Citations

Background: Intraoperative C-arm fluoroscopy and low-dose O-arm are both reasonable means to assist in screw placement for idiopathic scoliosis surgery. Both using pediatric low-dose O-arm settings and minimizing the number of radiographs during C-arm fluoroscopy guidance decrease patient radiation exposure and its deleterious biological effect that may be associated with cancer risk. We hypothesized that the radiation dose for C-arm-guided fluoroscopy is no less than low-dose O-arm scanning for placement of pedicle screws. Methods: A multicenter matched-control cohort study of 28 patients in total was conducted. Fourteen patients who underwent O-arm-guided pedicle screw insertion for spinal fusion surgery in 1 institution were matched to another 14 patients who underwent C-arm fluoroscopy guidance in the other institution in terms of the age of surgery, body weight, and number of imaged spine levels. The total effective dose was compared. A low-dose pediatric protocol was used for all O-arm scans with an effective dose of 0.65 mSv per scan. The effective dose of C-arm fluoroscopy was determined using anthropomorphic phantoms that represented the thoracic and lumbar spine in anteroposterior and lateral views, respectively. The clinical outcome and complications of all patients were documented. Results: The mean total effective dose for the O-arm group was approximately 4 times higher than that of the C-arm group (P<0.0001). The effective dose for the C-arm patients had high variability based on fluoroscopy time and did not correlate with the number of imaged spine levels or body weight. The effective dose of 1 low-dose pediatric O-arm scan approximated 85 seconds of the C-arm fluoroscopy time. All patients had satisfactory clinical outcomes without major complications that required returning to the operating room. Conclusions: Radiation exposure required for O-arm scans can be higher than that required for C-arm fluoroscopy, but it depends on fluoroscopy time. Inclusion of more medical centers and surgeons will better account for the variability of C-arm dose due to distinct patient characteristics, surgeon’s preference, and individual institution’s protocol. Level of Evidence: Level III–case-control study.

Background Probe‐based confocal laser endomicroscopy (pCLE) provides microscopic imaging during an endoscopic procedure. Its introduction as a standard modality in gastroenterology has brought significant progress in management strategies, affecting many aspects of clinical care and requiring standardisation of practice and training. Objective This study aimed to provide guidance on the standardisation of its practice and training in Barrett's oesophagus, biliary strictures, colorectal lesions and inflammatory bowel diseases. Methods Initial statements were developed by five group leaders, based on the available clinical evidence. These statements were then voted and edited by the 26 participants, using a modified Delphi approach. After two rounds of votes, statements were validated if the threshold of agreement was higher than 75%. Results Twenty‐six experts participated and, among a total of 77 statements, 61 were adopted (79%) and 16 were rejected (21%). The adoption of each statement was justified by the grade of evidence. Conclusion pCLE should be used to enhance the diagnostic arsenal in the evaluation of these indications, by providing microscopic information which improves the diagnostic performance of the physician. In order actually to implement this technology in the clinical routine, and to ensure good practice, standardised initial and continuing institutional training programmes should be established.

AbstractSarcopenia, or loss of skeletal muscle mass, is associated with increased mortality and morbidity in liver transplant (LT) candidates. Six‐minute walk distance (6MWD) and health‐related quality of life (HRQOL) as assessed by short form 36 scores (SF‐36) also impact clinical outcomes in these patients. This study explored the relationship between the sarcopenia, 6MWD, and HRQOL in LT candidates. Sarcopenia was evaluated based on skeletal muscle mass index (SMI) quantified from abdominal computed tomography. Patients were followed until death, removal from the wait list or the end of the study period. Two hundred and thirteen patients listed for LT were included. The mean SMI, 6MWD and mean gait speed were 54.3 ± 9.7, 370.5 m and 1 m/s, respectively. Sarcopenia was noted in 22.2% of LT candidates. There was no correlation between sarcopenia, 6MWD, and SF‐36 scores. The 6MWD, but not sarcopenia, was an independent predictor of mortality (hazard ratio = 2.1 [0.9–4.7]). In summary, sarcopenia did not emerge as a significant predictor of waitlist mortality and also failed to correlate with either functional capacity or HRQOL in LT candidates. In patients with ESLD awaiting LT, 6MWD appears to be a more useful prognostic indicator than the presence of sarcopenia.

Key Points Zebrafish flt3 plays an important role in the initiation of definitive hematopoietic stem cells. Expression of human FLT3-ITD activates endogenous flt3 signaling and induces myeloid expansion.

Key PointsMGUS patients have significantly increased cortical bone porosity and reduced bone strength relative to matched controls.

Type A insulin resistance, associated with acanthosis nigricans and menstrual irregularity, has been ascribed to a decreased concentration of insulin receptors. We now report four affected females from one family, a mother and three daughters (including identical twins) who appear to have the type A syndrome. Two of the kindred had no apparent ovarian dysfunction, while the other two had hyperprolactinemia without other findings of polycystic ovary disease, suggesting a genetic disease with variable penetrance. All had normal erythrocyte and monocyte insulin binding. Insulin dose-response studies to assess glucose metabolism and insulinsensitivity were performed in the affected twins. The dose response to insulin was shifted to the right with a decrease in maximal response. These results are consistent with a postbinding defect in insulin action in these patients.

Abstract Epimorphin/syntaxin-2 is a membrane-tethered protein localized extracellularly (Epim) and intracellularly (Stx-2). The extracellular form Epim stimulates morphogenic processes in a range of tissues, including in murine mammary glands where its overexpression in luminal epithelial cells is sufficient to drive hyperplasia and neoplasia. We analyzed WAP-Epim transgenic mice to gain insight into how Epim promotes malignancy. Ectopic overexpression of Epim during postnatal mammary gland development led to early side-branching onset, precocious bud formation, and increased proliferation of mammary epithelial cells. Conversely, peptide-based inhibition of Epim function reduced side branching. Because increased side branching and hyperplasia occurs similarly in mice upon overexpression of the progesterone receptor isoform-a (Pgr-a), we investigated whether Epim exhibits these phenotypes through Pgr modulation. Epim overexpression indeed led to a steep upregulation of both total Pgr mRNA and Pgr-a protein levels. Notably, the Pgr antagonist RU486 abrogated Epim-induced ductal side branching, mammary epithelial cell proliferation, and bud formation. Evaluation of Epim signaling in a three-dimensional ex vivo culture system showed that its action was dependent on binding to its extracellular receptor, integrin-αV, and on matrix metalloproteinase 3 activity downstream of Pgr-a. These findings elucidate a hitherto unknown transcriptional regulator of Pgr-a, and shed light on how overexpression of Epim leads to malignancy. Cancer Res; 73(18); 5719–29. ©2013 AACR.