Breast vibro-acoustography: initial experience in benign lesions

Background

Functional magnetic resonance imaging (fMRI) analysis is commonly done with cross-correlation analysis (CCA) and the General Linear Model (GLM). Both CCA and GLM techniques, however, typically perform calculations on a per-voxel basis and do not consider relationships neighboring voxels may have. Clustered voxel analyses have then been developed to improve fMRI signal detections by taking advantages of relationships of neighboring voxels. Mean-shift clustering (MSC) is another technique which takes into account properties of neighboring voxels and can be considered for enhancing fMRI activation detection.

Methods

This study examines the adoption of MSC to fMRI analysis. MSC was applied to a Statistical Parameter Image generated with the CCA technique on both simulated and real fMRI data. The MSC technique was then compared with CCA and CCA plus cluster analysis. A range of kernel sizes were used to examine how the technique behaves.

Results

Receiver Operating Characteristic curves shows an improvement over CCA and Cluster analysis. False positive rates are lower with the proposed technique. MSC allows the use of a low intensity threshold and also does not require the use of a cluster size threshold, which improves detection of weak activations and highly focused activations.

Conclusion

The proposed technique shows improved activation detection for both simulated and real Blood Oxygen Level Dependent fMRI data. More detailed studies are required to further develop the proposed technique.     

Eating attitudes and behaviors in adolescent women: Discrimination of normals,dieters, and suspected bulimics using the eating attitudes test and eating disorder inventory

The prevalence of eating disorders has increased in teenage and young adult women. Since early treatment of eating disorders is thought to lead to improved outcomes, the development of an effective self-report screening device for eating disorders in adolescents could help reduce morbidity from these illnesses. In order to examine the feasibility of developing such an instrument, eating attitudes and behaviors were studied in a sample of 72 female adolescents, using the Eating Attitudes Test (EAT), the Eating Disorder Inventory (EDI), and blinded structured clinical interviews focused on eating disorders. Scores on the EAT and EDI were similar to scores of older normal female comparison groups in other studies. Based upon interview information, 54 subjects were classified as normal, 9 as dieters, 8 as suspected bulimics, and 1 as bulimic. Subjects, on average, accurately reported their actual weight and height. The results of the interviews indicated that 25% of the 72 subjects were currently dieting, 60% regularly skipped meals, 35% said they were overweight or very overweight, 22% were binge eaters, 8% vomited after eating, and 4% used drugs to lose weight. Linear discriminant analysis was used to compare the results of the questionnaires with that of the interviews in order to identify a composite set of questionnaire items to be used as a screening device for individuals with clinical eating disorders and for those at high risk of developing such disorders. A preliminary equation was obtained that correctly classified 86% of subjects into categories of normal, dieter, or suspected bulimic that were determined from the interviews. These preliminary data suggest that adolescents' scores on the EAT and the EDI are similar to young adult women's scores, and also that further refinement of a discriminant equation might lead to the development of an effective screening device for eating disorders in adolescents.     

Metabolic and target organ outcomes after total pancreatectomy: Mayo Clinic experience and meta‐analysis of the literature

Introduction Total pancreatectomy (TP) has been associated with substantial metabolic abnormalities and poor glycaemic control limiting its use. Because data reported to date are limited, we evaluated outcomes related to the diabetes mellitus obligated by TP. Methods A case series study of all patients who underwent TP from 01/01/1985 to 12/31/2006 at Mayo Clinic was conducted. TP cases were summarized according to perioperative procedures, mortality and morbidity after TP. To complement this retrospective examination, a survey was developed to measure DM treatment modality, target organ failure and complications in patients alive in 2007. We performed a meta‐analysis to compare our results with similar previous studies and provide overall estimates of outcomes. Results A total of 141 cases were studied (97 malignant diseases, 44 benign diseases). The median survival was much less for malignant pathology (2·2 vs 8·7 years, Log rank P = 0·0009). In 2007, there were 59 patients that were presumed alive and 47 (80%) responded to the survey. Mean HbA1c at last follow‐up was 7·5% with 89% of respondents on a complex insulin programme (mean daily insulin requirement 35 ± 13 units). Episodic hypoglycaemia was experienced by 37 (79%); 15 (41%) experienced severe hypoglycaemia. In contrast, diabetic ketoacidosis developed in only 2 (4%). Target organ complications and chronic diarrhoea developed in 13 patients (28%) each. Conclusion The primary factor determining survival after TP is the aetiology necessitating TP, i.e. pancreatic malignancy. Most respondents used complex insulin programmes, but hypoglycaemia continues to be a problem.     

Predictors of early recovery from major depression among persons admitted to community-based clinics: an observational study

BACKGROUND: Twenty years have elapsed since the National Institute of Mental Health Collaborative Depression Study reported on the early course and treatment of major depression within the mental health sector. Using similar methods, an observational study was conducted to assess relationships between initial depression severity, personality dysfunction and other baseline characteristics, subsequent treatment, and 3-month outcomes among persons admitted to public and voluntary sector outpatient clinics, including 1 academic program. METHODS: A 2-stage sampling technique was used to recruit subjects (N = 165) diagnosed by the Structured Clinical Interview for DSM-IV, Patient Version, as having a major depression episode. Sociodemographic and clinical characteristics were assessed at admission. Data on treatment and outcome were obtained at 3 months using structured instruments from the Longitudinal Interview Follow-up Evaluation. Logistic regression was used to assess hypothesized predictors of early recovery. Analyses were carried out in the total sample and after dichotomizing subjects by baseline depression severity. RESULTS: Fifty (30.3%) of the 165 subjects met recovery criteria. Less than half of the subjects (45%) met criteria for adequate pharmacotherapy. Less severe depression, having received adequate antidepressant treatment, female sex, and being married independently predicted early recovery. In the more depressed subgroup, early recovery was associated with female sex. Among less severely depressed subjects, high personality dysfunction scores and being married were significant predictors. CONCLUSIONS: Initial depression severity and receiving adequate pharmacotherapy predict early recovery in individuals with major depression seeking outpatient treatment. A minority of persons receive intensive antidepressant treatment. Less severe personality dysfunction and being married predicts early recovery among persons with less severe depression.     

Health service use among persons with comorbid bipolar and substance use disorders

OBJECTIVE: This study tested the hypothesis that patients with comorbid bipolar and substance use disorders use health services to a greater extent than patients with either bipolar or substance use disorder alone. METHODS: A retrospective chart review was conducted among patients who used health services at the Ralph H. Johnson Department of Veterans Affairs medical center in Charleston, South Carolina, and had bipolar disorder alone, substance use disorder alone, and comorbid bipolar and substance use disorders. Patients with a psychiatric admission between 1999 and 2003 were included in the study. Information was collected on the use of health services one year before and including the index admission. RESULTS: The records of 106 eligible patients were examined for this study: 18 had bipolar disorder alone, 39 had substance use disorder alone, and 49 had both bipolar and substance use disorders. Compared with the other two groups, the group with comorbid bipolar and substance use disorders was significantly more likely to be suicidal. Compared with the group with bipolar disorder alone, the group with comorbid disorders had significantly fewer outpatient psychiatric visits and tended to have shorter psychiatric hospitalizations. Among patients with an alcohol use disorder, those who also had bipolar disorder were significantly less likely than those with an alcohol use disorder alone to have had an alcohol-related seizure. Patients with comorbid bipolar and substance use disorders were significantly less likely than those with substance use disorder alone to be referred for intensive substance abuse treatment, even though both groups were equally likely to enter and complete treatment when they were referred. CONCLUSIONS: Despite significant functional impairment among patients with comorbid bipolar and substance use disorders, they had significantly fewer psychiatric outpatient visits than those with bipolar disorder alone and were referred for intensive substance abuse treatment significantly less often than those with substance use disorder alone.     

Application of stochastic processes to participant recruitment in clinical trials

The allocation of sufficient time for participant recruitment is one of the fundamental aspects in planning a clinical trial. This paper illustrates how a Poisson process can be used to determine an optimal period of time for participant recruitment by simulating Poisson arrival into a clinical trial. The simulation study provides the means to generate of an empirical probability density function for the recruitment time based on time-dependent changes in the accrual rate. From this empirical distribution, a clinical trial recruitment period can be planned to provide a high level of confidence (e.g., 90% probability) of enrolling the sample size within the planned amount of time given the simulation assumptions.     

The anthrax protective antigen (PA63) bound conformation of a peptide inhibitor of the binding of lethal factor to PA63: as determined by trNOESY NMR and molecular modeling

Anthrax protective antigen (PA) is one of the three proteins produced by the gram positive bacteria Bacillus anthracis collectively known as the "anthrax toxin" (Ascenzi, P.; Visca, P.; Ippolito, G.; Spallarossa, A.; Bolognesi, M.; et al. Anthrax toxin: a tripartite lethal combination. FEBS Lett. 2002, 531, 384-388). The role played by PA in anthrax intoxication is to transport the two enzymes lethal factor (LF) and edema factor (EF) into the cell. Collier and co-workers (Mourez, M.; Kane, R. S.; Mogridge, J.; Metallo, S.; Deschatelets, P.; et al. Designing a polyvalent inhibitor of anthrax toxin. Nat. Biotechnol. 2001, 958). reported the isolation of two peptides via phage display that bind to the PA63 heptamer and inhibit its interaction with LF and EF, and thereby prevent the transport of LF and EF into the cell. One of these peptides, His-Thr-Ser-Thr-Try-Trp-Trp-Leu-Asp-Gly-Ala-Pro (P1), was selected for structural investigation on the basis of its ability to prevent the binding of LF to the PA63 heptamer bundle. Two-dimensional trNOESY experiments coupled with NOE restrained simulated annealing calculations were used to determine the PA63-bound conformation of P1. On binding to PA63, P1 adopts a helical conformation involving residues 3-9 while the C- and N-terminal residues exhibit dynamic fraying.     

Central venous catheter occlusion: a prospective, controlled trial examining the impact of a positive-pressure valve device

BACKGROUND: Central venous catheter (CVC) occlusion occurs frequently in children. This problem is often associated with disruption of intravascular therapy and monitoring. Multiple factors may predispose to catheter occlusion, but reflux of blood into the catheter lumen is a common factor. We hypothesized that use of a positive pressure valve device would reduce the incidence of catheter occlusion. METHODS: In phase I of this sequential study design, newly placed CVCs were capped with a standard device. In Phase II, CVCs were capped with a positive-pressure valve device. Data collected included patient demographics, type of catheter, infusate, catheter duration, and complications. Partial and complete catheter occlusions were delineated. A user satisfaction survey was conducted. RESULTS: There were 153 children (mean age 48.0 +/- 7.7 months) with 312 CVC lumens enrolled in the study. Mean catheter duration was 9.4 +/- 0.9 days. There were fewer complete occlusions in CVCs capped with the positive pressure valve device than with the standard device [6/161 (3.7%) vs 18/151 (11.9%) occlusions, respectively; p = .012)]. There were no significant differences in partial occlusions, phlebitis, or catheter-related bloodstream infection between the 2 groups. CONCLUSIONS: CVCs with a positive-pressure valve cap device have a lower incidence of complete catheter occlusion than those with a standard cap device.     

Continuous subcutaneous insulin infusion and multiple daily injection therapy are equally effective in type 2 diabetes: a randomized,parallel-group, 24-week study

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.