The pathophysiology of the Tuberculin reaction is explained thus: M. Tuberculi are engulfed by macrophages after being identified as foreign, but due to a self- preserving mechanism peculiar to TB it is able to block the fusion of the phagosome within which it is existing with the lysosome which would destroy it. So it can continue existing and replicating within the immune cell designed to destroy it. After several weeks, the immune system somehow [ mechanism as yet unexplained] ramps up and, on stimulation with IFN-gamma, the macrophages become capable of killing M. Tuberculi by forming phagolysosomes and nitric oxide radicals. However unfortunately the hyper-activated macrophages secrete TNF which recruits multiple monocytes into the battle. These cells differentiate into epithelioid histiocytes which wall off the infected cells, but at the cost of significant inflammation and local damage 'Biofertilizer' is a substance which contains living microorganisms which, when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Biofertilizers add nutrients through the natural processes of Nitrogen fixation , solubilizing phosphorus, and stimulating plant growth through the synthesis of growth promoting substances. Biofertilizers can be expected to reduce the use of chemical fertilizers and pesticides. The microorganisms in biofertilizers restore the soil's natural nutrient cycle and build soil organic matter. Through the use of biofertilizers, healthy plants can be grown while enhancing the sustainability and the health of soil. Since they play several roles, a preferred scientific term for such beneficial bacteria is plant-growth promoting rhizobacteria (PGPR). Therefore, they are extremely advantageous in enriching the soil fertility and fulfilling the plant nutrient requirements by supplying the organic...
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