An international survey of imaging practices in radiotherapy.

Improvements in delivery of radiation dose to target tissues in radiotherapy have increased the need for better image quality and led to a higher frequency of imaging patients. Imaging for treatment planning extends to function and motion assessment and devices are incorporated into medical linear accelerators (linacs) so that regions of tissue can be imaged at time of treatment delivery to ensure dose distributions are delivered as accurately as possible. A survey of imaging in 97 radiotherapy centres in nine countries on six continents has been undertaken with an on-line questionnaire administered through the International Commission on Radiological Protection mentorship programme to provide a snapshot of imaging practices. Responses show that all centres use CT for planning treatments and many utilise additional information from magnetic resonance imaging and positron emission tomography scans. Most centres have kV cone beam CT attached to at least some linacs and use this for the majority of treatment fractions. The imaging options available declined with the human development index (HDI) of the country, and the frequency of imaging during treatment depended more on country than treatment site with countries having lower HDIs imaging less frequently. The country with the lowest HDI had few kV imaging facilities and relied on MV planar imaging intermittently during treatment. Imaging protocols supplied by vendors are used in most centres and under half adapt exposure conditions to individual patients. Recording of patient doses, a knowledge of which is important in optimisation of imaging protocols, was limited primarily to European countries.

Failed preoperative vacuum bell therapy does not affect outcomes following minimally invasive repair of pectus excavatum.

PURPOSE: It is unknown if failed preoperative vacuum bell (VB) treatment in patients undergoing minimally invasive repair of pectus excavatum (MIRPE), delays repair and/or affects postoperative outcomes. METHODS: A retrospective data analysis including all consecutive patients treated at one single institution undergoing MIRPE was performed between 2000 and 2016. Patients were stratified into preoperative VB therapy versus no previous VB therapy. RESULTS: In total, 127 patients were included. Twenty-seven (21.3%) patients had preoperative VB treatment for 17 months (median, IQR 8-34). All 27 patients stopped VB treatment due to the lack of treatment effect. Eight (47.1%) of 17 assessed VB patients showed signs of skin irritation or hematoma. VB treatment had no effect on length of hospital stay (p = 0.385), postoperative complications (p = 1.0), bar dislocations (p = 1.0), and duration of bar treatment (p = 0.174). Time spent in intensive care unit was shorter in patients with VB therapy (p = 0.007). Long-term perception of treatment including rating of primary operation (p = 0.113), pain during primary operation (p = 0.838), own perspective of look of chest (p = 0.545), satisfaction with the procedure (p = 0.409), and intention of doing surgery again (p = 1.0) were not different between groups. CONCLUSIONS: Failed preoperative VB therapy had no or minimal effect on short-term outcomes and long-term perceptions following MIRPE.

Intestinal IMINO transporter SIT1 is not expressed in human newborns.

The expression of amino acid transporters in small intestine epithelia of human newborns has not been studied yet. It is further not known whether the maturation of imino acid (proline) transport is delayed as in the kidney proximal tubule. The possibility to obtain small intestinal tissue from patients undergoing surgery for jejunal or ileal atresia during their first days after birth was used to address these questions. As control, adult terminal ileum tissue was sampled during routine endoscopies. Gene expression of luminal imino and amino acid transporter SIT1 (SLC6A20) was approximately threefold lower in newborns versus adults. mRNA levels of all other luminal and basolateral amino acid transporters and accessory proteins tested were similar in newborn mucosa compared with adults. At the protein level, the major luminal neutral amino acid transporter B0AT1 (SLC6A19) and its accessory protein angiotensin-converting enzyme 2 were shown by immunofluorescence to be expressed similarly in newborns and in adults. SIT1 protein was not detectable in the small intestine of human newborns, in contrast to adults. The morphology of newborn intestinal mucosa proximal and distal to the obstruction was generally normal, but a decreased proliferation rate was visualized distally of the atresia by lower levels of the mitosis marker Ki-67. The mRNA level of the 13 tested amino acid transporters and accessory proteins was nonetheless similar, suggesting that the intestinal obstruction and interruption of amniotic fluid passage through the small intestinal lumen did not affect amino acid transporter expression. NEW & NOTEWORTHY System IMINO transporter SIT1 is not expressed in the small intestine of human newborns. This new finding resembles the situation in the proximal kidney tubule leading to iminoglycinuria. Lack of amniotic fluid passage in small intestinal atresia does not affect amino acid transporter expression distal to intestinal occlusion.

[How does vaping products work]. / Comment fonctionnent les produits du vapotage.

To maximize the chances of replacing smoking with vaping, it is necessary to know the different types of existing devices, their characteristics and their most important settings as well as their influence on sensations. To support a user it is also important to understand the nature of the inhaled and exhaled vapor, as well as the possible mistakes that can lead to a less enjoyable experience. Highlighting e-liquids formulations and emissions can help understanding how a minimum of 95 % risk reduction compared to tobacco smoking is achieved and the influence of compounds on the user's experience. At last, a proper care, especially to refill the device and to change the resistance is the key to an effective use over time.

[Ertapenem administered intravenously or subcutaneously for urinary tract infections caused by ESBL producing enterobacteriacea]. / Ertapénem intraveineux ou sous-cutané pour le traitement des infections urinaires à entérobactérie sécrétrice de BLSE.

INTRODUCTION: Ertapenem could be used to treat urinary tract infections (UTI) caused by ESBL producing enterobacteriacae (ESBL-E) and administered subcutaneously. METHOD: The authors made a retrospective study on adult patients treated with ertapenem administered intravenously or subcutaneously for UTI caused by ESBL-E, between May 2009 and August 2011 at the Chambery hospital, France. RESULTS: Twenty-five patients were treated (13 cases of prostatitis, ten of pyelonephritis, two of cystitis) mostly caused by Escherichia coli (24 cases). Subcutaneous injections were administered to 20 patients and 23 were treated through outpatient parenteral antibiotic therapy (OPAT). All patients were cured at the end of the ertapenem therapy. Urine samples collected during treatment for 12 patients were sterile. Three months after the end of the treatment, five patients had relapsed, and six had developed a UTI caused by another bacteria. CONCLUSION: Ertapenem administered intravenously or subcutaneously could be an effective treatment for UTI caused by ESBL-E, especially using OPAT.

SU-E-T-446: Effect of Dose Calculation Grid Size Variability on the Specification of Spinal Cord Dose Tolerance for Spinal Stereotactic Body Radiation Therapy.

PURPOSE: To investigate the effect of the dose grid resolution variability on the spinal cord dose for spinal SBRT treatments. METHOD: 10 CyberKnife plans were selected for the proximity of the PTV to the spinal cord. All dose distributions were calculated with Monte Carlo using high spatial resolution and minimal relative uncertainty. The plans were renormalized to a 16 Gy prescription dose and to ensure a target coverage > 95% in order to compare the calculated dose distributions. Each dose matrix was resampled 12 times, covering a grid resolution range of 0.95 mm to 13.52 mm. The spinal cord DVHs were generated for each resampled dose grid. The variations of the maximum point dose (DmaxCord) and dose-coverage to partial volumes (D[V]) up to 5 cc were investigated against the grid resolution. RESULTS: The mean variation of DmaxCord with grid resolution is characterized by an inverse power law, with a sharp initial decrease leading to potentially large underestimates of DmaxCord (24%, 40% and 55% at resolutions of 2 mm, 4 mm and 8 mm). The variability of mean D[V] values decreases from smaller to larger grid resolutions, however large disparities are observed between patient plans. We introduced the variability threshold volume (Vth) as a constraint to express the dose coverage independently from the grid resolution. For resolutions up to 8 mm, the mean Vth value is (0.96±0.10) cc with a corresponding dose coverage of (26± 12) % relative to the initial DmaxCord value. CONCLUSIONS: Dose distributions calculated with grid resolutions larger than 2 mm could Result in significant underestimates of DmaxCord. Furthermore, the sensitivity of the dose coverage to grid resolution variability is patient dependent. Consequently, a specified cord dose tolerance should be quoted at a particular grid resolution uniformly adopted between institutions; 2 mm or less is an appropriate value.

Lifetime measurement of the 2(1)+ state in 20C.

Establishing how and when large N/Z values require modified or new theoretical tools is a major quest in nuclear physics. Here we report the first measurement of the lifetime of the 2(1)+ state in the near-dripline nucleus 20C. The deduced value of τ(2(1)+)=9.8±2.8(stat)(-1.1)(+0.5)(syst) ps gives a reduced transition probability of B(E2; 2(1)+→0(g.s.)+)=7.5(-1.7)(+3.0)(stat)(-0.4)(+1.0)(syst) e2 fm4 in good agreement with a shell model calculation using isospin-dependent effective charges.

Nuclear structure relevant to neutrinoless double beta decay: 76Ge and 76Se.

The possibility of observing neutrinoless double beta decay offers the opportunity of determining the effective neutrino mass if the nuclear matrix element were known. Theoretical calculations are uncertain, and measurements of the occupations of valence orbits by nucleons active in the decay can be important. The occupation of valence neutron orbits in the ground states of 76Ge (a candidate for such decay) and 76Se (the daughter nucleus) were determined by precisely measuring cross sections for both neutron-adding and removing transfer reactions. Our results indicate that the Fermi surface is much more diffuse than in theoretical calculations. We find that the populations of at least three orbits change significantly between these two ground states while in the calculations, the changes are confined primarily to one orbit.

Lifetime measurement of the first excited 2+ state in 16C.

The lifetime of the 2_+(1) state in 16C has been measured with the recoil distance method using the 9Be(9Be,2p) fusion-evaporation reaction at a beam energy of 40 MeV. The mean lifetime was measured to be 11.7(20) ps corresponding to a B(E2;2_+(1)-->0+) value of 4.15(73)e_2 fm_4 [1.73(30) W.u.], consistent with other even-even closed shell nuclei. Our result does not support an interpretation for "decoupled" valence neutrons.

From chiral vibration to static chirality in (135)Nd.

Electromagnetic transition probabilities have been measured for the intraband and interband transitions in the two sequences in the nucleus (135)Nd that were previously identified as a composite chiral pair of rotational bands. The chiral character of the bands is affirmed and it is shown that their behavior is associated with a transition from a vibrational into a static chiral regime.

Single-neutron states in (101)Sn.

The first data on the relative single-particle energies outside the doubly magic (100)Sn nucleus were obtained. A prompt 171.7(6) keV gamma-ray transition was correlated with protons emitted following the beta decay of (101)Sn and is interpreted as the transition between the single-neutron g(7/2) and d(5/2) orbitals in (101)Sn. This observation provides a stringent test of current nuclear structure models. The measured nug(7/2)-nud(5/2) energy splitting is compared with values calculated using mean-field nuclear potentials and is used to calculate low-energy excited states in light Sn isotopes in the framework of the shell model. The correlation technique used in this work offers possibilities for future, more extensive spectroscopy near (100)Sn.

Molecular analysis of relapse vs re-infection in HIV-positive patients suffering from recurrent Clostridium difficile associated diarrhoea.

Recurrence is a major complication of Clostridium difficile associated diarrhoea, especially in human immunodeficiency virus (HIV) positive patients, and it is important to distinguish between relapse and re-infection in recurrent episodes. The aim of our study was to analyse C. difficile isolates obtained from HIV-positive patients with recurrent diarrhoea in order to distinguish between relapse and re-infection. This analysis was based on the study of DNA similarities among isolates obtained from different episodes within each patient. Relapses occurred in 64% of patients, 32% suffered re-infections and a combination of relapse plus re-infection was seen in 4%. DNA typing methods can be useful tools to characterize recurrent episodes of C. difficile associated disease.

Rapid detection of toxigenic Clostridium difficile from stool samples by a nested PCR of toxin B gene.

Toxigenic Clostridium difficile is the aetiologic agent of most cases of antibiotic-associated diarrhoea and pseudomembranous colitis. The present standard method for C. difficile diagnosis is a cytotoxicity assay, performed on human fibroblast cultures. It is time consuming and requires special facilities. A nested-PCR assay detecting toxin B gene within a few hours was designed. One hundred and two stool samples were collected during four months. All samples were processed for toxin B-PCR, cultured for C. difficile and tested for cytotoxicity. This approach achieved 99% concordance with the cytotoxic assay. The sensitivity and specificity for the new PCR assay were 96.3% and 100% respectively. The procedure described is easy to perform, does not require special equipment and has produced excellent results. It deserves serious consideration for routine clinical microbiology laboratory use.

Improving clinical outcome in bacteremia.

Bacteremia is associated with significant morbidity and mortality. There is wide variation in morbidity and mortality rates according to organism and predisposing conditions. Additionally, prompt administration of appropriate antimicrobial agents is associated with a decrease in mortality. Unfortunately, many bacteremic patients receive inappropriate or no antibiotics. Infectious disease consultation can decrease the number of patients receiving inappropriate initial therapy. 'Quality standard for the treatment of bacteremia' (Gross et al., 1994, Infection Control and Hospital Epidemiology 15, 189-192) is a consensus paper; its purpose is to 'improve the treatment of hospitalized patients with documented bacteremia by ensuring that they receive an antibiotic appropriate in light of the blood-culture susceptibility of the pathogen isolated.' A programme to assess the treatment of bacteremia can improve the quality of care with a modest commitment of additional resources. Many of the activities could be performed by a pharmacist, infection control practitioner, or pathologist. However, physician-to-physician communications are most likely to be successful. This programme should be considered a component of a hospital's quality-improvement programme; either the hospital quality assurance or infection control committee could be responsible for the programme. We encourage adoption of the standard, and recommend prospective monitoring to include the choice of empiric antimicrobial agents.

Implementation of consensus guidelines for the follow-up of positive blood cultures.

OBJECTIVE: Assess the effect and use of resources associated with implementation of a program for the systematic follow-up of positive blood cultures. DESIGN: Prospective epidemiologic study. SETTING: Tertiary-care military medical center. INTERVENTION: All positive blood cultures (BC) were reported via E-mail to an infectious disease specialist as soon as growth was noted. This individual reviewed all Gram stains, clinical data, and antibiotic information on these patients. RESULTS: From June 26, 1994, through January 25, 1995, there were 3,121 BCs drawn, of which 199 (6.4%) were positive from 145 episodes. Sixty-three episodes involved probable contaminants, and 82 episodes were considered true bacteremias. Six patients with true bacteremia died, two were transferred, and three were discharged within 24 hours of drawing the positive BC. Of the remaining 71 true bacteremias, 9 patients were on inadequate empiric therapy, as judged by the final organism susceptibilities. Changes in empiric therapy were recommended for five of the nine episodes and were implemented by the primary physicians in each case. Each of the changes resulted in improved coverage (as judged by the final identification and susceptibilities). CONCLUSIONS: This program has improved the quality of care at Keesler Medical Center at the cost of one additional hour of consultant time per week.

Cyclosporine administration decreases liver vitamin A stores in normal and vitamin A-deficient rats.

Thirty-four Wistar rats were fed a marginal or normal vitamin A diet and received daily for 14 days an intragastric intubation of oil supplemented with 0, 20, or 60 mg X kg-1 of cyclosporine A. The hepatic content and concentration of vitamin A were significantly decreased by cyclosporine treatment, whereas no modification occurred in kidney or serum vitamin A levels. No induction of hepatic cytochrome P-450 was observed in treated animals. These results suggest that cyclosporine interferes with vitamin A stores; thus, vitamin A supplementation may be useful in patients receiving cyclosporine therapy. Drug-metabolizing enzymes, which are cytochrome P-450 dependent, did not seem to be involved in the hepatic vitamin A decrease observed.