Schistosomiasis is a chronic and morbid disease of poverty affecting approximately 200 million people worldwide. Mature schistosome flatworms wander in the host's hepatic portal and mesenteric venous system where they encounter a range of blood flow conditions and geometrical confinement. However, the mechanisms that support schistosome locomotion and underlie the pathogen's adaptation to its physical environment are largely unknown. By combining microfabrication and traction force microscopy, we developed various
in vitro
assays to quantify the mechanics of locomotion of adult male
Schistosoma mansoni
in different physiologically relevant conditions. We show that in unconfined settings, the parasite undergoes two-anchor marching mediated by the coordinated action of its oral and ventral suckers. This mode of locomotion is maintained when the worm faces an external flow, to which it responds by adjusting the strength of its suckers. In geometrically confined conditions,
S. mansoni
switches to a different crawling modality by generating retrograde peristaltic waves along its body, a mechanism shared with terrestrial and marine worms. However, while the surface of most worms has backward-pointing bristles that rectify peristaltic waves and facilitate forward locomotion,
S. mansoni
has isotropically oriented tubercles. This requires tight coordination between muscle contraction and substrate friction but gives
S. mansoni
the ability to reverse its direction of locomotion without turning its body, which is likely advantageous to manoeuvre in narrow-bore vessels. We show that the parasite can also coordinate the action of its suckers with its peristaltic body contractions to increase crawling speed. Throughout this study, we report on a number of biomechanical parameters to quantify the motility of adult schistosomes (e.g. sucker grabbing strength, the rate of detachment under flow, peristaltic wave properties and traction stresses). The new series of
in vitro
assays make it possible to quantify key phenotypical aspects of
S. mansoni
motility that could guide the discovery of new drugs to treat schistosomiasis.
Schistosomiasis is a chronic and morbid disease of poverty affecting approximately 200 million people worldwide. Mature schistosome flatworms wander in the host's hepatic portal and mesenteric venous system where they encounter a range of blood flow conditions and geometrical confinement.However, the mechanisms that support schistosome locomotion and underlie the pathogen's adaptation to its physical environment are largely unknown. By combining microfabrication and traction force microscopy, we developed various in vitro assays to quantify the mechanics of locomotion of adult male S. mansoni in different physiologically relevant conditions. We show that in unconfined settings, the parasite undergoes two-anchor marching mediated by the coordinated action of its oral and ventral suckers. This mode of locomotion is maintained when the worm faces an external flow, to which it responds by adjusting the strength of its suckers. In geometrically confined conditions, S. mansoni switches to a different crawling modality by generating retrograde peristaltic waves along its body, a mechanism shared with terrestrial and marine worms. But while the surface of most worms has backward-pointing bristles that rectify peristaltic waves and facilitate forward locomotion, S mansoni has isotropically oriented tubercles. This requires tight coordination between muscle contraction and substrate friction but confers S. mansoni the ability to reverse its direction of locomotion without turning its body, which is likely advantageous to maneuver in narrow bore vessels.We show that the parasite can also coordinate the action of its suckers with its peristaltic body contractions to increase crawling speed. Throughout this study, we report on a number of biomechanical parameters to quantify the motility of adult schistosomes (e.g. sucker grabbing strength, rate of detachment under flow, peristaltic wave properties and traction stresses). The new series of in vitro assays make it possible to quantify key phenotypical aspects of S. mansoni motility that could guide the discovery of new drugs to treat schistosomiasis.
Background: Tuberculosis is the most common and deadly multisystem disease affecting the developing world. Its incidence and prevalence is on a rise in developing countries. About 10% of pulmonary tuberculosis patients present with extra-skeletal involvement of which spine is most commonly affected. It can cause neural compromise, bone destruction and spinal deformity. Material and Methods: Our study includes 30 patients with signs and symptoms of potts spine which were evaluated further by a similar protocol of investigations in last 2 years and their demographic data, clinical, radiological and microbiological findings are reported. The clinical parameters taken into consideration were fever, cough, backache and neurological complaints and any positive findings on plain radiographs of relevant spinal region and their relative presence or absence were correlated with confirmatory diagnosis on AFB culture and gene Xpert. Results: Fever & backache were most common complaints present in 19 (63.3%) of subjects. Neurological complaints were present in 15 (50%) of subjects followed by cough in 9 (30%) of subjects.22 subjects showed some finding suggestive of potts spine on plain radiograph.18 (60%) subjects were positive for MTB on culture from biopsy taken.23 (76.7%) subjects were having gene expert test positive while 7 (23%) subjects were having negative gene expert test. Total 7 out of 30 subjects had multi drug resistance (MDR) out of which 1 subject was HIV + ve while 6 were HIV -ve.2 subjects had already started the empirical ATT regimen from the peripheral centres. Conclusion: Spinal tuberculosis is still prevelant in large numbers in developing countries which remains largely undetected in most of the health centres. Our study aims to find out the role of various common clinical symptoms individually as well as combined with radiological studies as screening tests in clinical detection of spinal tuberculosis and thus faster management in its direction.
results suggest that post-transplant IL-22 administration represents a novel strategy to reduce gut GVHD by direct protection of intestinal epithelium without limiting immune function post-transplant.
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