Quantitation of the reconstruction quality of a four-dimensional computed tomography process for lung cancer patients

We have developed a four-dimensional computed tomography (4D CT) technique for mapping breathing motion in radiotherapy treatment planning. A multislice CT scanner (1.5 mm slices) operated in ciné mode was used to acquire 12 contiguous slices in each couch position for 15 consecutive scans (0.5 s rotation, 0.25 s between scans) while the patient underwent simultaneous quantitative spirometry measurements to provide a sorting metric. The spirometry-sorted scans were used to reconstruct a 4D data set. A critical factor for 4D CT is quantifying the reconstructed data set quality which we measure by correlating the metric used relative to internal-object motion. For this study, the internal air content within the lung was used as a surrogate for internal motion measurements. Thresholding and image morphological operations were applied to delineate the air-containing tissues (lungs, trachea) from each CT slice. The Hounsfield values were converted to the internal air content (V). The relationship between the air content and spirometer-measured tidal volume (v) was found to be quite linear throughout the lungs and was used to estimate the overall accuracy and precision of tidal volume-sorted 4D CT. Inspection of the CT-scan air content as a function of tidal volume showed excellent correlations (typically r>0.99) throughout the lung volume. Because of the discovered linear relationship, the ratio of internal air content to tidal volume was indicative of the fraction of air change in each couch position. Theoretically, due to air density differences within the lung and in room, the sum of these ratios would equal 1.11. For 12 patients, the mean value was 1.08 +/- 0.06, indicating the high quality of spirometry-based image sorting. The residual of a first-order fit between v and V was used to estimate the process precision. For all patients, the precision was better than 8%, with a mean value of 5.1% +/- 1.9%. This quantitative analysis highlights the value of using spirometry as the metric in sorting CT scans. The 4D reconstruction provides the CT data required to measure the three-dimensional trajectory of tumor and lung tissue during free breathing.     

Hematophagous Diptera collected from a horse and paired carbon dioxide-baited suction trap in southern California: relevance to West Nile virus epizootiology

Hematophagous Diptera landing on a horse were removed by vacuum, and their numbers were related to a paired carbon dioxide-baited suction trap at three locations in southern California where West Nile virus activity was high during the preceding year. Insects collected from the horse included mosquitoes (nine species), biting midges (Culicoides sonorensis Wirth & Jones), and black flies (Simulium bivittatum Malloch). Mosquitoes were predominantly collected from the head, crest, withers, neck, chest, and shoulders of the horse, whereas biting midges and black flies were predominantly collected from the ventral midline of the horse. Culex erythrothorax Dyar was by far the most abundant mosquito species collected overall. Frequency of engorgement for mosquitoes captured from the horse ranged by species from zero to 58.3%, with Culex pipiens quinquefasciatus Say having the lowest value (16.7% or one of six mosquitoes) of species that fed on the horse. The number of insects captured at the horse and paired CO2-baited suction trap was not different for Anopheles franciscanus McCracken, Culex tarsalis Coquillett, and S. bivittatum. Cx. p. quinquefasciatus was captured in greater numbers in the CO2-baited suction trap, whereas Anopheles hermsi Barr & Guptavanji, Cx. erythrothorax, Culiseta inornata (Williston), and Culiseta particeps (Adams) were captured in greater numbers from the horse. The horse biting rate was very low for Cx. p. quinquefasciatus, intermediate for Cx. tarsalis, and very high for Cx. erythrothorax. Both Cx. tarsalis and Cx. erythrothorax should be considered likely epizootic vectors of West Nile virus to horses in rural southern California.     

Localization of endogenous galactoside-binding lectin during morphogenesis ofXenopus laevis

Summary A monoclonal antibody has been produced againstXenopus laevis galactoside-binding neural-creststage lectin. This antibody inhibits lectin-mediated hemagglutination. Using this antibody in conjunction with immunohistochemical techniques, lectin deposition has been studied in embryos and tadpoles at different stages of morphogenesis, from initial neural crest migration, up to the formation of a swimming tadpole. Lectin levels change during development in different regions of the embryo and tadpole, decreasing in migratory cells, and increasing in sites where cells become more adhesive to one another. The results suggest that galactoside-binding lectins may be an important class of cellular adhesion molecules during these stages of development.     

Proceed? Mesh for Laparoscopic Ventral Hernia Repair

Background and Objectives:

Laparoscopic technique to repair ventral hernia offers advantages over conventional open surgery such as shorter recovery time, decreased pain, and lower recurrence rates. There are a myriad of meshes available for laparoscopic repair of ventral hernias. This study evaluated the outcomes of laparoscopic repair of ventral hernias with Proceed mesh (Ethicon, Somerville, NJ, USA) in a single academic institution.

Methods:

An institutional review board–approved retrospective review was performed for 100 consecutive patients with ventral hernia who underwent a laparoscopic approach at our institution from August 2006 to February 2009. All patients were operated on by a single surgeon using a standard technique with transabdominal suture fixation and tacks.

Results:

The study included 100 consecutive patients (57 female and 43 male patients). The mean age was 55 years (range, 16–78 years), and the mean body mass index was 33.3 kg/m² (range, 19.6–68.9 kg/m²). Of the repairs, 27% were performed for a recurrent hernia. The mean and median size of the defect were 128 cm² and 119.5 cm² (range, 4–500 cm²), respectively. To ensure appropriate mesh overlap, the mean size of mesh was 253 cm² (range, 36–700 cm²). There were 4 conversions. The mean operative time was 117 minutes (range, 35–286 minutes). The mean length of stay was 1.9 days. There were no major abdominal complications. With a mean follow-up period of 50 months (range, 38–68 months), we have not recorded any recurrences. No mesh-related complications have been documented.

Conclusions:

The laparoscopic approach to ventral hernia repairs using Proceed mesh is associated with a low conversion rate and no major complications. At 50 months of follow-up, the recurrence rate is 0%. There were no mesh-related complications.     

A physiologic flow chamber model to define intravascular ultrasound enhancement of fibrin using echogenic liposomes

RATIONALE AND OBJECTIVES: Echogenic immunoliposomes (ELIP) for enhancement of vasoactive and pathologic components of endothelium and atherosclerosis have been developed. A physiologic flow chamber model has been developed to define intravascular ultrasound enhancement of a fibrin interface. METHODS: A IgG ELIP was used, which nonspecifically associated with fibrin, to demonstrate the suitability of this model. With varying doses of IgG ELIP, the fibrin wells were imaged at 1, 2, 4, 6, and 9 minutes. RESULTS: IgG ELIP enhanced fibrin versus saline (P < 0.005) was visible at 1 minute, lasted at least 9 minutes, and at 6 minutes the interface enhanced 27% +/- 6.1%. Enhancement was caused by increases in interface thickness and brightness. Enhancement increased with dose up to 8 mg lipid (n = 4 per time point). CONCLUSION: This model can quantitate the components of IVUS enhancement of an interface produced by ELIP. This model may allow for further development and understanding of ELIP and other targeted ultrasound contrast agents.     

A perspective on protein profiling of blood

Protein profiling of blood is going to lead to huge changes in the development of biomarkers and perhaps also in producing targets for the medical treatment of cancer. Experts in this field from Los Angeles have written an outstanding mini‐review about this topic. Renal cancer has been an area of interest to all of those involved in urological oncology, particularly from the point of view of adjuvant medical treatment either to prevent metastatic disease or to treat it. Authors from Los Angeles have produced a review of great interest on this subject. There are three other reviews on important issues. Authors from Paris have written about microsatellite instability and TCC of the upper urinary tract, and authors from Bristol have written a mini‐review about the options available when considering orthotopic bladder reconstruction. Finally, authors from Dublin have written about a significant problem in renal transplantation, delayed graft function.     

Effect of repaglinide and gliclazide on postprandial control of endogenous glucose production

The effect of repaglinide and gliclazide on postmeal suppression of endogenous glucose production (EGP) has been studied using a variable-rate tracer methodology. Groups of age-, sex-, and weight-matched type 2 diabetic subjects randomized to gliclazide or repaglinide were studied after ingesting a standard mixed meal (550 kcal; 67% carbohydrate, 19% fat, 14% protein). Plasma glucose profiles were similar in each group and markedly different from that of a nondiabetic control group. Endogenous glucose production was similar basally (3.01 +/- 0.30 vs 3.06 +/- 0.19 mg/kg per minute, gliclazide and repaglinide, respectively). After glucose ingestion, EGP declined rapidly in both the groups until 30 minutes and the greatest suppression was reached earlier in the repaglinide group [0.88 mg/kg per minute at 120 minutes vs 0.77 mg/kg per minute at 210 minutes in gliclazide group (P < .05); median time, 85 vs 195 minutes, respectively (P < .05)]. The area under the curve (30-150) for EGP was significantly greater in the gliclazide group than in the nondiabetic control group (109 +/- 11 vs 198 +/- 22 mg/kg per min 2 ; P > .02) but not significantly different in the repaglinide group (153 +/- 25 mg/kg per min 2 ; P = .17). Repaglinide has minimal physiological advantage over gliclazide, but both therapies for type 2 diabetes fall far short of correcting the endocrine and metabolic abnormalities.