Predictors of perceived health status in elderly men and women. The Cardiovascular Health Study

Baseline data on the perceived health status of participants (N = 5,201) in the Cardiovascular Health Study of the Elderly (CHS) are reported. The authors examined the predictive utility of health-related factors representing eight different domains, assessed gender differences in the prediction of perceived health, and tested a hypothesis regarding the role of known clinical conditions versus subclinical disease in predicting perceived health. Multivariate analyses showed that the majority of the explained variance in self-assessed health is accounted for by variables that fall into four general categories. Although gender differences were small, the analysis showed that the relative importance of several predictor variables did vary by gender.     

Frozen red blood cells in combat casualty care: clinical and logistical considerations

OBJECTIVE: To test the hypothesis that a supply of frozen red blood cells and a system for processing pyrogen-free crystalloid solution would meet the needs of an echelon 3 medical treatment facility in the U.S. military, caring for casualties during the initial phase of a military medical operation. DATA SOURCES: Blood requirements for potential combat casualties were estimated from transfusion data on: (1) patients admitted to Boston City Hospital following trauma, utilizing a computerized data base, (2) patients admitted to the Naval Support Hospital-Da Nang during the Vietnam War, from 1966 to 1970, from published and unpublished material, and (3) casualties estimated by Department of Defense expert panels for specific conflicts. The procedure for processing frozen red blood cells was evaluated at the Naval Blood Research Laboratory. Estimates of wounded in action were provided by the Department of Defense. DATA SYNTHESIS: Computer modeling using standard spreadsheet software on a personal computer. CONCLUSIONS: Under military conditions, a frozen red blood cell bank and a system for processing pyrogen-free resuscitative fluid could be used to prepare 96 units of red cells and 960 1 of crystalloid solution per day. This would be adequate to treat approximately 180 casualties, the number projected for a 5-day battle with heavy casualties (6 wounded in action/1,000 soldiers/day). It was concluded that a frozen blood bank system and system for processing pyrogen-free resuscitative fluid could successfully meet the needs of an echelon 3 medical facility in the initial phase of a military medical operation.     

Clinical significance of technetium-99m methylene diphosphonate myocardial uptake: association with carcinoma of the prostate

Benign myocardial uptake of technetium-99m labelled phosphates, not related to cardiac or metabolic disorders, has been documented except in the case of^99mTc-methylene diphosphonate (MDP). The aim of this study was to assess the frequency of myocardial uptake and its possible association with malignant tumours in general and prostatic carcinoma in particular. We reviewed bone scintigrams performed with either^99mTc-hydroxydiphosphonate (HDP) or^99mTc-MDP over a period of more than 2 years for all patients with prostatic carcinoma and a matching group of patients suffering from other malignant and non-malignant disorders. A total of 965 scintigrams of 812 patients (males=559, females=253; age range 50–91 years, average age 69.2 years) were reviewed. Increased myocardial uptake was detected in 19 scintigrams (MDP=13, HDP=6) of 18 patients (17 males, one female). Most of the male patients with increased myocardial uptake had prostatic carcinoma (13/17) and were over 80 years of age (12/17). All patients were free of any cardiac or noncardiac disorder that might account for such uptake. When scintigraphy was repeated in the same patient, the uptake of^99mTc-HDP was more diffuse and of higher grade than that of^99mTc-MDP Benign myocardial uptake of^99mTc-MDP is more common than previously thought. Although uptake of radiophosphates is attributed to asymptomatic atherosclerotic changes associated with old age, a strong association with prostatic carcinoma exists which may indicate variations in the bone: soft tissue affinity of different MDP complexes.     

Analysing ion channels with hidden Markov models

Ion channel current amplitudes () and open probabilities (P _o) have been analysed so far by defining a 50% threshold to distinguish between open and closed states of the channels. With this standard method (SM) it is very difficult or even impossible to analyse channels of different size in one membrane patch correctly. A stochastical model, named the hidden Markov model (HMM), separates between observation noise and the stochastic process of opening and closing of ion channels. The HMM allows the independent analysis of , P _o, and mean dwell times () of different channels in one membrane patch, without defining threshold levels. Using this method errors in the analysis are not summarized like in the SM because all different analysing procedures (e. g. filtering, setting of threshold, fitting processes) are done in one step. Two different K⁺ channels in excised basolateral membranes of the cortical collecting duct of rat (CCD) were analysed by the SM and the HMM. The value of the intermediate-conductance K⁺ channel (i-K⁺) was 3.9±0.1 pA (SM) and 3.8±0.2 pA (HMM) for 11 observations. The P _o value of this channel was 10.2±4.2% (SM) and 10.1±4.0% (HMM). The mean values were 5.4±0.6 ms for the open state and 9.6±2.2 ms and 145±21 ms for the closed states (SM) and 7.8±1.1 ms, 7.7±0.9 ms and 148±24 ms (HMM), respectively. For seven small-conductance K⁺ (s-K⁺) channels, which were found in the same membrane patches as the i-K⁺, an accurate analysis of P _o and was not possible with the SM. The value was 1.0±0.1 (SM), 0.9±0.1 (HMM) pA. P _o was 16.6±4.6%, the open value was 11.1±2.8 ms, and the closed value was 34.9±8.5 ms. The HMM allows the analysis of single-channel currents, P _o, and mean values when different or more than one ion channel(s) are colocalized in one membrane patch. Where analysis with the SM was possible results did not significantly differ from those obtained with the HMM. Thus for this kind of analysis the method of setting a 50% threshold appears justified.     

Surgery of epilepsy associated with focal lesions in childhood

OBJECT: Surgery in children with epilepsy is a new, evolving field. The important practical issues have been to define strategies for choosing the most suitable candidates and the type and optimal timing of epilepsy surgery. This study was undertaken to elucidate these points. METHODS: To identify the factors that correlated with outcome, the authors analyzed a series of 200 children (aged 1-15 years (mean 8.7 years) who underwent surgery between 1981 and 1996 at the H?pital Necker-Enfants Malades. In 171 cases (85.5%) the epilepsy was medically refractory and was associated with focal cortical lesions. Surgery consisted of resection of the lesion without specifically attempting to identify and remove the "epileptogenic area. "In the group of children whose seizures were medically refractory, the mean follow-up period was 5.8 years. According to Engel's classification, 71.3% of these children became seizure free (Class 1a,) whereas 82% were in Class I. A multivariate statistical analysis revealed that among all the factors studied, the success of surgery in a patient in whom there was a good clinical/electroencephalogram/imaging correlation depended on the patient's having undergone a minimally traumatic operation, a complete resection of the lesion, and a short preoperative seizure duration. After the surgical control of epilepsy, behavior disorders were more improved (31% of all patients) than cognitive function (25%). The patient age at onset, duration and frequency of seizures, intractability of the disease to therapy, and seizure characteristics were correlated with cognitive, behavioral, and academic performance pre- and postoperatively. Multivariate statistical analysis revealed that cognitive dysfunction correlated highly with the duration of epilepsy prior to surgery, whereas behavioral disorders correlated more with seizure frequency. CONCLUSIONS: These data must be taken into account when selecting patients for surgical treatment and when deciding the timing of surgery. Early surgical intervention allows for optimum brain development.     

Effect of pulse pressure on vascular smooth muscle cell migration: the role of urokinase and matrix metalloproteinase

Plasminogen activator (PA) expression plays an important role in smooth muscle cell (SMC) migration and may therefore contribute to mechanical force-induced arterialization of vein grafts. The aim of this study was to determine whether pulse pressure due to pulsatile flow modulates SMC migration via urokinase (u-PA)-dependent mechanisms. Using a perfused transcapillary culture system, human umbilical vein SMC were exposed to pulse pressures (0-56 mmHg), in the absence or presence of human umbilical vein endothelial cells (EC) by varying pulsatile flow rates (0 ml/min to 25 ml/min). SMC cultured in the absence of EC increased their migration following exposure to increased pulse pressure (248+/-14%). Both u-PA and matrix metallo-proteinase 1 (MMP-1) expression was significantly elevated in SMC exposed to pressure as compared to static controls. The role of proteases in the pulse pressure-induced enhancement of SMC migration was confirmed following pretreatment with aprotinin, an anti u-PA antibody and metalloproteinase inhibitors (181+/-14% for aprotinin vs. 256+/-25% for control, 108+/-4% for anti-u-PA antibody vs. 233+/-17% for non-immune IgG, and 114+/-9% for BB-94, 105+/-7% for BB-3103 vs. 222+/-5% for control). Using SMC derived from u-PA gene knock-out mice, the SMC migratory response to increased pulse pressure was completely inhibited despite a significant increase in MMP expression in these cells. These results suggest that pulse pressure due to pulsatile flow induces SMC migration in vitro via u-PA and MMP-dependent mechanisms. Moreover, u-PA gene deletion results in blunting of pressure-induced SMC migration despite the endogenous upregulation of metalloproteinase. Modulation of u-PA expression by pressure may thus represent an important mechanism whereby hemodynamic forces regulate smooth muscle cell migration.     

Cognitive development in benign focal epilepsies of childhood

Benign focal epilepsy of childhood (BFEC) is the most common form of epilepsy, in children from 3 to 12 years. Its prognosis is always favourable as far as the epilepsy is concerned. Nevertheless, recent clinical data suggest that children affected by BFEC are more likely to show learning difficulties and behavioural disturbances than their peers. We report here the preliminary findings of a prospective study of 22 children affected with BFEC. Electroclinical and neuropsychological changes observed during the first 18 months of the follow-up strengthen the conclusion of recent neuropsychological studies stressing the correlation between epilepsy and cognitive performances. The cognitive deficits affecting mainly non-verbal functions were significantly correlated with the frequency of seizures and spike-wave discharges and to the lateralization of the epileptic focus in the right hemisphere, whereas frontal functions like attention control, response organization and fine motor speed, were impaired in the presence of active BFEC independently of the lateralization of the epileptic focus. Our results indicate that maturing cognitive functions subserved by a cortical area distant from the epileptic focus are susceptible to interference with epilepsy. Copyright Copyright 1999 S. Karger AG, Basel     

Medicare managed care and the need for quality measurement

With the increasing penetration of managed care as health insurance coverage for Medicare beneficiaries, accountability for quality of care is being demanded. While HEDIS 2.5 has become the standard for assessing the performance of health plans in caring for their commercial members, no such standard exists for Medicare enrollees. U.S. Quality Algorithms, the performance measurement subsidiary of U.S. Healthcare, has developed the Medicare Quality Report Card as a tool for performance assessment and quality improvement. This article describes how the measures of quality important to the Medicare population were chosen, how the measures were calculated, and how they have been used in programs designed to improve the quality of care for U.S. Healthcare Medicare members.     

Hydroxyapatite cement to repair skull base defects: radiologic appearance.

PURPOSETo describe the radiologic appearance of hydroxyapatite cement (HAC), which, when mixed with liquid, forms a paste that can be contoured to osseous defects and, over time, becomes "osseointegrated" (native bone grows into the pores of the HAC and forms a strong chemical bond with the substance).METHODSBetween March 1992 and June 1993, 24 adults (16 men, eight women) underwent skull base surgery that included reconstruction or closure with HAC. Fourteen patients had HAC placed in the paranasal sinuses or facial bones, and 10 had HAC placed in the mastoid cavity.RESULTSHAC is homogeneously radiopaque on CT scans and plain radiographs. Large amounts (ablating a frontal sinus or mastoid air cells) are readily seen; small amounts are inconspicuous. On MR images, HAC is a signal void. Infected HAC in one patient was surrounded be enhancing soft tissue on MR images, separated from native bone by an irregular radiolucent cleft on CT scans.CONCLUSIONSHAC is a valuable addition to the surgical armamentarium for the repair of skull base defects. More experience will determine the time course for normal osseointegration, as well as the typical appearance of infection.