practices. FINDINGS: Subjects used some protective equipment when preparing and administering CDs, but the type of equipment and its frequency of use did not specifically meet OSHA Guidelines. Rates of compliance with guidelines were better for management of spills and disposal of equipment. Verbal instructions for patients and families were employed but very few provided written instructions or explanations. Barriers to using protective equipment included a lack of time, problems with availability, and concerns about patient reactions. CONCLUSIONS: Barriers must be overcome and better safe-handling practices incorporated into practice to ensure the safety of nurses. More education is needed for family members who come into contact with patients receiving CDs. IMPLICATIONS FOR NURSING PRACTICE: Future research to document the extent of the problem, including stratification of responses according to the quantity and frequency with which a nurse administers CDs. Better, and perhaps more frequent, staff and family education efforts are needed.

Benefits of collaboration in continuing education: a partnership between a university provider and a nursing specialty organization.

During the past 2 years, a university provider of nursing continuing education and the local chapter of a specialty nursing organization have successfully collaborated in the delivery of continuing education. This collaborative approach has been effective for providing continuing education in oncology nursing that serves the needs of nurses in the geographic area and maximizes the effective use of the resources of both partners. This approach has also prevented overlaps in program planning dates and duplication of content within the geographical area. Additional benefits include a growth in membership for the specialty organization and a sustained level of interest and attendance in programs sponsored by the university provider.

Focus on oncology: vasectomy and the risk of prostate cancer.

PIP: Around 10% of US men will be diagnosed with prostate cancer at some point in their life. Recent studies of the association between vasectomy and prostate cancer show conflicting results and weaknesses in methodologies. A retrospective cohort analysis of men aged 25-49 who had had a vasectomy between 1970 and 1986 did not find a link between vasectomy and an increased incidence in prostate cancer. In another retrospective study, 96 of 14,607 men who had had a vasectomy between 1976 and 1978 developed prostate cancer. In a prospective study conducted between 1986 and 1990, 300 of 10,500 men aged 40-75 who had had a vasectomy developed prostate cancer. In the latter two studies, vasectomy was found to be associated with an increased risk of prostate cancer, especially as time since vasectomy increased. This increased risk remained even when one controlled for lifestyle variables (both studies) and body mass index and area of residence (prospective study). The strengths of these studies are large sample sizes and controlling for lifestyle variables. The studies indicate that vasectomy may cause prostate cancer. Small increases in circulating androgen levels, which follow vasectomy, may facilitate prostate cancer development. The immune response to sperm antigens after vasectomy may promote tumor growth by blocking antibodies or tumor suppressor cells by sperm antigens. The vasectomy may keep inhibitors of cancer enhancing growth factors from reaching the prostate, thereby promoting prostate cancer. After vasectomy, there may be a reduced secretory rate of prostatic fluid, prolonging exposure to carcinogenic factors in this fluid. Urology nurses need to be up-to-date on these studies and be able to clarify the conflicting results for patients. They need to tell them that vasectomy may be linked to an increased risk of prostate cancer and that more information is needed. They must encourage men aged 40 and over to undergo regular prostate cancer screening. Men at high risk should be screened younger than age 40.^ieng

Pathophysiology of hypokalemia in patients with cancer: implications for nurses.

Hypokalemia is a potentially life-threatening complication that occurs in many patients with cancer. Nurses need to be aware of the many common causes of this electrolyte disorder as well as appropriate assessment strategies that will enable potential problems to be detected and treated early. This article begins with a review of normal potassium balance and physiology, followed by a discussion of potential causes of hypokalemia in patients with cancer. These causes are grouped into four categories: inadequate dietary intake, extrarenal losses, redistribution abnormalities, and renal losses. Common causes of hypokalemia in patients with cancer are illustrated with case examples. Signs and symptoms associated with hypokalemia are discussed. Finally, implications for nursing assessment and intervention related to the administration of potassium are reviewed.

Teaching women about mammography through use of a brochure.

This paper describes the development and use of a brochure intended to educate women about the nature and benefits of mammography. This brochure, which is presented in its entirety, has several unique features. It addresses the myths associated with mammograms and includes a visual depiction of the difficult-to-understand concept of relative difference with respect to size of breast lesions.