Recanalization of systemic venous baffles by radiofrequency perforation and stent implantation.

Complete transposition of the great arteries has been historically managed by the Mustard (atrial switch) operation. This procedure is associated with longterm complications such as baffle occlusion, which also precludes the insertion of a permanent transvenous pacemaker. Transcatheter techniques have allowed the successful angioplasty and stenting of stenotic baffles but complete occlusions continue to pose a therapeutic challenge. We report the use of a novel technique, a radiofrequency perforation wire for the management of complete occlusion of systemic venous baffles post-Mustard operation.     

The management of gout in Africa: challenges and opportunities

Clinical Rheumatology - The rise in non-communicable diseases in Africa presents challenges for health systems that are burdened by infectious diseases. Gout is one of those diseases that has seen...     

Mechanism of acute pancreatitis exacerbation by enteral bile-pancreatic juice exclusion.

Using an original model, the donor rat model, we previously showed that bile-pancreatic juice exclusion from gut exacerbates ligation-induced acute pancreatitis. Here, we examine the mechanism by which bile-pancreatic juice exclusion from gut exacerbates acute pancreatitis. In the first part of the study we test the hypothesis that Na taurocholate and trypsin are components of bile-pancreatic juice that exacerbate acute pancreatitis when excluded. Our experiments show that combined replacement of Na taurocholate and trypsin ameliorates acute pancreatitis. In the second part of the study we test the hypothesis that bile-pancreatic juice exclusion from gut exacerbates acute pancreatitis via combined CCK-A and cholinergic receptor pathways. Our experiments show that combined CCK-A and cholinergic receptor blockade significantly ameliorates acute pancreatitis while blockade of either receptor alone does not. We conclude that bile-pancreatic juice exclusion-induced exacerbation of ligation-induced acute pancreatitis involves a neurohormonal duodenal response to exclusion of trypsin and Na taurocholate resulting in acinar cell hyperstimulation via combined CCK-A and cholinergic receptor-mediated pathways.     

Glia Maturation Factor Deficiency Suppresses 1-Methyl-4-Phenylpyridinium-Induced Oxidative Stress in Astrocytes

Inflammation is closely intertwined with pathogenesis of Parkinson’s disease (PD). Increasing evidence suggests that inhibition of glia-mediated inflammation might represent a promising therapeutic target for PD. Glia maturation factor (GMF), an inflammatory protein, predominantly localized in astrocytes is previously isolated, sequenced and cloned in our laboratory. In the present investigation, we demonstrate that GMF-deficiency in astrocytes upregulates the antioxidant status and limit the extent of lipid peroxidation and production of reactive oxygen species (ROS) along with diminished nuclear factor-κB-mediated inflammatory responses in 1-methyl-4-phenylpyridinium (MPP⁺)-induced toxicity. Primary astrocytes obtained from wild-type (Wt) and GMF-deficient (GMF-KO) mice were treated with 5, 10, and 20 μM MPP⁺ for 24, 48, and 72 h in vitro. Our results show decreased release of ROS and increased level of glutathione in astrocytes obtained from GMF-KO mice when compared to astrocytes derived from Wt mice following MPP⁺ treatment. Additionally, we found decreased activity of NF-κB, and reduced levels of proinflammatory tumor necrosis factor- α, interleukin-1β (IL-1β), IL-17, IL-33, and chemokine (C–C motif) ligand 2 (CCL2) in GMF-KO astrocytes when compared to Wt astrocytes. Our overall results suggest that GMF-KO astrocytes are significantly resistant to MPP⁺ toxicity when compared to Wt astrocytes.     

Bile-pancreatic juice exclusion increases p38MAPK activation and TNF-alpha production in ligation-induced acute pancreatitis in rats.

Acute pancreatitis is associated with stress kinase activation and cytokine production. We hypothesize that bile-pancreatic juice exclusion activates p38(MAPK) and induces TNF-alpha production in ligation-induced acute pancreatitis. We compared rats with 1-3 h of duct ligation, duct ligation with duodenal bile-pancreatic juice replacement from a donor rat, and sham operation. Pancreatic homogenates were analyzed as follows: (a) Immunoblots using phospho-specific p38(MAPK) antibody showed increased p38(MAPK) activation after ligation that was inhibited by bile-pancreatic juice replacement. (b) Immune-complex kinase assay using ATF-2 as substrate showed increased p38(MAPK) activation after ligation that was subdued by bile-pancreatic juice replacement. (c) ELISA showed increased pancreatic TNF-alpha production after ligation that was significantly ameliorated by bile-pancreatic juice replacement. CONCLUSION: Bile-pancreatic juice exclusion from gut increases p38(MAPK) activation and TNF-alpha production in this experimental model. Our findings support our central hypothesis that bile-pancreatic juice exclusion exacerbates cell stress and acute inflammation in ligation-induced acute pancreatitis.