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551.
The effects of a beta-blocker, propranolol, on the enzyme and isoenzyme activities in the heart muscle in vitro and concomitant histopathology of the component cells of the islets of Langerhans were studied in the Wistar rats after treatment with streptozotocin and isoproterenol. The biochemical data indicated that the isoproterenol induced myocardial infarction (MI) precipitates an acute diabetic response in the rat heart. The superimposition of MI in diabetes mellitus caused significant inhibition of phosphofructokinase and hexokinase in the heart muscle. The lactate dehydrogenase depicted shifting of H-type to M-type in diabetes with or without MI. The drugs, when administered in combination, brought distinctive histopathological changes in beta-cells of the pancreatic islets including degranulation, hyalinosis and a near-total destruction; however A and D cells remained more or less unaffected. The effect of propranolol in diabetes mellitus was uncertain but in MI with or without prior diabetes, the drug inversely altered the activities of all the cardiac enzymes, besides stimulating a mild recuperation of the cells of the endocrine parenchyma. 相似文献
552.
Priyanka Grover Aseem Bhatnagar Neeraj Kumari Ananth Narayan Bhatt Dhruv Kumar Nishad Jubilee Purkayastha 《Saudi Journal of Biological Sciences》2021,28(3):1853-1859
A pigment-protein highly dominant in Spirulina is known as C-Phycocyanin. Earlier, in vitro studies has shown that C-phycocyanin is having many biological activities like antioxidant and anti-inflammatory activities, antiplatelet, hepatoprotective, and cholesterol-lowering properties. Interestingly, there are scanty in vivo experimental findings on the immunomodulatory and antioxidant effects of C-phycocyanin. This work is aimed at in vivo evaluation of the effects of C-phycocyanin on immunomodulation and antioxidant potential in Balb/c mice. Our results of in vivo toxicity, immunomodulatory and antioxidant effects of C-Phycocyanin suggests that C-phycocyanin is very safe for consumption and having substantial antioxidant potential and also possess immunomodulatory activities in Balb/c mice in a dosage dependent manner. C-phycocyanin doesn’t cause acute and subacute toxicity in the animal model (male, Balb/c mice) studied. We have reported that C-phycocyanin exhibited in vivo immunomodulation performance in this animal model. 相似文献
553.
554.
Wistar, Sprague-Dawley, and Long-Evans outbred rats, and the Fischer344 inbred strain were inoculated intranasally with 10(3) TCID50 of sialodacryoadenitis virus at approximately 9 weeks of age. Paired animals were killed at 2-day intervals post inoculation up to 2 weeks, then at 20 days. A comparison of strain susceptibility to sialodacryoadenitis virus was made using the following criteria: histopathology, immunofluorescent microscopy, serology and serum amylase activity. All four strains were susceptible to sialodacryoadenitis virus. The disease was frequently subclinical, although typical lesions were observed on histopathology. Focal bronchitis, bronchiolitis and pneumonitis were observed histologically during the acute stages of the disease. Immunohistochemistry was performed on trypsin-treated, paraffin-embedded sections, and viral antigen was readily demonstrated in salivary and lacrimal glands during the early stages of the disease. A rise in serum amylase was observed, and it was correlated with the first appearance of lesions in the salivary glands. Based on serology and immunofluorescence microscopy, the appearance of detectable antibody to sialodacryoadenitis virus, and the rate of viral clearance from infected glands, the course of the disease was similar in the four strains studied. 相似文献
555.
Swati Singh Divya Bhatt Munmun Kumar Singh Velusamy Sundaresan Sudeep Tandon Rajendra Chandra Padalia Dnyaneshwar Umrao Bawankule Ram Swaroop Verma 《化学与生物多样性》2021,18(11):e2100531
Artemisia pallens Wall. ex DC., popularly known as davana, has gained considerable attention because of its unique fragrance, high economic value, and pharmacological properties. The compositional complexity of davana essential oil (DO) has been a challenge for quality control. In this study, the chemical profile of DO was developed using polarity-based fractionation and a combination of gas chromatographic (GC-FID), hyphenated chromatographic (GC/MS), and spectroscopic (Fourier-Transform Infra-Red, 1D, 2D-Nuclear Magnetic Resonance) techniques. The analysis led to the identification of ninety-nine compounds. Major components of the DO were cis-davanone (D3, 53.0 %), bicyclogermacrene (6.9 %), trans-ethyl cinnamate (4.9 %), davana ether isomer (3.4 %), spathulenol (2.8 %), cis-hydroxy davanone (2.4 %), and trans-davanone (2.1 %). The study led to identifying several co-eluting novel minor components, which could help determine the authenticity of DO. The rigorous column-chromatography led to the isolation of five compounds. Among these, bicyclogermacrene, trans-ethyl cinnamate, and spathulenol were isolated and characterized by spectroscopic methods for the first time from DO. Pharmacological profile revealed that the treatment of DO and D3 inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6) induced by lipopolysaccharide (LPS) in primary macrophages without any cytotoxic effect after administration of their effective concentrations. The result of this study indicates the suitability of DO and D3 for further investigation for the treatment of chronic skin inflammatory conditions. 相似文献
556.
Duration and patterns of transmission of Theiler's mouse encephalomyelitis virus infection 总被引:2,自引:0,他引:2
The duration and patterns of Theiler's murine encephalomyelitis virus (TMEV) transmission were studied in eight index mice inoculated orally. Transmission was monitored by testing for seroconversion to TMEV in sentinel mice in direct contact with index mice and in other sentinel mice in contact with bedding soiled by index mice. For the first 14 weeks after inoculation, two contact sentinels were housed with each index mouse for 1 week, then replaced with two new sentinels. For the remaining 16 weeks, contact sentinels were changed monthly. All index mice transmitted TMEV continuously (weekly) for 4 to 9 weeks. Thereafter, six index mice transmitted virus intermittently. All index mice ceased transmitting TMEV 7 to 22 weeks post-inoculation. Results obtained from sentinel mice in contact with bedding soiled by index mice were 86% concordant with those using contact sentinel mice. Seven index mice were treated with cyclophosphamide or hydrocortisone 30 weeks post-inoculation. One cyclophosphamide treated mouse reinitiated virus shedding. 相似文献
557.
The pathogenesis of lesions produced by the IHD-T strain of vaccinia virus during vaccination of BALB/cAnN mice was characterized by virological, morphological, and serological methods. Infectious vaccinia virus was detected at the vaccination site for up to 16 days and was also found, to a variable extent, in lung, thymus, spleen, and liver between days 3 and 5. Viral antigen was detected at the vaccination site by avidin-biotin-linked immunoperoxidase cytochemistry, but only when viral concentrations were at least 10(5.0) log10 TCID per mg of tissue. The primary vaccination lesions were typical pocks characterized by sequential development of epidermal necrosis, vesicle formation, and ulceration and by dermal inflammation dominated by mononuclear cells. Type B inclusions were found in epidermis, but Type A inclusions were not seen. Seroconversion to vaccinia viral antigen was detected by day 8 with complement-fixation and immunofluorescence assays and by day 10 with an enzyme-linked immunosorbent assay. 相似文献
558.
559.
The purpose of this study was to determine whether stability and limb support play a similar role in governing slip outcome in gait-slip as in sit-to-stand-slip, and whether such prediction could also be derived based on measures of these variables during regular, unperturbed movements. Fifty-three and forty-one young subjects all took one recovery step following an unannounced, novel, forward slip induced in gait and in sit-to-stand, respectively. Logistic regression was used to predict recovery outcome based on preslip and reactive measures of stability and limb support across tasks. Following slip onset, all subjects in both tasks experienced rapid decay in stability and limb support (indicated by a hip descent), leading to some actual falls that could not have been predicted from regular, preslip walking. Immediately before recovery step touchdown, stability and limb support could together best predict 88.9% and 100% falls, respectively, for gait-slip and sit-to-stand-slip. Because of differences in the execution of the recovery step, stability became a better predictor of fallers in sit-to-stand-slip than in gait-slip after recovery limb touchdown. Recovery steps were highly effective in restoring stability, regardless of outcome and task. The predictive strength of stability diminished in gait-slip or reduced in sit-to-stand-slip after recovery touchdown, while limb support remained able to differentiate fallers from those who recovered in both tasks. When slip-induced instability was combined with inadequate limb support, falls were nearly inevitable in both tasks. 相似文献
560.
Photosynthetica - The effects of plant water stress imposed at vegetative, flowering, and fruiting stages of four cultivars of tomato (Lycopersicon esculentum Mill.) on net photosynthetic rate (P... 相似文献