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OBJECTIVE: Infection and thrombosis are important complications of intravascular catheters. The purpose of this study was to determine the incidence of thrombosis in patients with central venous catheter-associated Staphylococcus aureus bacteremia and the utility of physical examination for diagnosing upper extremity or neck venous thrombosis. DESIGN: Prospective observational cohort. SETTING: Tertiary care facility. PATIENTS: In all, 65 consecutive patients with catheter-associated S. aureus bacteremia with central venous catheters of the internal jugular, brachial, or subclavian veins were eligible for participation. INTERVENTION: From July 1999 through August 2004, enrolled patients underwent physical examination and ultrasonography independently to identify the presence of catheter-associated thrombosis. Study ultrasonograms were interpreted blindly using defined criteria. Outcomes were defined at 12-wk follow-up. MEASUREMENTS AND MAIN RESULTS: A total of 48 patients were enrolled. By ultrasonography, definite or possible thrombosis was present in 34 of 48 patients (71%) in this cohort. Death or recurrent bacteremia occurred in 11/34 (32%) infected patients with thrombosis and two of 14 (14%) infected patients without thrombosis (p = .29). Sensitivity of all physical examination findings, either alone or in combination, was low (< or = 24%). Only engorged veins upon hand elevation and the presence of multiple physical examination abnormalities were specific (100% each). CONCLUSIONS: Thrombosis is a common complication of central venous catheter-associated S. aureus bacteremia. Patients with central venous catheter-associated S. aureus bacteremia should undergo ultrasonography to detect thromboses even if the physical examination is normal. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the concentration of transforming growth factor beta 1 (TGFB1) levels in a rat pleural effusion obtained by inoculation of intrapleural bacteria or turpentine through thoracentesis., Methods: Thirty-Nine Wistar rats were divided into three groups: Staphylococcus aureus (SA, n = 17); Streptococcus pneumoniae (SP, n = 12); and turpentine (control, n = 10). Pleural fluid was collected through ultrasound-guided thoracentesis 12 h, 24 h, and 36 h after instillation of bacteria or turpentine. Levels of TGFB1 were measured in pleural fluid., Results: At 12 h, mean TGFB1concentrations were 5.3450 pg/mL in the SA group, 5.3449 pg/mL in the SP group, and 5.3450 pg/mL in controls. At 24 h, they were 4.6700 pg/mL in the SA group, 4.6700 pg/mL in the SP group, and 4.6700 pg/mL in controls. At 36 h, they were 4.6699 pg/mL in the SA group and in control. No difference was observed among the groups in mean TGFB1concentration (p = 0.12); however, a significant intragroup reduction in mean TGFB1 was observed between 12 and 24 h (p < 0.01)., Conclusion: The transforming growth factor beta 1 concentrations were not useful as a diagnostic tool or an early marker of infected pleural effusion.

Background: Pleural empyema is a well-known complication of pneumonia. If treatment is delayed, empyema may increase morbidity and mortality in affected patients. Therefore, the identification of empyema biomarkers in parapneumonic pleural effusion is desirable. Previous research has suggested complement activation products as candidate empyema markers., Objective: To compare the levels of complement activation products C3a, C5a, and C5b9 in pleural effusion induced by Staphylococcus aureus (SA), Streptococcus pneumoniae (SP), or turpentine (control)., Methods: Thirty-nine male Wistar rats (mean weight 414 g; 290-546 g) were allocated as follows: 17 animals in the SA group, 12 in the SP group, and 10 in the control group. Bacteria or turpentine were injected into the pleural space. After 12 hr, intrapleural fluid was collected using ultrasound-guided thoracentesis. Levels of complement activation products were determined using ELISA kits., Results: Two SA and one SP animals died before 12 hr. Mean levels were as follows: C3a: 1066.82 µg/ml (937.29-1196.35 µg/ml) in SA, 1188.28 µg/ml (1095.65-1280.92 µg/ml) in SP, and 679.13 µg/ml (601.29-756.98 µg/ml) in controls (P < 0.001); C5a: 55.727 ng/ml (41.22-70.23 ng/ml) in SA, 520.107 ng/ml (278.92-761.3 ng/ml) in SP, and 5.268 ng/ml (1.68-8.85 ng/ml) in controls (P < 0.001); C5b9: 15.02 ng/ml (13.1-16.94 ng/ml) in SA, 16.63 ng/ml (14.37-18.9 ng/ml) in SP, and 14.05 ng/ml (9.8-18.29 ng/ml) in controls (P = 0.692). ROC analysis revealed an area under the curve of 0.987 (95% CI: 0.953-1) for C3a; 1 (1-1) for C5a; and 0.757 for C5b9 (0.523-0.990)., Conclusions: In the present rat model, complement activation fragments C3a and C5a accurately detected infected pleural effusion. Pediatr Pulmonol. 2017;52:757-762. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Objective: The purpose of this study was to compare the effects of 3 different exercise approaches on neck muscle endurance (NME), kinesiophobia, exercise compliance, and patient satisfaction in patients with chronic whiplash., Methods: This prospective randomized clinical trial included 216 individuals with chronic whiplash. Participants were randomized to 1 of 3 exercise interventions: neck-specific exercise (NSE), NSE combined with a behavioral approach (NSEB), or prescribed physical activity (PPA). Measures of ventral and dorsal NME (endurance time in seconds), perceived pain after NME testing, kinesiophobia, exercise compliance, and patient satisfaction were recorded at baseline and at the 3- and 6-month follow-ups., Results: Compared with individuals in the prescribed physical activity group, participants in the NSE and NSEB groups exhibited greater gains in dorsal NME (P = .003), greater reductions in pain after NME testing (P = .03), and more satisfaction with treatment (P < .001). Kinesiophobia and exercise compliance did not significantly differ between groups (P > .07)., Conclusion: Among patients with chronic whiplash, a neck-specific exercise intervention (with or without a behavioral approach) appears to improve NME. Participants were more satisfied with intervention including neck-specific exercises than with the prescription of general exercise., (Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.)

African Americans with hypertension are at high risk for adverse outcomes from cardiovascular and renal disease. Patients with stage 3 or greater chronic kidney disease have a high prevalence of left ventricular (LV) hypertrophy and diastolic dysfunction. Our goal was to study prospectively the relationships of LV mass and diastolic function with subsequent cardiovascular and renal outcomes in the African American Study of Kidney Disease and Hypertension cohort study. Of 691 patients enrolled in the cohort, 578 had interpretable echocardiograms and complete relevant clinical data. Exposures were LV hypertrophy and diastolic parameters. Outcomes were cardiovascular events requiring hospitalization or causing death; a renal composite outcome of doubling of serum creatinine or end-stage renal disease (censoring death); and heart failure. We found strong independent relationships between LV hypertrophy and subsequent cardiovascular (hazard ratio, 1.16; 95% confidence interval, 1.05-1.27) events, but not renal outcomes. After adjustment for LV mass and clinical variables, lower systolic tissue Doppler velocities and diastolic parameters reflecting a less compliant LV (shorter deceleration time and abnormal E/A ratio) were significantly (P<0.05) associated with future heart failure events. This is the first study to show a strong relationship among LV hypertrophy, diastolic parameters, and adverse cardiac outcomes in African Americans with hypertension and chronic kidney disease. These echocardiographic risk factors may help identify high-risk patients with chronic kidney disease for aggressive therapeutic intervention.

Although electrocardiographic criteria for diagnosing left ventricular hypertrophy have a low sensitivity in the general population, their test characteristics have not been evaluated in the high-prevalence group of American Americans with chronic kidney disease. The purpose of the current study was to evaluate these test characteristics among African Americans (n = 645) with hypertensive kidney disease as part of the African-American Study of Kidney Disease and Hypertension cohort. Electrocardiograms were read by 2 cardiologists at an independent core laboratory using the 2 Sokolow-Lyon criteria and the Cornell criteria. Left ventricular hypertrophy on echocardiography was defined as left ventricular mass index greater than 49.2 and greater than 46.7 g/m(2.7) in men and women, respectively. Sixty-nine percent of the population had left ventricular hypertrophy on echo, whereas 34% had left ventricular hypertrophy by any of the electrocardiographic criteria. Sensitivity by individual electrocardiographic criteria was 16.5% by Sokolow-Lyon-1, 19.3% by Sokolow-Lyon-2, and 24.7% by Cornell criteria, with specificity ranging from 89% to 92%. When using any of the 3 criteria, sensitivity increased to 40.4% with a decrease in specificity to 78.0%. Consistent with findings in a general population, left ventricular hypertrophy by electrocardiography had low sensitivity and high specificity in this cohort of African Americans with hypertensive kidney disease., (Copyright © 2012. Published by Elsevier Inc.)

Troponin levels have been correlated with adverse outcomes in multiple disease processes, including congestive heart failure, acute coronary syndromes, sepsis, and, in a few small series, infective endocarditis. We hypothesized that a novel measurement of troponin using a highly sensitive assay would correlate with adverse outcomes when prospectively studied in patients with infective endocarditis. At a single center in the International Collaboration on Endocarditis, 42 patients met the inclusion criteria and underwent testing for cardiac troponin T (cTnT) using both a standard and a highly sensitive precommercial assay. The cTnT levels were associated with the prespecified primary composite outcome of death, central nervous system event, and cardiac abscess. Secondary outcomes included the individual components of the composite outcome and the need for cardiac surgery. A receiver operating characteristic curve was derived and used to identify the optimal cutpoint for cTnT using the highly sensitive assay. cTnT was detectable with the highly sensitive assay in 39 (93%) of 42 patients with infective endocarditis and with the standard assay in 25 (56%) of 42 (p <0.05). Of the 42 patients, 15 experienced the composite outcome, 4 died, 9 had a central nervous system event, and 5 had a cardiac abscess. With the hs-cTnT assay, the median cTnT was greater in the patients who experienced the primary outcome (0.12 vs 0.02 ng/ml, p <0.05). According to the receiver operating characteristic curve analysis (area under the curve of 0.74), cTnT levels of ≥0.08 ng/ml produced optimal specificity (78%) for the primary outcome. The patients with a cTnT level of ≥0.08 ng/ml were more likely to experience the primary outcome (odds ratio 7.0, 95% confidence interval 1.7 to 28.6, p <0.01) and a central nervous system event (odds ratio 9.3, 95% confidence interval 1.3 to 24.1, p = 0.02). In conclusion, cTnT is detectable in 93% of patients with infective endocarditis using a novel highly sensitive assay, with higher levels correlating with poor clinical outcomes., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Elevated B-type natriuretic peptide (BNP) is a marker of poor outcomes in heart failure, acute coronary syndromes, and sepsis. Elevated cardiac troponin I (cTnI) is associated with adverse outcomes in infective endocarditis. It was hypothesized that elevated BNP would be associated with increased rates of morbidity and mortality in patients with infective endocarditis, particularly when combined with elevated cTnI. Consecutively enrolled patients in the International Collaboration on Endocarditis Prospective Cohort Study (ICE-PCS) were evaluated at a single center. The association between elevated BNP and a composite outcome of death, intracardiac abscess, and central nervous system event and the individual components of the composite was determined. Similar analyses were performed in patients who had BNP and cTnI measured. Of 103 patients, 45 had BNP measured for clinical indications. The median BNP level was higher in patients with the composite outcome (1,498 vs 433 pg/ml, p = 0.03) and in those who died (2,150 vs 628 pg/ml, p = 0.04). Elevated BNP was significantly associated with the composite outcome (p <0.01) and intracardiac abscess (p = 0.02). Patients with elevation of BNP and cTnI had a significantly higher probability of the composite outcome (69%) than patients with either BNP or cTnI elevated (29%) or neither BNP nor troponin elevated (0%) (p for trend <0.01). In conclusion, these data demonstrate a significant association between elevated BNP alone and in combination with cTnI for serious outcomes in infective endocarditis and warrant prospective evaluation., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Aims: This article reviews practical issues that healthcare providers need to consider when implementing therapy with the once-daily glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide., Key Points: Liraglutide is administered once daily by subcutaneous injection, independent of meals and at any time of day. To improve gastro-intestinal tolerability, the starting dose is 0.6 mg liraglutide daily. After at least 1 week, the dose should be increased to 1.2 mg. Some patients may benefit from an additional increment to the maximum recommended daily dose of 1.8 mg. Daily blood glucose monitoring is not required, although may be necessary if liraglutide is used with a sulphonylurea (SU). Treatment is contraindicated in patients with known hypersensitivity to liraglutide or an excipient. Liraglutide slows gastric emptying, but does not interact with acetaminophen, oral contraceptives, atorvastatin, griseofulvin, lisinopril or digoxin in a way that necessitates dose adjustments of these agents. The efficacy and safety of liraglutide are not influenced by differences in gender, age or ethnicity and race. Overall, liraglutide is generally well tolerated. Patients can experience gastrointestinal side effects, such as nausea, which diminish over time. As liraglutide increases insulin production in a glucose-dependent manner, the incidence of hypoglycaemia largely depends on the hypoglycaemic risk profile of the selected oral antidiabetic with which it is used. The use of an SU may increase the risk of hypoglycaemia; this risk can be lowered by reducing the SU dose., Conclusions: Liraglutide is a once-daily treatment option that can be used in adults with type 2 diabetes regardless of gender, age (although therapeutic experience in patients over 75 years of age is limited) and ethnicity or race.

T2DM is a multifaceted disease that requires careful selection of treatment, which must be frequently modified over the continuum of care to attain successful long-term management. A checklist of factors to be considered can be helpful in individualizing treatment for optimal effectiveness based on each patient's needs, concerns, and capabilities.

Objective: To review insulin detemir for clinical use to better manage patients with type 1 and type 2 diabetes., Methods: A MEDLINE search, in English, from June 30, 2006 to December 1, 2008, using the terms "insulin analogs," "insulin detemir" and "long-acting insulin analog.", Results: Insulin detemir improves glycemic control, based on HbA(1C) reduction and fasting glucose levels, without increasing the risk of hypoglycemia and weight gain. Insulin detemir has lower glycemic variability, with less intra-subject variability in blood glucose levels in patients with type 1 and type 2 diabetes, without increasing the risk of hypoglycemia. When added to oral anti-diabetes agents (OADs) in type 2 diabetes, insulin detemir demonstrates superiority to other basal insulin options., Conclusion: Insulin detemir appears to provide better glycemic control with a lower risk of hypoglycemia and less weight gain in the treatment of patients with type 1 and type 2 diabetes.

Elevated troponin is increasingly recognized as a marker of cardiac injury and poor outcomes in diverse disease states. It was hypothesized that patients with infective endocarditis (IE) and elevated cardiac troponin would have more extensive IE and worse clinical outcomes. Patients were enrolled as part of the International Collaboration on Endocarditis (ICE) prospective cohort study; analysis of these patients was done retrospectively. Data from 83 consecutively enrolled patients from a single center were evaluated. Cardiac troponin I (cTnI) was drawn for clinical indications and before any cardiac surgery in 51 of the 83 patients. Outcomes evaluated were hospital mortality, annular or myocardial abscess on the basis of echocardiography or surgery, and central nervous system events. Of 51 patients with cTnI drawn, 33 (65%) had elevated cTnI > or =0.1 mg/dl. There were no differences in age, gender, prosthetic valve IE, Staphylococcus aureus IE, or history of coronary artery disease, congestive heart failure, or diabetes mellitus between patients with and without cTnI elevations. Patients with elevated cTnI were less likely to have isolated right-sided IE and more likely to have left ventricular systolic dysfunction or renal dysfunction (p <0.05 for each). In conclusion, elevated cTnI was associated with the composite of death, abscess, and central nervous system events (p <0.001).

African Americans with hypertensive renal disease represent a high-risk population for cardiovascular events. Although left ventricular hypertrophy is a strong predictor of adverse cardiac outcome, the prevalence and associated factors of left ventricular hypertrophy in this patient population are not well described. The African American Study of Kidney Disease Cohort Study is a prospective, observational study that is an extension of the African American Study of Kidney Disease randomized clinical trial that was conducted from 1994 to 2001 in African Americans with hypertension and mild-to-moderate renal dysfunction. Echocardiograms and 24-hour ambulatory blood pressure monitoring were performed at the baseline visit of the cohort. Of 691 patients enrolled in the cohort study, 599 patients had interpretable baseline echocardiograms and ambulatory blood pressure data. Left ventricular hypertrophy was defined using a cut point for left ventricular mass index >49.2 g/m(2.7) in men and >46.7 m/m(2.7) in women. The majority of patients had left ventricular hypertrophy (66.7% of men and 73.9% of women). In a multiple regression analysis, higher average day and nighttime systolic blood pressure, younger age, and lower predicted glomerular filtration rate were associated with left ventricular hypertrophy, but albuminuria was not. These data demonstrate a striking prevalence of left ventricular hypertrophy in the African American Study of Kidney Disease Cohort and identify potential targets for prevention and therapeutic intervention in this high-risk patient population.

Background: Embolic events to the central nervous system are a major cause of morbidity and mortality in patients with infective endocarditis (IE). The appropriate role of valvular surgery in reducing such embolic events is unclear. The purpose of this study was to determine the relationship between the initiation of antimicrobial therapy and the temporal incidence of stroke in patients with IE and to determine if this time course differs from that shown for embolic events in previous studies., Methods: Prospective incidence cohort study involving 61 tertiary referral centers in 28 countries. Case report forms were analyzed from 1437 consecutive patients with left-sided endocarditis admitted directly to participating centers., Results: The crude incidence of stroke in patients receiving appropriate antimicrobial therapy was 4.82/1000 patient days in the first week of therapy and fell to 1.71/1000 patient days in the second week. This rate continued to decline with further therapy. Stroke rates fell similarly regardless of the valve or organism involved. After 1 week of antimicrobial therapy, only 3.1% of the cohort experienced a stroke., Conclusions: The risk of stroke in IE falls dramatically after the initiation of effective antimicrobial therapy. The falling risk of stroke in patients with IE as a whole precludes stroke prevention as the sole indication for valvular surgery after 1 week of therapy.

Objective: To review intermediate- and long-acting insulins with specific emphasis on the newer insulin analogs., Methods: A MEDLINE search, in English, was conducted with a cut-off of June 30, 2006, using the terms 'NPH insulin', 'insulin analogs', 'insulin glargine', 'insulin detemir' and 'long-acting insulins'. All clinical trials from within the search period were included., Results: The insulin analogs, insulin glargine and insulin detemir, were introduced in an attempt to improve glycemic control among patients with diabetes, without increasing the risk of hypoglycemia. This review indicates that both insulin analogs demonstrate better glycemic control than NPH insulin, based on measurements of HbA1c, fasting glucose and intra-subject variability in blood glucose. This was accomplished with similar or reduced risk of hypoglycemia. Also, insulin detemir appears to be associated with less body weight increase than NPH insulin or insulin glargine., Conclusion: The newer long-acting insulin analogs, insulin detemir and glargine, appear to provide better glycemic control than NPH insulin without increasing the risk of hypoglycemia.

Background: Inflammation has been linked with atherosclerotic disease development and instability. Contributors to systemic inflammation, such as subclinical infection, may trigger acute coronary syndromes (ACSs)., Methods: Using a case-control study design, we evaluated the prevalence of urinary tract infection (UTI) among 100 consecutive ACS patients, compared with a contemporary control group undergoing elective coronary artery bypass graft (CABG) surgery. Cases were excluded if ACS was not confirmed by chart review or if a urinalysis was not obtained

Objective: Compare the efficacy, safety, and patient satisfaction of continuous subcutaneous insulin infusion (CSII) therapy with multiple daily injection (MDI) therapy for patients with type 2 diabetes., Research Design and Methods: A total of 132 CSII-naive type 2 diabetic patients were randomly assigned (1:1) to CSII (using insulin aspart) or MDI therapy (bolus insulin aspart and basal NPH insulin) in a multicenter, open-label, randomized, parallel-group, 24-week study. Efficacy was assessed with HbA(1c) and eight-point blood glucose (BG) profiles. Treatment satisfaction was determined with a self-administered questionnaire. Safety assessments included adverse events, hypoglycemic episodes, laboratory values, and physical examination findings., Results: HbA(1c) values decreased similarly for both groups from baseline (8.2 +/- 1.37% for CSII, 8.0 +/- 1.08% for MDI) to end of study (7.6 +/- 1.22% for CSII, 7.5 +/- 1.22% for MDI). The CSII group showed a trend toward lower eight-point BG values at most time points (only significant 90 min after breakfast; 167 +/- 48 vs. 192 +/- 65 mg/dl for CSII and MDI, respectively; P = 0.019). A total of 93% of CSII-treated subjects preferred the pump to their previous injectable insulin regimen for reasons of convenience, flexibility, ease of use, and overall preference. Safety assessments were comparable for both treatment groups., Conclusions: Insulin aspart in CSII therapy provided efficacy and safety comparable to MDI therapy for type 2 diabetes. Patients with type 2 diabetes can be trained as outpatients to use CSII and prefer CSII to injections, indicating that pump therapy should be considered when initiating intensive insulin therapy for type 2 diabetes.

Cardiac imaging, specifically echocardiography, has greatly enhanced the ability of clinicians to effectively diagnose and manage IE. Echocardiograms should generally be obtained in all patients suspected of having IE, both to establish the diagnosis and to identify complicated cardiac involvement that may warrant surgical intervention. Transesophageal imaging is more sensitive and specific than the transthoracic approach and currently represents the optimal approach to echocardiographic imaging. Manifestations of endocardial involvement include vegetations, abscesses, aneurysms, fistulae, leaflet perforations, and valvular dehiscence. The roles of other imaging modalities including CT, MRI, and nuclear imaging have yet to be fully established.

Atrial Myxomas are benign primary tumors of the heart, arising mainly from the left atrium. Clinical signs and symptoms produced by atrial myxomas may be non-specific or result in mechanical obstruction of cardiac function, arrhythmias, and embolization. The authors present a case of a 60-year-old woman who developed total left hemiparesis resulting from left atrial myxoma embolization causing complete occlusion of the right middle cerebral artery.

With the ability to structurally characterize cardiac manifestations, echocardiography is used for the diagnosis and management of infective endocarditis. In establishing the diagnosis according to the Duke criteria, the findings of endocardial involvement (vegetation, abscess, prosthetic valve dehiscence) or new valvular regurgitation represent "major" diagnostic criteria. As echocardiography cannot reliably differentiate noninfective from infective lesions, however, proper diagnosis lies in correlating echocardiography with clinical findings. The more invasive transesophageal approach provides substantially greater image resolution; this approach should be considered first in the evaluation of patients with higher prior probabilities of endocarditis and those with potential endocardial complications.

Background: Limited data exist on recent demographic and microbiological changes in infective endocarditis (IE) and the impact of these changes on patient survival., Methods: Data were collected from all patients with definite or possible IE at Duke University Medical Center, Durham, NC, from 1993 to 1999. Logistic regression analysis was used to identify demographic and microbiological changes that occurred in patients with IE over the study period. The impact of these changes on survival was evaluated using Cox proportional hazards modeling., Results: Among the 329 study patients, rates of hemodialysis dependence, immunosuppression, and Staphylococcus aureus infection increased during the study period (P=.04, P=.008, and P<.001, respectively), while rates of infection due to viridans group streptococci decreased (P=.007). Hemodialysis was independently associated with S aureus infection (odds ratio, 3.1; 95% confidence interval, 1.6-5.9). Patients with S aureus IE had a higher 1-year mortality rate (43.9% vs 32.5%; P=.04) that persisted after adjustment for other illness severity characteristics (hazard ratio, 1.5; 95% confidence interval, 1.03-2.3)., Conclusions: The demographic and microbiological characteristics of IE at our institution have changed over the past decade in ways that suggest a link between medical practice and IE characteristics. Staphylococcus aureus has emerged as a dominant cause of IE, and is an independent predictor of mortality. These findings identify clinical settings that may warrant closer surveillance and more aggressive measures in the identification and prevention of endocarditis.

Background: Although cardiac device infections (CDIs) are a devastating complication of permanent pacemakers or implantable cardioverter-defibrillators, the incidence of CDI in patients with bacteremia is not well defined. The objective of this study was to determine the incidence of CDI among patients with permanent pacemakers or implantable cardioverter-defibrillators who develop Staphylococcus aureus bacteremia (SAB)., Methods and Results: A cohort of all adult patients with SAB and permanent pacemakers or implantable cardioverter-defibrillators over a 6-year period was evaluated prospectively. The overall incidence of confirmed CDI was 15 of 33 (45.4%). Confirmed CDI occurred in 9 of the 12 patients (75%) with early SAB (<1 year after device placement). Fifteen of 21 patients (71.5%) with late SAB (>/=1 year after device placement) had either confirmed (6 of 21, 28.5%) or possible (9 of 21, 43%) CDI. In 60% of the patients (9 of 15) with confirmed CDI, no local signs or symptoms suggesting generator pocket infection were noted., Conclusions: The incidence of CDI among patients with SAB and cardiac devices is high. Neither physical examination nor echocardiography can exclude the possibility of CDI. In patients with early SAB, the device is usually involved, and approximately 40% of these patients have obvious clinical signs of cardiac device involvement. Conversely, in patients with late SAB, the cardiac device is rarely the initial source of bacteremia, and there is a paucity of local signs of device involvement. The cardiac device is involved, however, in >/=28% of these patients.

Background: Previous studies have generated inconsistent results when attempting to define predictors of stroke and death in patients with endocarditis. We sought to examine the relationship between vegetation 2-dimensional size and stroke in those with infective endocarditis (IE) and to identify differences between aortic valve (AV) and mitral valve (MV) IE with regard to clinical characteristics, echocardiographic findings, stroke, and death., Methods: We used the Duke Endocarditis Database to examine 145 episodes of definite IE involving the AV, n = 62, or MV, n = 83. A logistic regression model was developed to analyze important variables in predicting stroke, and a Cox proportional hazards model was used in predicting mortality., Results: The mitral valve was infected in 57% of the cases. Vegetations were more commonly detected in patients with MV IE (92.8% vs 66.1%, P =.001) and these MV vegetations were significantly larger (P <.05). Thirty-four of 145 episodes (23.4%) were complicated by stroke. MV IE was associated with a greater stroke rate, 32.5% versus 11.3% (P =.003). Strokes tended to occur early in the course of illness, particularly in MV IE. In the multivariable model, the independent predictors of stroke were MV IE (P =.04) and vegetation length (P =.03). Independent predictors of 1-year mortality were age (P =.02) and vegetation area (P =.048)., Conclusion: Stroke is more common in patients with MV IE. Vegetation 2-dimensional size and characteristics are important predictors of stroke and mortality. These findings may lead to predictive models that allow physicians to identify high-risk patients who need aggressive treatment strategies to prevent long-term morbidity and mortality.

Platelet microbicidal proteins (PMPs) are small antimicrobial peptides secreted by mammalian platelets. In vitro resistance of Staphylococcus aureus strains to PMPs correlates with more extensive disease in experimental infective endocarditis (IE). To determine whether this same relationship exists in human S. aureus IE, we evaluated the in vitro PMP susceptibility phenotype of isolates from 58 prospectively-identified patients with definite S. aureus IE. On multivariate analyses, patients with S. aureus IE complicating an infected intravascular device were significantly more likely to have IE caused by a PMP-resistant strain (P=.0193). No correlations were detected between in vitro PMP resistance among S. aureus strains and the severity of human IE. This work supports the concept that in vitro PMP resistance in clinical S. aureus strains is associated with important clinical characteristics of S. aureus endovascular infections in vivo.

We present a novel technique employing biplane cineangiography with simultaneous left coronary and pulmonary angiography to define the anomalous course of the left main coronary artery when it originates from the right sinus of Valsalva. These biplane cinearterlograms clearly define the relationship of the left main coronary artery to the great vessels, allowing confident delineation of the interarterial variant from the other, benign variants. We illustrate the advantages of this technique with two cases in which the course of the anomalous left main coronary artery was incorrectly diagnosed using standard coronary arteriography and magnetic resonance imaging.

A significant problem in the design and construction of an artificial neural network for function approximation is limiting the magnitude and the variance of errors when the network is used in the field. Network errors can occur when the training data does not faithfully represent the required function due to noise or low sampling rates, when the network's flexibility does not match the variability of the data, or when the input data to the resultant network is noisy. This paper reports on several experiments whose purpose was to rank the relative significance of these error sources and thereby find neural network design principles for limiting the magnitude and variance of network errors.

Thirty-nine children from three to 16 years of age were included in this study. Nineteen were diabetics, seven were "suspected" diabetics (with evidence of glucose intolerance but without repeated fasting hyperglycemia), and 13 were controls. Mean glucose disappearance rates (K) during intravenous glucose tolerance tests (IVGTTs) were 2.19 for the controls, 1.23 for the suspected diabetics, and 0.70 for 14 diabetics tested; the differences were statistically significant. Diabetics had the smallest and suspected diabetics the greatest plasma insulin responses during IVGTTs. Fasting plasma growth hormone (GH) varied widely. GH generally decreased or remained unchanged during IVGTTs, but two diabetics exhibited slight increases and two sustpected diabetics pronounced increases. Basement-membrane thickness (BMT) was examined in 42 quadriceps femoris needle biopsies. Average BMT (ABMT) and minimum BMT (MBMT) correlated well (r = 0.91). BMT did not correlate well with age or, in the diabetics, with duration of clinical disease. Diabetics had the greatest and controls the least mean ABMT and MBMT, but the differences were not statistically significant. High values (those exceeding mean control values by more than two standard deviations) were much more common among the suspected diabetics and the diabetics. One of 13 controls, three of six suspected diabetics, and six of 19 diabetics had high ABMT values; two suspected diabetics and five diabetics had high MBMT values. Correlations between BMT and K were negative for the most part, but correlation coefficients were small. Serial studies in four of the children suggest that BMT and glucose tolerance tend to change in opposite directions.

Parametric studies were done on the propagation characteristics of single-mode fiber using measured refractive-index profile data. Two types of profile were considered--a graded-index core with a depressed cladding (Delta' < 0), and a triangular index core with no depressed cladding. The computations employ accurate material dispersion data for the germania-doped silica core and the fluorine-doped silica cladding. The investigation also includes the use of an alpha-index profile as an idealized profile using the same computational method. We find that there is good agreement with the experiments.

Thickness of skeletal muscle's capillary basement membrane was measured in gastrocnemius and quadriceps femoris muscles of diabetic subjects. At least two different sites of each muscle studied were biopsied. Comparison of these biopsy samples revealed a marked and significant variation in thickness of the capillary basement membrane at different sites within the same muscle. In one subject so studied, this variation was found regardless of the method of fixation or the method of measurement of capillary basement membrane thickness used. Variation was present in diabetics suffering from long-term complications of the disease as well as in diabetics free of such complications. A reevaluation of the biologic significance of basement membrane thickness measurements, as presently applied, is indicated in the light of the variability of base-line values.

Mallory bodies (MBs) were obtained in purified form from human liver obtained at autopsy using a new procedure consisting of sedimentation through a Ficoll viscosity barrier. Preparations from six livers ranged in purity from 95 to 99 per cent. MB preparations were autofluorescent. MBs were strongly agglutinated by Concanavalin A. The presence of carbohydrate was also indicated by the fact that MBs bound fluorescently labeled Concanavalin A; no binding was observed in the presence of appropriate inhibitor monosaccharides. Direct analysis indicated that MBs contained variable amounts of neutral hexose (0.65 to 2.4 mumoles of glucose-equivalents per milligram of protein) but no sialic acid. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that purified MBs contain five major polypeptides possessing apparent molecular weights of 56,000, 48,500 to 45,000 (triplet), and 32,500. Periodic acid-Schiff-positive components were not detected. Scanning electron microscopy of isolated MBs revealed the presence of a rough, fibrous surface, whereas conventional transmission electron microscopy indicated the filamentous nature of MBs.

Based on a set of exact vector form solutions to Maxwell's equations for optical waveguides, we studied the parametric effects on propagation characteristics of the HE(11) mode, varying the lightguide parameters (lambda,Delta,a,alpha). In this work a three-term Sellmeier equation was employed to describe accurately the material dispersion of a single-mode fiber doped with GeO(2). The calculated results are compared with the measured values and found to be in good agreement.

Blizzard, John L. (University of Houston, Houston, Texas) and G. E. Peterson. Selective inhibition of proline-induced pigmentation in washed cells of Serratia marcescens. J. Bacteriol. 85:1136-1140. 1963.-Streptomycin, chloramphenicol, and tetracyclines inhibited the synthesis of prodigiosin by Serratia marcescens strain D1. This occurred at concentrations of the antibiotic too low to inhibit the growth of the organism in either agar media or broth cultures. Nonpigmented cells were produced in broth by either adding streptomycin or incubating at 37 C. After being washed and resuspended in aqueous saline containing either casein hydrolysate, l-proline, or a glycine-succinate mixture and incubated at 27 C for 24 hr, these cells formed pigment. The appearance of pigment was preceded by a lag period of 10 hr. Prodigiosin production by these washed suspensions of cells was completely inhibited by either streptomycin or glucose, or by incubation at 37 C instead of 27 C. Even though pigmentation by washed-cell suspensions was induced by proline, the utilization of proline was not affected by streptomycin or glucose, or by incubation at 37 C. To block pigmentation completely, streptomycin had to be added to proline-supplemented cells before they were 10 hr old. Addition of the antibiotic after the end of the induction period caused either partial or no inhibition of pigment production. Streptomycin caused an increase in the endogenous respiration of S. marcescens but failed to affect the constitutive enzymes that oxidize glucose. The possible relationships of these phenomena are discussed. Weil (1952) reported that low concentrations of chloramphenicol and certain tetracyclines inhibit the synthesis of prodigiosin while permitting growth by Serratia marcescens. He noted the potential value to "mode-of-action" studies of an organism having certain functions selectively inhibited by antibiotics. We confirmed Weil's (1952) observations and found that streptomycin at low concentration would also inhibit the synthesis of prodigiosin without impeding growth. Further studies of the selective inhibition of prodigiosin synthesis by streptomycin were performed using nonproliferating suspensions of washed cells (Gott and Williams, 1961). Either a glycine-succinate mixture or l-proline could cause nonproliferating cells to form pigment. A period of induction preceded the formation of pigment. Either streptomycin or glucose, or an incubation temperature of 37 C, inhibited the proline-induced pigmentation by washed cells. Further investigations provided insights to these findings.