Objective: Tea (Camellia sinensis Linn.; family: Theaceae) is popular as a stimulant beverage across the globe and is also utilized as a functional antioxidant in alternative medicine. This study has evaluated the impact of seasonal variation on phyto-constituents of tea.
Method: The antiproliferative potential of methanolic extracts of tea leaves collected in the rainy season (MECR) was compared with the extract of tea leaves collected in the autumn season (MECA) of the same mother plant. Evaluation of in vivo antitumor activity was carried out in adult female Swiss albino mice groups inoculated with Ehrlich ascites carcinoma (EAC) cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to compare efficacy of MECR with that of MECA in the EAC cell line. Both qualitative and quantitative tests for phytochemical constituents present in MECA and MECR were performed. Antitumor efficacy of both the extracts was determined by evaluating different tumor markers showing dose-dependent cytotoxicity.
Results: Statistically significant reduction in EAC-induced tumor was observed in MECR treated mice compared to MECA treated ones. Cell decimation was significantly higher with MECR treatment, where restoration of different parameters including tissue structures returned to normal. Moreover, gas chromatography–mass spectrometry (GC-MS) study revealed the presence of cyclobarbital and benzazulene derivative in MECR, which is thought to be a novel source of these chemicals.
Conclusions: To our knowledge, there is no report that has attempted to reveal nutritional changes in terms of efficacy and variation in anticancer constituents in tea leaves, plucked in two seasons. This study revealed a novel source of barbital and benzazulene derivative. The unique presence of cyclobarbital and benzazulene, as revealed from GC-MS data, in methanolic extract of tea leaves collected during the rainy season (MECR) may have contributed to its enhanced in vitro (adopting MTT assay) and in vivo (on EAC-infected Swiss albino mice) cytotoxicity vis-à-vis antiproliferative properties compared to methanolic extract of tea leaves collected during the autumn season (MECA). The nature of plucking leaves in the two selected seasons is different. 相似文献
High frequency micro-ultrasound (µUS) transducers with central frequencies up to 50?MHz facilitate dynamic visualization of patient anatomy with minimal disruption of the surgical work flow. Micro-ultrasound improves spatial resolution over conventional ultrasound imaging from millimeter to micrometer, but compromises depth penetration. This trade-off is sufficient during an open surgery in which the bone is removed and theultrasound probe can be placed into the surgical cavity. By fusing µUS with pre-operative imaging and tracking the ultrasound probe intra-operatively using our optical topographic imaging technology, we can provide dynamic feedback during surgery, thus affecting clinical decision making. We present our initial experience using high-frequency µUS imaging during spinal procedures. Micro-ultrasound images were obtained in five spinal procedures. Medical rationale for use of µUS was provided for each patient. Surgical procedures were performed using the standard clinical practice with bone removal to facilitate real-time ultrasound imaging of the soft tissue. During surgery, the µUS probe was registered to the pre-operative computed tomography and magnetic resonance images. Images obtained comprised five spinal decompression surgeries (four tumor resections, one cystic synovial mass). Micro-ultrasound images obtained during spine surgery delineated exquisite detailing of the spinal anatomy including white matter and gray matter tracts and nerve roots and allowed accurate assessment of the extent of decompression/tumor resection. In conclusion, tracked µUS enables real-time imaging of the surgical cavity, conferring significant qualitative improvement over conventional ultrasound. 相似文献
A combination of antioxidants (N-acetyl cysteine, α-lipoic acid, and α-tocopherol) was selected for long term oral supplementation
study in rats for protective effects on age-related mitochondrial alterations in the brain. Four groups of rats were chosen:
young control (6–7 months); aged rats (22–24 months); aged rats (22–24 months) on daily antioxidant supplementation from 18 month
onwards and young rats (6–7 months) on daily antioxidant supplementation from 2 month onwards. The brain mitochondrial functional
parameters, status of antioxidant enzymes and accumulation of oxidative damage markers were measured in the four groups of
rats. A significant decrease in complex IV activity and a loss of transmembrane potential and phosphorylation capacity along
with an increased accumulation of oxidative damage markers and compromised antioxidant enzyme status were noticed in aged
rat brain mitochondria as compared to that in young controls, but in aged rats supplemented with oral antioxidants the mitochondrial
alterations were largely prevented. Antioxidant supplementation in young rats had no effect on mitochondrial parameters investigated
in this study. The results have implications in biochemical and functional deficits of brain during aging as well as in neurodegenerative
disorders. 相似文献
BackgroundMechanical low back pain (MLBP) is a commonly encountered entity in clinical practice. Pain relief and restoration of functional capacity are management goals.Aims and objectivesTo compare the efficacy and tolerability of flupirtine, a selective neuronal potassium channel-opener (SNEPCO), with tramadol, a widely-used opioid analgesic, in MLBP.MethodsThis randomized, single-blinded, intention to treat (ITT) trial started with 240 non-steroidal anti-inflammatory drug (NSAID) intolerant patients who were prescribed either tablet flupirtine (100 mg twice daily) or capsule tramadol (50 mg twice daily), for 4 weeks. Follow-up was done on days 14, 28 and 4 weeks after treatment completion. Assessment of improvements in Indian Health Assessment Questionnaire Disability Index (Indian HAQ-DI), Visual Analogue Scale (VAS), Numerical Rating Scale (NRS) and measurement of Pain Relief Rate (PRR) were performed. Adverse events were recorded.ResultsOne hundred and seven patients receiving flupirtine and 103 receiving tramadol were analyzed on an ITT basis. Scores in Indian HAQ-DI, VAS and NRS improved significantly in both groups in the last visit, but more so with flupirtine. PRR was reasonably higher with flupirtine, [59 (55.14%)] patients experiencing significant to complete pain relief at the end of the study, compared to tramadol [41 (39.81%)]. Adverse effects were less with flupirtine [26 (24.30%) versus 41 (39.81%), p < 0.05], minimizing drop-outs.ConclusionFlupirtine has better sustained efficacy and tolerability than tramadol in MLBP. 相似文献
Polyomavirus BK (BKV) causes polyomavirus-associated nephropathy (PyVAN) and hemorrhagic cystitis (PyVHC) in renal and bone marrow transplant patients, respectively. Antiviral drugs with targeted activity against BKV are lacking. Since the antimalarial drug artesunate was recently demonstrated to have antiviral activity, the possible effects of artesunate on BKV replication in human primary renal proximal tubular epithelial cells (RPTECs), the host cells in PyVAN, were explored. At 2 h postinfection (hpi), RPTECs were treated with artesunate at concentrations ranging from 0.3 to 80 μM. After one viral replication cycle (approximately 72 hpi), the loads of extracellular BKV DNA, reflecting viral progeny production, were reduced in a concentration-dependent manner. Artesunate at 10 μM reduced the extracellular BKV load by 65%; early large T antigen mRNA and protein expression by 30% and 75%, respectively; DNA replication by 73%; and late VP1 mRNA and protein expression by 47% and 64%, respectively. Importantly, the proliferation of RPTECs was also inhibited in a concentration-dependent manner. At 72 hpi, artesunate at 10 μM reduced cellular DNA replication by 68% and total metabolic activity by 47%. Cell impedance and lactate dehydrogenase measurements indicated a cytostatic but not a cytotoxic mechanism. Flow cytometry and 5-ethynyl-2′-deoxyuridine incorporation revealed a decreased number of cells in S phase and suggested cell cycle arrest in G0 or G2 phase. Both the antiproliferative and antiviral effects of artesunate at 10 μM were reversible. Thus, artesunate inhibits BKV replication in RPTECs in a concentration-dependent manner by inhibiting BKV gene expression and genome replication. The antiviral mechanism appears to be closely connected to cytostatic effects on the host cell, underscoring the dependence of BKV on host cell proliferative functions. 相似文献
Entertainment-education is an effective health communication strategy that combines or embeds educational messages into entertainment programs to bring about social and behavior change. For years, scholars have considered how entertainment-education works. Some contemporary theories posit that entertainment-education does not engender behavior change directly but does so through mediating variables. This study adds to the literature on this topic by exploring the direct relationship between exposure and social norms instead of their relationship through behavior as a mediator. Novel to this study is the use of encoded exposure, a continuous and recognition-based measure of exposure that includes ever watching, recall, involvement, and dose in its operationalization. Using cross-sectional data from Kyunki … Jeena Issi Ka Naam Hai, an entertainment-education program in India, this exploratory analysis indicates a positive and significant relationship between encoded exposure and social norms. How can this finding be applied to future programs? Questions remain, and replication is needed, but if it is not essential to go through behavior in order to change social norms, then implications emerge for the theory and practice of entertainment-education. 相似文献