Malignant Transformation in Porokeratosis Ptychotropica: A Systematic Review.

Porokeratosis ptychotropica (PP) is a rare and unusual variant of porokeratosis. There is a dearth of information on the natural history, epidemiology, and optimal treatment options. This study aimed to characterize the worldwide distribution, epidemiology, clinical features, and treatments attempted for all reported cases of porokeratosis ptychotropica. A total of 59 cases of porokeratosis ptychotropica have been reported, with most cases originating from the United States. The median age of patients affected with porokeratosis ptychotropica was 49 years. The most involved body locations are the buttocks and gluteal cleft. The risk of malignant transformation in porokeratosis ptychotropica is approximately 1.7% but there is significant bias in estimating rare occurrences in rare diseases. In conclusion, PP is an important but under-recognized variant of porokeratosis, with a likely low risk of malignant transformation. The best available treatment modality remains uncertain; however, the use of topical lovastatin/cholesterol cream appears promising. Long-term surveillance appears prudent for porokeratosis ptychotropica due to a risk of cancerization.

Left atrial appendage mass.

Left atrial (LA) masses are known to be associated with peripheral embolization. Accurate identification of etiology is crucial because treatment strategies may differ. We present the case of a young woman, who was initially diagnosed with a LA thrombus and anticoagulated. The diagnosis was revised to a primary cardiac tumor after review of the echocardiographic findings. Surgical excision revealed an atrial myxoma in an unusual location.

The orphan G protein-coupled receptor GPR40 is activated by medium and long chain fatty acids.

GPR40 is a member of a subfamily of homologous G protein-coupled receptors that include GPR41 and GPR43 and that have no current function or ligand ascribed. Ligand fishing experiments in HEK293 cells expressing human GPR40 revealed that a range of saturated and unsaturated carboxylic acids with carbon chain lengths greater than six were able to induce an elevation of [Ca(2+)](i), measured using a fluorometric imaging plate reader. 5,8,11-Eicosatriynoic acid was the most potent fatty acid tested, with a pEC(50) of 5.7. G protein coupling of GPR40 was examined in Chinese hamster ovary cells expressing the G alpha(q/i)-responsive Gal4-Elk1 reporter system. Expression of human GPR40 led to a constitutive induction of luciferase activity, which was further increased by exposure of the cells to eicosatriynoic acid. Neither the constitutive nor ligand-mediated luciferase induction was inhibited by pertussis toxin treatment, suggesting that GPR40 was coupled to G alpha(q/11.) Expression analysis by quantitative reverse transcription-PCR showed that GPR40 was specifically expressed in brain and pancreas, with expression in rodent pancreas being localized to insulin-producing beta-cells. These data suggest that some of the physiological effects of fatty acids in pancreatic islets and brain may be mediated through a cell-surface receptor.