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61.
62.
Nurlisa Yusuf Ammar Zakaria Mohammad Iqbal Omar Ali Yeon Md Shakaff Maz Jamilah Masnan Latifah Munirah Kamarudin Norasmadi Abdul Rahim Nur Zawatil Isqi Zakaria Azian Azamimi Abdullah Amizah Othman Mohd Sadek Yasin 《BMC bioinformatics》2015,16(1)
Background
Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.Results
This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.Conclusions
The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques. 相似文献63.
64.
Sirisansaneeyakul S Singhasuwan S Choorit W Phoopat N Garcia JL Chisti Y 《Marine biotechnology (New York, N.Y.)》2011,13(5):928-941
The microalgae Chlorella protothecoides UTEX 25, Chlorella sp. TISTR 8991, and Chlorella sp. TISTR 8990 were compared for use in the production of biomass and lipids under photoautotrophic conditions. Chlorella sp. TISTR 8990 was shown to be potentially suitable for lipid production at 30°C in a culture medium that contained only
inorganic salts. For Chlorella sp. TISTR 8990 in optimal conditions in a stirred tank photobioreactor, the lipid productivity was 2.3 mg L−1 h−1 and after 14 days the biomass contained more than 30% lipids by dry weight. To attain this, the nitrogen was provided as
KNO3 at an initial concentration of 2.05 g L−1 and chelated ferric iron was added at a concentration of 1.2 × 10−5 mol L−1 on the ninth day. Under the same conditions in culture tubes (36 mm outer diameter), the biomass productivity was 2.8-fold
greater than in the photobioreactor (0.125 m in diameter), but the lipid productivity was only 1.2-fold higher. Thus, the
average low-light level in the photobioreactor actually increased the biomass specific lipid production compared to the culture
tubes. A light-limited growth model closely agreed with the experimental profiles of biomass production, nitrogen consumption,
and lipid production in the photobioreactor. 相似文献
65.
66.
Yusuf E Bijsterbosch J Slagboom PE Kroon HM Rosendaal FR Huizinga TW Kloppenburg M 《PloS one》2011,6(10):e25426
Objective
To investigate the factors associated with clinical progression and good prognosis in patients with lower limb osteoarthritis (OA).Methods
Cohort study of 145 patients with OA in either knee, hip or both. Progression was defined as 1) new joint prosthesis or 2) increase in WOMAC pain or function score during 6-years follow-up above pre-defined thresholds. Patients without progression with decrease in WOMAC pain or function score lower than pre-defined thresholds were categorized as good prognosis. Relative risks (RRs) for progression and good prognosis with 95% confidence interval (95% CI) were calculated by comparing the highest tertile or category to the lowest tertile, for baseline determinants (age, sex, BMI, WOMAC pain and function scores, pain on physical examination, total range of motion (tROM), osteophytes and joint space narrowing (JSN) scores), and for worsening in WOMAC pain and function score in 1-year. Adjustments were performed for age, sex, and BMI.Results
Follow-up was completed by 117 patients (81%, median age 60 years, 84% female); 62 (53%) and 31 patients (26%) showed progression and good prognosis, respectively. These following determinants were associated with progression: pain on physical examination (RR 1.2 (1.0 to 1.5)); tROM (1.4 (1.1 to 1.6); worsening in WOMAC pain (1.9 (1.2 to 2.3)); worsening in WOMAC function (2.4 (1.7 to 2.6)); osteophytes 1.5 (1.0 to 1.8); and JSN scores (2.3 (1.5 to 2.7)). Worsening in WOMAC pain (0.1 (0.1 to 0.8)) and function score (0.1 (0.1 to 0.7)), were negatively associated with good prognosis.Conclusion
Worsening of self-reported pain and function in one year, limited tROM and higher osteophytes and JSN scores were associated with clinical progression. Worsening in WOMAC pain and function score in 1- year were associated with lower risk to have good prognosis. These findings help to inform patients with regard to their OA prognosis. 相似文献67.
M.S. Ali M. Rahmatullah Rownak Jahan H.K.M. Yusuf A.A. Chowdhury 《Enzyme and microbial technology》1979,1(2):127-128
The effect of the insecticide 2,2-dichlorovinyldimethylphosphate (DDVP) on citric acid fermentation in Aspergillus niger was studied. The appearance of citric acid in the culture medium was increasingly delayed with increasing concentration of the insecticide, and at concentrations at or above 80 μg/ml medium, citric acid production was first observed after 192 h incubation, compared with 96 h in the control flasks. The timing of the maximum rate of citric acid formation was also similarly delayed. DDVP also resulted in a delay in the utilization of inorganic phosphate by the cultures. 相似文献
68.
Sheehan syndrome (SS) or post-partum pituitary necrosis is a pituitary insufficiency secondary to excessive post-partum blood losses. SS is a very significant cause of maternal morbidity and mortality in developing countries although it is a rarity in developed countries in which obstetrical care has been improved. In this study, we reviewed 20 cases retrospectively who were diagnosed as SS in our clinic. The patients aged 40 to 65 years with a mean age of 51.12 +/- 9.44 years (mean +/- SD). Time to make a definitive diagnosis of the disease ranged between 5 and 25 years with a mean of 16.35 +/- 4.74 years. Three of our patient (15%) had a previous diagnosis of SS. Three patients (15%) were referred to emergency service for hypoglycemia, three patients (15%) for hypothyroidism and one patient (5%) for hyponatremia. Dynamic examination of the pituitary revealed GH, Prolactin, FSH, TSH and ACTH insufficiency in all of the patients. One of our patients had a sufficient LH response to LHRH challenge. All of the patients were imaged with pituitary MRI. Eleven patients had empty sella and 9 patients had partial empty sella. SS is still a common problem in our country, especially in rural areas. Considering the duration of disease, important delays occur in diagnosis and treatment of the disease. 相似文献
69.
This review outlines the current and emerging applications of biotechnology, particularly in the production and processing of chemicals, for sustainable development. Biotechnology is “the application of scientific and engineering principles to the processing of materials by biological agents”. Some of the defining technologies of modern biotechnology include genetic engineering; culture of recombinant microorganisms, cells of animals and plants; metabolic engineering; hybridoma technology; bioelectronics; nanobiotechnology; protein engineering; transgenic animals and plants; tissue and organ engineering; immunological assays; genomics and proteomics; bioseparations and bioreactor technologies. Environmental and economic benefits that biotechnology can offer in manufacturing, monitoring and waste management are highlighted. These benefits include the following: greatly reduced dependence on nonrenewable fuels and other resources; reduced potential for pollution of industrial processes and products; ability to safely destroy accumulated pollutants for remediation of the environment; improved economics of production; and sustainable production of existing and novel products. 相似文献
70.
Arslan A Kiralp S Toppare L Yagci Y 《International journal of biological macromolecules》2005,35(3-4):163-167
Immobilization of tyrosinase in conducting copolymer matrices of pyrrole functionalized polydimethylsiloxane/polypyrrole (PDMS/PPy) was achieved by electrochemical polymerization. The polysiloxane/polypyrrole/tyrosinase electrode was constructed by the entrapment of enzyme in conducting matrices during electrochemical copolymerization. Maximum reaction rate (V(max)) and Michaelis-Menten constant (K(m)) were investigated for immobilized enzyme. Enzyme electrodes were prepared in two different electrolyte/solvent systems. The effect of supporting electrolytes, p-toluene sulfonic acid and sodium dodecyl sulfate on the enzyme activity and film morphology were determined. Temperature and pH optimization, operational stability and shelf-life of enzyme electrodes were also examined. Phenolic contents of green and black tea were determined by using enzyme electrodes. 相似文献