Morphometric profile of large intestinal neuronal plexuses in normal perinatal autopsies and Hirschsprung disease.

OBJECTIVES: To derive objective values for the diagnosis of Hirschsprung disease (HSCR) from a comparison of the morphometric profile of large intestinal neuronal plexuses in normal perinatal autopsies and surgical specimens of HSCR. METHODS: A cross-sectional comparative study with 40 subjects each in (i) non-HSCR perinatal group encompassing neonates and stillborn babies beyond 30 weeks of gestation on whom autopsies were conducted and (ii) HSCR group comprising all patients clinicoradiologically diagnosed as HSCR. The morphometric assessment was done on hematoxylin-and-eosin-stained sections. KEY RESULTS: The morphometric profile in terms of average number of ganglia/linear mm of colon, interganglion distance, number of ganglion cells/ganglion, average ganglion cell length, ganglion cell nuclear area, ganglion cell nuclear diameter, nerve trunk thickness, and density has been outlined. On comparison with the neuroanatomically normal zone of HSCR, the cut-offs to identify hypertrophic nerve trunks (nerve trunk thickness of >37.85 µm) and reduced number of ganglia (number of ganglia/linear mm of colon <2.05 and interganglion distance of >229 µm) were derived. CONCLUSIONS & INFERENCES: The determined objective values, after testing on diagnostic rectal biopsies, may serve to formulate a diagnostic algorithm along with immunostaining for diagnosis of HSCR in colorectal specimens.

Local knowledge and conservation of seagrasses in the Tamil Nadu state of India.

Local knowledge systems are not considered in the conservation of fragile seagrass marine ecosystems. In fact, little is known about the utility of seagrasses in local coastal communities. This is intriguing given that some local communities rely on seagrasses to sustain their livelihoods and have relocated their villages to areas with a rich diversity and abundance of seagrasses. The purpose of this study is to assist in conservation efforts regarding seagrasses through identifying Traditional Ecological Knowledge (TEK) from local knowledge systems of seagrasses from 40 coastal communities along the eastern coast of India. We explore the assemblage of scientific and local traditional knowledge concerning the 1. classification of seagrasses (comparing scientific and traditional classification systems), 2. utility of seagrasses, 3. Traditional Ecological Knowledge (TEK) of seagrasses, and 4. current conservation efforts for seagrass ecosystems. Our results indicate that local knowledge systems consist of a complex classification of seagrass diversity that considers the role of seagrasses in the marine ecosystem. This fine-scaled ethno-classification gives rise to five times the number of taxa (10 species = 50 local ethnotaxa), each with a unique role in the ecosystem and utility within coastal communities, including the use of seagrasses for medicine (e.g., treatment of heart conditions, seasickness, etc.), food (nutritious seeds), fertilizer (nutrient rich biomass) and livestock feed (goats and sheep). Local communities are concerned about the loss of seagrass diversity and have considerable local knowledge that is valuable for conservation and restoration plans. This study serves as a case study example of the depth and breadth of local knowledge systems for a particular ecosystem that is in peril.

Axenic germination of Scutellospora erythropa and Scutellospora nigra in in vitro conditions.

Spores of Scutellospora erythropa and Scu. nigra isolated from neem rhizosphere soils from coastal regions of Chennai were tested for axenic germination in in vitro conditions. They showed positive results in media of different composition using root exudates, soil extract, thiamine HCl and inositol. The combined medium increased the spore germination in Scu. erythropa and in Scu. nigra over water agar control. The germ tube often grew up to 3.8 cm on combined media but no vegetative spores and extramatrical auxillary cells were observed during the experiment. There was significant increase in hyphal growth when the roots were introduced into the medium, 3 days after spore germination.