Sacharose density gradient separation of Ehrlich ascites carcinoma and L-5178Y tumor cells in different cell cycle phases

Optimal conditions were determined for the distribution of Ehrlich ascites carcinoma (EAC) and L-5178Y mouse tumor cells, proliferating in vivo, by their age within the cell cycle by sedimentation in a buffered linear sacharose density gradient. Measurements of cell size, DNA content and incorporation of tritiated thymidine in successive parts of the gradient confirmed the actual separation of cells of different age: in the upper fractions there were cells in G1 phase, in the middle fractions in S phase and in the lower layers of the gradient there were cells in G2 and/or M phase.     

Responses of fabric from lyocell/natural bamboo yarn to loading

With the growing demand for more comfortable, healthier and environmentally friendly products, research and development has been increasingly focusing on new environmentally friendly materials and products. One of the environmentally friendly materials is the bamboo fibre with its numerous favourable performing properties. The use of bamboo fibres increases every year, which was the main reason for choosing yarn from the mixture of lyocell fibres and natural bamboo fibres with the ratio 80/20 for the research. With the research, the tensile behaviour of woven fabrics with cotton yarn in warp and lyocell/natural bamboo yarn in the weft direction in comparison with cotton woven fabrics was studied. Twelve fabrics which differed in their construction properties were designed and produced. Two different weaves were chosen, i.e. plain and twill weave, and three different densities in weft. The results of the research show that the presence of lyocell/natural bamboo yarn in the weft direction improves the mechanical properties such as breaking stress, stress in the yield point, elasticity modulus in the weft direction of analysed fabrics, while in the warp direction, the weave type and weave density express a greater influence on the mechanical properties of analysed fabrics.     

Antioxidant stability of small fruits in postharvest storage at room and refrigerator temperatures

Strawberries (Fragaria ananassa), raspberries (Rubus idaeus) and red currants (Ribes rubrum), as well as two drupes, cherries (Prunus avium), and sour cherries (Prunus cerasus), were subjected to two storage temperatures (4 °C and 25 °C) and phytochemicals concentrations (total phenols, flavonoids and anthocyanins) as well as antioxidant capacity (DPPH, ABTS and FRAP assays) were monitored until the fruit visually spoiled. Red currants and strawberries exhibited the highest initial total phenol (TP) contents (322.40 ± 5.56 and 335.47 ± 6.12 mg GAE/100 g FW, respectively) and maintained the highest TP contents throughout storage at both temperatures. Storage of at 25 °C as opposed to 4 °C, facilitated faster spoilage of analyzed fruits. In addition, most fruits stored at 4 °C, exhibited slightly higher antioxidant activity values at the end of storage according to all three antioxidant activity assays as opposed to fruits stored at 25 °C. The dynamic evolution of antioxidant capacity at both temperatures reflected the transient changes in phytochemical composition of small fruits in storage.     

Comparative study of polyphenols and caffeine in different coffee varieties affected by the degree of roasting

The bioactive composition of coffee, as one of the most popular beverages in the world, has attracted interest as a potential source of beneficial bioactive compounds, especially polyphenols and caffeine. Since the content of these compounds is affected by the processing conditions, the objective of this study was to determine the content of polyphenolic compounds and caffeine in four different coffee varieties: Minas and Cioccolatato (Coffea arabica), and Cherry and Vietnam (Coffea canephora syn. Coffea robusta), roasted by three varying degrees (light, medium and dark). The content of the polyphenolic compounds and the antioxidant capacity of coffees were determined using UV/Vis spectrophotometric methods, while the content of chlorogenic acid derivatives was determined using HPLC analysis. The caffeine content was determined by means of two spectrophotometric methods, as well as HPLC analysis. Additionally, raw caffeine was also obtained by an isolation procedure with chloroform. Cherry coffee, a variety of C. canephora exhibited the highest overall content of total phenols (42.37 mg GAE/g), followed by Minas coffee, while Cioccolatato contained the lowest TPC (33.12 mg GAE/g). Cherry coffee also exhibited the highest content of individual classes of polyphenols (flavan-3-ols, procyanidins and tannins), while the highest content of chlorogenic acid (CQA) derivatives was determined in Minas and Cioccolatato coffees (C. arabica). The highest content of total and individual polyphenolic compounds was determined in coffees roasted in both light and medium roasting conditions, which was also observed for the content of CQA derivatives and antioxidant capacity of roasted coffees. The highest caffeine content in the coffee samples was determined by employing the HPLC analysis (0.06–2.55%). Light roasted Cherry coffee contained the highest overall content of caffeine among all coffees, which exhibited a decrease with intensified roasting.     

Analysis and recommendations for building energy efficiency financing in Malaysia

This paper provides an overview of the Malaysian Energy Efficiency regulatory framework as well as current financing and incentive mechanisms available to the building sector. The review has found that some of the existing financing schemes have been successful while others could leverage on other existing schemes to improve its effectiveness. The review will explore the strengths and gaps of the available schemes and will propose some ways to increase the uptake up rate of the schemes. The potential impact of the proposed recommendations will be discussed supported by projected energy and CO₂ reductions.     

Solvent compatible cobalt ion species as additives to polyimides

A series of solvent compatible cobalt compounds have been synthesized as additives to polyimides. The resultant cobalt doped polyimide films are smooth, flexible and shiny. The doped films display lowered electrical resistivities by 3 to 4 orders of magnitude compared to the undoped polyimide. Additive migration to the surface of the film generating a cobalt oxide layer has been observed.     

Differential expression of telomerase activity in human cervical cancer and cervical intraepithelial neoplasia lesions

PURPOSE: Telomeres are tandem arrays of repeated DNA sequences located at the ends of eukaryotic chromosomes, and are synthesized by the enzyme telomerase. Loss of telomeric DNA may play an important role in the development of human cancers. However, very little is known about the status of telomerase during human cervical cancer development. PATIENTS AND METHODS: Telomerase activity was measured by telomere repeat amplification protocol (TRAP) assay in 24 cervical cancers, one carcinoma in situ (CIS), and 20 cervical intraepithelial neoplasia (CIN) lesions. Adjacent nontumor cervical tissue from the same 24 cervical cancer patients and normal cervical tissues from 11 control individuals also were examined for the presence of telomerase activity. RESULTS: Twenty two of the 24 (91.7%) cervical cancer specimens and the single CIS tissue were strongly positive for telomerase activity. Relatively weak but distinctive telomerase activity also was detectable in one of four CIN-I (25%), two of eight CIN-II (25%), and two of eight CIN-III (25%), respectively. However, telomerase activity was not found in the 24 corresponding nontumor cervical tissues from the same cervical cancer patients and the 11 normal cervical tissues from control individuals. CONCLUSION: The majority of cervical cancers contain strong telomerase activity. Significant proportions of noncancerous CIN tissues also contain telomerase activity, although weaker than that in cervical cancer. It seems that there is a progressive increase of telomerase activity in association with an increased degree of cervical malignancy. These results seem to suggest that the expression of telomerase may play a crucial role in cervical cancer carcinogenesis.