Fatal pulmonary fat embolism after dorsal spinal fusion

OBJECTIVE: To determine whether health shop staff give specific therapeutic recommendations to someone who describes symptoms associated with serious pathology and to determine whether they refer this person to conventional medical care. DESIGN: Quantitative survey using participant observation. SETTING: Health food shops selling herbal, homeopathic or nutritional remedies in inner London. METHOD: A researcher visited 29 health food shops and claimed to be suffering from severe, daily headaches of recent onset. The researcher recorded on tape whether the health shop staff took diagnostic information; recommended any therapeutic intervention; asked about or recommended seeing a general practitioner (GP); asked about use of conventional drugs. Coding of the interactions was carried out independently by two researchers. RESULTS: Whereas all but two shops recommended a specific therapeutic intervention, less than one in four advised a GP consultation. Forty-two different interventions were recommended. There was little consistency in the advice given. CONCLUSION: Health food shops need to review the circumstances in which they should venture to provide advice and the basis on which they make any therapeutic recommendations. Shops selling over-the-counter herbal, homeopathic and health food products are a common feature of UK high streets. Such shops could be a useful source of health information and advice to their customers, but could also lead to harm, for example by delaying treatment of known benefit, if their recommendations were to be inaccurate or inappropriate.     

Ambulatory health care use by patients in a public hospital emergency department

OBJECTIVE: To describe primary care clinic use and emergency department (ED) use for a cohort of public hospital patients seen in the ED, identify predictors of frequent ED use, and ascertain the clinical diagnoses of those with high rates of ED use. DESIGN: Cohort observational study. SETTING: A public hospital in Atlanta, Georgia. PATIENTS: Random sample of 351 adults initially surveyed in the ED in May 1992 and followed for 2 years. MEASUREMENTS AND MAIN RESULTS: Of the 351 patients from the initial survey, 319 (91%) had at least one ambulatory visit in the public hospital system during the following 2 years and one third of the cohort was hospitalized. The median number of subsequent ED visits was 2 (mean 6.4), while the median number of visits to a primary care appointment clinic was O (mean 1.1) with only 90 (26%) of the patients having any primary care clinic visits. The 58 patients (16.6%) who had more than 10 subsequent ED visits accounted for 65.6% of all subsequent ED visits. Overall, patients received 55% of their subsequent ambulatory care in the ED, with only 7.5% in a primary care clinic. In multivariate regression, only access to a telephone (odds ratio [OR] 0.48; 95% confidence interval [CI] 0.39, 0.60), hospital admission (OR 5.90; 95% CI 4.01, 8.76), and primary care visits (OR 1.68; 95% CI 1.34, 2.12) were associated with higher ED visit rates. Regular source of care, insurance coverage, and health status were not associated with ED use. From clinical record review, 74.1% of those with high rates of use had multiple chronic medical conditions, or a chronic medical condition complicated by a psychiatric diagnosis, or substance abuse. CONCLUSIONS: All subgroups of patients in this study relied heavily on the ED for ambulatory care, and high ED use was positively correlated with appointment clinic visits and inpatient hospitalization rates, suggesting that high resource utilization was related to a higher burden of illness among those patients. The prevalence of chronic medical conditions and substance abuse among these most frequent emergency department users points to a need for comprehensive primary care. Multidisciplinary case management strategies to identify frequent ED users and facilitate their use of alternative care sites will be particularly important as managed care strategies are applied to indigent populations who have traditionally received care in public hospital EDs.     

Inositol 1,4,5-trisphosphate receptor expression in mammalian olfactory tissue

The interaction of recombinant ascorbate peroxidase (APX) with its physiological substrate, ascorbate, has been studied by electronic and NMR spectroscopies, and by phenylhydrazine-modification experiments. The binding interaction for the cyanide-bound derivative (APX-CN) is consistent with a 1:1 stoichiometry and is characterised by an equilibrium dissociation binding constant. Kd, of 11.6 +/- 0.4 microM (pH 7.002, mu = 0.10 M, 25.0 degrees C). Individual distances between the non-exchangeable substrate protons of APX-CN and the haem iron were determined by paramagnetic-relaxation NMR measurements, and the data indicate that the ascorbate binds 0.90-1.12 nm from the haem iron. The reaction of ferric APX with the suicide substrate phenylhydrazine yields predominantly (60%) a covalent haem adduct which is modified at the C20 carbon, indicating that substrate binding and oxidation is close to the exposed C20 position of the haem, as observed for other classical peroxidases. Molecular-modelling studies, using the NNM-derived distance restraints in conjunction with the crystal structure of the enzyme [Patterson, W. R. & Poulos, T. L. (1995) Biochemistry 34, 4331-4341], are consistent with binding of the substrate close to the C20 position and a possible functional role for alanine 134 (proline in other class-III peroxidases) is implicated.     

Correlation of thallium uptake with left ventricular wall thickness by cine magnetic resonance imaging in patients with acute and healed myocardial infarcts

Myocardial infarction (MI) is characterized by cellular necrosis which undergoes fibrotic transformation over time. Cine magnetic resonance imaging (MRI) offers high-resolution 3-dimensional images of the left ventricular myocardium, allowing sampling of the myocardial wall thickness over the entire left ventricle. Tomographic (single-photon emission computed tomography [SPECT]) thallium images also provide 3-dimensional information on the location and level of thallium uptake, which has been shown to correlate with myocardial viability. The purposes of this study were: (1) to examine the relation between both end-diastolic and end-systolic wall thickness and normalized thallium-201 uptake over the left ventricle in a group of patients with MI, (2) to examine the relation between regional wall thickening and normalized thallium uptake, and (3) to examine the relation between thallium uptake and wall thickness both early and late after infarction. Twenty-four patients with MI underwent stress, redistribution, and reinjection thallium SPECT imaging and cine MRI within several days. Seventeen patients underwent imaging late after infarction and 7 underwent imaging early after infarction. Normalized thallium activity was correlated with MRI wall thicknesses at both end-diastole and end-systole for 18 segments for each ventricle. In addition, end-diastolic and end-systolic wall thicknesses were grouped by their corresponding thallium activity levels into percentiles. End-systolic wall thickness correlated significantly with normalized thallium uptake in 14 of 18 segments, end-diastolic wall thickness in only 4 of 18 segments, and wall thickening in only 3 of 18 segments. Mean values for end-diastolic and end-systolic wall thicknesses corresponding to severely reduced (<50%) normalized thallium activity were 9.9 +/- 1.1 and 8.5 +/- 0.6, respectively. Using receiver-operating curve analysis, end-systolic wall performed as a better diagnostic parameter than end-diastolic wall for identifying severely reduced thallium activity levels. For all levels of thallium activity, end-diastolic wall thicknesses were all thinner late versus early after MI, whereas end-systolic wall thickness was thinner only in the segments corresponding to severely reduced thallium activity. Based on these results, end-systolic wall thickness is the best noninvasive anatomic parameter of myocardial scar.     

Treatment of agitation in dementia

Agitation occurs commonly in patients with dementia. Before symptomatic pharmacotherapy is undertaken, it is imperative to perform a sequence of evaluations and interventions to establish whether simpler and safer, nonpharmacologic approaches will be beneficial. When psychotropic medications are used they should be used judiciously, in the lowest effective doses and for the shortest period of time necessary. Ineffective medications should be stopped, and even effective medications should be empirically tapered in most patients to learn whether treatment is still necessary. Antipsychotics probably show the greatest benefit for agitation associated with psychotic features; they have less demonstrated efficacy for agitation not associated with psychotic features. The side effects of typical agents are legion; data are pending regarding atypical agents. The available evidence regarding nonneuroleptic medications ranges from case reports to well-designed, double-blind, placebo-controlled, randomized, parallel group studies. Literature exists describing the use of anticonvulsants, anxiolytics, serotonergic antidepressants, and other agents to manage agitation. Carbamazepine and divalproex sodium (valproate) have demonstrated efficacy in uncontrolled studies, whereas the use of carbamazepine has produced negative results in one small controlled study and positive results in two larger controlled studies. Buspirone has shown benefit in some open trials. Encouraging early findings have been reported for trazodone, including from one controlled trial. Varying results have been obtained using selective serotonin reuptake inhibitors, but with consistently encouraging anecdotes. In the aggregate, the evidence suggests but does not prove that alternatives to traditional antipsychotics exist. Again, none of these agents has yet been approved for this purpose by the FDA. As more studies become available we will have a better idea about which classes of agents are most efficacious. It is likely that there may be a role for "rational" polypharmacy in the management of this distressing complication of dementia. However, no studies that we know of address combination therapy, so the clinician must contemplate this option on a case-by-case basis. Clinical trials data are pending from studies with divalproex sodium, carbamazepine, haloperidol versus trazodone versus placebo, risperidone, olanzapine, quetiapine, donepezil, xanomeline, tacrine, buspirone, and sertraline, at the very least. These data will undoubtedly have a major impact on how we care for our patients and lead to revisions of current practice guidelines.     

Bradykinin antagonists in human systems: correlation between receptor binding, calcium signalling in isolated cells, and functional activity in isolated ileum

The determination of the relationship between ligand affinity and bioactivity is important for the understanding of receptor function in biological systems and for drug development. Several physiological and pathophysiological functions of bradykinin (BK) are mediated via the B2 receptor. In this study, we have examined the relationship between B2 receptor (soluble and membrane-bound) binding of BK peptidic antagonists, inhibition of calcium signalling at a cellular level, and in vitro inhibition of ileum contraction. Only human systems were employed in the experiments. Good correlations between the studied activities of BK antagonists were observed for a variety of different peptidic structures. The correlation coefficients (r) were in the range of 0.905 to 0.955. In addition, we analyzed the effect of the C-terminal Arg9 removal from BK and its analogs on B2 receptor binding. The ratios of binding constants (Ki(+Arg)/Ki(-Arg)) for the Arg9 containing compounds and the corresponding des-Arg9 analogs varied from about 10 to 250,000. These ratios strongly depend on the chemical structures of the compounds. The highest ratios were observed for two natural agonist pairs, BK/des-Arg9-BK and Lys0-BK/des-Arg9-Lys0-BK.     

Responsive gels formed by the spontaneous self-assembly of peptides into polymeric beta-sheet tapes

Molecular self-assembly is becoming an increasingly popular route to new supramolecular structures and molecular materials. The inspiration for such structures is commonly derived from self-assembling systems in biology. Here we show that a biological motif, the peptide beta-sheet, can be exploited in designed oligopeptides that self-assemble into polymeric tapes and with potentially useful mechanical properties. We describe the construction of oligopeptides, rationally designed or based on segments of native proteins, that aggregate in suitable solvents into long, semi-flexible beta-sheet tapes. These become entangled even at low volume fractions to form gels whose viscoelastic properties can be controlled by chemical (pH) or physical (shear) influences. We suggest that it should be possible to engineer a wide range of properties in these gels by appropriate choice of the peptide primary structure.     

Coping behaviors of the elderly with positive physical examination results in Kaohsiung City

The objectives of this study were as follows: first, to investigate the coping behaviors of the elderly facing the stress of disease after free physical examination; Second, to identify personal and disease characteristics, and the social support that influences coping behaviors in the elderly. The study sample consisted of 661 elderly patients who were found to have abnormal findings during a free physical examination provided by 11 regional health stations in Kaohsiung City. Data were collected with questionnaires through home interview. Four hundred and eighty-four subjects completed the questionnaires. Data were analyzed using SAS computer program. The major findings were as follows: 1.Problem-oriented coping behaviors were the more frequently used. The most frequently used coping behaviors were "accepting the situation as it is", "reling on myself to solve problems", "hoping that things would get better", "seeking professional help", and "letting things follow their natural cause". 2. The relative variables for problem-oriented coping were marital status, religion, medical insurance, educational level, disease characteristics, and social support. Sex, marital status, religion, medical insurance, perceived disease severity, characteristics of health problem, and newly found abnormality at this free physical examination were the relative variables for affective-oriented coping. 3. The best predictive variables for using problem-oriented coping behaviors were medical insurance, self-esteem support from family and friends, tangible support from health professionals, emotional support from health professionals, and whether it was the first time the patients knew their health problems. Findings from this study had implications for development of nursing care plans for elderly clients, as well as for collaborative team exploration of coping behaviors in the elderly.     

Mortality determinants in massive pediatric burns. An analysis of 103 children with > or = 80% TBSA burns (> or = 70% full-thickness)

OBJECTIVE: Survivors and nonsurvivors among 103 consecutive pediatric patients with massive burns were compared in an effort to define the predictors of mortality in massively burned children. SUMMARY BACKGROUND DATA: Predictors of mortality in burns that are used commonly are age, burn size, and inhalation injury. In the past, burns over 80% of the body surface area that are mostly full-thickness often were considered fatal, especially in children and in the elderly. In the past 15 years, advances in burn treatment have increased rates of survival in those patients treated at specialized burn centers. The purpose of this study was to document the extent of improvement and to define the current predictors of mortality to further focus burn care. METHODS: Beginning in 1982, 103 children ages 6 months to 17 years with burns covering at least 80% of the body surface (70% full-thickness), were treated in the authors' institution by early excision and grafting and have been observed to determine outcome. The authors divided collected independent variables from the time of injury into temporally related groups and analyzed the data sequentially and cumulatively through univariate statistics and through pooled, cross-sectional multivariate logistic regression to determine which variables predict the probability of mortality. RESULTS: The mortality rate for this series of massively burned children was 33%. Lower age, larger burn size, presence of inhalation injury, delayed intravenous access, lower admission hematocrit, lower base deficit on admission, higher serum osmolarity at arrival to the authors' hospital, sepsis, inotropic support requirement, platelet count < 20,000, and ventilator dependency during the hospital course significantly predict increased mortality. CONCLUSIONS: The authors conclude that mortality has decreased in massively burned children to the extent that nearly all patients should be considered as candidates for survival, regardless of age, burn size, presence of inhalation injury, delay in resuscitation, or laboratory values on initial presentation. During the course of hospitalization, the development of sepsis and multiorgan failure is a harbinger of poor outcome, but the authors have encountered futile cases only rarely. The authors found that those patients who are most apt to die are the very young, those with limited donor sites, those who have inhalation injury, those with delays in resuscitation, and those with burn-associated sepsis or multiorgan failure.     

Roentgen stereophotogrammetric analysis using computer-based image-analysis

The two-dimensional position of markers in radiographs for Roentgen Stereophotogrammetric Analysis (RSA) is usually determined using a measuring table. The purpose of this study was to evaluate the reproducibility and the accuracy of a new RSA system using digitized radiographs and image-processing algorithms to determine the marker position in the radiographs. Four double-RSA examinations of a phantom and 18 RSA examinations from six patients included in different RSA-studies of knee prostheses were used to test the reproducibility and the accuracy of the system. The radiographs were scanned at 600 dpi resolution and 256 gray levels. The center of each of the tantalum-markers in the radiographs was calculated by the computer program from the contour of the marker with the use of an edge-detection software algorithm after the marker was identified on a PC monitor. The study showed that computer-based image analysis can be used in RSA-examinations. The advantages of using image-processing software in RSA are that the marker positions are determined in an objective manner, and that there is no need for a systematic manual identification of all the markers on the radiograph before the actual measurement.