Turbulent heating in galaxy clusters brightest in X-rays.

The hot (10(7) to 10(8) kelvin), X-ray-emitting intracluster medium (ICM) is the dominant baryonic constituent of clusters of galaxies. In the cores of many clusters, radiative energy losses from the ICM occur on timescales much shorter than the age of the system. Unchecked, this cooling would lead to massive accumulations of cold gas and vigorous star formation, in contradiction to observations. Various sources of energy capable of compensating for these cooling losses have been proposed, the most promising being heating by the supermassive black holes in the central galaxies, through inflation of bubbles of relativistic plasma. Regardless of the original source of energy, the question of how this energy is transferred to the ICM remains open. Here we present a plausible solution to this question based on deep X-ray data and a new data analysis method that enable us to evaluate directly the ICM heating rate from the dissipation of turbulence. We find that turbulent heating is sufficient to offset radiative cooling and indeed appears to balance it locally at each radius-it may therefore be the key element in resolving the gas cooling problem in cluster cores and, more universally, in the atmospheres of X-ray-emitting, gas-rich systems on scales from galaxy clusters to groups and elliptical galaxies.

A massive, cooling-flow-induced starburst in the core of a luminous cluster of galaxies.

In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2 × 10(45) erg s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.

Discrete sources as the origin of the Galactic X-ray ridge emission.

An unresolved X-ray glow (at energies above a few kiloelectronvolts) was discovered about 25 years ago and found to be coincident with the Galactic disk-the Galactic ridge X-ray emission. This emission has a spectrum characteristic of a approximately 10(8) K optically thin thermal plasma, with a prominent iron emission line at 6.7 keV. The gravitational well of the Galactic disk, however, is far too shallow to confine such a hot interstellar medium; instead, it would flow away at a velocity of a few thousand kilometres per second, exceeding the speed of sound in the gas. To replenish the energy losses requires a source of 10(43) erg s(-1), exceeding by orders of magnitude all plausible energy sources in the Milky Way. An alternative is that the hot plasma is bound to a multitude of faint sources, which is supported by the recently observed similarities in the X-ray and near-infrared surface brightness distributions (the latter traces the Galactic stellar distribution). Here we report that at energies of approximately 6-7 keV, more than 80 per cent of the seemingly diffuse X-ray emission is resolved into discrete sources, probably accreting white dwarfs and coronally active stars.

On the 10th anniversary of the organization of the American Academy of Hospice and Palliative Medicine (AAHPM): the first 10 years.

The American Academy of Hospice and Palliative Medicine (originally chartered as the Academy of Hospice Physicians in 1988) is an organization of physicians devoted to advancing hospice and palliative medicine in the United States. The academy's mission is "physicians dedicated to promoting quality hospice care for the terminally ill through medical education, research, and training." The academy obtained specialty recognition from the AMA in 1996 and became the first physicians' group to publish its position on physician-assisted suicide in 1991 and again in 1997.

A Chandra High-Resolution X-ray Image of Centaurus A.

We present first results from a Chandra X-Ray Observatory observation of the radio galaxy Centaurus A with the High-Resolution Camera. All previously reported major sources of X-ray emission including the bright nucleus, the jet, individual point sources, and diffuse emission are resolved or detected. The spatial resolution of this observation is better than 1&arcsec; in the center of the field of view and allows us to resolve X-ray features of this galaxy not previously seen. In particular, we resolve individual knots of emission in the inner jet and diffuse emission between the knots. All of the knots are diffuse at the 1&arcsec; level, and several exhibit complex spatial structure. We find the nucleus to be extended by a few tenths of an arcsecond. Our image also suggests the presence of an X-ray counterjet. Weak X-ray emission from the southwest radio lobe is also seen, and we detect 63 pointlike galactic sources (probably X-ray binaries and supernova remnants) above a luminosity limit of approximately 1.7x1037 ergs s-1.

Incorporating education on palliative care into the long-term care setting. National Consensus Conference on Medical Education for Care Near the End of Life.

Approximately one-third of all Americans will pass through a long-term care facility before they die, and many who require palliative care will reside there during the final weeks and months of their lives. In order to address this need, the unique characteristics of long-term care facilities are outlined, and the incentives for all levels of academic institutions to offer education in that setting are presented.

Formal geriatric assessment, An imperative for the older person with cancer.

PURPOSE: The authors evaluate the role of cognitive, functional, and affective geriatric assessment measures in elderly cancer patients, and analyze the associations between these factors, stage of malignancy, and cancer treatment choices. DESCRIPTION: Fifty consecutive patients older than 65 years of age who were referred to the Geriatric Oncology Clinic at the University of New Mexico Health Sciences Center in Albuquerque were evaluated using standard geriatric assessment tools. Each person underwent a complete history and physical examination. An extensive chart review established the type of cancer, stage at diagnosis, and treatment modalities used. The Karnofsky performance status scale score also was determined at this initial evaluation. RESULTS: The group had a mean age of 74.9 years; 60% were women and 40% were men. The most common cancers were breast (28%) and prostate (16%). Fifty-two percent of the patients had localized disease and 48% had distant disease. Seventy-four percent had received treatment by the time of the initial assessment, with 62% undergoing combination therapy. The most common noncancer diagnoses were cardiovascular disease, hypertension, and osteoarthritis. Scores on standardized measures indicated that the majority of patients were independent. Those who did not receive treatment were more functionally impaired than those who received treatment. Twenty-seven percent of the sample were impaired cognitively and 24% were depressed. There were no statistical differences in functional, cognitive, or affective status between stages of disease for specific malignancies. CLINICAL IMPLICATIONS: Age alone is a poor predictor of outcome in cancer treatment and is an inappropriate factor by which to exclude persons with cancer from clinical trials. Treatment decisions based on age alone may lead to inadequate treatment. In this report, functional dependence was more prevalent in nontreated patients and was unrelated to the stage of disease. These results support the need for formal geriatric assessment, including measures of cognitive, functional, and affective status, in elderly persons with cancer. Further studies on the role of functional, cognitive, and affective status at the time of cancer diagnosis, as well as how these parameters might alter treatment decisions, are warranted. In addition, further investigation to identify which of these multiple variables influence treatment outcome are needed.

Life expectancy, comorbidity, and quality of life. A framework of reference for medical decisions.

The treatment of cancer in the elderly can benefit from increasingly sophisticated methods that measure a patient's quality of life. These measures are both general and cancer specific and herald a new and enlightened approach to patient care. The care of the older patient must be seen in light of what is known about life expectancy, the outcome of treatment, an awareness of comorbidity, and the importance of informed consent and respect for the values and preferences of the individual patient. This article reviews the growing literature on quality of life research in cancer patients.

Symptomatic management of the older person with cancer.

The older person with cancer is often unable to participate in treatment regimens that a younger person might tolerate. We review the complex reasons why this may be so as well as provide to the reader a brief review of the major symptoms that can cause suffering and treatment regimens that can improve the patient's sense of well being. Palliative care provides the older person with advanced cancer the opportunity to live his or her life to the fullest during that period of life called dying.

Opioid analgesic drugs in the elderly.

Much is known about opioid metabolism, which is critical in administering these agents to the elderly. Fear of addiction and tolerance are the major barriers to their use among patients as well as health-care professionals. Addressing these issues early in the initiation opioid therapy will help to alleviate these concerns. Once therapy with an opioid is initiated, the role of renal function is critical. Because many metabolites of the opioids are renally cleared and have activity either in analgesia or as undesired side effects, it is critical to be aware of the creatinine clearance (not just serum creatinine) in the elderly. The initiating doses of the opioids can be equal to that of younger patients, but the clinician should anticipate using a longer frequency of dosing interval or smaller doses during the course of therapy. Methadone, propoxyphene, and meperidine are not recommended for use in elderly people, because of the toxicity of their metabolites. Of all the unwanted effects of the opioids, the most difficult to deal with is that of constipation. Here, an aggressive approach using bowel stimulating laxatives is critical in order to prevent this problem. It is anticipated that a variety of newly formulated opioids will shortly be available for clinical use. Finally, as a better understanding of the neurophysiology of pain is gained, the clinician can anticipate having more analgesic opioids that target their receptors without agonist or antagonist effect on other opioid receptors. This will allow the clinician to better relieve pain with a minimum of unwanted side effects.

Abscess formation in desmoid tumors of Gardner's syndrome and percutaneous drainage: a report of three cases.

PURPOSE: To describe abscess formation complications in desmoid tumors of patients with Gardner's syndrome and percutaneous drainage. METHODS: Three patients with Gardner's syndrome and intramesenteric desmoid tumors were diagnosed as having intratumor abscess formation. Percutaneous drainage was the initial method of treatment in each case. Two subsequently underwent surgical resection and one patient refused surgery and was lost to follow-up. RESULTS: In each case, percutaneous drainage and antibiotics resulted in clinical improvement. In two, fistulous communication with the small bowel could be demonstrated, presumed to be the cause of abscess formation. Surgical resection confirmed fistula communication to the small bowel. In the third patient, no fistula was seen and only percutaneous drainage was performed. CONCLUSION: Abdominal pain and fever in patients with Gardner's syndrome and desmoids is suggestive of abscess formation in these tumors. Percutaneous drainage is useful as initial management.

A community survey of ptosis of the eyelid and pupil size of elderly people.

A randomly selected, age-stratified sample of subjects 50 years of age and older, living in the Salford Health District area of Greater Manchester was drawn from the age-sex register of a four-doctor group practice and invited by post to enter a study of ptosis. Of 851 subjects approached, 499 (59%) replied. Of these, 99 refused to participate. The remaining 400 were visited at home and underwent a standardized protocol of ophthalmic history, and examination including a photograph of the eyes in the primary position. Forty-six (11.5%) of the subjects had ptosis and its prevalence increased with age. Ptosis was bilateral in 18 (39%) and unilateral in 28 (61%). In all but four cases, the ptosis was acquired. The cause was evident in 23 (50%), with 11 cases being due to mechanical ptosis and 12 to aponeurotic disinsertion secondary to a known pathology. A further 22 cases had primary aponeurotic disinsertion and there was one case of probable myasthenia gravis. The prevalence of pupillary diameter of 1 mm or less increased significantly with age.

The role of chemotherapy and adjuvant therapy in the management of colorectal cancer.

This review of the current literature related to the use of chemo- and adjuvant chemotherapy in colorectal carcinoma emphasizes the present dilemma in caring for people affected with this disorder. Adjuvant chemotherapy using combinations of 5-fluorouracil and levamisole clearly prolong survival, albeit, for only a small group of individuals. However, for the older person, this regimen may be associated with unacceptable toxicity and a physician's inability to deliver a dose-intensive course, as the authors currently understand it. Although quality of life is a clear concern of many older persons, little currently is available to evaluate this parameter during chemotherapy. It remains an important issue to address in the elderly person, because 35% of individuals found to have colorectal carcinoma are older than 65 years. Hopefully, better staging by incorporating molecular biologic techniques will assist in the effort to uncover the best regimens.

Investigation of a pseudo-outbreak of orthopedic infections caused by Pseudomonas aeruginosa.

OBJECTIVE: To report a pseudoepidemic of Pseudomonas aeruginosa infections discovered during an investigation of postoperative joint infections. DESIGN: A retrospective review of case patients' hospital charts, operative reports, and laboratory data, as well as environmental culturing, polymerase chain reaction (PCR) ribotyping of outbreak isolates, and in vitro analysis of P aeruginosa growth characteristics. SETTING: A 510-bed, university-affiliated adult tertiary care hospital. RESULTS: Between October 1 and December 1, 1992, seven postsurgical joint infections were diagnosed, including four caused by P aeruginosa. A bottle of "sterile" saline used to process tissue specimens was found to be contaminated with P aeruginosa. Further investigation revealed that P aeruginosa had grown from seven additional tissue cultures, all of which had been processed with the contaminated saline. PCR ribotypes of the contaminant matched those of the clinical isolates. In vitro, P aeruginosa strains were viable in commercial nonbacteriostatic saline, but never caused visible turbidity. Six patients received antibiotics for their presumed infections; four patients had peripherally inserted central catheters placed, and one experienced severe anaphylactic reactions to several antibiotics. CONCLUSIONS: Pseudoepidemics due to common organisms are often difficult to detect, and delayed recognition can result in substantial morbidity. This outbreak investigation illustrates the potential for contamination of diluents in the microbiology laboratory and emphasizes the need for meticulous quality control.

Transdermal fentanyl disposition in elderly subjects.

The pharmacokinetic characteristics of a 20-cm2 fentanyl 24-hour transdermal patch were compared between 10 healthy elderly subjects 67-87 years and 6 young subjects 19-27 years. All 10 elderly subjects required patch removal prior to 24 h due to adverse effects versus none of the young subjects. The mean patch duration (PD) in elderly subjects was 11.7 +/- 4.9 h, yielding a mean area under the curve from 0 to 60 h (AUC0-60) of 20.4 +/- 10.3 ng h/ml versus a mean AUC0-60 of 21.0 +/- 10.4 ng h/ml in young subjects. Correcting AUC0-60 for PD (AUC0-60/PD) gave a mean value of 2.05 +/- 1.10 ng/ml for elderly subjects, which was significantly greater than the AUC0-60/PD of 0.88 +/- 0.44 ng/ml in young subjects (p = 0.034, Student's t test). The higher serum concentrations reflect increased absorption and/or decreased clearance in the elderly.

Pain management for the geriatric patient.

Pain is a common and complex problem in the geriatric population. Successful pain management in this patient population requires a comprehensive approach involving both pharmacologic and nonpharmacologic interventions.

A novel morphine sulphate preparation: clinical trial of a controlled-release morphine suspension in cancer pain.

In order to determine the efficacy of a novel controlled-release morphine suspension, we performed two prospective sequential open-label studies in patients with pain due to cancer. The studies were identical except for the duration of treatment (three days and 30 days respectively). Sixty-nine patients with a variety of advanced cancers and associated pain participated. Fifty-three patients completed the trials, 38 on the three-day trial and 15 on the 30-day trial. In both groups the amount of morphine required to obtain pain relief was initially established using controlled-release morphine tablets and immediate-release morphine for 'rescue' dosing. Patients were begun on equivalent doses of the study drug in place of the controlled-release tablets. No differences in pain score or the amount of 'rescue' morphine were noted following the switch to the controlled-release morphine suspension. Toxicity was as anticipated for the use of morphine in this situation and no adverse effects were observed during administration of the suspension. These data suggest that this new formulation of morphine is equipotent to conventional controlled-release morphine tablets and provides pain relief for a 12-hour dosing interval. This novel morphine formulation could be especially useful for paediatric patients and for those who have difficulty in swallowing.

Epidermal inclusion cysts following minimal incision surgery.

One of the most frequent causes of epidermal inclusion cysts is trauma involving the epidermis with subsequent implantation of epidermal cells into the dermis or subcutis. Minimal incision surgery is capable of achieving this because it is performed by using small incisions and rapidly rotating power instruments. The technique requires that the surgeon master a high degree of dexterity and knowledge of the anatomy without the aid of direct visualization. Van Enoo and Cane suggest the use of fresh, sharp skin blades to protect against invagination of skin edges which could lead to epidermal inclusion cysts. They also state that an improper position or an incision that is too small will cause tension, which can lead to heat buildup with subsequent sloughing and dehiscence. It may also drive some epidermal cells underneath the dermis and foster an epidermal cyst. Other surgeons using small incisions suggest thorough and copious irrigation to flush away debris and to avoid potential foreign body reactions. The periosteum should be reflected away from the point where the drill bit exits the bone to prevent bone chips from being forced subperiosteally and potentially causing a foreign body reaction. By virtue of the technique, minimal incision surgery lends itself to a greater risk of causing epidermal inclusion cysts. Surgeons who use these techniques must be aware of this potential complication.