CT assessment of right colonic arterial anatomy pre and post cancer resection - a potential marker for quality and extent of surgery?

Background: There is conflicting opinion as to the optimum extent of resection for right-sided colonic cancer, which is currently graded by pathological analysis of the resected specimen. It is not known if computed tomography (CT) analysis of residual post-resection arterial stump length could be used as an alternative in vivo marker for extent of mesenteric resection. Ileocolic artery stumps have been demonstrated previously on CT after right hemicolectomy, but only in the early postoperative period. Purpose: To analyze preoperative right colonic arterial anatomy using portal venous colorectal cancer staging CT and subsequently determine if post-resection arterial stumps (a potential in vivo marker of surgical resection) could be consistently identified using routine follow-up CT scans many months after cancer resection. Material and Methods: A retrospective analysis of routine staging and follow-up CT scans for 151 patients with rightsided colorectal cancer was performed. Preoperative right colonic arterial anatomy and postoperative arterial stumps were analyzed and measured. Results: Preoperative ileocolic (98.8%), middle (94.7%), and right colic artery (23.8%) identification was comparable to catheter angiogram studies. Postoperative ileocolic stumps were consistently demonstrated (88.3%) many months (average, 2 years and 42 days) after resection and were significantly longer than expected for a standard D2 resection (paired t-test, t(127) ¼ 11.45, P 0.001). Conclusion: This is the first study to successfully demonstrate ileocolic arterial stumps many months (and years) after cancer resection using routine portal venous CT. Further prospective research should assess whether arterial stumps can be used as an in vivo marker of surgical quality and extent

Protective Mechanisms for Depression among Racial/Ethnic Minority Youth: Empirical Findings, Issues, and Recommendations

We (1) review empirical studies that report findings regarding putative protective mechanisms when exposed to risk of depression in African American and Hispanic adolescents; (2) identify key protective mechanisms for different risk contexts that garner empirical support; (3) synthesize the mechanisms identified as protective against depression among racial/ethnic minority adolescents; and (4) discuss improved methods for advancing understanding of resilience against depression in minority youth. The studies were selected from PsycINFO searches that met the following inclusion criteria: participants between 12 and 21 years of age, inclusions of racial/ethnic minority members, examining protection through an interaction with a risk factor, and outcome measures of depression, depressed mood, or depressive symptomatology. We found 39 eligible studies; 13 of which included multiple racial/ethnic groups. The following were supported as protective mechanisms, at least preliminarily, for at least one racial/ethnic group and in at least one risk context: employment, extracurricular activities, father–adolescent closeness, familism, maternal support, attending predominately minority schools, neighborhood composition, non-parent support, parental inductive reasoning, religiosity, self-esteem, social activities, and positive early teacher relationships. To investigate protective mechanisms more comprehensively and accurately across individual, social, and community levels of influence, we recommend incorporating multilevel modeling or multilevel growth curve analyses and large diverse samples

Architecture and emplacement of flood basalt flow fields: case studies from the Columbia River Basalt Group, NW USA

The physical features and morphologies of collections of lava bodies emplaced during single eruptions (known as flow fields) can be used to understand flood basalt emplacement mechanisms. Characteristics and internal features of lava lobes and whole flow field morphologies result from the forward propagation, radial spread, and cooling of individual lobes and are used as a tool to understand the architecture of extensive flood basalt lavas. The features of three flood basalt flow fields from the Columbia River Basalt Group are presented, including the Palouse Falls flow field, a small (8,890 km2, ∼190 km3) unit by common flood basalt proportions, and visualized in three imensions. The architecture of the Palouse Falls flow field is compared to the complex Ginkgo and more extensive Sand Hollow flow fields to investigate the degree to which simple emplacement models represent the style, as well as the spatial and temporal developments, of flow fields. Evidence from each flow field supports emplacement by inflation as the predominant mechanism producing thick lobes. Inflation enables existing lobes to transmit lava to form new lobes, thus extending the advance and spread of lava flow fields. Minimum emplacement timescales calculated for each flow field are 19.3 years for Palouse Falls, 8.3 years for Ginkgo,and 16.9 years for Sand Hollow. Simple flow fields can be traced from vent to distal areas and an emplacement sequence visualized, but those with multiple-layered lobes present a degree of complexity that make lava pathways and emplacement sequences more difficult to identify