Agreement and reproducibility of gray‐scale intravascular ultrasound and optical coherence tomography for the analysis of the bioresorbable vascular scaffold

Objective : To report the agreement between gray‐scale intravascular ultrasound (GS‐IVUS) and optical coherence tomography (OCT) in assessing the bioresorbable vascular scaffolds (BVS) structures and their respective reproducibility. Background : BVS are composed of an erodible polymer. Ultrasound and light signals backscattered from polymeric material differs from metallic stents using GS‐IVUS and OCT. Methods : Forty‐five patients included in the ABSORB trial were treated with a 3.0 × 18 mm BVS and imaged with GS‐IVUS 20 MHz and OCT post‐implantation. Qualitative (ISA, side‐branch struts, protrusion, and dissections) and quantitative (number of struts, lumen, and scaffold area) measurements were assessed by two investigators. The agreement and the inter‐ and intraobserver reproducibility were investigated using the kappa (κ) and the interclass correlation coefficient (ICC). Results : GS‐IVUS and OCT agreement was predominantly poor at a lesion, frame, and strut level analysis (κ and ICC <0.4) for qualitative measurements. GS‐IVUS demonstrated a reduced ability to detect cross‐sections with ISA (4.5% vs. 20.6%), side‐branch (SB) struts (6.3% vs. 7.8%), protrusions (3.2% vs. 9.6%), and dissections (0.2% vs. 9.0%) compared with OCT. GS‐IVUS reproducibility was poor–moderate (κ and ICC <0.6) except for ISA and SB‐struts (κ and ICC between 0.2 and 0.75). OCT showed an excellent reproducibility (κ and ICC > 0.75) except for the assessment of tissue protrusion (κ and ICC between 0.47 and 0.94). GS‐IVUS reproducibility was poor–moderate (ICC ≤ 0.5) in assessing the number of struts but excellent with OCT (ICC > 0.85). The reproducibility to assess lumen and scaffold areas was excellent using both techniques (ICC > 0.85). Conclusions : GS‐IVUS has a poor capacity to detect qualitative findings post‐BVS implantation and its reproducibility is low compared with OCT. The use of GS‐IVUS should be limited when assessing lumen and scaffold areas. © 2011 Wiley Periodicals, Inc.     

Evaluation of Hemodynamic Changes Using Different Intra-Abdominal Pressures for Laparoscopic Cholecystectomy

Biliary diseases known since ages constitute major portion of digestive tract disorders world over. Among these cholelithiasis being the fore runner causing general ill health, thereby requiring surgical intervention for total cure. The study was undertaken in an attempt to compare the hemodynamic changes in patient undergoing laparoscopic cholecystectomy using different intra-abdominal pressures created due to carbon dioxide insufflation. The patients were randomly allocated to one of the three groups in which different levels of intra-abdominal pressures (8–10 mmHg,11–13 mmHg and 14 mmHg and above) were maintained. The base line parameters monitored were heart rate, non invasive blood pressur(systolic and mean)and end tidal carbon dioxide. All the parameters were monitored at various intervals i.e. Immediately during insufflation, 5 min, 10 min, 20 min, 30 min after CO2 insufflation and after every 10 min if surgery exceeds 30 min, at exsufflation,10 min after CO2 exsufflation. Patients were ventilated with Pedius Drager Ventilator keeping tidal volume 8–10 ml/kg and respiratory rate 12–14 breaths/min. During surgery patients were placed in reverse Trendlenburg position (head up) at 15 °. The results obtained were evaluated statistically and analyzed. Baseline characteristics were found to be comparable. Hemodynamic variables were reported as mean and standard deviation. Statistical significance among groups was evaluated using Analysis of Variance and unpaired student t test (two tailed). Inter-group comparisons were made using Bonferroni test. A p-value of <0.05 was considered as statistically significant. In all the three groups the mean heart rate (baseline 84.08 ± 12.50, 87.96 ± 15.73 and 86.92 ± 17.00 respectively) increased during CO2 insufflation and the rise in heart rate continued till exsufflation after which it decreased and at 10 min after exsufflation the heart rates were comparable with the baseline. The inter-group comparison of mean heart rate between I & III was statistically significant at 10, 20, 30 min after CO2 insufflation which continued at exsufflation and 10 min after CO2 exsufflation [p < 0.05]. The inter-group comparison between I & III showed statistically significant difference in systolic blood pressure at 10, 20, 30 min after CO2 insufflation, at exsufflation and 10 min after exsufflation [p = 0.0001] and mean arterial pressure at 5, 10, 20, 30 min after CO2 insufflation, at exsufflation and 10 min after exsufflation [p = 0.0001]. Comparison between Group I and Group III & between Group II and Group III showed highly significant statistical difference in EtCO2 immediately after insufflation and the same trend was seen till the completion of surgery and even 10 min after exsufflation [p = 0.001]. The conclusion drawn from the study was that laparoscopic cholecystectomy induces significant hemodynamic changes intraoperatively, the majority of pathophysiological changes are related to cardiovascular system and are caused by CO2 insufflation .A high intra-abdominal pressure due to CO2 insufflation is associated with more fluctuations in hemodynamic parameters and increased peritoneal absorption of CO2 as compared to low intraabdominal pressure so low pressure pneumoperitoneum is feasible for laparoscopic cholecystectomy and minimizes the adverse hemodynamic effects of CO2 insufflation.

Electronic supplementary material

The online version of this article (doi:10.1007/s12262-012-0484-x) contains supplementary material, which is available to authorized users.     

Biomarkers of β-Cell Stress and Death in Type 1 Diabetes

The hallmark of type 1 diabetes (T1D) is a decline in functional β-cell mass arising as a result of autoimmunity. Immunomodulatory interventions at disease onset have resulted in partial stabilization of β-cell function, but full recovery of insulin secretion has remained elusive. Revised efforts have focused on disease prevention through interventions administered at earlier disease stages. To support this paradigm, there is a parallel effort ongoing to identify circulating biomarkers that have the potential to identify stress and death of the islet β-cells. Whereas no definitive biomarker(s) have been fully validated, several approaches hold promise that T1D can be reliably identified in the pre-symptomatic phase, such that either β-cell preservation or immunomodulatory agents might be employed in at-risk populations. This review summarizes the most promising protein- and nucleic acid-based biomarkers discovered to date and reviews the context in which they have been studied.     

Management of humeral fracture nonunion in severe osteoporosis by a combination of locking plating and intramedullary fibular grafting

Nonunion of the humerus in a severely osteoporotic bone is a likely event especially if the fracture is transverse. The management of such a combination is a challenge. Most of the conventional fixation methods are unlikely to succeed as the bone failure precedes implant failure in osteoporosis. The challenge is further compounded in severe osteoporosis when the cortical thickness is affected more severely. We used a combination of an intramedullary fibula with a locking plate in 5 cases. The results show that it may be a good combination in such situations as the bone strength is augmented and the plate pullout is less likely.     

Carnosic acid ameliorates depressive‐like symptoms along with the modulation of FGF9 in the hippocampus of middle carotid artery occlusion‐induced Sprague Dawley rats

The increased survival rate of stroke patients has led to the higher incidences of post‐stroke depression. Carnosic acid has the ability to cross blood brain barrier with good neuro‐modulatory actions. Recently, inclined level of fibroblast growth factor 9 (FGF9) in the postmortem brain of the depressed patients was noted. Therefore, in the present study, the effect of carnosic acid on post‐stroke depression‐like behavior, and the expression of FGF9 were evaluated. After 3 weeks of middle carotid artery occlusion in Sprague Dawley rats, carnosic acid (20 and 40 mg/kg) was administered for 2 weeks. Sucrose preference test, forced swimming test, and open field test were performed and hippocampi were analyzed for FGF9 and FGFR‐3. In comparison to post‐stroke depressed rats, carnosic acid increased the sucrose preference, and reduced the immobility time of the rats by ~2×. The speed and distance‐covered were also increased. At 40 mg/kg, FGF9 was reduced by ~3× while FGFR‐3/Actin was increased by ~1.5×. Altogether results suggest anti‐depressant‐like activity of carnosic acid in post‐stroke depressed rats with decreased expression of hippocampal FGF9.     

Re-visiting pH-adjusted potassium to avoid hypokalemic crisis during management of diabetic ketoacidosis: A conceptual framework

Background and aimsDiabetic ketoacidosis (DKA) treatment guidelines recommend to initiate potassium-replacement when serum potassium (S_K) drops within normal range, and to withhold insulin if S_K is below normal. Despite strict recommendations, hypokalemia is frequently observed in DKA.MethodsScientific literature was thoroughly searched to find 1) DKA treatment guidelines, 2) studies reporting hypokalemia in DKA, 3) and literature elaborating mechanisms involved in hypokalemia.ResultsAcidosis affects S_K and its regulators including insulin, catecholamines and aldosterone. Current conceptual framework is an argument to gauge the degree of hypokalemia before it strikes DKA patients utilizing S_K level after adjusting it with pH. Suggested approach will reduce hypokalemia risk and its associated complications. The nomogram calculates pH-adjusted potassium and expected potassium loss. It also ranks hypokalemia associated risk, and proposes the potassium-replacement rate over given time period. The differences between current DKA treatment guidelines and proposed strategy are also discussed. Moreover, reasons and risk of hyperkalemia due to early initiation of potassium replacement and remedial actions are debated.ConclusionIn light of proposed strategy, utilizing the nomogram ensures reduced incidence of hypokalemia in DKA resulting in improved clinical and patient outcomes. Pharmacoeconomic benefits can also be expected when avoiding hypokalemia ensures early discharge.     

Improvement of DC Breakdown Strength of the Epoxy/POSS Nanocomposite by Tailoring Interfacial Electron Trap Characteristics

To date, breakdown voltage is an underlying risk to the epoxy-based electrical high voltage (HV) equipment. To improve the breakdown strength of epoxy resin and to explore the formation of charge traps, in this study, two types of polyhedral oligomeric silsesquioxane (POSS) fillers are doped into epoxy resin. The breakdown voltage test is performed to investigate the breakdown strength of neat epoxy and epoxy/POSS composites. Electron traps that play an important role in breakdown strength are characterized by thermally stimulated depolarized current (TSDC) measurement. A quantum chemical calculation tool identifies the source of traps. It is found that adding octa-glycidyl POSS (OG-POSS) to epoxy enhances the breakdown strength than that of neat epoxy and epoxycyclohexyl POSS (ECH-POSS) incorporated epoxy. Moreover, side groups of OG-POSS possess higher electron affinity (E_A) and large electronegativity that introduces deep-level traps into epoxy resin and restrain the electron transport. In this work, the origin of traps has been investigated by the simulation method. It is revealed that the functional properties of POSS side group can tailor an extensive network of deep traps in the interfacial region with epoxy and enhance the breakdown strength of the epoxy/POSS nanocomposite.     

Appendiceal endosalpingiosis: clinical presentation and imaging appearance of a rare condition of the appendix

Abdominal Radiology - Endosalpingiosis rarely affects the appendix but can be mistaken for acute appendicitis or appendiceal tumors. The medical literature regarding appendiceal endosalpingiosis is...     

Determination of anti-cyclic citrullinated peptide antibodies in the sera of patients with juvenile idiopathic arthritis

OBJECTIVE: Anti-cyclic citrullinated peptide (anti-CCP) antibodies have been found in sera of 76% of patients with rheumatoid arthritis (RA), mainly in rheumatoid factor (RF) positive patients, with a specificity of 96%. We evaluated the presence of anti-CCP antibodies in patients with juvenile idiopathic arthritis (JIA) and assessed the possibility of synthetic citrullinated peptides as antigenic determinants in JIA. METHODS: The presence of anti-CCP antibodies was determined using 3 synthetic citrullinated peptide variants and 2 commercial kits (Inova Diagnostics and Axis-Shield Diagnostics) optimized for detecting JIA-specific antibodies in serum by an ELISA based assay. We evaluated 66 patients with JIA (16 RF positive polyarthritis, 18 RF negative polyarthritis, 19 oligoarthritis, and 13 systemic arthritis). We also tested 9 adult RA patients, 34 patients with systemic lupus erythematosus (SLE), and 25 healthy persons as controls. RESULTS: Significant concentrations of anti-CCP antibodies were detected in the majority of RF positive JIA patients with polyarthritis. Using the 2 synthetic linear peptides, 12/16 (75%) were positive; 9/12 (75%) were positive with the Inova kit and 9/10 (90%) were positive with the Axis-Shield kit. However, utilizing the synthetic linear peptides, significant concentrations of anti-CCP antibodies were detected in 51/66 (77%) JIA patients, including 15/18 (83%) RF negative polyarthritis, 16/19 (84%) oligoarthritis, and 8/13 (62%) systemic arthritis patients. No healthy control showed elevated antibody levels. In contrast, 4/9 (44%) patients with adult RA and 2/6 (33%) with SLE had elevated anti-CCP levels. The synthetic cyclic variant cfc-1-cyc yielded significant anti-CCP levels for 13/14 (93%) patients with RF negative polyarthritis, 6/10 (60%) with oligoarthritis, and 3/7 (43%) with systemic arthritis, and 8/9 (88%) RF positive patients. No healthy control had increased anti-CCP levels. However, 4/9 (44%) adult RA and 9/34 (26%) SLE patients were found to have elevated anti-CCP levels. Using the Inova and Axis-Shield kits, much smaller percentages were found in the RF negative patients, with only 4/16 (25%) in the oligoarthritis and RF negative polyarthritis patients with the Inova kits and 0/25 (0%) by the Axis-Shield kits. The Inova kit revealed elevated anti-CCP antibodies in 5/9 (56%) adult RA patients and in 8/34 (24%) SLE patients. No healthy control had elevated anti-CCP antibodies. However, the Axis-Shield kits did not detect anti-CCP antibodies in adult RA (0/9) or SLE (0/34) patients. Moreover, 0/25 (0%) healthy individuals exhibited anti-CCP levels. The presence of anti-CCP antibodies correlated more frequently with the presence of RF. CONCLUSION: This study confirms the presence of anti-CCP antibodies in patients with JIA, especially those with RF positive polyarthritis, by all ELISA based methods. Use of synthetic peptides also revealed anti-CCP antibodies in a percentage of RF negative patients with polyarthritis, oligoarthritis, and systemic arthritis; there was a loss in specificity, but an increase in sensitivity. These results suggest that antibodies to these antigenic peptides may be markers for JIA, and indicate a possible role of citrulline-containing epitopes in the pathogenesis of JIA.