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11.
The direct electrocatalytic oxidation of glucose in alkaline medium at nanoscale nickel hydroxide modified carbon ionic liquid electrode (CILE) has been investigated. Enzyme free electro-oxidation of glucose have greatly been enhanced at nanoscale Ni(OH)(2) as a result of electrocatalytic effect of Ni(+2)/Ni(+3) redox couple. The sensitivity to glucose was evaluated as 202 microA mM(-1)cm(-2). From 50 microM to 23 mM of glucose can be selectively measured using platelet-like Ni(OH)(2) nanoscale modified CILE with a detection limit of 6 microM (S/N=3). The nanoscale nickel hydroxide modified electrode is relatively insensitive to electroactive interfering species such as ascorbic acid (AA), and uric acid (UA) which are commonly found in blood samples. Long-term stability, high sensitivity and selectivity as well as good reproducibility and high resistivity towards electrode fouling resulted in an ideal inexpensive amperometric glucose biosensor applicable for complex matrices.  相似文献   
12.
Pollen proteins that are located in the cytoplasm or on the surface of the exine can function as allergens and evoke immune system responses in sensitive patients, leading to allergic rhinitis and asthma. In this research, the pollen allergenicity and ability to induce IgE response of the pollen of two plant species were studied in rats. Acroptilon repens is an herbaceous, invasive plant with entomophilous pollen, while Juglans regia which is a tree crop produces anemophilous pollen. Immunoblot analysis using sera of sensitised rats revealed IgE reactivity to three protein bands including the 70, 41 and 25.12 kDa bands present in the A. repens pollen extract, while only one single immunogenic band of 11 kDa was detected in J. regia pollen extract. Both pollen extracts increased the eosinophil content and caused some clinical signs of allergy in treated rats. The results showed that both entomophilous and anemophilous pollen can be allergenic.  相似文献   
13.
Galactosemia type 2 is an autosomal recessive disorder characterized by the deficiency of galactokinase (GALK) enzyme due to missense mutations in GALK1 gene, which is associated with various manifestations such as hyper galactosemia and formation of cataracts. GALK enzyme catalyzes the adenosine triphosphate (ATP)–dependent phosphorylation of α‐d ‐galactose to galactose‐1‐phosphate. We searched 4 different literature databases (Google Scholar, PubMed, PubMed Central, and Science Direct) and 3 gene‐variant databases (Online Mendelian Inheritance in Man, Human Gene Mutation Database, and UniProt) to collect all the reported missense mutations associated with GALK deficiency. Our search strategy yielded 32 missense mutations. We used several computational tools (pathogenicity and stability, biophysical characterization, and physiochemical analyses) to prioritize the most significant mutations for further analyses. On the basis of the pathogenicity and stability predictions, 3 mutations (P28T, A198V, and L139P) were chosen to be tested further for physicochemical characterization, molecular docking, and simulation analyses. Molecular docking analysis revealed a decrease in interaction between the protein and ATP in all the 3 mutations, and molecular dynamic simulations of 50 ns showed a loss of stability and compactness in the mutant proteins. As the next step, comparative physicochemical changes of the native and the mutant proteins were carried out using essential dynamics. Overall, P28T and A198V were predicted to alter the structure and function of GALK protein when compared to the mutant L139P. This study demonstrates the power of computational analysis in variant classification and interpretation and provides a platform for developing targeted therapeutics.  相似文献   
14.

Background

Exclusive breastfeeding up to the completion of the sixth month of age is the national infant feeding recommendation for Sri Lanka. The objective of the present study was to collect data on exclusive breastfeeding up to six months and to describe the association between exclusive breastfeeding and selected socio-demographic factors.

Methods

A clinic based cross-sectional study was conducted in the Medical Officer of Health area, Beruwala, Sri Lanka in June 2006. Mothers with infants aged 4 to 12 months, attending the 19 child welfare clinics in the area were included in the study. Infants with specific feeding problems (cleft lip and palate and primary lactose intolerance) were excluded. Cluster sampling technique was used and consecutive infants fulfilling the inclusion criteria were enrolled. A total of 219 mothers participated in the study. The statistical tests used were survival analysis (Kaplan-Meier survival curves and Cox proportional Hazard model).

Results

All 219 mothers had initiated breastfeeding. The median duration of exclusive breastfeeding was four months (95% CI 3.75, 4.25). The rates of exclusive breastfeeding at 4 and 6 months were 61.6% (135/219) and 15.5% (24/155) respectively. Bivariate analysis showed that the Muslim ethnicity (p = 0.004), lower levels of parental education (p < 0.001) and being an unemployed mother (p = 0.021) were important associations of early cessation of exclusive breastfeeding. At the time of the study, 62% (135/219) of infants were receiving feeds via a bottle and 23% (51/219) were receiving infant formula. Muslim ethnicity was significantly associated with bottle and formula feeding (p < 0.001). Bottle feeding was also significantly higher among mothers with a low level of education and among employed mothers.

Conclusion

The rate of breastfeeding initiation and exclusive breastfeeding up to the fourth month is very high in Medical Officer of Health area, Beruwala, Sri Lanka. However exclusive breastfeeding up to six months is still low and the prevalence of inappropriate feeding practices is high.  相似文献   
15.
16.
Hepatitis B virus (HBV) transmission via blood and other body fluids from infected individuals to healthy people has been largely demonstrated. However, in the current literature, there is little information available on the potential role of cerumen in HBV transmission. Cerumen and blood were collected from 70 patients infected with HBV and 70 volunteer healthy people were selected as the control group, and the samples were evaluated by ELISA and Real-time PCR. All the patients proved positive for HBsAg and anti HBc total. Sixty-one of the 70 cerumen samples of cases (82.1%) and 5 (7%) of controls were positive for HBV DNA with ranges from 1.53 × 102 to 2.9 × 108 and 1.3 × 102-2.6 × 105/ml, respectively. In three patients, the level of HBV DNA in cerumen was higher than that in the serums. The patients who were positive for HBeAg showed a higher rate of HBVDNA in the serum and cerumen.The results of this study showed the level of HBV DNA as a probably indicator of high risk transmission factor, which was present in the cerumen of chronic hepatitis B patients in west of Iran.  相似文献   
17.
Bioprocess and Biosystems Engineering - Based on cellulose biosynthesis pathway of Gluconacetobacterxylinus BPR2001 and E. coli Nissle 1917, bcsA and bcsB genes have been selected and...  相似文献   
18.
Bee venom (BV) is a biotoxin with biologically active peptides which have cell lysis and hemolytic activity properties. These properties can be affected under different storage conditions or during the production process. In present study, we investigated effects of a number of physicochemical factors, including temperature, pH, UV radiation, ultrasound waves and storage time on hemolytic activity of BV. Maximum absorption and melting temperature of BV solution were obtained as 280 nm and ~70 °C, respectively. Cell hemolysis 50 (CH50) -concentration of BV that can lyse 50% of red blood cells- was determined as 0.94 μg/ml at ambient temperature. CH50 was shown not to be importantly varied at temperature up to 60 °C, pH value 2 to 13 and under UV/ ultrasound radiation. Storage at ?20, 6 and 25 °C for 6 months made about 2.5, 35 and 1000 times increase in CH50. From the results, it may be concluded that BV is a relatively resistant hemolytic agent and can be used in a variety of laboratory research and product manufacturing methods.  相似文献   
19.
Probiotics and Antimicrobial Proteins - This study was conducted to evaluate the effects of synbiotic supplementation on metabolic profiles in diabetic patients undergoing hemodialysis (HD). This...  相似文献   
20.
Mycelial compatibility of 62 isolates of Valsa malicola from different hosts and areas of Iran were investigated on potato dextrose agar (PDA) and oat meal agar (OMA). Four mycelial compatibility groups (MCGs) on PDA, 1–4, including three single membered (1–3) and a 58 membered (4) were identified. However, 8 MCGs, 1–8, consisting of 6 single membered (1–3, 5, 6 and 8), a 6 membered (4) and a 50 membered (7) were identified on OMA. On PDA, the number of groups and the time to achieve results were less than on OMA as well as the barrage zones were clearer on PDA than OMA. There was no correlation between groups and host or geographical origins of the isolates. The low number of identified MCGs on both culture media revealed low genetic diversity of investigated isolates of V. malicola.  相似文献   
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