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Cellulose, the most abundant natural polymer on earth, has recently gained attention for a large spectrum of applications. At a nanoscale, nanocelluloses (mainly involving cellulose nanocrystals or cellulose nanofibrils) possess many predominant features, such as highly thermal and mechanical stability, renewability, biodegradability and non-toxicity. More importantly, the surface modification of such nanocelluloses can be efficiently obtained based on the native surface hydroxyl groups, acting as metal ions chelators. Taking into account this fact, in the present work, the sequential process involving chemical hydrolysis of cellulose and autocatalytic esterification using thioglycolic acid was performed to obtain thiol-functionalized cellulose nanocrystals. The change in chemical compositions was attributed to thiol-functionalized groups and explored via the degree of substitution using a back titration method, X-ray powder diffraction, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Cellulose nanocrystals were spherical in shape and ca. 50 nm in diameter as observed via transmission electron microscopy. The adsorption behavior of such a nanomaterial toward divalent copper ions from an aqueous solution was also assessed via isotherm and kinetic studies, elucidating a chemisorption mechanism (ion exchange, metal chelation and electrostatic force) and processing its operational parameters. In contrast to an inactive configure of unmodified cellulose, the maximum adsorption capacity of thiol-functionalized cellulose nanocrystals toward divalent copper ions from an aqueous solution was 4.244 mg g-1 at a pH of 5 and at room temperature.

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BACKGROUND: Early initiation of treatment is essential for treatment of avian influenza A/H5N1 viral infection in humans, as the disease can lead to rapid development of severe pneumonia which can result in death. Contact with infected poultry is known to be a significant risk factor for contraction of H5N1 infection. However, handling and encountering poultry are a part of most peoples' daily lives, especially in rural communities in Vietnam where epidemic outbreaks among poultry have been continuously reported. Enhancing proper knowledge relating to H5N1 and to the importance of early initiation of treatment are crucial. The aim of this study was to develop an effective educational program to enhance awareness of H5N1 and motivate people to access to health care earlier when H5N1 infection is suspected or likely. METHODOLOGY AND PRINCIPAL FINDINGS: A study was conducted in two agricultural communities (intervention and control groups) in the Ninh Binh province in Vietnam, where epidemic outbreaks of avian influenza have recently occurred in birds. A unique educational intervention was developed and provided to the intervention group, and no intervention was provided to the control group. A knowledge, attitude and practice (KAP) survey was conducted in both groups with a face-to-face interview by trained local healthcare workers at time points before and after the educational intervention. KAP scores were compared between the different time points and between the groups. How educational intervention influenced awareness relating to H5N1 and accessibility of healthcare in the population was analyzed. The study indicated an increased awareness of H5N1 and increased reliance on local health care workers. CONCLUSIONS: The novel educational program which was developed for this study impacted awareness of H5N1, and resulted in more people seeking early access to healthcare, and also resulted in earlier medical intervention for patients with H5N1 avian influenza infection in Vietnam.

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An uncontrolled clinical trial was conducted to investigate the effect of Naltrexone and Cognitive Behavioral Therapy (CBT) on relapse prevention in Green Center, Hochiminh city from October 2002 to August 2003. The sample included 106 addicts (94.3% males) who just passed the acute detoxification process. Patients came to the Green Center 3 times per week (every other day), took 100 mg Naltrexone (150mg on weekend) at the Center, and then got a CBT session in one hour. The Naltrexone-CBT program was prolonged in 6 months. The results: 65/106 (61.3%) patients have terminated the treatment course, in which, only 4 patients (6.2%) followed the whole program (6 months); 7 patients (10.8%) have followed 3 - 6 months. The average of treatment duration was 56.7  51.8 days. There were 29.2% addicts have relapsed, in which the relapse rate of addicts, who have followed the whole program in 6 months was 0%; of addicts who had the treatment duration from 3 – 6 months was 5.3%; and of addicts with the treatment duration less than 2 months was 89.4%. The main recognized reasons for the great drop-out rate were the familial interference which a tendency of shortening the treatment course just after 3 months abstinence of their offspring (27.7%), the high cost of the treatment in comparison to the average income of most people (18.5%), the treatment center is too far from addicts home (16.9%)

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