Development of anaplastic ependymoma in Rasmussen’s encephalitis: review of the literature and case report

Background Rasmussens encephalitis (RE) is a form of chronic encephalitis presenting with intractable seizures and progressive neurological deficits in children. The occurrence of anaplastic ependymoma in a diagnosed case of RE has not been reported in the literature.Case report We report an eight and a half year-old boy, a diagnosed case of RE, suffering from intractable right-sided focal seizures, who developed features of raised intracranial pressure during follow-up. Repeat imaging revealed left fronto-temporoparietal mass for which near-total decompression was done. Histopathology of the mass revealed anaplastic ependymoma.Conclusion The etiology of such a co-existence or development of malignancy in a pre-existing RE is yet to be completely understood. Both these entities could have a common etiology of viral- or autoimmune-mediated process, but no definite conclusion can be drawn with all the literature available at the moment.     

Renal fibrosis. Extracellular matrix microenvironment regulates migratory behavior of activated tubular epithelial cells

During progression of chronic renal disease, qualitative and quantitative changes in the composition of tubular basement membranes (TBMs) and interstitial matrix occur. Transforming growth factor (TGF)-beta(1)-mediated activation of tubular epithelial cells (TECs) is speculated to be a key contributor to the progression of tubulointerstitial fibrosis. To further understand the pathogenesis associated with renal fibrosis, we developed an in vitro Boyden chamber system using renal basement membranes that partially mimics in vivo conditions of TECs during health and disease. Direct stimulation of TECs with TGF-beta(1)/epithelial growth factor results in an increased migratory capacity across bovine TBM preparations. This is associated with increased matrix metalloproteinase (MMP) production, namely MMP-2 and MMP-9. Indirect chemotactic stimulation by TGF-beta(1)/EGF or collagen type I was insufficient in inducing migration of untreated TECs across bovine TBM preparation, suggesting that basement membrane integrity and composition play an important role in protecting TECs from interstitial fibrotic stimuli. Additionally, neutralization of MMPs by COL-3 inhibitor dramatically decreases the capacity of TGF-beta(1)-stimulated TECs to migrate through bovine TBM preparation. Collectively, these results demonstrate that basement membrane structure, integrity, and composition play an important role in determining interstitial influences on TECs and subsequent impact on potential aberrant cell-matrix interactions.     

Rate of onset of inhibition of gut-wall and hepatic CYP3A by clarithromycin

Aims

To determine the extent and time-course of hepatic and intestinal cytochrome P450 3A (CYP3A) inactivation due to the mechanism-based inhibitor clarithromycin.

Methods

Intestinal and hepatic CYP3A inhibition was examined in 12 healthy volunteers following the administration of single and multiple doses of oral clarithromycin (500 mg). Intestinal biopsies were obtained under intravenous midazolam sedation at baseline and after the first dose, on days 2–4, and on days 6–8 of the clarithromycin treatment. The formation of 1′-hydroxymidazolam in biopsy tissue and the serum 1′-hydroxymidazolam:midazolam ratio were indicators of intestinal and hepatic CYP3A activity, respectively.

Results

Intestinal CYP3A activity decreased by 64 % (p?=?0.0029) following the first dose of clarithromycin, but hepatic CYP3A activity did not significantly decrease. Repeated dosing of clarithromycin caused a significant decrease in hepatic CYP3A activity (p?=?0.005), while intestinal activity showed little further decline. The CYP3A5 or CYP3A4*1B genotype were unable to account for inter-individual variability in CYP3A activity.

Conclusions

Following the administration of clarithromycin, the onset of hepatic CYP3A inactivation is delayed compared to that of intestinal CYP3A. The time-course of drug–drug interactions due to clarithromycin will vary with the relative contribution of intestinal and hepatic CYP3A to the clearance and bioavailability of a victim substrate.     

Neutrophilic eccrine hidradenitis: A new culprit-carbamazepine

Neutrophilic eccrine hidradenitis (NEH) is a distinctive dermatosis occurring in patients with malignancy or undergoing chemotherapy. This disorder is characterized by a neutrophilic infiltrate around the eccrine glands and secretory coils, and is associated with necrosis. It must be distinguished from infections, drug eruptions, malignancies or other forms of skin diseases. As it is a self-limiting condition, establishing the diagnosis will avoid unnecessary investigations and treatment. Here we report a case of NEH in a 40-year-old woman suspected to be due to carbamazepine.KEY WORDS: Adverse cutaneous drug reaction, carbamazepine, neutrophilic eccrine hidradenitis     

In vivo antidiabetic activity and in silico studies on adenosine monophosphate-activated protein kinase (AMPK) of (2E,5E)-2,5-bis(4-hydroxy-3-methoxybenzylidene) cyclopentanone

Effect of bischalcone derivative (2E,5E)-2,5-bis(4-hydroxy-3-methoxybenzylidene) cyclopentanone (CA) on blood glucose level and lipid profile was investigated in normoglycemic and streptozotocin (STZ)-induced diabetic rats. In oral glucose and sucrose tolerance test, treatment with CA (25 mg/kg) and glidenclamide (10 mg/kg) significantly improved the glucose and sucrose tolerance in normal animals. In addition, respective treatment for 7-day resulted in significant percentage reduction in serum glucose (SG). In standardized STZ-induced diabetic rats, a single dose of CA treatment exhibited reduction in SG levels at different time intervals compared to basal levels. The lipid profile levels are restored to near-normal value of all tested parameters. The compound CA was docked into the active site of 5′-AMP (adenosine monophosphate)-activated protein kinase (PDB ID: 2OOX). The binding and docking energy were found to be ?6.9 and ?45.1 kcal/mol, respectively.