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91.
Salmonellosis, a communicable disease caused by members of the Salmonella species, transmitted to humans through contaminated food or water. It is of paramount importance, to generate accurate detection methods for discriminating the various Salmonella species that cause severe infection in humans, including S. Typhi and S. Paratyphi A. Here, we formulated a strategy of detection and differentiation of salmonellosis by a multiplex polymerase chain reaction assay using S. Typhi non-protein coding RNA (sRNA) genes. With the designed sequences that specifically detect sRNA genes from S. Typhi and S. Paratyphi A, a detection limit of up to 10 pg was achieved. Moreover, in a stool-seeding experiment with S. Typhi and S. Paratyphi A, we have attained a respective detection limit of 15 and 1.5 CFU/mL. The designed strategy using sRNA genes shown here is comparatively sensitive and specific, suitable for clinical diagnosis and disease surveillance, and sRNAs represent an excellent molecular target for infectious disease.  相似文献   
92.
Kojic acid is widely used to inhibit the browning effect of tyrosinase in cosmetic and food industries. In this work, synthesis of kojic monooleate ester (KMO) was carried out using lipase-catalysed esterification of kojic acid and oleic acid in a solvent-free system. Response Surface Methodology (RSM) based on central composite rotatable design (CCRD) was used to optimise the main important reaction variables, such as enzyme amount, reaction temperature, substrate molar ratio, and reaction time along with immobilised lipase from Candida Antarctica (Novozym 435) as a biocatalyst. The RSM data indicated that the reaction temperature was less significant in comparison to other factors for the production of a KMO ester. By using this statistical analysis, a quadratic model was developed in order to correlate the preparation variable to the response (reaction yield). The optimum conditions for the enzymatic synthesis of KMO were as follows: an enzyme amount of 2.0 wt%, reaction temperature of 83.69°C, substrate molar ratio of 1:2.37 (mmole kojic acid:oleic acid) and a reaction time of 300.0 min. Under these conditions, the actual yield percentage obtained was 42.09%, which is comparably well with the maximum predicted value of 44.46%. Under the optimal conditions, Novozym 435 could be reused for 5 cycles for KMO production percentage yield of at least 40%. The results demonstrated that statistical analysis using RSM can be used efficiently to optimise the production of a KMO ester. Moreover, the optimum conditions obtained can be applied to scale-up the process and minimise the cost.  相似文献   
93.
This work aimed to develop a chiral separation method of ketoconazole enantiomers using electrokinetic chromatography. The separation was achieved using heptakis (2, 3, 6‐tri‐O‐methyl)‐β‐cyclodextrin (TMβCD), a commonly used chiral selector (CS), as it is relatively inexpensive and has a low UV absorbance in addition to an anionic surfactant, sodium dodecyl sulfate (SDS). The influence of TMβCD concentration, phosphate buffer concentration, SDS concentration, buffer pH, and applied voltage were investigated. The optimum conditions for chiral separation of ketoconazole was achieved using 10 mM phosphate buffer at pH 2.5 containing 20 mM TMβCD, 5 mM SDS, and 1.0% (v/v) methanol with an applied voltage of 25 kV at 25 °C with a 5‐s injection time (hydrodynamic injection). The four ketoconazole stereoisomers were successfully resolved for the first time within 17 min (total analysis time was 28 min including capillary conditioning). The migration time precision of this method was examined to give repeatability and reproducibility with RSDs ≤5.80% (n =3) and RSDs ≤8.88% (n =9), respectively. Chirality 27:223–227, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
94.
This work presents an experimental analysis on the tunable localized surface plasmon resonance (LSPR), obtained from deposited silver (Ag) thin films of various thicknesses. Silver thin films are prepared using electron beam deposition and undergo an annealing process at different temperatures to produce distinctive sizes of Ag metal nanoparticles (MNPs). The variability of structure sizes and shapes provides an effective means of tuning the position of the LSPR within a wide wavelength range. This paper provides an estimation of LSPR over a broad wavelength range by a process in which the resonance spectra of silver nanoparticles differing in thickness are simulated using an adaptive neuro-fuzzy inference system (ANFIS) method. The ANFIS methodology allows for estimation of sizes of granular structures formed on top of a wafer at certain temperatures, whereupon these intelligent estimators are implemented using MATLAB and their subsequent performances are investigated. The results presented in this paper show the effectiveness of the method of simulation.  相似文献   
95.
A new species of Alternaria causing leaf spot of pepper (Capsicum annuum) obtained from the Cameron highlands, Pahang, Malaysia, was determined based on phylogenetic analyses, morphological characteristics, and pathogenicity assays. Phylogenetic analyses of combined dataset of the glyceraldehyde-3-phosphate dehydrogenase (gpd), Alternaria allergen a 1 (Alt a1) and calmodulin genes revealed that the new isolates clustered into a subclade distinct from the closely related Alternaria species A. tomato and A. burnsii. The solitary or short chains of conidia resemble those of A. burnsii. However, conidia with long beaks are morphologically similar to A. tomato. Hence, the pathogenic fungus is proposed as Alternaria capsicicola sp. nov. Pathogenicity assays indicated that A. capsicicola causes leaf spot on pepper.  相似文献   
96.
Background:Hearing loss due to noise can cause the disturbances toward the quality of life and cause mechanical damage and metabolic decompensation. Distortion Product Otoacoustic Emission (DPOAE) is an examination to assess the sensory function of outer hair cells. Superoxide Dismutase (SOD) and Malondialdehyde (MDA) are markers of oxidative stress. The aim of this study was to identify the correlation between DPOAE examination and SOD and MDA expression in rats exposed to noise.Methods:This research was conducted on 27 rats which were divided into 3 groups, group 1 (control), group 2, and group 3 were groups with 100 dB and 110 dB noise exposure respectively.Results:Our findings show a decrease in SOD expression and DPOAE values as well as an increase in MDA expression in rats exposed to noise and there is a positive correlation between Signal to Noise Ratio (SNR) value with SOD expression (r= 0.733, p= 0.025) and a negative correlation between SNR value with MDA expression (r= -0.678, p= 0.045).Conclusion:our study find the correlation of oxidant and antioxidant status values in the organ of corti and changes in the function of outer hair cells in noise-exposed rat models.Key Words: Malondialdehyde, Noise Induced Hearing Loss, Otoacoustic Emission, Superoxide Dismutase  相似文献   
97.
A study was carried out to optimize selected parameters for decolorization of a triarylmethane dye, such as crystal violet by white rot fungus, Pycnoporus sanguineus, pellets. The parameters studied were initial dye concentration (ppm), agitation speed (rpm), and process time (days) and were optimized using response surface methodology (RSM). It is shown that process time, agitation speed, and their interactions have significant effects on the decolorization process. Following the optimization, the decolorization study was extended to a stirred tank reactor (STR) process. Effects of different geometry of impellers on the decolorization process and power consumption were studied. Novel impeller geometries, such as 180° curved blade and 60° angled blade impellers, were used in the STR. The application of 180° curved blade impeller resulted in higher percentage of decolorization at a relatively less power consumption as compared with 60° angled blade impeller.  相似文献   
98.
Retinol-binding protein (RBP), retinol, and modified-relative-dose response (MRDR) are used to assess vitamin A status. We describe vitamin A status in Ugandan children and women using dried blood spot (DBS) RBP, serum RBP, plasma retinol, and MRDR and compare DBS-RBP, serum RBP, and plasma retinol. Blood was collected from 39 children aged 12–23 months and 28 non-pregnant mothers aged 15–49 years as a subsample from a survey in Amuria district, Uganda, in 2016. DBS RBP was assessed using a commercial enzyme immunoassay kit, serum RBP using an in-house sandwich enzyme-linked immunosorbent assay, and plasma retinol/MRDR test using high-performance liquid chromatography. We examined (a) median concentration or value (Q1, Q3); (b) R2 between DBS-RBP, serum RBP, and plasma retinol; and (c) Bland-Altman plots. Median (Q1, Q3) for children and mothers, respectively, were as follows: DBS-RBP 1.15 µmol/L (0.97, 1.42) and 1.73 (1.52, 1.96), serum RBP 0.95 µmol/L (0.78, 1.18) and 1.47 µmol/L (1.30, 1.79), plasma retinol 0.82 µmol/L (0.67, 0.99) and 1.33 µmol/L (1.22, 1.58), and MRDR 0.025 (0.014, 0.042) and 0.014 (0.009, 0.019). DBS RBP-serum RBP R2 was 0.09 for both children and mothers. The mean biases were −0.19 µmol/L (95% limits of agreement [LOA] 0.62, −0.99) for children and −0.01 µmol/L (95% LOA −1.11, −1.31) for mothers. DBS RBP-plasma retinol R2 was 0.11 for children and 0.13 for mothers. Mean biases were 0.33 µmol/L (95% LOA −0.37, 1.03) for children, and 0.29 µmol/L (95% LOA −0.69, 1.27) for mothers. Serum RBP-plasma retinol R2 was 0.75 for children and 0.55 for mothers, with mean biases of 0.13 µmol/L (95% LOA −0.23, 0.49) for children and 0.18 µmol/L (95% LOA −0.61, 0.96) for mothers. Results varied by indicator and matrix. The serum RBP-retinol R2 for children was moderate (0.75), but poor for other comparisons. Understanding the relationships among vitamin A indicators across contexts and population groups is needed.  相似文献   
99.
BackgroundIn Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance.Method and resultsThe insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species.ConclusionThe present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program.  相似文献   
100.
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