Deciphering the mechanism of anhydrobiosis in the entomopathogenic nematode Heterorhabditis indica through comparative transcriptomics.

The entomopathogenic nematode, Heterorhabditis indica, is a popular biocontrol agent of high commercial significance. It possesses tremendous genetic architecture to survive desiccation stress by undergoing anhydrobiosis to increase its lifespan-an attribute exploited in the formulation technology. The comparative transcriptome of unstressed and anhydrobiotic H. indica revealed several previously concealed metabolic events crucial for adapting towards the moisture stress. During the induction of anhydrobiosis in the infective juveniles (IJ), 1584 transcripts were upregulated and 340 downregulated. As a strategy towards anhydrobiotic survival, the IJ showed activation of several genes critical to antioxidant defense, detoxification pathways, signal transduction, unfolded protein response and molecular chaperones and ubiquitin-proteasome system. Differential expression of several genes involved in gluconeogenesis - ß-oxidation of fatty acids, glyoxylate pathway; glyceroneogenesis; fatty acid biosynthesis; amino-acid metabolism - shikimate pathway, sachharopine pathway, kyneurine pathway, lysine biosynthesis; one-carbon metabolism-polyamine pathway, transsulfuration pathway, folate cycle, methionine cycle, nucleotide biosynthesis; mevalonate pathway; and glyceraldehyde-3-phosphate dehydrogenase were also observed. We report the role of shikimate pathway, sachharopine pathway and glyceroneogenesis in anhydrobiotes, and seven classes of repeat proteins, specifically in H. indica for the first time. These results provide insights into anhydrobiotic survival strategies which can be utilized to strengthen the development of novel formulations with enhanced and sustained shelf-life.

Malignant Course of a Metastatic Melanoma During Pregnancy: A Case Report.

Cutaneous melanoma can metastasize to any organ, including brain and spinal cord. A 27-year-old lady, four months after conception presented with generalized seizures and was diagnosed to have subarachnoid hemorrhage. Further investigation did not reveal aneurysm. She underwent right ventriculo-peritoneal shunt for hydrocephalus and MTP for unprotected radiation from CT scan. Six weeks later she came to our institution with symptoms of dorsal compression. Imaging showed multiple intradural extramedullary spinal lesions at D3-D4, D8 and D10-D11. Surgical excision of the lesions was done and histopathology was consistent with metastatic deposits from malignant melanoma which was confirmed by immunohistochemistry studies also. Her conscious level deteriorated on the second postoperative day and CT scan showed multiple small tumor emboli with evidence of right temporal bleed and diffuse cerebral edema. In spite of aggressive treatment she could not be saved. This reported case concludes that pregnancy aggravates the clinical course of metastatic melanoma.