Positive visualization of implanted devices with susceptibility gradient mapping using the original resolution

In magnetic resonance imaging, implantable devices are usually visualized with a negative contrast. Recently, positive contrast techniques have been proposed, such as susceptibility gradient mapping (SGM). However, SGM reduces the spatial resolution making positive visualization of small structures difficult. Here, a development of SGM using the original resolution (SUMO) is presented. For this, a filter is applied in k‐space and the signal amplitude is analyzed in the image domain to determine quantitatively the susceptibility gradient for each pixel. It is shown in simulations and experiments that SUMO results in a better visualization of small structures in comparison to SGM. SUMO is applied to patient datasets for visualization of stent and prostate brachytherapy seeds. In addition, SUMO also provides quantitative information about the number of prostate brachytherapy seeds. The method might be extended to application for visualization of other interventional devices, and, like SGM, it might also be used to visualize magnetically labelled cells. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.     

The value of tumour markers in lung cancer

The pre-treatment serum levels of neuron-specific enolase (NSE), phosphohexose isomerase (PHI) and circulating immune complexes (CC) as tumour markers were compared to measurements of standard haematology and biochemical indices in 73 patients with lung cancer, as an aid to differentiation of tumour type, estimating disease extent, predicting response to therapy and prognosis. Elevated NSE greater than or equal to 12.5 ng ml-1, PHI greater than or equal to 55 mgl-1 levels were observed in 55% of cases for NSE, 90% for PHI and 49% for CC. NSE was significantly elevated in 61% (25/41) of patients with SCLC (P less than 0.005) compared to 41% (13/32) with NSCLC. CC levels were significantly raised in 72% (23/32) of patients with NSCLC (P less than 0.05) compared to 32% with SCLC. The levels of NSE and PHI were not related to tumour stage but CC was significantly raised in limited compared to extensive disease in SCLC (P less than 0.05). Serum albumin was significantly lower in NSCLC compared to SCLC, and median values of alkaline phosphatase, gamma-glutamyltranspeptidase and aminoaspartate transferase were significantly higher in patients with extensive disease. The pre-treatment serum values of NSE, PHI, and CC did not predict the response to therapy or prognosis in the 73 patients with lung cancer. The most important prognostic factor was the number of abnormal routine laboratory parameters (greater than 4) in this group of patients.     

Effect of environmental conditions on the fluoride sensitivity of acid production by S. sanguis NCTC 7865

Growth and environmental conditions affected the fluoride (F) sensitivity of acid production by Streptococcus sanguis NCTC 7865. Cells grown glucose-limited in a chemostat were generally more sensitive than those harvested from cultures in which there was an excess of glucose (amino acid-limited). There was no consistent relationship between the growth rate of cells and their F sensitivity. Slower-growing cells (mean generation time = 14 hr) were more sensitive than those growing quickly when glucose was the limiting nutrient, whereas the faster growing cells from the glucose-excess culture were most susceptible. The pH of the environment markedly affected the F sensitivity of cells: 2 mM F- was sufficient to abolish acid production by cells incubated at pH 5.0, whereas 24 mM F- did not totally inhibit glycolysis at pH 7.0 or 8.0. Regardless of pH and growth conditions, the cationic composition of the environment had the most pronounced effect on acid production and fluoride sensitivity. Cells washed and re-suspended in KCl were more acidogenic and more sensitive to F than the same cells treated with saline. At pH 7.0 and 8.0, saline-washed cells were comparatively unaffected by F, while glycolysis by the same cells at the same pH but washed in KCl could be inhibited by up to 80%. These results suggested that F inhibition could not be explained merely on the basis of HF uptake at low pH values. Since it has been shown previously that the activity of the energized membrane is maintained by K+ and dissipated in the presence of Na+, it was proposed that proton motive force (pmf) might be involved in the uptake of F-.     

Bamboo skewer perforation of the bowel: Computed tomography appearances

A 25-year-old Chinese woman presented with a painful left-lower-quadrant abdominal mass. Computed tomography (CT) demonstrated a dense forked foreign body within an extraluminal mass. A 2.5 cm bamboo skewer surrounded by inflamed omentum was found at laparotomy. Different CT densities of bamboo skewers were obtained when exposed to air, water and 2% Gastrografin in an in vitro experiment. Awareness of the possible variations in appearances of wooden foreign bodies in and around the bowel may aid their CT diagnoses.     

Three-compartment wrist arthrography: use of a low-iodine-concentration contrast agent to decrease study time

To decrease examination time, the authors used a contrast agent with a low iodine concentration for three-compartment (radiocarpal joint, distal radioulnar joint, midcarpal compartment) wrist arthrography. The material was used in 24 patients. Many patients demonstrated dissipation of contrast material in the radiocarpal joint by 30 minutes after injection. By 45 minutes, all patients demonstrated sufficient dissipation to permit the second injection. The technique produces diagnostic images and reduces the time required for the study.     

The contrasting influence of chronic nicotine intake on gastrin and gastric acid secretion

The effects of chronic nicotine treatment on gastric acid secretion stimulated by subcutaneous injection of pentagastrin, as well as on serum gastrin levels and the stomach parietal cell population, were examined. Rats drank a solution of nicotine 25 μg/mL tap water for periods of 10, 30 or 45 days. Pentagastrin increased the gastric secretory volume and acid output in pylorus-ligated control animals that drank tap water. Animals given nicotine in their drinking water for 10, 30 or 45 days showed increased basal gastric secretion and acid output. Pentagastrin produced maximum stimulatory effects at lower dose levels of 50 μg/kg in the 10-day treatment group and 25 μg/kg in the 30- or 45-day treatment groups; however, the maximum responses to pentagastrin in all nicotine-treated batches were comparable to those of their corresponding controls. Serum gastrin levels remained unchanged from the 10th day of nicotine treatment, whereas the levels in the control animals continued to rise with age. Nicotine 25 μg/mL drinking water given for 10, 30 or 45 days caused no significant changes in the parietal cell population, mucosal surface area or mucosal thickness. These findings are consistent with the idea that chronic nicotine administration, for at least 10 days, will lead to increased muscarinic receptor sensitivity; basal acid secretion is consequently elevated, and this in turn may depress gastrin secretion.     

Risky behavior in teens with cystic fibrosis or sickle cell disease: a multicenter study

OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens.     

Factors associated with the duration of breastfeeding amongst women in Perth, Australia

Duration of breastfeeding was studied in 556 women delivering at 2 maternity hospitals in Perth, Australia. At discharge 83.8% of women were breastfeeding their infants, including 6% who were giving complementary feeds. At 3 and 6 months, 61.8% and 49.9%, respectively, were still breastfeeding. In a Cox survival analysis of factors associated with duration of breastfeeding a positive association was found with maternal education, age and intended duration of breastfeeding. Male infants were more likely to be weaned before female infants and women whose partners were unemployed, or did not have a preference for breastfeeding, breastfed for shorter duration. There is still a need for programmes which support and encourage breastfeeding, focusing particularly on younger, less well-educated women who intend to breastfeed for less than the recommended 4-6 months.     

Oral chronic graft‐versus‐host disease: current pathogenesis,therapy, and research

Optimal management of complex autoimmune diseases requires a multidisciplinary medical team including dentists to care for lesions of the oral cavity. In this review, we discuss the presentation, prevalence, diagnosis, and treatment of oral manifestations in chronic graft‐versus‐host disease (cGVHD), which is a major late complication in patients treated by allogeneic hematopoietic stem cell transplantation. We assess current general knowledge of systemic and oral cGVHD and present general treatment recommendations based on literature review and our clinical experience. Additionally, we review areas where the understanding of oral cGVHD could be improved by further research and address tools with which to accomplish the long‐term goal of providing better health and quality of life to patients with cGVHD.     

Increased resistance to plasmic degradation of fibrin with highly crosslinked alpha-polymer chains formed at high factor XIII concentrations

We have previously demonstrated that increasing factor XIII concentrations above that present in plasma (1 U/mL) results in the formation of very high molecular weight alpha fate polyacrylamide and agarose gel electrophoresis (SDS-PAGE). In this report, we have examined the effect of such crosslinking on plasmic susceptibility of fibrin prepared from purified fibrinogen and from plasma in the presence of factor XIII concentrations between 0 and 10 U/mL. The crosslinking achieved with purified fibrinogen at 1 U/mL factor XIII increased resistance to plasmic degradation by 32% as measured in a radiolabeled clot lysis system. However, further increases in plasmic resistance occurred at factor XIII concentrations of 2 and 10 U/mL, the latter decreasing the lysis rate to 45% of that which occurred in the absence of factor XIII. To achieve the same rate of clot lysis with fibrin formed using 10 U/mL rather than 1 U/mL of factor XIII, an increase in plasmin concentration of up to 4.2-fold was required. Similar results were obtained using clots prepared from plasma in the presence of factor XIII concentrations greater than 1 U/mL. Since the alpha 2-plasmin inhibitor content was the same for fibrin at 1 or 10 U/mL factor XIII, the increasing plasmic resistance could not be attributed to increased binding of the inhibitor. We conclude that fibrin prepared in the presence of factor XIII at concentrations exceeding that in plasma shows increased resistance to plasmic degradation, which is likely explained by the formation of very high molecular weight alpha polymer chains.