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81.
Journal of Plant Growth Regulation - Drought poses serious threats to global crop production and its intensity is continuously soaring due to global warming. Brassica napus L. is an essential...  相似文献   
82.
Eukaryotic initiation factor 4E (eIF4E), a fundamental effector and rate limiting element of protein synthesis, binds the 7-methylguanosine cap at the 5′ end of eukaryotic messenger RNA (mRNA) specifically as a constituent of eIF4F translation initiation complex thus facilitating the recruitment of mRNA to the ribosomes. This review focusses on the engagement of signals contributing to growth factor originated maxim and their role in the activation of eIF4E to achieve a collective influence on cellular growth, with a key focus on conjuring vital processes like protein synthesis. The review invites considerable interest in elevating the appeal of eIF4E beyond its role in regulating translation viz a viz cancer genesis, attributed to its phosphorylation state that improves the prospect for the growth of the cancerous cell. This review highlights the latest studies that have envisioned to target these pathways and ultimately the translational machinery for therapeutic intervention. The review also brings forward the prospect of eIF4E to act as a converging juncture for signaling pathways like mTOR/PI3K and Mnk/MAPK to promote tumorigenesis.  相似文献   
83.
Allelochemicals are secondary metabolites which are not edible and can be used as growth regulators and bio-herbicides. The goal of current study was to assess allelopathic ability of Lantana camara (Sage-plant) flowers against weeds viz. Avena fatua (Wild oat), Euphorbia helioscopia (Sun-spurge), Chenopodium album (Goosefoot), Phalaris minor (Canary-grass), and Rumex dentatus (Knotweed). Bioassay analysis of three methanolic fractions of the Combiflash from L. camara was performed at 50%, 75% and 100% concentration using germination percentage parameters, inhibition of plumule and radicle size. The fraction II of Combiflash strongly suppressed all weeds with negligible effect on T. aestivum. Gas chromatography-mass spectroscopy was conducted for the fraction, and isolated compounds were used to perform bioassays. From fraction II GC–MS detected four methyl esters of allelopathic fatty acid viz. Methyl oleate, methyl palmitate, methyl stearate and methyl linoleate. The evaluation of physiological effects of the bioassay revealed substantial suppression of chlorophyll, antioxidant enzymes (superoxide, dismutase peroxidase) and protein material in all weeds by methyl palmitate. Bioassay activity and study of physiological parameters revealed that the effective bio-herbicidal compound in Lantana camara flowers is methyl palmitate. This is the first time that methyl palmitate (a fatty acid methyl ester) has been related to herbicidal activity in L. camara flowers. It is proposed that field studies based on hormesis research and the mechanism of action of this compound be carried out.  相似文献   
84.

Background

Hyalinizing clear cell carcinoma (HCCC) is a rare low-grade tumour of salivary glands that was first described as a distinct entity in 1994 by Milchgrub et al. EWSR1-ATF1 fusion was found to be specific for this tumour. The majority of the reported cases of HCCC arise from minor salivary glands within the oral cavity. Primary HCCC of the paranasal sinus is extremely uncommon. To our knowledge, only three cases have been reported in the English literature. Herein, we present a case of HCCC of the posterior ethmoid/maxillary sinus.

Case presentation

A 63-year-old lady who presented with a long history of epistaxis. CT scan revealed a destructive mass in the left ethmoid/posterior maxillary sinus extending to the nasal cavity. Surgical excision was done and microscopic evaluation showed a tumour composed mainly of nests of clear epithelial cells separated by fibrocellular and hyalinized septa with extensive bone destruction. The tumour cells expressed CK5/6, EMA and p63 immunohistochemically but were negative for S100 protein, PAX-8, RCC and CK7. Sinonasal renal cell–like adenocarcinomas, myoepithelial carcinoma and metastatic renal cell carcinoma were excluded by radiological and immunohistochemical studies. Fluorescence in situ hybridization analysis revealed an EWSR1 gene rearrangement. Postoperative radiation was administrated and the patient did not show recurrence or distant metastasis 4 months after the surgery.

Conclusion

Head and neck region have many tumours that demonstrate clear cell changes on histology. Thus, the differential diagnosis for HCCC is wide. Awareness of this rare entity and the possibility of it is arising in unusual location is necessary. EWSR1-AFT1 fusion, a consistent finding in HCCC, can be used to confirm the diagnosis.
  相似文献   
85.
The present study deals with technique for improving phytoremediation of trace metals from synthetic leachate in the presence of recycled waste material (crushed brick and steel slag) as substrates. It is an economic and environment-friendly approach as compared to chelators. Chelators induce adverse effects on plant growth, which might affect the phytoextraction capability. This study was conducted to compare the removal of copper and zinc by Phragmites australis and Typha latifolia with chelators (ethylenediaminetetraacetic acid ~2.5 mmol, citric acid ~2.5 mmol) and substrates (slag ~2 kg, crushed brick ~2 kg) for 21 days. Translocation of copper in T. latifolia and P. australis increased with increase in its applied concentration and this increase was higher in presence of slag as compared to crushed brick. In treatment systems with chelators, translocation decreased with increase in copper concentration. Principal component analysis revealed correlation between the removal of copper and zinc with adsorption by substrates, which statistically proved that slag and crushed brick played a significant role in treating leachate. Phragmites australis and T. latifolia with substrates was found to be equivalent to that of chelators. Phytoremediation with crushed brick and steel slag is an environment friendly, cost effective and practical approach for developing countries.  相似文献   
86.
An intracellular glucose oxidase (GOD) was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger NFCCP. The enzyme was partially purified to a yield of 28.43% and specific activity of 135 U mg(-1) through ammonium sulfate precipitation, anion-exchange chromatography, and gel filtration. The enzyme showed high specificity for D-glucose, with a K(m) value of 25 mmol L(-1). The enzyme exhibited optimum catalytic activity at pH 5.5. Optimum temperature for GOD-catalyzed D-glucose oxidation was 40 degrees C. The enzyme displayed a high thermostability having a half-life (t(1/2)) of 30 min, enthalpy of denaturation (H*) of 99.66 kJ mol(-1), and free energy of denaturation (G*) of 103.63 kJ mol(-1). These characteristics suggest that GOD from A. niger NFCCP can be used as an analytical reagent and in the design of biosensors for clinical, biochemical, and diagnostic assays.  相似文献   
87.
Preeclampsia (PE) as a pregnancy‐specific disorder is the major cause of mortality and morbidity of mothers and fetuses. This study attempts to investigate the possible association between the 2572C>A (rs4846049) and 4869C>G (rs1537514) polymorphisms in the 3′‐ untranslated region of MTHFR gene and the risk of PE. A total of 198 patients diagnosed with PE and 171 unrelated, age matched healthy pregnant women, were recruited for this case‐control study. The MTHFR 2572C>A and 4869C>G genotyping was performed by the polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) method. The CG genotype of MTHFR 4869C>G was associated with decreased risk of PE, and this genotype was found to be a protective factor for PE susceptibility. There was no significant difference in the genotypes of MTHFR 2572C>A polymorphism between PE patients and control group. The frequency of combined AC/CG genotypes of MTHFR 2572C>A and 4869C>G polymorphisms were less frequent in PE patients and were associated with a lower risk of PE. The C‐G and A‐G haplotypes of MTHFR 2572C>A and 4869C>G polymorphisms were significantly lower in PE patients. In conclusion, the CG genotype of MTHFR 4869C>G polymorphism was associated with a lower risk of PE. No association was found between MTHFR 2572C>A polymorphism and PE.  相似文献   
88.

Objective

To study the putative effects of Advanced Oxidation Protein Products (AOPPs) and Advanced Glycation End Products (AGEs) in the development and progression of cardiovascular disease (CVD).

Methodology

AGEs, AOPPs, e-NOS, lipid profile, circulating stress and inflammatory biomarkers were evaluated among fifty cardiovascular patients and fifty controls. Independent student’s t-test was done for statistical analysis.

Results

The malondialdehyde mean level in CVD patients (5.45?nmol/ml) was significantly higher than control (1.36?nmol/ml) (p value?=?0.018). Nitric oxide in CVD patients (55.72?ng/ml) was remarkably increased as compared to normal subjects (19.19?ng/ml). A significant change in the mean serum level of AGEs in CVD patients (2.74?ng/ml) and normal individuals (0.85?ng/ml) was recorded (p value?=?0.000). The AOPPs also showed significant increased levels in CVD group (132.07?ng/ml) in comparison with normal subjects (83.05?ng/ml) (p value?=?0.011). The mean eNOS serum level in CVD group (15.50?U/L) was higher than control group (11.28?U/L) (p value?=?0.004). Cardiovascular disease patients, in comparison with healthy controls, showed increased level of total cholesterol (5.48?mmol/L vs 4.45?mmol/L), triglycerides (2.59?mmol/L vs 1.24?mmol/L), and low density lipoprotein (2.47?mmol/L vs 2.31?mmol/L) along with decrease in high density lipoprotein (1.39?mmol/L vs 1.74?mmol/L). The mean MMP-11 serum levels in CVD group (98.69?ng/ml) was almost double of control group (45.60?ng/ml) (p value?=?0.017). The mean serum level of TNF-α and IL1-α were 32.16?pg/ml and 6.64?pg/ml in CVD patient. The significant decreasing trend of SOD (p value?=?0.041), CAT (p value?=?0.018), GSH (p value?=?0.036) and GRx (p value?=?0.029) but increasing drift of GPx (0.023) level was observed in CVD patients.

Conclusion

This study provides strong evidence that CVD patients presented with elevated oxidative stress, enhanced inflammation and lipid profile in their serum. Therefore, the study strongly approves that AGEs, AOPPs, inflammatory and lipoxidative biomarkers hold predictive potential in causing and aggravating the disease, thus by controlling these factors CVD progression can be inhibited.  相似文献   
89.
90.

Background

Cancer patients when treated with different chemotherapeutic drugs often develop mild to severe sight threatening diseases during or after chemotherapy. The mechanism involved in the pathogenesis of ocular toxicities is poorly understood. Oxidative stress, inflammation and MMPs (angiogenic factor) are involved in the progression of chemotherapy related ocular disorders.

Materials and methods

The concentration of oxidative stress markers such as MDA, NO and levels of different antioxidant molecules such as SOD, CAT, GSH, GPx, GPr, VIT A, VIT E and VIT C present in the serum of chemotherapy treated patients (n?=?50) and in normal persons (n?=?20) were estimated by the direct spectrophotometric method while the concentration of TNF-α and MMP-9 activity were determined using human TNF-α and MMP-9 ELISA kits.

Results

The concentration of SOD and CAT (0.356?±?0.05?μg/dl and 1.26?±?0.01?μmol/mol of protein) was significantly lower as compared to that (1.09?±?0.03?μg/dl and 3.99?±?0.04?μmol/mol of protein) in controls. The levels of GPx (0.06?±?0.01?mmol/dl) in the cancer patients were much lower than those in the controls (0.78?±?0.06?mmol/dl). Lower level of GSH (0.96?±?0.003?μg/dl) in serum of the diseased group was observed as compared to healthy group (7.26?±?1.40?μg/dl). The level of Vit A, Vit C and Vit E was lower in systemic circulation of cancer patients (109.99?±?6.35?μg/ml, 1.26?±?0.36?μg/ml and 1.29?±?0.191?μg/ml) as compared to control subjects (166.35?±?14.26?μg/ml, 3.25?±?0.099?μg/ml and 6.354?±?2.26?μg/ml) respectively. The concentration of nitric oxide was significantly higher in the cancer patients (45.26?±?6.35?ng/ml) than that in the normal subjects (16.35?±?3.26?ng/ml). The higher concentration of MDA (8.65?±?3.26?nmol/ml) was observed in the patients than normal ones (1.254?±?0.065?nmol/ml). The quantity of TNF-α was significantly higher in chemotherapy treated patients (32.68?±?4.33?pg/ml) as compared to the control group (20.979?±?1.98?pg/ml). Significantly higher concentration of MMP-9 (40.26?±?3.26?ng/ml) was observed in the cancer patients than the controls (7.256?±?1.95?ng/ml).

Conclusion

Lower levels of antioxidant enzymes and non-enzymatic small molecules and higher levels of oxidative stress and inflammatory clinical parameters such as NO, MDA, TNF-α and MMP-9 may be involved in the pathogenesis of systemic chemotherapy related ocular complications such as cataract, glaucoma, blepharitis, retinitis pigmentosa, macular degeneration, pterygium and retinal degeneration.  相似文献   
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