The role of intraoperative hyperspectral imaging (HSI) in colon interposition after esophagectomy.

BACKGROUND: Colon conduit is an alternative approach to reconstructing the alimentary tract after esophagectomy. Hyperspectral imaging (HSI) has been demonstrated to be effective for evaluating the perfusion of gastric conduits, but not colon conduits. This is the first study to describe this new tool addressing image-guided surgery and supporting esophageal surgeons to select the optimal colon segment for the conduit and anastomotic site intraoperatively. PATIENTS AND METHODS: Of 10 patients, eight who underwent reconstruction with a long-segment colon conduit after esophagectomy between 01/05/2018 and 01/04/2022 were included in this study. HSI was recorded at the root and tip of the colon conduit after clamping the middle colic vessels, allowing us to evaluate the perfusion and appropriate part of the colon segment. RESULTS: Anastomotic leak (AL) was detected in only one (12.5%) of all the enrolled patients (n = 8). None of the patients developed conduit necrosis. Only one patient required re-anastomosis on postoperative day 4. No patient needed conduit removal, esophageal diversion, or stent placement. There was a change in the anastomosis site to proximal in two patients intraoperatively. There was no need to change the side of colon conduit intraoperatively in any patient. CONCLUSION: HSI is a promising and novel intraoperative imaging tool to objectively assess the perfusion of the colon conduit. It helps the surgeon to define the best perfused anastomosis site and the side of colon conduit in this type of operation.

Fluorescent analogs of peptoid-based HDAC inhibitors: Synthesis, biological activity and cellular uptake kinetics.

Fluorescent tagging of bioactive molecules is a powerful tool to study cellular uptake kinetics and is considered as an attractive alternative to radioligands. In this study, we developed fluorescent histone deacetylase (HDAC) inhibitors and investigated their biological activity and cellular uptake kinetics. Our approach was to introduce a dansyl group as a fluorophore in the solvent-exposed cap region of the HDAC inhibitor pharmacophore model. Three novel fluorescent HDAC inhibitors were synthesized utilizing efficient submonomer protocols followed by the introduction of a hydroxamic acid or 2-aminoanilide moiety as zinc-binding group. All compounds were tested for their inhibition of selected HDAC isoforms, and docking studies were subsequently performed to rationalize the observed selectivity profiles. All HDAC inhibitors were further screened in proliferation assays in the esophageal adenocarcinoma cell lines OE33 and OE19. Compound 2, 6-((N-(2-(benzylamino)-2-oxoethyl)-5-(dimethylamino)naphthalene)-1-sulfonamido)-N-hydroxyhexanamide, displayed the highest HDAC inhibitory capacity as well as the strongest anti-proliferative activity. Fluorescence microscopy studies revealed that compound 2 showed the fastest uptake kinetic and reached the highest absolute fluorescence intensity of all compounds. Hence, the rapid and increased cellular uptake of 2 might contribute to its potent anti-proliferative properties.

Diagnostic reference levels in pediatric radiology in Austria.

BACKGROUND: Because of the higher sensitivity to radiation in children, optimization plays an essential role in pediatric radiology. Diagnostic reference levels are a helpful tool to optimize patient dose for standard radiographic procedures. METHODS: A nationwide survey was conducted to determine doses and variation in average dose applied to children for standard X-ray examinations. Dose values for chest, skull and abdomen X-ray procedures were determined for newborns, 1, 5, 10 and 15 year olds. RESULTS: Third quartiles of patient doses are provided and compared to European, British and German reference values. Variation in average doses between hospitals (i.e., ratio of maximal to minimal applied average dose) for the same age and examination was found to be typically a factor of eight. Ratios of maximal to minimal applied doses to individual patients were found to be approximately a factor of six higher than variations of average doses between clinics. CONCLUSIONS: While average patient doses indicate the use of good radiological practice in general, variance in average doses applied by different hospitals indicate that audit of dose with respect to reference values will provide guidance for optimization. Such practice should result in lowering doses for pediatric examinations.

Bone mineral density measurement with dental quantitative CT prior to dental implant placement in cadaver mandibles: pilot study.

PURPOSE: To correlate torque forces during insertion of screw-type dental implants with bone mineral density (BMD) values determined preoperatively. MATERIALS AND METHODS: Dental quantitative computed tomography (CT) was performed with simultaneous imaging of five postmortem mandibles and a calibration standard containing defined concentrations of calcium hydroxyapatite. CT numbers were converted to local BMD values by assuming a linear relationship (BMD = a x HU + b), where a and b are calibration coefficients. The a, b, P, and t values, correlation coefficients, and standard errors were calculated. Dental implants (n = 25) were set, and insertion torques were recorded. BMD was determined at the implantation site and correlated with torque forces recorded during implant insertion. Calibration coefficients derived for specimens were compared with those derived for actual patients. RESULTS: Calibration coefficients (at 120 kV) for the postmortem specimens were a = 0.760 +/- 0.03 (mean +/- SD) and b = 2.8 +/- 3.7 and for the patients were a = 0.804 +/- 0.06 and b = 5.2 +/- 4.2. Calibrated BMD values at the location of dental implants exhibit a significant correlation (R(2) = 0.83, P <.001) with insertion torques on the basis of a second-order model, which yields torque = (0.0055 x BMD + 0.73)(2) for the implants used and the surgical technique applied. CONCLUSION: Correlation exists between BMD measured with dental quantitative CT and the insertion torque of dental implants.