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41.
A thorough investigation into conditions appropriate for effecting combined eco-friendly bioscouring and/or bleaching of cotton-based fabrics was undertaken. Fabrics used include cotton, grey mercerized cotton, cotton/polyester blend 50/50 and cotton/polyester blend 35/65. The four cotton-based fabric were subjected to bioscouring by single use of alkaline pectinase enzymes or by using binary mixtures of alkaline pectinase and cellulase enzymes under a variety of conditions. Results of bioscouring show that, the bioscoured substrates exhibit fabrics performances which are comparable with these of the conventional alkali scouring. It has been also found that, incorporation of ethylenediaminetetraacetic acid (EDTA) in the bioscouring with mixture from alkaline pectinase and cellulase improves the performance of the bioscoured fabrics. Addition of β-cyclodextrin to the bioscouring solution using alkaline pectinase in admixtures with cellulase acts in favor of technical properties and performance of the bioscoured fabrics. Concurrent bioscouring and bleaching by in situ formed peracetic acid using tetraacetylethylenediamine (TAED) and H2O2 was also investigated. The results reveal unequivocally that the environmentally sound technology brought about by current development is by far the best. The new development involves a single-stage process for full purification/preparation of cotton textiles. The new development at its optimal comprises treatment of the fabric with an aqueous formulation consisting of alkaline pectinase enzyme (2 g/L), TAED (15 g/L), H2O2 (5 g/L), nonionic wetting agent (0.5 g/L) and sodium silicate (2 g/L). The treatment is carried out at 60 °C for 60 min. Beside the advantages of the new development with respect to major technical fabric properties, it is eco-friendly and reproducible. This advocates the new development for mill trials.  相似文献   
42.
Hepatocellular carcinoma (HCC) is a worldwide neoplasm for which early diagnosis is difficult and the prognosis is usually poor. Overexpression of cyclooxygenase 2 (COX-2) has been suggested to be associated with hepatocarcinogenesis. Although several COX-2 inhibitors have been used in hepatoma therapy, the genetic background between COX-2 and HCC remains largely unknown. In this study, the association of genotypic polymorphisms in COX-2 with HCC was investigated. 25 healthy individuals served as control (group I), group II: 50 HCV infection patients without any complications, group III: 50 HCV infected patients complicated with cirrhosis and group IV: 75 HCV infected patients complicated with (45 localized and 30 metastatic) HCC from Zagazig University Hospital in Egypt were genotyped by a PCR–RFLP method. The results showed that, no differences in distribution between the HCC and other groups were found. We found ?1195A allele carriers had a higher risk of HCC with HCV infection. As regard the obtained results of serum AFU, a significant increase was detected in HCC as compared with cirrhosis, hepatitis and healthy control groups (p < 0.001). Concerning the obtained results of serum AFP, when HCC group was compared with cirrhosis, hepatitis and healthy controls, a significant increase was observed (p < 0.001). In conclusion: identification of SNP in COX-2 gene promoter and evaluation of serum AFU and AFP give a red light in early detection of HCC which may be reduce its fatal incidence.  相似文献   
43.
Breast cancers (BCs) of the luminal B subtype are estrogen receptor-positive (ER+), highly proliferative, resistant to standard therapies and have a poor prognosis. To better understand this subtype we compared DNA copy number aberrations (CNAs), DNA promoter methylation, gene expression profiles, and somatic mutations in nine selected genes, in 32 luminal B tumors with those observed in 156 BCs of the other molecular subtypes. Frequent CNAs included 8p11-p12 and 11q13.1-q13.2 amplifications, 7q11.22-q34, 8q21.12-q24.23, 12p12.3-p13.1, 12q13.11-q24.11, 14q21.1-q23.1, 17q11.1-q25.1, 20q11.23-q13.33 gains and 6q14.1-q24.2, 9p21.3-p24,3, 9q21.2, 18p11.31-p11.32 losses. A total of 237 and 101 luminal B-specific candidate oncogenes and tumor suppressor genes (TSGs) presented a deregulated expression in relation with their CNAs, including 11 genes previously reported associated with endocrine resistance. Interestingly, 88% of the potential TSGs are located within chromosome arm 6q, and seven candidate oncogenes are potential therapeutic targets. A total of 100 candidate oncogenes were validated in a public series of 5,765 BCs and the overexpression of 67 of these was associated with poor survival in luminal tumors. Twenty-four genes presented a deregulated expression in relation with a high DNA methylation level. FOXO3, PIK3CA and TP53 were the most frequent mutated genes among the nine tested. In a meta-analysis of next-generation sequencing data in 875 BCs, KCNB2 mutations were associated with luminal B cases while candidate TSGs MDN1 (6q15) and UTRN (6q24), were mutated in this subtype. In conclusion, we have reported luminal B candidate genes that may play a role in the development and/or hormone resistance of this aggressive subtype.  相似文献   
44.
Punica granatum L. is one of the famous and old species belonging to Family Punicaceae. The lipoidal and natural pigment extracts of the pomegranate were screened for their antimicrobial activity against nine different microbial pathogens. Three different doses of each extract (50, 100 and 150?μl) at three different contact times (15, 30 and 60?min) were examined. Results can be cleared that, all tested microbial pathogens were inhibited by 150?μl of both extracts at 60?min. Furthermore, the removal efficiency of n-hexane extract was powerful than the pigment extract. Also, the quantitative evaluation of the pigments in the leaves was performed using spectroscopical and HPLC analyses, carotenoids and chlorophylls content of P. granatum L. leaves were spectroscopically determined (mg/g) as 6.7?±?0.214 and 4.9?±?0.251, respectively. Chlorophyll a and b were 2.33?±?0.014 and 1.51?±?0.023, respectively. HPLC analysis of lutein and β-carotene were investigated as 3.652 and 1.915?mg/g. GC/MS analysis of the saponifiable and unsaponifiable fraction of n-hexane extract was carried out and α-amyrin acetate, ergosterol, and α-tocopherol were isolated, purified and identified using different spectroscopical methods. Toxicity assessment demonstrated their high biocompatibility since no toxic effect was recorded.  相似文献   
45.
46.
We report the synthesis and characterisation of a novel series of triazole benzenesulfonamide derivatives, which incorporate the general pharmacophore associated with carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The synthesised compounds were tested in vitro against four human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes, hCA I, hCA II, hCA IV and hCA IX. The obtained results showed that the tumour-associated hCA IX was the most sensitive to inhibition with the synthesised derivatives, with the triazolo-pyridine benzenesulfonamides 14, 16 and 17 being the most effective inhibitors. Some selected compounds were chosen for a single dose anti-proliferative activity testing against a panel of 57 human tumour cell lines and show some anti-proliferative activity ex vivo.  相似文献   
47.
Twenty streptomycete strains were isolated from marine sediment samples collected from Nabq area, Sharm El-Sheikh, Red Sea Coast, Egypt. Four of them produce exopolysaccharides (EPS) showing marked in vitro antitumor activities. Morphological and cultural characteristics of the most significant strain (No. 3) were shown. Moreover, the sequence of this strain showed similarity with Streptomyces carpaticus. The results reveal that EPS produced by Streptomyces carpaticus No. 3 had high cytotoxicity reaching 51.7% and 59.1% against human tumor cells of breast and colon lines respectively. A chemical analysis of EPS indicated that the composing monosaccharides were galactouronic acid, glucose, xylose, galactose, mannose, and fructose with relative ratio of 3:1:1:2:2:1 respectively, with an average molecular weight (Mw) 1.180 × 105?g/mol and of a number average molecular weight (Mn) 1.052 × 105?g/mol. Also the EPS contained uronic acid (0.5072%) and monosaccharide sulphates (21.753%).  相似文献   
48.
Autoimmune hepatitis (AIH) is a chronic hepatitis of unknown etiology and several proinflammatory cytokines are implicated in its pathogenesis. The association of TNF-α gene polymorphism with AIH onset is not fully elucidated especially in the Tunisian population. The aim of this study was to determine the association of TNF-α (-308 G?>?A) polymorphism with AIH susceptibility and with TNF-α expression or clinical manifestations of AIH. A total of 50 AIH patients and 150 controls were included. Evaluation of TNF-α polymorphism was performed by ARMS PCR method. A significantly higher frequence of the AA genotype was found in AIH patients compared to controls (34 vs. 8%, p?=?0.00002, OR 5.88). The frequency of the A-allele was significantly higher in patients with AIH compared to controls (55 vs. 37.3%, p?=?0.002, OR 2.05). The G-allele was significantly more frequent in healthy controls compared to AIH patients [43 vs. 61.3%, p?=?0.001, OR 0.47 (0.3–0.75)]. There was a positive correlation between the A/A genotype and a higher serum expression of TNF-α. The TNF*A allele confer susceptibility to AIH in the Tunisian patients and is associated with increased production of TNF-α. Anti-TNF antibodies could be an alternative to the use of corticotherapy and may avoid the exacerbated immune response in AIH.  相似文献   
49.

Purpose

The aim of this study is to develop and test the applicability of a new subcategory assessment method (SAM) for social life cycle assessment using a case study on high-density polyethylene (HDPE) production by Dow Chemical Canada facility in Alberta, Canada.

Methods

The methodology is characterized by six steps: (1) definition of the goal and scope of the assessment; (2) life cycle inventory data collection including context data at country level and company-specific data for foreground processes; (3) impact assessment where the subcategories’ results for foreground processes at company level are evaluated using a new SAM developed and the country social performance in the different subcategories is evaluated using some assessment intervals; (4) comparing the social performance of foreground processes to the social background context in sector or country; (5) evaluating the social performance of background processes using sector performance evaluation from Product Social Impact Life Cycle Assessment (PSILCA) database or country performance evaluation conducted in the study; (6) and discussion and conclusion.

Results and discussion

The method developed was able to identify the subcategories that need high level or some level of improvements along the cradle-to-gate life cycle of HDPE. In addition, the stakeholders with high negative effect were highlighted in every life cycle stage. Through this approach, Dow Chemical Canada is able to prioritize its actions and focus on the areas where its performance is still low compared to its peers in the sector or compared to the situation in the country. Moreover, through using PSILCA database or country performance evaluation to investigate the social performance of background processes, Dow Chemical Canada can determine the social hotspots areas that need more focus from its suppliers.

Conclusions

Applying the new subcategory assessment approach proposed in this study provides an objective way to assess the subcategories while differentiating between two levels of assessment: (1) the commitment to the social subcategory in the company’s policy (defined as cutoff requirement) and (2) the evidence of good/bad practices of the subcategory. In addition, the comparison of performance of the companies in foreground processes to the social background in sector or country has improved the objectivity further.
  相似文献   
50.
In this study, novel series of thioureido-benzenesulfonamide derivatives bearing an enaminone linker either meta or para oriented and having terminal linear or substituted aromatic or heteroaromatic ring system 516a,b were designed and synthesized based on the general pharmacophoric features of type II VEGFR2 inhibitors. Evaluation of the synthesized compounds against HEPG2 hepatocellular carcinoma cells in vitro identified compounds 5b, 6b and 1013b as most active anticancer agents with IC50 equal to 0.12, 0.29, 0.58, 0.44, 0.42 and 0.66?µM, respectively. These compounds were evaluated for their ability to in vitro inhibit VEGFR2 kinase enzyme. The results demonstrated highly potent dose-related VEGFR2 inhibition with IC50 values in nanomolar range (33, 57, 210, 37, 37 and 220?nM, respectively). The radiosensitizing ability of the most promising compounds was studied which showed an increase in the cell killing effect of radiation after combination with the synthesized compounds which revealed lowered IC50 by nearly 50%. Molecular docking for the most potent compounds was performed to predict their possible binding mode within VEGFR2 active site and they showed binding affinity in a similar way to sorafenib.  相似文献   
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