Forest Research Institute

About: Forest Research Institute is a facility organization based out in Dehra Dūn, India. It is known for research contribution in the topics: Population & Forest management. The organization has 5320 authors who have published 7625 publications receiving 185876 citations.

Mast cell‐mediated apoptosis of endothelial cells in vitro: A paracrine mechanism involving TNF‐α‐mediated down‐regulation of bcl‐2 expression

Abstract: Degranulated mast cells are present in the subendothelial space of eroded (de-endothelialized) coronary atheromas Upon degranulation, mast cells secrete into the surrounding tissue an array of preformed and newly synthesized mediators, including proapoptotic molecules, such as chymase and TNF-alpha In a co-culture system involving rat serosal mast cells and rat cardiac (microvascular) endothelial cells, we could show, by means of competitive RT-PCR, immunoblotting, immunocytochemistry, annexin staining, flow cytometry, and DNA-laddering, that stimulation of mast cells with ensuing degranulation rapidly (within 30 min) down-regulated the expression of both bcl-2 mRNA and protein, with subsequent induction of apoptosis in the endothelial cells The major effect of bcl-2 down-regulation resided in the exocytosed granule remnants, a minor effect also being present in the granule remnant-free supernatant No significant changes were observed in the expression levels of the pro-apoptotic protein, bax The mast cell-mediated apoptotic effect was partially (70%) dependent on the presence of TNF-alpha and involved the translocation of cytochrome C from mitochondria into cytoplasm These results are the first to show that one of the cell types present in the atherosclerotic plaques, namely the mast cell, by releasing both granule-remnant-bound and soluble TNF-alpha, may contribute to the erosion of atherosclerotic plaques by inducing apoptosis in adjacent endothelial cells Published 2003 Wiley-Liss, Inc

Identifying the tree species compositions that maximize ecosystem functioning in European forests

Abstract: 1. Forest ecosystem functioning generally benefits from higher tree species richness, but variation within richness levels is typically large. This is mostly due to the contrasting performances of ...

The mast cell : a potential link between inflammation and cellular cholesterol deposition in atherogenesis

Abstract: Mast cells are present in the arterial intima, the site of atherogenesis. In fatty streaks (the initial stage of atherogenesis) some of these cells are detected in the close vicinity of cholesterol-loaded macrophage foam cells. To ascertain whether mast cells could be involved in the formation of foam cells, a model system was developed in which isolated rat serosal mast cells were incubated with mouse peritoneal macrophages in a medium enriched with either low density lipoproteins (LDL) or high density lipoproteins (HDL3). Stimulation of the mast cells was found to induce 50-fold enhancement of LDL uptake by the macrophages. When stimulated, mast cells exocytose their secretory granules, which lose their membranes in the process. The granules then come in contact with the medium, which dissolves their histamine, a fraction of their heparin proteoglycans and all their chondroitin sulphate proteoglycans, leaving insoluble 'granule remnants'. These remnants consist of neutral proteases embedded in a heparin proteoglycan matrix. Some of the LDL particles in the incubation medium bind to this matrix, become degraded by the matrix-bound proteases, and fuse into larger particles on the surfaces of the remnants. These LDL particles are ingested by the macrophages as they phagocytose the remnants. Simultaneously, the soluble heparin proteoglycans interact with other LDL particles, forming insoluble complexes which are also phagocytosed by the macrophages. Cholesterol from the phagocytosed LDL particles ultimately becomes esterified in the macrophages, with formation of foam cells. In addition, mast cells block the removal of cholesterol from the foam cells: the remnant enzymes proteolyse HDL particles, so lessening their ability to induce efflux of cholesterol from the foam cells. These observations suggest that mast cells play an active role in the intracellular deposition of cholesteryl esters that is characteristic of early atherosclerotic lesions.

Maintenance of long-term experiments for unique insights into forest growth dynamics and trends: review and perspectives

Abstract: In this review, the unique features and facts of long-term experiments are presented. Long-term experimental plots provide information of forest stand dynamics which cannot be derived from forest inventories or small temporary plots. Most comprise unthinned plots which represent the site specific maximum stand density as an unambiguous reference. By measuring the remaining as well as the removed stand, the survey of long-term experiments provides the total production at a given site, which is most relevant for examining the relationship between site conditions and stand productivity on the one hand and between stand density and productivity on the other. Thus, long-term experiments can reveal the site-specific effect of thinning and species mixing on stand structure, production and carbon sequestration. If they cover an entire rotation or even the previous and following generation on a given site, they reveal a species’ long-term behaviour and any growth trends caused by environmental changes. Second, we exploit the unique data of European long-term experiments, some of which have been surveyed since 1848. We show the long-term effect of different density regimes on stand dynamics and an essential trade-off between total stand volume production and mean tree size. Long-term experiments reveal that tree species mixing can significantly increase stand density and productivity compared with monospecific stands. Thanks to surveys spanning decades or even a century, we can show the changing long-term-performance of different provenances and acceleration of stand production caused by environmental change, as well as better understand the growth dynamics of natural forests. Without long-term experiments forest science and practice would be not in a position to obtain such findings which are of the utmost relevance for science and practice. Third, we draw conclusions and show perspectives regarding the maintenance and further development of long-term experiments. It would require another 150 years to build up a comparable wealth of scientific information, practical knowledge, and teaching and training model examples. Although tempting, long-term experiments should not be sacrificed for cost-cutting measures. Given the global environmental change and the resulting challenges for sustainable management, the network of long-term experiments should rather be extended regarding experimental factors, recorded variables and inter- and transdisciplinary use for science and practice.