Kaposi's sarcoma (author's transl)

Kaposi's sarcoma of the skin and an aplastic syndrome occurred together in a 51-year-old patient. Macroscopically livid papules and nodules were observed. Histomorphologically endotheliomatous cell proliferation with signs of infiltrative growth was found. Because of the aplastic pancytopenia cytostatic treatment of the Kaposi sarcoma was contraindicated. The patient finally died of vascular failure with haemorrhagic diathesis being manifest. Syntropy of Kaposi's sarcoma with malignant haematological diseases is known. However, association with aplastic anaemia has not been observed so far. The pathogenesis of Kaposi's sarcoma is unknown.     

Analysis of the systemic corticosteroid sensitivity of patients with primary open-angle glaucoma

Patients with primary open-angle glaucoma have an ocular and systemic sensitivity to corticosteroids. We adapted a cellular assay that used peripheral blood lymphocytes to detect this corticosteroid sensitivity in vitro in a microtiter assay. It reduced the time, cost, and amount of blood required to examine a patient. We examined ten subjects on three separate days and demonstrated that the reliability of one 50% inhibitory concentration was about 76%. We then studied 25 patients with primary open-angle glaucoma and 25 control subjects using this in vitro assay. The patients with primary open-angle glaucoma were significantly more sensitive to corticosteroids than the control subjects (P less than .001).     

Association of leptin and hunger-satiety ratings in obese women

OBJECTIVE: To measure leptin, insulin and cholecystokinin (CCK) concentrations in obese women on calorie restriction and to determine their correlation with hunger-satiety ratings. Although it has been proposed to play a role in appetite regulation, the effects of physiological concentrations of these hormones on hunger-satiety in humans have not yet been well established. DESIGN: Prospective metabolic study. A two week 'wash-in period' followed by a three-week observation period, during which each subject underwent six measurements of satiety, blood parameters and body weight. SETTING: Energy Metabolism Research Unit, Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA. SUBJECTS: 22 moderately to severely overweight women (mean age: 45 +/- 8 y; body mass index (BMI): 33 +/- 6 kg/m2). INTERVENTION: Energy restriction, in the form of a 3.3 MJ (800 kcal) diet during five weeks. MAIN OUTCOME MEASUREMENTS: Fasting blood levels of leptin, insulin, glucose and CCK, fasting hunger-satiety scores and body weight. RESULTS: The mean (+/- s.d.) fasting serum leptin concentration at the beginning of the observation period was 26.1 +/- 15.9 ng/ml (range: 6.7-59.8 ng/ml). Leptin concentrations correlated positively with body weight (P < 0.0001). Furthermore, reductions in body weight were associated with decreases in fasting leptin levels (P = 0.002). Leptin concentrations correlated with serum levels of insulin (P = 0.0001) and CCK (P = 0.06), but in multivariate analysis including insulin, CCK and glucose, only leptin had a significant relationship with satiety (P = 0.04). This relationship was linear. CONCLUSIONS: These results confirm the association between leptin levels, body weight and serum insulin. We also showed that higher serum leptin levels correlated with greater feelings of fullness, a relationship which was not blunted in the more obese subjects. These findings suggest that leptin is a satiety hormone that reduces appetite, even in obese individuals, and that weight gain must be due to other factors, overriding this feed-back regulation.     

Incidence and outcome of Staphylococcus aureus bacteremia in hemodialysis patients

BACKGROUND: Staphylococcus aureus bacteremia is frequently associated with metastatic complications and infective endocarditis (IE). The Duke criteria for the diagnosis of IE utilize echocardiographic techniques and are more sensitive than previous criteria. The documentation of IE in patients undergoing hemodialysis (HD) has become increasingly important in order to avoid the overuse of empiric vancomycin and the emergence of antibiotic resistance. METHODS: Patients who developed S. aureus bacteremia while undergoing HD at a tertiary medical center or one of four affiliated outpatient HD units were identified. Clinical outcome (death, metastatic complications, IE, and microbiologic recurrence) was assessed during hospitalization and at three months after discharge. Transthoracic and transesophageal echocardiograms were performed and the Duke criteria were used to diagnose IE. Pulse field gel electrophoresis was performed to confirm genetic similarity of recurrent isolates. RESULTS: Four hundred and forty-five patients underwent hemodialysis for 5431.8 patient-months. Sixty-two developed 65 episodes of S. aureus bacteremia (1.2 episodes/100 patient-months). Complications occurred in 27 (44%) patients. Bacteremia recurred in patients who dialyzed through polytetrafluorethylene grafts (44.4% vs. 7.1%, P = 0.0.01), and there was a trend to increased recurrence in patients who received only vancomycin (19.5% vs. 7.1%, P = 0.4). IE was diagnosed in 8 patients (12%), six of whom had normal transthoracic echocardiograms. CONCLUSIONS: Sensitive echocardiographic techniques and the Duke criteria for the diagnosis of IE should be used to determine the proper duration of antibiotic therapy in hemodialysis patients with S. aureus bacteremia. This diagnostic approach, coupled with early removal of hardware, may assist in improving outcomes.     

Optimal robust classifiers

Qualitatively, a filter is said to be “robust” if its performance degradation is acceptable for distributions close to the one for which it is optimal, that is, the one for which it has been designed. This paper adapts the signal-processing theory of optimal robust filters to classifiers. The distribution (class conditional distributions) to which the classifier is to be applied is parameterized by a state vector and the principle issue is to choose a design state that is optimal in comparison to all other states relative to some measure of robustness. A minimax robust classifier is one whose worst performance over all states is better than the worst performances of the other classifiers (defined at the other states). A Bayesian robust classifier is one whose expected performance is better than the expected performances of the other classifiers. The state corresponding to the Bayesian robust classifier is called the maximally robust state. Minimax robust classifiers tend to give too much weight to states for which classification is very difficult and therefore our effort is focused on Bayesian robust classifiers. Whereas the signal-processing theory of robust filtering concentrates on design with full distributional knowledge and a fixed number of observation variables (features), design via training from sample data and feature selection are so important for classification that robustness optimality must be considered from these perspectives—in particular, for small samples. In this context, for a given sample size, we will be concerned with the maximally robust state-feature pair. All definitions are independent of the classification rule; however, applications are only considered for linear and quadratic discriminant analysis, for which there are parametric forms for the optimal discriminants.     

Cytokines and the microcirculation in ischemia and reperfusion

The intense inflammatory reaction following reperfusion of the infarcted myocardium has been implicated as a factor in extension of injury. However, this inflammatory reaction is also critical to tissue repair. The cellular responses that mediate these functions are orchestrated by sequential induction and/or release of cytokines resulting in a closely regulated cytokine cascade. This paper reviews research on these cytokine cascades, their cellular origin, and factors which control the cellular response to their presence. Factors examined include leukotaxis, phenotypic transition of leukocytes, adhesion molecule induction and the role of cytokines in tissue repair and scar formation.     

Human T- and B-cell reactivity to the 16kDa alpha-crystallin protein of Mycobacterium tuberculosis

PURPOSE: To determine whether inflammatory corneal neovascularization (CNV) is associated with interleukin-1 (IL-1) activity and if so, to assess the efficacy of topical interleukin-1 receptor antagonist (IL-1ra) to suppress CNV. METHODS: Inflammatory CNV was induced on day 0 by placement of paracentral intrastromal sutures in BALB/c murine eyes. Quantification of IL-1alpha and -beta cytokine levels was done by a sandwich enzyme-linked immunosorbent assay (ELISA) on the supernatants of incubated corneas excised at specified time points after induction of CNV (n = 6 per time point studied). To study suppression of CNV by IL-1ra, animals were divided into treatment subgroups that received topical 20 mg/ml of IL-1ra mixed in 0.2% sodium hyaluronate (n = 28) or placebo (vehicle) alone (n = 22) 3 times daily during days 0-35. Other groups of animals received placebo for 1 (n = 10) or 2 (n = 14) weeks before being switched and retained on IL-1ra. Neovascularization was assessed biomicroscopically and graded by using a standardized scheme. RESULTS: Induction of CNV stimulus was associated with a significant surge in the expression of both IL-1alpha (p < 0.001) and IL-1beta (p < 0.001) as early as 2 h after the stimulus, which peaked at 24 h, before decreasing substantially in the case of IL-1beta and returning to basal levels by day 7. Topical application of IL-1ra led to a significant suppression of CNV for the duration of therapy only if initiated early after induction of the neovascular stimulus. Initiation of therapy 1 week after CNV induction was associated only with a transient suppression in the angiogenic response. CONCLUSION: Our data strongly implicate IL-1 as a critical mediator in the early phase of CNV and suggest that IL-1ra can be an effective modality in suppressing CNV if initiated sufficiently early after the inflammatory neovascular stimulus.     

Benchmarking the perioperative process: III. Effects of regional anesthesia clinical pathway techniques on process efficiency and recovery profiles in ambulatory orthopedic surgery

STUDY OBJECTIVES: (1) To incorporate regional anesthesia options for common outpatient orthopedic surgery into clinical pathways; (2) to use the clinical pathway format and the Procedural Times Glossary published by the Association of Anesthesia Clinical Directors (AACD) as management tools to measure postoperative same-day surgery processes and discharge outcomes; and (3) to determine the effects of general, regional, and combined general-regional anesthesia on these processes and outcomes. DESIGN: Hospital database and patient chart review of consecutive patients undergoing anterior cruciate ligament reconstruction (ACLR) during academic years (AY) 1995-1996 and 1996-1997. Patient data from AY 1995-1996, during which no intraoperative anesthesia clinical pathway existed, served as historical controls. Data from AY 1996-1997, during which intraoperative anesthesia clinical pathways were used, served as the treatment group. SETTING: Ambulatory surgery center in a teaching hospital. MEASUREMENTS AND MAIN RESULTS: The records of 503 ASA physical status I and II patients were reviewed. 1996-1997 patients selected general anesthesia (+/- femoral nerve block) or epidural anesthesia, after which the remainder of the perioperative anesthesia process was standardized with respect to the drugs and equipment used. 1995-1996 patients did not necessarily have a choice in anesthesia technique and did not have a standardized perioperative anesthetic course with respect to specific drugs and supplies. Intervals described in the AACD Procedural Times Glossary, anesthesia drug and supply costs, and patient outcome variables (postoperative nursing interventions required and unexpected admissions), as influenced by anesthesia technique used, were measured. Combined general-regional anesthesia care for ACLR in 1996-1997, when compared with general anesthesia alone, led to increased pharmacy and materials costs and increased turnover time. However, patients with the combined technique showed improved recovery profiles and lower unexpected admission rates, and they required fewer nursing interventions for common postoperative symptoms. Patients receiving epidural anesthesia showed discharge outcomes similar to those patients receiving general anesthesia with femoral nerve block. Postanesthesia care unit bypass (fast-tracking) was more likely in clinical pathway regional anesthesia patients, when compared with the clinical pathway general anesthesia used. CONCLUSIONS: Clinical pathway regional anesthesia care for outpatient orthopedics may have a significant role in simultaneously containing costs and improving both process efficiency and patient outcomes.