Redistribution of joint moments is associated with changed plantar pressure in diabetic polyneuropathy

Background  

Patients with diabetic polyneuropathy (DPN) are often confronted with ulceration of foot soles. Increased plantar pressure under the forefoot has been identified as a major risk factor for ulceration. This study sets out to test the hypothesis that changes in gait characteristics induced by DPN related muscle weakness are the origin of the elevated plantar pressures.     

Noise-Induced Variability of Immuno-PET with Zirconium-89-Labeled Antibodies: an Analysis Based on Count-Reduced Clinical Images

Purpose

Positron emission tomography (PET) with Zirconium-89 (Zr-89)-labeled antibodies can be used for in vivo quantification of antibody uptake. Knowledge about measurement variability is required to ensure correct interpretation. However, no clinical studies have been reported on measurement variability of Zr-89 immuno-PET. As variability due to low signal-to-noise is part of the total measurement variability, the aim of this study was to assess noise-induced variability of Zr-89 -immuno-PET using count-reduced clinical images.

Procedures

Data were acquired from three previously reported clinical studies with [⁸⁹Zr]antiCD20 (74 MBq, n?=?7), [⁸⁹Zr]antiEGFR (37 MBq, n?=?7), and [⁸⁹Zr]antiCD44 (37 MBq, n?=?13), with imaging obtained 1 to 6 days post injection (D0–D6). Volumes of interest (VOIs) were manually delineated for liver, spleen, kidney, lung, brain, and tumor. For blood pool and bone marrow, fixed-size VOIs were used. Original PET list mode data were split and reconstructed, resulting in two count-reduced images at 50 % of the original injected dose (e.g., 37 MBq_74inj).Repeatability coefficients (RC) were obtained from Bland-Altman analysis on standardized uptake values (SUV) derived from VOIs applied to these images.

Results

The RC for the combined manually delineated organs for [⁸⁹Zr] antiCD20 (37 MBq_74inj) increased from D0 to D6 and was less than 6 % at all time points. Blood pool and bone marrow had higher RC, up to 43 % for 37 MBq_74inj at D6. For tumor, the RC was up to 42 % for [⁸⁹Zr]antiCD20 (37 MBq_74inj). For [⁸⁹Zr]antiCD20, (18 MBq_74inj), [⁸⁹Zr]antiEGFR (18 MBq_37inj), and [⁸⁹Zr]antiCD44 (18 MBq_37inj), measurement variability was independent of the investigated antibody.

Conclusions

Based on this study, noise-induced variability results in a RC for Zr-89-immuno-PET (37 MBq) around 6 % for manually delineated organs combined, increasing up to 43 % at D6 for blood pool and bone marrow, assuming similar biodistribution of antibodies. The signal-to-noise ratio leads to tumor RC up to 42 %.

     

Median frequency--a new parameter for predicting defibrillation success rate

STUDY HYPOTHESIS: Current American Heart Association guidelines recommend immediate defibrillation of ventricular fibrillation. When this is unsuccessful, there are no guidelines to help determine the optimum time at which to defibrillate after the administration of an alpha-adrenergic agonist. Previous studies have shown that the median frequency of the ventricular fibrillation ECG signal correlates with myocardial perfusion during CPR. We hypothesized that median frequency could predict the success of defibrillation and thus accurately determine the most appropriate time at which to defibrillate during ventricular fibrillation. STUDY POPULATION: Twenty-two mixed-breed swine weighing more than 15 kg were studied. METHODS: Ventricular fibrillation was induced electrically, and the ventricular fibrillation ECG signal was analyzed using fast Fourier analysis. After ten minutes of ventricular fibrillation, mechanical CPR was begun. After three minutes of CPR, the animals received one of three alpha-adrenergic agonists and CPR was continued. Defibrillation was attempted three and one-half minutes after drug administration. The average median frequency 20 seconds before defibrillation was calculated. Sensitivity and specificity of median frequency with respect to defibrillation success were determined. RESULTS: A median frequency of 9.14 Hz had a sensitivity of 100% and a specificity of 92.31% in predicting the results of defibrillation in this model. CONCLUSION: The median frequency may serve as a valuable parameter to guide defibrillation therapy during ventricular fibrillation.     

Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome

Alterations in intestinal microbiota are associated with obesity and insulin resistance. We studied the effects of infusing intestinal microbiota from lean donors to male recipients with metabolic syndrome on the recipients' microbiota composition and glucose metabolism. Subjects were assigned randomly to groups that were given small intestinal infusions of allogenic or autologous microbiota. Six weeks after infusion of microbiota from lean donors, insulin sensitivity of recipients increased (median rate of glucose disappearance changed from 26.2 to 45.3 μmol/kg/min; P < .05) along with levels of butyrate-producing intestinal microbiota. Intestinal microbiota might be developed as therapeutic agents to increase insulin sensitivity in humans; www.trialregister.nl; registered at the Dutch Trial Register (NTR1776).     

Selection of probiotic bacteria for prevention of allergic diseases: immunomodulation of neonatal dendritic cells

Modification of intestinal microbiota early in life by administration of probiotic bacteria may be a potential approach to prevent allergic disease. To select probiotic bacteria for in vivo purposes, we investigated the capacity of probiotic bacteria to interact with neonatal dendritic cells (DC) and studied the ensuing T cell polarizing effect. Immature DC were generated from cord blood-derived monocytes and maturation was induced by maturation factors (MF), lipopolysaccharide (LPS) plus MF and Bifidobacterium bifidum, B. infantis, Lactobacillus salivarius, Lactococcus lactis alone or combined with MF. After 12 days of co-culture with DC and Staphylococcus aureus enterotoxin B (SEB) as antigenic stimulus, cytokine production by autologous T cells was determined by intracellular cytokine staining. Additionally, cells were stimulated with CD3 and CD28 monoclonal antibodies and cytokines were measured in supernatants by multiplex assay. The probiotic strains induced partial maturation of DC. Full maturation of DC was induced for all strains tested when MF was added. The percentage of interleukin (IL)-4 producing T cells was lower in T cell cultures stimulated with B. bifidum matured DC compared to MF and LPS matured DC, which coincided with a higher percentage of interferon (IFN)-gamma-producing T cells. Furthermore, T cells stimulated by B. bifidum matured DC produced significantly more IL-10 compared to MF matured DC. Selected species of the Bifidobacterium genus prime in vitro cultured neonatal DC to polarize T cell responses and may therefore be candidates to use in primary prevention of allergic diseases.