The intra-cortical trajectory of the coeruleo-cortical projection in the rat: A tangentially organized cortical afferent

Cortical and sub-cortical lesions in the rat were used to analyze the intracortical trajectory of the noradrenergic axons, which were visualized by aldehyde-induced catecholamine histofluorescence and by immunohistochemistry using an antibody directed against rat dopamine-β-hydroxylase. Following subcortical lesions there is a slowly progressive reduction in the density of cortical noradrenergic axons, indicating that they undergo asynchronous anterograde degeneration. By 2 weeks after transection of the dorsal noradrenergic bundle, no dopamine β-hydroxylase-immunoreactive fibers are detectable in the ipsilateral cortex. Neither transection of the cingulum bundle, nor parasagittal incisions through the dorsal cortex lateral to the cingulum, diminished the noradrenergic innervation of medial or dorso-lateral cortex. A cortical lesion medial to the cingulum bundle markedly reduced the density of noradrenergic fibers in cingulate cortex caudal to the lesion, but did not affect the innervation of dorso-lateral cortex. In contrast, dorso-lateral frontal incisions and decortication (frontal lobotomy) produced a marked ipsilateral decrease in the noradrenergic fiber density throughout the remaining dorso-lateral cortex, while sparing the innervation of cingulate and infra-rhinal cortex.These results demonstrate that the dorso-lateral cortex is innervated by noradrenergic fibers in the medial forebrain bundle that reach the frontal pole, turn dorsally over the anterior portion of the forceps minor and continue caudally within the deep layers of frontal and dorso-lateral cortex, supplying the noradrenergic innervation throughout their trajectory. The medial cortex is innervated by a separate group of noradrenergic fibers that ascend through the septum, curve over the genu of the corpus callosum, and run caudally in the supracallosal stria.The present results show that the cingulum bundle is not a major intra-cortical noradrenergic pathway and does not provide branches that contribute significantly to the innervation of dorsal or lateral cortex. Thus the medial and lateral cortex can be selectively and differentially denervated of noradrenergic fibers and a coarse topographic order exists in the noradrenergic innervation of cortex. Since noradrenergic fibers travel long distances within the cortical grey matter, a small lesion of frontal cortex can have far-reaching effects on the innervation of distant, more caudal regions of cortex. The coeruleocortical projection has properties that differ from those of the best characterized cortical afferents and may be a useful model for the study of other ascending monoamine systems. The tangential, intracortical trajectory of the noradrenergic fibers would confer upon the coeruleo-cortical system the capacity to modulate neuronal activity simultaneously through a vast expanse of neocortex. A formulation of cortical organization is presented which integrates the tangential organization of the coeruleo-cortical projection with the concept of columnar organization of cortex.     

Monoliths with chiral surface functionalization for enantioselective capillary electrochromatography

The state-of-the-art in CEC enantiomer separations with monolithic capillary columns is comprehensively reviewed. The various types of monolithic columns comprising in situ organic polymer monoliths, molecularly imprinted polymer (MIP) monoliths, silica monoliths and monoliths made from particles are discussed with a focus on materials’ synthesis, chemistry and properties as well as column aspects. Monolithic MIP-type porous layer open-tubular (PLOT) columns are treated herein as well. From this survey of the literature, the authors come to the conclusion that monolithic silica capillaries appear to become the preferred column type for CEC enantiomer separations of low-molecular drugs and other chiral pharmaceuticals or chemicals.     

间二硝基苯对大鼠肝脏氧化损伤的研究

目的研究间二硝基苯（ｍ－ＤＮＢ）对肝脏的损伤并探讨其中毒机制。方法采用整体与离体实验相结合的方式对大鼠进行ｍ－ＤＮＢ染毒，观察大鼠肝脏脂质过氧化情况。结果随染毒剂量的增加和染毒时间的延长，染毒组大鼠肝脏丙二醛（ＭＤＡ）含量明显增加，呈良好的剂量－效应关系和时间－效应关系；低剂量、短时间染毒时，谷胱甘肽（ＧＳＨ）含量增加，大剂量、长时间染毒时，其含量降低；氧化型谷胱甘肽（ＧＳＳＧ）及ＧＳＳＧ／ＧＳＨ比值均随染毒剂量和时间的增加而增加；肝细胞的超氧阴离子自由基（Ｏ－２·）、羟自由基（·ＯＨ）的产生量明显增加。结论诱发脂质过氧化及产生自由基是ｍ－ＤＮＢ的主要中毒机制之一。     

Case Report of Multiple Bilobar Hepatic Arterio-Portal Fistulas Post–Liver Transplantation Managed Conservatively

Multiple intrahepatic arterio-portal fistulas are rare. The majority are isolated and occur secondary to liver trauma including iatrogenic interventions such as liver biopsy. Post–liver transplantation 18 cases have been reported, all secondary to an interventional radiological procedure. We report multiple bi-lobar arterio-portal fistulas in a liver transplant recipient recognized 1 year after transplantation. The donor died due to intracerebral bleeding following blunt head and abdominal trauma. In the present case, the etiology is not very clear. The patient was managed conservatively and to date has not required intervention.     

Antidepressants attenuate increased susceptibility to colitis in a murine model of depression

BACKGROUND & AIMS: Psychiatric factors may determine gastrointestinal health outcomes. Here, we used a model of depression based on neonatal maternal separation (MS) to identify alterations in gut physiology and to assess its association with increased sensitivity to experimental colitis in adulthood. We also examined whether antidepressant therapy attenuates the increased susceptibility to colitis. METHODS: C57BL/6 mouse pups were separated from mothers for 3 hours per day at 1-21 days of age. Maternally unseparated (US) litters served as controls. At 8 weeks of age mice were examined for changes in behavior, intestinal permeability, and sensitivity to colitis. Separate sets of MS and US mice were given either saline or the antidepressant desipramine 15 mg/kg once daily at 23-36 days of age. Testing of mice occurred at 8 weeks of age. RESULTS: Adult MS mice showed evidence of depressive-like behavior and enhanced intestinal permeability but showed no evidence of spontaneous inflammation. A more severe colitis was seen in MS compared with US mice. Antidepressant therapy improved parameters of depressive-like behavior and reduced the vulnerability to dextran sulphate sodium colitis in MS mice but had no effect on colitis in US mice. CONCLUSIONS: MS may lead to depression and increased responsiveness to stress, to impaired intestinal barrier function, and to enhanced vulnerability to colitis in adulthood. This vulnerability is reversed by antidepressant therapy. Depression increases vulnerability to intestinal inflammation. We speculate that pre-existing depression may facilitate the expression of inflammatory bowel diseases.