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Swapnil Chouhan Kanchan Chauhan Sunita Kataria Guruprasad KN 《Journal of Plant Biology》2008,51(2):132-138
The impact of exclusion of solar UV-B (280–320 nm) and UV-A+B (280–400 nm) radiation on the root nodules was studied in soybean(Glycine max var. MACS 330). Soybean plants were grown in the tropical region of Indore (Latitude-22.4°N), India under field conditions
in metal cages covered with polyester exclusion filters that specifically cut off UV-B (<320 nm) and UV-A+B (<400 nm) radiation;
control plants were grown under ambient solar radiation. Leghemoglobin content was analyzed in the root nodules on the 50th day after emergence of seedlings. Exclusion of UV radiations significantly enhanced the leghemoglobin content in the nodules
on fresh weight basis; 25% and 45% higher amount of leghemoglobin were present in the nodules after the exclusion of UV-B
and UV-A+B radiation respectively. Analysis by native and SDS-PAGE showed high intense bands of leghemoglobin after the exclusion
of UV-A+B as compared to control. Exclusion of UV radiation also enhanced the growth of roots as well as aerial parts of the
plants. UV Exclusion increased nodulation by increase in the number and size of nodules. The results are discussed in the
light of advantage of exclusion for enhancing protein/nitrogen content in the plants. 相似文献
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Quantification of Abdominal Fat Depots in Rats and Mice during Obesity and Weight Loss Interventions
Background & Aims
Obesity is a leading healthcare issue contributing to metabolic diseases. There is a great interest in non-invasive approaches for quantitating abdominal fat in obese animals and humans. In this work, we propose an automated method to distinguish and quantify subcutaneous and visceral adipose tissues (SAT and VAT) in rodents during obesity and weight loss interventions. We have also investigated the influence of different magnetic resonance sequences and sources of variability in quantification of fat depots.Materials and Methods
High-fat diet fed rodents were utilized for investigating the changes during obesity, exercise, and calorie restriction interventions (N = 7/cohort). Imaging was performed on a 7T Bruker ClinScan scanner using fast spin echo (FSE) and Dixon imaging methods to estimate the fat depots. Finally, we quantified the SAT and VAT volumes between the L1–L5 lumbar vertebrae using the proposed automatic hybrid geodesic region-based curve evolution algorithm.Results
Significant changes in SAT and VAT volumes (p<0.01) were observed between the pre- and post-intervention measurements. The SAT and VAT were 44.22±9%, 21.06±1.35% for control, −17.33±3.07%, −15.09±1.11% for exercise, and 18.56±2.05%, −3.9±0.96% for calorie restriction cohorts, respectively. The fat quantification correlation between FSE (with and without water suppression) sequences and Dixon for SAT and VAT were 0.9709, 0.9803 and 0.9955, 0.9840 respectively. The algorithm significantly reduced the computation time from 100 sec/slice to 25 sec/slice. The pre-processing, data-derived contour placement and avoidance of strong background–image boundary improved the convergence accuracy of the proposed algorithm.Conclusions
We developed a fully automatic segmentation algorithm to quantitate SAT and VAT from abdominal images of rodents, which can support large cohort studies. We additionally identified the influence of non-algorithmic variables including cradle disturbance, animal positioning, and MR sequence on the fat quantification. There were no large variations between FSE and Dixon-based estimation of SAT and VAT. 相似文献24.
E. Kouvaras Z. Christoni I. Siasios K. Malizos G. K. Koukoulis 《Biotechnic & histochemistry》2019,94(4):283-289
Neoangiogenesis has been demonstrated in chondrosarcoma. Anti-angiogenic therapies are being tested in clinical trials for chondrosarcomas. Studies of the underlying mechanisms have been performed almost exclusively in cell lines. We immunostained 20 samples of chondrosarcoma and 20 samples of enchondromas with antibodies against hypoxia-inducible factor 1-alpha (HIF-1-alpha) and vascular endothelial growth factor (VEGF). The immunohistochemical staining of HIF-1-alpha and VEGF were highly correlated. Enchondromas were HIF-1-alpha and VEGF negative, whereas all chondrosarcoma exhibited HIF-1-alpha and VEGF immunostaining. HIF-1-alpha/VEGF double positive cases were almost exclusively chondrosarcomas with a high tumor grade. We suggest that HIF-1-alpha is a marker of malignancy in chondrosarcomas that correlates with tumor neo-angiogenesis. Our findings also suggest that a HIF-1-alpha/VEGF angiogenic pathway may exist in chondrosarcoma in vivo as in other malignant tumors. The inclusion of novel inhibitors to HIF-1-alpha and other factors may optimize anti-angiogenic interventions in chondrosarcoma. 相似文献