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21.

Matrix metallopeptidase 2 (MMP-2) and matrix metallopeptidase 9 (MMP-9) are involved in the breakdown of extracellular matrix in normal physiological processes as well as in disease processes, such as cancer metastasis. We conducted this work to study the role of MMP-2 and MMP-9 in breast cancer by measuring their plasma concentrations before and after surgery. Also, to examine if their levels can reflect the stage of disease and prognosis. Forty-eight breast cancer patients and 13 patients with benign breast diseases were included in the study. MMP-2 and MMP-9 levels were measured by ELISA and semi-quantitative real-time PCR. MMP-2 and MMP-9 levels in plasma were determined by ELISA immediately before surgery and during 6 to 12 months after curative surgery. We observed a significant increase in the level of MMP-9 mRNA expression in breast cancer patients in comparison to their normal breast tissues and to tissues of benign breast disease. In all TNM tumor stages, the plasma levels of MMP-2 and MMP-9 were increased significantly before curative surgery in the studied patients with breast carcinoma and decreased significantly after surgery. Both MMP-2 and MMP-9 may be used as a possible marker for follow-up or as a marker that reflects the response of the disease to treatment.

  相似文献   
22.
α-Synuclein (α-Syn) is a protein implicated in the pathogenesis of Parkinson''s disease (PD). It is an intrinsically disordered protein that binds acidic phospholipids. Growing evidence supports a role for α-Syn in membrane trafficking, including, mechanisms of endocytosis and exocytosis, although the exact role of α-Syn in these mechanisms is currently unclear. Here we investigate the associations of α-Syn with the acidic phosphoinositides (PIPs), phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2). Our results show that α-Syn colocalizes with PIP2 and the phosphorylated active form of the clathrin adaptor protein 2 (AP2) at clathrin-coated pits. Using endocytosis of transferrin as an indicator for clathrin-mediated endocytosis (CME), we find that α-Syn involvement in endocytosis is specifically mediated through PI(4,5)P2 levels on the plasma membrane. In accord with their effects on PI(4,5)P2 levels, the PD associated A30P, E46K, and A53T mutations in α-Syn further enhance CME in neuronal and nonneuronal cells. However, lysine to glutamic acid substitutions at the KTKEGV repeat domain of α-Syn, which interfere with phospholipid binding, are ineffective in enhancing CME. We further show that the rate of synaptic vesicle (SV) endocytosis is differentially affected by the α-Syn mutations and associates with their effects on PI(4,5)P2 levels, however, with the exception of the A30P mutation. This study provides evidence for a critical involvement of PIPs in α-Syn–mediated membrane trafficking.  相似文献   
23.
Chronic venous ulcer (CVU) is a major cause of chronic wounds of lower extremities and presents a significant financial and resource burden to health care systems worldwide. Defects in the vasculature, matrix deposition, and re-epithelialization are the main histopathological changes believed to impede healing. Supplementation of the amino acid arginine that plays a crucial role in the interactions that occur during inflammation and wound healing was proven clinically to improve acute wound healing probably through enhancing activity of inducible arginase (AI) locally in the wounds. However, the possible mechanism of arginine action and the potential beneficial effects of AI/arginine in human chronic wounds remain unclear. In the present study, using biopsies, taken under local anesthesia, from adult patients (n = 12, mean age 55 years old) with CVUs in lower extremities, we investigated the correlation between AI distribution in CVUs and the histopathological changes, mainly proliferative and vascular changes. Our results show a distinct spatial distribution of AI along the ulcer in the epidermis and in the dermis with the highest level of expression being at the ulcer edge and the least expression towards the ulcer base. The AI cellular immunoreactivity, enzymatic activity, and protein levels were significantly increased towards the ulcer edge. Interestingly, a similar pattern of expression was encountered in the proliferative and the vascular changes with strong correlations between AI and the proliferative activity and vascular changes. Furthermore, AI cellular distribution was associated with increased proliferative activity, inflammation, and vascular changes. Our findings of differential expression of AI along the CVU base, edge, and nearby surrounding skin and its associations with increased proliferative activity and vascular changes provide further support to the AI implication in CVU pathogenesis. The presence of high levels of AI in the epidermis of chronic wounds may serve as a molecular marker of impaired healing and may provide future targets for therapeutic intervention.  相似文献   
24.
Field evaluation of some botanical formulations like Neem Azal T/S, Neem Azal T/S + TS/fort and petroleum ether extract of Curcuma longa for the management of different pests attacking broad bean crop in a new reclaimed area at El- Noubaria and under storage conditions has been carried out. All tested formulations could be considered efficient in controlling Aphis craccivora infesting broad bean under field conditions. As to the leafminer, the number of living Liriomyza trifolii larvae decreased significantly compared to non-treated control. The number of living larvae continued to decrease until seven days post-treatment after which an increase in their number was noticed after 14 days post-treatment. Neem Azal T/S + additive (TS/fort) ranked first in comparison to other treatments for the control of aphids and leafminers attacking broad bean in the field either by killing, deterrent or antifeedant effect. The yield of treated crop increased significantly in comparison to the control. Another spray was used before harvesting the crop with the same formulations for protection of the stored crop. Neem Azal T/S with adjuvant (TS/fort) protected broad bean seeds from weevil attack for one year. Petroleum ether extract of C. longa could protect the stored crops for two months only. The percentage weight loss in one kg stored seeds treated in the field with Neem formulation + adjuvant was very small compared with those seeds treated with petroleum ether extract of C. longa and control.  相似文献   
25.
The APIZYM system of detection of enzymes was proven to be useful in the differentiation of 15 European and Egyptian isolates of S. cepivorum, the incitant of onion white rot. The tested isolates produced alkaline phosphatase, esterase (c4), esterase lipase (c8), leucine arylamidase, valinearylamidase, trypsine, α-chymatrypsin, acid phosphatase, naphthol-AS-B1-phosphohydrolase, ß-galactosidase, ß-glucutronidase, α-glucosidase, ß-glucosidase and N-acetyl-ß-glucosaminidase and did not produced lipase (c14), crystine arylamidase, trypsine, ß-glucutronidase, α-mannosidase and α-fucosidase. According to enzyme activity, isolates can be divided into four groups (G). The differences between groups were in the activity of the enzymes α-chymotrypsin and α-glucosidase. The tested European isolates and the Egyptian isolates No.6 of the pathogen were in G1 and G2; however the rest of the Egyptian isolates were in G3 and G4.  相似文献   
26.
The biological activities of two species of bacteria isolated from soil of cotton fields identified as Bacillus subtilis strain NRC313 (BS NRC313) and Bacillus thuringiensis strain NRC335 (BT NRC335) were evaluated against the third larval instar of the cotton leafworm, Spodoptera littoralis (Boisd.). The different entomopathogenic bacteria of BS NRC313and BT NRC335 contained 10 × 108 cell/ml, and caused mortality of 100 and 97.3% for the above mentioned strains, respectively. Concentrations of 2.5 × 108 to 10 × 108 cell/ml of strains BS NRC313 and BT NRC335 were applied to the larvae: LC50 were 3.3 × 108 and 3.9 × 108 cell/ml respectively. The influence of exposure to toxin concentrations manifested in terms of decreasing the adult emergence and prolongation of the generation period. The percentage of larvae that survived and succeeded to pupate increased by decreasing the concentration. The longevity of adult emergence that resulted from larvae treated with Bacillus subtilis were 6.0 ± 0.51 and 9.0 ± 0.63 days at 5 × 108 and 2.5 × 108 cell/ml, respectively compared with 9.8 ± 0.47 in control. The results indicated that Bacillus subtilis was more potent than Bacillus thuringiensis. Field applications of B. thuringiensis, B. subtilis and Reldan achieved 55.6, 67.4 and 89.4% reduction of the cotton leafworm larvae Spodoptera littoralis in clover plants under field conditions.  相似文献   
27.
The fumigant effect of Mentha piperita and Ocimum basilicum oils and their mixture against adults and eggs of Callosobruchus chinensis (L.) was evaluated. Bioassay experiments showed that Ocimum basilicum oil was significantly effective against adult and egg stage which was the least effective. However, in the fumigant toxicity experiments against adult stage, Ocimum basilicum oil at a dose of 1.0 μl/38.5 ml air caused 100% mortality (LC50 = 1.88), the mixture of both oils at a dose of 6.0 μl/38.5 ml air caused 100% mortality (LC50 = 10.3) and Mentha piperita oil at a dose of 80.0 μl/38.5 ml air caused 80.0% mortality (LC50 = 41.224) during a one day exposure period. Regarding the oviposition deterrent activity, Ocimum basilicum oil achieved 100% oviposition deterrent (at a dose of 0.5 μl/38.5 ml air) followed by the mixture of Mentha piperita and Ocimum basilicum oils, which achieved 71.22% oviposition deterrent (at a dose of 1.0 μl/38.5 ml air) and Mentha piperita oil, which achieved 39.6% oviposition deterrent (at a dose of 5.0 μl/38.5 ml air). The essential oils and their mixtures studied here determined a significant decrease in the number of eggs hatched and in the emergence of adults. The eggs failed to hatch on using Ocimum basilicum oil at a dose of 0.6 μl/38.5 ml air. However, the number of eggs hatched decreased to 7.4 on using a mixture of oils at a dose of 2.0 μl/38.5 ml air and 14.0 with Mentha piperita oil at a dose of 80.0 μl/38.5 ml air compared with 25.0 eggs hatched in the control experiments. On the other hand, the percentage reduction in emerging adults were 100% for Ocimum basilicum oil, 90.9% for a mixture of the two oils and 72.7% for Mentha piperita oil. Results showed that Ocimum basilicum oil and Ocimum basilicum oils plus Mentha piperita oils in blend are potential alternatives to synthetic fumigants in the treatment of durable agricultural products. Successful adoption of plant oils in the protection of food commodities promises an eco-friendly option compatible with international biosafety regulations.  相似文献   
28.
Abstract

The tested European and Egyptian isolates of Sclerotium cepivorum were able to infect Giza 6 onion cultivar causing white rot disease with a different degrees of disease severity (ranging from sever to weak). The pattern of esterase isozymes produced by the tested isolates of the pathogen showed two main bands (arrows) which were different in density. Such differences in density of bands were present in every run and therefore appear to be indicators for differences among the tested isolates. Analysis of the protein pattern of the tested isolates of the pathogen indicated that the tested isolates had major proteins of a molecular weight of 52, 36, 23 and 16 kDa. Variation between isolates was detected by presence of bands of low molecular weight. Isolate Nos. 1, 4, 5, 7, 8, 9, 10 and 13 had a band at 17 kDa, whereas isolate Nos. 2, 3, 6, 11, 12, 14, and 15 had a band at 20 kDa. Using RAPD analysis to evaluate the genetic diversity of the tested isolates indicated that the tested field population of the pathogen was genetically heterogeneous but shared a number of common bands with molecular weights ranging from 650 to 2500 bp. Based on the DNA banding pattern the tested isolates can be assigned to seven genetically different groups. All tested isolates produced a band at 2500 bp except isolate No. 7. No correlation was exibited between patterns esterase isozmes, protein and DNA patterns of S. cepivorum isolates and their virulence or geographical origin.  相似文献   
29.
Effect of entomopathogenic fungi formulations, Beauveria bassiana, Verticillium lecanii, Metarhizium anisopliae and Paecilomyces fumosoroseus, in controlling Liriomyza trifolii (Burg.) (Diptera: Agromyzidae), compared with botanical insecticide, Nimbecidine against L. trifolii was studied. Investigated compounds were applied twice at 15?days interval between sprays. The percentage reduction in larvae population and crop yield was estimated. Results showed that M. anisopliae was the most efficient compound among the other entomopathogenic fungi. Also, there were no significant differences between Nimbecidine and Bio-Magic (M. anisopliae). However, Nimbecidine and Bio-Magic caused 69.9 and 68.9% reduction in live larvae population after two applications. Also, Nimbecidine and Bio-Magic plots achieved 14.7 and 10.0?kg dry weight seeds/100 plants, respectively, compared to 5.7?kg dry weight seeds/100 plants in control plots. Nimbecidine and Bio-Magic were considered promising compounds in controlling L. trifolii and it could be exploitation in the integrated pest management programme of faba bean crop.  相似文献   
30.

This study investigates the effect of certain entomopathogenic fungi formulations (Beauveria bassiana, Verticillium lecanii, Metarhizium anisopliae and Paecilomyces fumosoroseus) compared with a botanical insecticide, Nimbecidine against Aphis craccivora in broad bean field. Bio-Catch (Verticillium lecanii) was the most effective insecticide to achieve 73.3% reduction followed by Nimbecidine (67.7%), Bio-Magic (61.6%), Priority (50.3%) and the least effective was Bio- Power (Beauveria bassiana) which caused 45.5% reduction in individual aphid populations after two sprayings at 15 days interval between the first and the second sprayings. Bio-Catch and Nimbecidine had promise compounds in controlling Aphis craccivora in faba bean fields.  相似文献   
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