Evaluation of peripheral enhancement on contrast-enhanced computed tomography and corresponding pathological findings in colorectal liver metastases after preoperative chemotherapy

Purpose: To correlate peripheral enhancement on contrast-enhanced computed tomography (CE-CT) in patients with post-chemotherapy colorectal liver metastases (CRLM) with the corresponding pathological findings. Material and methods: Forty-four patients with CRLM who underwent hepatic resection after preoperative chemotherapy between 2008 and 2013 were included. Two radiologists blinded to the histopathology findings performed a consensus categorization of the marginal contrast effects of CRLM on CE-CT as follows: Group 1, smooth margin without enhancement; Group 2, smooth margin with an enhanced rim; and Group 3, fuzzy margin with/without an enhanced rim. The Kruskal-Wallis test was used to compare the imaging findings with the histological findings. Results: The percentage of infarct-like necrosis was significantly higher in those with CRLM with smooth margins than in those with CRLM with fuzzy margins (p < 0.001, r = 0.62). The percentage of viable cells was lowest in CRLM with smooth margins without enhancement (p < 0.001, r = 0.60). Conclusions: Our findings suggest that the type of necrosis is related to the nature of the margins, and the presence of residual cells is related to peripheral enhancement

Spreading of Antarctic Bottom Water examined using the CFC-11 distribution simulated by an eddy-resolving OGCM

We have investigated the spreading and pathway of Antarctic Bottom Water(AABW) using the simulated distribution of chlorofluorocarbons(CFCs) in a global eddy-resolving(1/10°) OGCM. Our goal is understanding of the processes and pathways determining the distribution of CFCs in the Southern Ocean, where much of this tracer is entrained by formation of deep and bottom water. The simu- lated high CFC-11 water reveals the newly formed AABW around the Antarctic Continent. The main source regions of AABW in the model are in the Weddell Sea(60°- 30°W ), offshore of Wilkes Land(120°- 160°E ) and in the Ross Sea(170°E -160°W ). In our model, spreading of simulated CFC-11 in the deep Southern Ocean from the newly formed AABW regions is more similar to the observed distribution than in coarse-resolution models. In the Weddell Sea, the high CFC-11 water spreads eastward with the Antarctic Circumpolar Current(ACC) and flows northward to the Argentine Basin. The high CFC-11 water from Wilkes Land joins with the high CFC-11 water from the Ross Sea. Some of the high CFC-11 water from Wilkes Land flows northward toward New Zealand. The high CFC-11 water from the Ross Sea flows eastward with the ACC along the Mid Ocean Ridge and northward to the Southeast Pacific Basin

Equatorial Pacific Subsurface Countercurrents: A Model–Data Comparison in Stream Coordinates

An isopycnal stream-coordinate analysis of velocity, transport, and potential vorticity (PV), recently applied to observations of the subsurface countercurrents (SCCs) in the equatorial Pacific Ocean, is applied here to the SCCs in a numerical general ocean circulation model, run by the Japan Marine Science and Technology Center (JAMSTEC). Each observed SCC core separates regions of nearly uniform potential vorticity: low on the equatorward side, high on the poleward side. Similar low-PV pools are found in the model, but the high-PV region poleward of the southern SCC is missing. The potential vorticity gradient in each core is weaker in the model than in observations, and relative vorticity plays only a minor role in the model. Its unusually high vertical resolution, with 55 levels, together with its weak lateral dissipation may be key factors in the JAMSTEC model\u27s ability to simulate SCCs

Potential endocrine effects of hypothalamic peptide "neurotensin" on pancreas in dogs

Effects of synthetic neurotensin on the endocrine pancreas were studied in nine normal and six hypophysectomized (10th to 14th day post-hypophysectomy) dogs. Synthetic neurotensin was administered into the superior pancreaticoduodenal artery, and plasma insulin and glucagon concentrations were measured radioimmunologically. In normal dogs, ten microgram/kg neurotensin administration brought about a mild hyperglycemic response and sharp and rapid increase of plasma insulin and glucagon concentrations in the superior pancreaticoduodenal vein. A biphasic insulin response was noted in the pancreatic vein. The results suggest that a large dose of neurotensin acts directly on the endocrine pancreas causing secretion of these hormones. In hypophysectomized dogs, basal levels of plasma insulin and glucagon were decreased and neurotensin had little effect on the endocrine pancreas even with the administration of a large dose.</p

Pathways and variability of the Antarctic Intermediate Water in the western equatorial Pacific Ocean.

In the western equatorial Pacific the low-salinity core of Antarctic Intermediate Water (AAIW) is found at about 800 m depth between potential density levels σθ = 27.2 and 27.3. The pathways of AAIW and the degradation of its core are studied, from the Bismarck Sea to the Caroline Basins and into the zonal equatorial current system. Both historical and new observational data, and results from numerical circulation model runs are used. The observations include hydrographic stations from German and Japanese research vessels, and Eulerian and Lagrangian current measurements. The model is the JAMSTEC high-resolution numerical model based on the Modular Ocean Model (MOM 2). The general agreement between results from the observations and from the model enables us to diagnose properties and to provide new information on the AAIW. The analysis confirms the paramount influence of topography on the spreading of the AAIW tongue north of New Guinea. Two cores of AAIW are found in the eastern Bismarck Sea. One core originates from Vitiaz Strait and one from St. George’s Channel, probably arriving on a cyclonic pathway. They merge in the western Bismarck Sea without much change in their total salt content, and the uniform core then increases considerably in salt content when subjected to mixing in the Caroline Basins. Hydrographic and moored current observations as well as model results show a distinct annual signal in salinity and velocity in the AAIW core off New Guinea. It appears to be related to the monsoonal change that is typically found in the near-surface waters in the region. Lagrangian data are used to investigate the structure of the deep New Guinea Coastal Undercurrent, the related cross-equatorial flow and eddy-structure, and the embedment in the zonal equatorial current system. Results from 17 neutrally buoyant RAFOS floats, ballasted to drift in the AAIW core layer, are compared with a numerical tracking experiment. In the model 73 particles are released at five-day intervals from Station J (2.5°N, 142°E), simulating currents at a moored time series station north of New Guinea. Observed and model track patterns are fairly consistent in space and season. Floats cross the equator preferably north of Cenderawasih Bay, with a maximum range in eddy-motion in this region north of New Guinea. The northward route at 135°E is also reflected in a low-salinity tongue reaching up to 3°N. At that longitude the floats seem to ignore the zonally aligned equatorial undercurrents. Farther to the east (139 145°E), however, the float observations are consistent with low-latitude bands of intermediate currents