Diagnosis of tuberculosis in a high burden resource limited setting

It is estimated that over nine million new tuberculosis (TB) cases worldwide occurred in 2009. However, only 63% of these cases were notified, which is lower than the 75% target set by the DOTS strategy. The lack of ideal diagnostic tests is one of the major barriers to effective TB reduction. The aim of this thesis is to evaluate the efficiency of a novel liquid culture based technique (Microscopic Observation Drug Susceptibility Assay-MODS) and a new generation fluorescence microscope (Light Emitting Diodes fluorescence microscope - LED fluorescence microscope) in diagnosis of TB and multi drug resistant tuberculosis (MDR- TB) in Viet Nam, a resource limited, high burden setting. In the studies described in this thesis, MODS had a higher sensitivity than homogenous smear microscopy, detecting an additional 13% of cases, in diagnosis of TB. Importantly, the pooled sensitivity of MODS (53.0%) was comparable to that of Mycobacteria Growth Indicator Tube technique (MGIT) (57.8%) with clinical presentation as the gold standard. In terms of multi drug resistant tuberculosis (MDR- TB) diagnosis, MODS had rather low sensitivity in detection of Isoniazid (INH) or Rifampicin (RIF) resistant and MDR isolates, 72.6%, 72.7% and 77.8%, respectively against the proportional drug susceptibility testing (DST) method. The low sensitivity of DST-MODS in this study was probably due to low bacterial load samples and use of a high INH critical concentration (O.4~g/ml). For LED microscopy, the detection rate, sensitivity, specificity and false negative of LED 40X were comparable to those of conventional fluorescence microscope and light microscope. The false positive rate • of LED 40X increased in comparison with Ziehl-Neelsen (ZN) reading in the early phases of the evaluation (2.6% and 2.7% vs 0% in the validation and implementation phases vs continuation phase, respectively), probably due to lack of experience among technicians, but no significant difference was found (P>0.05). In the last phase, no false positive result was recorded. Although the reading time of fluorescence-LED (FM-LED) and ZN reading were less than 2 minutes, ZN-light microscope (ZN-LM) reading time was shorter than that of FM-LED40X, especially in positive smears (P=0.007) in the early study phase. By the end of the study, FM-LED reading time was shorter than ZN-LM which was recorded in the early phase. With high experienced technicians there may be little or no additional benefit to case detection if a light microscope is replaced by a fluorescence microscope. In general, MODS and LED microscopy are reliable methods for use in diagnosis of TB in resource limited settings due to their accuracy, reliability and low costs. Large scale operational projects should be conducted to evaluate the feasibility and cost-effectiveness of these methods in countries where these techniques are to be implemented

FINANCIAL SUSTAINABILITY OF MICROFINANCE INSTITUTIONS IN VIET NAM

Microfinance plays an important role in the nation's financial inclusive system. Therefore, the development of Microfinance Institutions (MFIs) increasingly receives the attention of governments, especially in developing countries. In which, financial sustainability is one of the determinants which measures the development of microfinance institutions (MFIs). In this research, the institutionalist approach is applied with the purpose of developing empirical evidence for the determinants that affect the financial sustainability of MFIs in Viet Nam. Financial sustainability is analyzed through the evaluation criteria of the investors and the wholesale lending organizations. The Fixed Effect Model is applied to determine the factors that affect the financial sustainability of MFIs in Viet Nam. Quantitative results show that the financial sustainability of MFIs is governed by five factors, including (i) the growth rate of MFIs’ outstanding loans, (ii) the efficiency of MFIs’ performance, (iii) the ratio of borrowers to the number of staffs of MFIs with a positive impact; (iv) the debt-to-equity ratio of MFIs; and (v) the incremental cost per client of the MFIs with negative effec

Optimization of protein extraction from "Cam" rice bran by response surface methodology

"Cam" rice bran was considered a waste product from rice, which is rich in natural compounds and protein owing to its outstanding nutritional value. This study aimed to establish an optimization model for extracting protein from rice bran, with two responses: extraction yield (%) and protein content (%). The variable parameters included were pH (8.5-9.5), stirring time (3.5-4.5 h), and enzyme incubation temperature (85-95°C). The coefficient of determination for both models were above 0.95, indicating a high correlation between the actual and estimated values. The maximum extraction yield and protein content were achieved when the conditions were set at pH of 9.02, stirring time of 4.02 h, and extraction temperature of 90.6°C. Under these optimum conditions, the predicted protein extracted from rice bran was 43.03% (moisture <13.0%), with an extraction yield of 15.9%. The findings of this study suggested that this protocol can enhance the utilization of rice bran and might be employed on a large scale in the food industry to exploit the nutritional source

Isolation an agar degradation Bacillus sp. AT6 and preliminary application for seaweed saccharification

Background: Agar is a common polysaccharide found in nature. However, agar is strongly resisted to the degradation processing, leading to limitation of its application in various areas. Thus, finding an effective solution for agar saccharification significantly improves the economically effects of agar based substrates.Methods: Soil samples were collected from TienPhong Forestry Ltd. Company, ThuyXuan District, ThuaThien Hue province, Vietnam. Potential agar degrading bacteria were screened on a mineral salt agar medium. The isolate was identified based on 16S rRNA nucleotide sequence, morphological, physiological, and biochemical characteristics. Agarase production was evaluated by modification culture conditions including incubation time, shaking speed, and initial inoculum size. Molecular mass of extracellular agarase was determined by native SDS-PAGE. The effect of pH, temperature, metal ions, and organic solvents were conducted for enzyme characterization. Application of enzyme was investigated on seaweed saccharification.Result: An agar degrading bacterial strain was isolated from soils and identified as Bacillus sp. AT6. Maximal agarase accumulation obtained in the culture containing an inoculum size of 10% (v/v), shaking speed of 210 rpm, and 96 hours incubation. The agarase revealed a single band on zymogram analysis with an apparent molecular weight of 180 kDa. The optimal temperature and pH were 40°C and pH 8.0, respectively. All tested metal ions and organic solvents partially decreased enzyme activity. Treatment seaweed by agarase resulted in reducing sugars release present in the reaction, indicating the saccharification of seaweed was succeeded.Conclusion: Bacillus sp. AT6 is a new report of agarolytic bacteria that produces extracellular agarase enzymes. The present results promise strain AT6 is a great candidate for agar saccharification for industrial application

Tannins: Extraction from Plants

The chapter presents mainly on different extraction methods of tannin. Some technical means required for effective extraction are also presented, for example, collection and treatment of plant and drying and storage of plant. Opportunity and challenges in application of extraction methods are also exhibited in the chapter

Comparison of sensory characteristics of green tea in Thai Nguyen and Phu Tho, Vietnam

Green tea is a popular consumption product in Vietnam. Especially, tea which origins from Tan Cuong, Thai Nguyen has been known for long by its better quality than those coming from other regions on the country. The study aims at comparing and finding out if the difference between tea in Thai Nguyen and Phu Tho can be figured by sensory tasting. Two products picked from Tan Cuong, Thai Nguyen province and two others from Phu Ho district, Phu Tho are were evaluated by a panel of twelve judges (eleven women and one man) who was set from a group of thirty eight peoples, had completed a general training and sensory tasting on tea. The experiment on dry tea (eleven descriptors) was carried out separately of the experiment on brewed tea (twenty-one descriptors) and brewed leaf (five descriptors). All attributes are made notes on the sensory unstructured intensity scale. Statistic analyses have shown typical differences by region among all of trees groups of attributes: dry leaf (10/11 attributes), liquor (6/21 attributes) and brewed leaf (5/5 attributes)

CHARACTERIZATION AND MITIGATION OF VIETNAM COASTAL HAZARDS FOR SUSTAINABLE DEVELOPMENT

Joint Research on Environmental Science and Technology for the Eart

Evaluation of Xpert MTB/RIF and MODS assay for the diagnosis of pediatric tuberculosis

BACKGROUND: Tuberculosis (TB) in children is rarely confirmed due to the lack of effective diagnostic tools; only 10 to 15% of pediatric TB is smear positive due to paucibacillary samples and the difficulty of obtaining high-quality specimens from children. We evaluate here the accuracy of Xpert MTB/RIF in comparison with the Micoroscopic observation drug susceptibility (MODS) assay for diagnosis of TB in children using samples stored during a previously reported evaluation of the MODS assay. METHODS: Ninety-six eligible children presenting with suspected TB were recruited consecutively at Pham Ngoc Thach Hospital in Ho Chi Minh City Viet Nam between May to December 2008 and tested by Ziehl-Neelsen smear, MODS and Mycobacterial growth Indicator (MGIT, Becton Dickinson) culture. All samples sent by the treating clinician for testing were included in the analysis. An aliquot of processed sample deposit was stored at −20°C and tested in the present study by Xpert MTB/RIF test. 183 samples from 73 children were available for analysis by Xpert. Accuracy measures of MODS and Xpert were summarized. RESULTS: The sensitivity (%) in detecting children with a clinical diagnosis of TB for smear, MODS and Xpert were 37.9 [95% CI 25.5; 51.6], 51.7 [38.2; 65.0] and 50.0 [36.6; 63.4], respectively (per patient analysis). Xpert was significantly more sensitive than smear (P=0.046). Testing of additional samples did not increase case detection for MODS while testing of a second sputum sample by Xpert detected only two additional cases. The positive and negative predictive values (%) of Xpert were 100.0 [88.0; 100.0] and 34.1 [20.5; 49.9], respectively, while those of MODS were 96.8 [83.3; 99.9] and 33.3 [19.6; 49.5]. CONCLUSION: MODS culture and Xpert MTB/RIF test have similar sensitivities for the detection of pediatric TB. Xpert MTB RIF is able to detect tuberculosis and rifampicin resistance within two hours. MODS allows isolation of cultures for further drug susceptibility testing but requires approximately one week to become positive. Testing of multiple samples by xpert detected only two additional cases and the benefits must be considered against costs in each setting. Further research is required to evaluate the optimal integration of Xpert into pediatric testing algorithms

Using cassava waste of the cassava starch processing as food for raising African Nightcrawler (Eudrilus eugeniae) to obtain vermicomposting and earthworm biomass

The raising earthworms by cassava waste is a useful solution to reduce environmental pollution caused by cassava starch processing. In this study, cassava waste (including cassava peel, cassava pieces and soil) was used as a food source for raising African Nightcrawler (Eudrilus eugeniae) with three experiments: E1, earthworms were raised in crushed cassava waste right after being discharged; E2, earthworms raised in crushed cassava waste that had been incubated with organic matter after decomposing microbiological preparation for the previous two weeks; E3, earthworms were raised in crushed cassava waste that had self-decomposed naturally for the previous two weeks. The cassava waste was decomposed naturally for 4 weeks for control. The results showed that the content of organic matter, humic acid and total nitrogen in organic cassava humus, obtaining from experiments, increased compared to the control; the total organic matter content reached from 10.4%-15.7%, higher than the control (8.2%) from 1.27-1.92 times, humic acid content reached 0.6 - 0.8% and total nitrogen reached 0.3%. Experiment 3 had the highest quality of humus (organic matter content 15.7%, total nitrogen 0.3%, humic acid 0.7% and fulvic acid 0.5%). The experiment 3 also had the highest earthworm biomass (3.6kg), increasing 30.5% compared to experiment 1 and 19.4% comparing to experiment 2. Therefore, experiment 3 was proposed for application in treatment of cassava waste at larger scale. The organic humus obtaining from raising earthworms by cassava waste can be used as raw material for vermicompost production. The earthworm biomass can be used as protein-rich food for domestic animals (such as chicken, tortoise, eel, fish, etc) or used as nutritious fertilizer.Nuôi giun bằng phế liệu sắn là giải pháp hữu ích nhằm giảm thiểu ô nhiễm môi trường do chế biến tinh bột sắn gây ra. Trong nghiên cứu này, bã thải sắn (bao gồm vỏ, đầu mẩu sắn và bùn đất) được sử dụng làm nguồn thức ăn giun đất Châu Phi (African Nightcrawler (Eudrilus eugeniae) với các thí nghiệm như sau: Thí nghiệm 1: Giun quế được nuôi trong bã thải sắn nghiền ngay sau khi được loại bỏ; Thí nghiệm 2: giun đất được nuôi trong bã thải sắn nghiền đã được ủ với chế phẩm vi sinh phân hủy chất hữu cơ trong hai tuần trước đó; Thí nghiệm 3: Giun đất được nuôi trong bã thải sắn nghiền được để tự phân hủy tự nhiên trong hai tuần trước đó. Đối chứng là bã thải sắn để phân hủy tự nhiên trong 4 tuần. Bên cạnh đó, bã thải sắn nghiền còn được ủ bằng chế phẩm vi sinh phân hủy chất hữu cơ trong 4 tuần để cung cấp thêm số liệu so sánh giữa các thí nghiệm (Thí nghiệm 4). Các thí nghiệm được theo dõi trong 4 tuần. Kết quả cho thấy: Kết quả cho thấy: hàm lượng chất hữu cơ, axit humic và nitơ tổng trong mùn sắn hữu cơ thu được từ thí nghiệm đều tăng so với đối chứng: hàm lượng chất hữu cơ tổng số đạt từ 10,4% -15,7%, cao hơn đối chứng (8,2%) so với 1,27-1,92 lần, hàm lượng axit humic đạt 0,6 - 0,8% và nitơ tổng số đạt 0,3%. Trong đó, thí nghiệm 3 có chất lượng mùn cao nhất (hàm lượng chất hữu cơ 15,7%, đạm tổng số 0,3%, axit humic 0,7% và axit fulvic 0,5%). Thí nghiệm 3 cũng có sinh khối giun quế cao nhất (3,6kg), tăng 30,5% so với thí nghiệm 1 và 19,4% so với thí nghiệm 2. Do đó, thí nghiệm 3 đã được đề xuất ứng dụng để xử lý phế thải sắn ở quy mô lớn hơn. Chất mùn hữu cơ thu được từ việc nuôi trùn quế bằng phế thải sắn có thể được sử dụng làm nguyên liệu để sản xuất phân trùn quế. Sinh khối trùn quế có thể dùng làm thức ăn giàu đạm cho vật nuôi (như gà, ba ba, lươn, cá ...) hoặc làm phân bón dinh dưỡng