Investigation of high order stochastic differential equations using averaging method

The averaging method is a useful tool for investigating both deterministic and stochastic quasilinear system. In the stochastic problems, however, the method has often been developed only for mechanical systems subjected to white noise excitations.In the paper this method is applied to high order stochastic differential equations. The nonlinear oscillations in high order deterministic differential equations were investigated in the fundamental work of Prof. Nguyen Van Dao. As an application of high order stochastic differential equations the nonlinear oscillation of single degree of freedom systems subjected to the excitation of a class of colored noises is outlined. The results obtained show that the higher order averaging method can also be successfully extended to the cases of colored noise excitation

Study on synthesis of carboxymethyl cellulose from pineapple leaf waste and its potential applications as a thickener

In this study, cellulose and hemicellulose were successfully extracted from pineapple leaf waste at yields of 58.8 and 16.1% by dried weight, respectively. Carboxymethyl cellulose (CMC) was synthesised from pineapple leaf cellulose by an esterification process using sodium hydroxide (NaOH) and monochloroacetic acid (MCA) with isopropanol as the supporting medium. Preparation of CMC was investigated by varying three free factors, namely, NaOH concentration, MCA dose, and cellulose size. The carboxymethylation process was optimised to produce CMC with differing degrees of substitution (DS). The highest DS of CMC (0.86) was obtained with 15% (w/v) NaOH solution, 0.6 g of MCA/g cellulose, and 50 μm cellulose. The obtained CMC were characterised by FTIR spectroscopy, SEM images and XRD diffractions. Moreover, the thickening performance of obtained CMC was also determined. The influence of the CMC’s molecular weight and degree of substitution on the viscosity of 1% (w/v) aqueous solution was tested. The experimental results suggest that the viscosity of the solution increases with increasing molecular weight and degree of substitution of CMC

The initial study of EBNA-2 polymorphisms in nasopharyngeal carcinoma in Vietnam

Epstein-Barr virus (EBV) infection is the main cause of Nasopharyngeal Carcinoma (NPC). EBNA-2, one of the most important genes participating in the formation of NPC, also helps EBV evade an attack on the immune system. EBNA-2 has 4 variants including E2-A, E2-B, E2-C and E-2D, of which E2-A and E2-C are the characterized variants for NPC. This study aimed to evaluate the variations of EBNA-2 in NPC biopsy samples of Vietnamese patients. This initial study used 10 biopsy samples, which were positively confirmed to NPC, collected from Cho Ray Hospital. Nested PCR – nucleotide sequencing was applied to analyze the variants of EBNA-2. The results showed that 8 out of 10 samples, accounting for 80%, were positive to EBNA-2. Additionally, only two variants, E-2A and E-2C were detected in our study, in which, E2-A subtype was identified as the predominant subtype. These findings would provide initial data about potential contribution of EBNA-2 polymorphisms to etiology of NPC in Vietnamese population

Initial study of single nucleotide polymorphism genotyping of Epstein-barr nuclear antigen 1 (EBNA-1) from Vietnamese nasopharyngeal biopsy samples

Background: Epstein-Barr virus nuclear antigen (EBNA1), encoded by EBNA-1 gene, has been shown as one of the most frequently detected protein in Nasopharyngeal carcinoma (NPC), which the most common and highly incident cancer of head and neck cancer in Asian countries. The geographically-associated polymorphisms of EBNA-1 have been observed in East-Southern Asia, including Vietnam. The subtype V-val EBNA-1 has been demonstrated that it may contribute to the oncogenesis of NPC. This current study is initially performed to characterize the variations of EBNA-1 in NPC biopsy samples from Vietnamese patients. Methods: Nested PCR-sequencing was applied to amplify and characterize the C-terminal region of EBNA-1 gene by the designed oligonucleotide primers. Results: 10 NPC biopsy samples were enrolled, as the results, only two patterns of EBNA-1 variations: P-ala and V-val were observed. In addition, of these two subtypes, the frequency of V-val and P-ala were determined counting for 80% (8 of 10 cases) and 20% (2 of 10 cases), respectively. It indicated the V-val subtype preferentially exists in biopsy NPC samples, which collected from Vietnamese patients. Conclusion: We successfully designed the nested PCR-sequencing primer for detection of EBNA-1 variations based on the data collected from previous study. In our initial study, the sub-strain of EBV with V-val subtype of EBNA-1 infects NPC preferentially to those from biopsies of NPC patients. In further study, it is necessary for a larger number of samples and non-cancerous samples in order to confirm the characteristic of EBNA-1 variations, as well as determination of the association V-val subtype with NPC in Vietnamese patients

Host Transcription Profile in Nasal Epithelium and Whole Blood of Hospitalized Children Under 2 Years of Age With Respiratory Syncytial Virus Infection.

BACKGROUND: Most insights into the cascade of immune events after acute respiratory syncytial virus (RSV) infection have been obtained from animal experiments or in vitro models. METHODS: In this study, we investigated host gene expression profiles in nasopharyngeal (NP) swabs and whole blood samples during natural RSV and rhinovirus (hRV) infection (acute versus early recovery phase) in 83 hospitalized patients <2 years old with lower respiratory tract infections. RESULTS: Respiratory syncytial virus infection induced strong and persistent innate immune responses including interferon signaling and pathways related to chemokine/cytokine signaling in both compartments. Interferon-α/β, NOTCH1 signaling pathways and potential biomarkers HIST1H4E, IL7R, ISG15 in NP samples, or BCL6, HIST2H2AC, CCNA1 in blood are leading pathways and hub genes that were associated with both RSV load and severity. The observed RSV-induced gene expression patterns did not differ significantly in NP swab and blood specimens. In contrast, hRV infection did not as strongly induce expression of innate immunity pathways, and significant differences were observed between NP swab and blood specimens. CONCLUSIONS: We conclude that RSV induced strong and persistent innate immune responses and that RSV severity may be related to development of T follicular helper cells and antiviral inflammatory sequelae derived from high activation of BCL6

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Removal of Tetracycline from Aqueous Solution Using Nanocomposite Based on Polyanion-Modified Laterite Material

This work investigated the removal of antibiotic tetracycline (TC) from wastewater using nanocomposite material based on laterite modified with polyanion, polystyrene sulfonate (PSS). The effective factors influenced on the TC removal using nanocomposite PSS-modified laterite (NCPML) were optimized and found to be pH 4, solid-liquid ratio 5 mg/mL, and contact time 180 min. The highest removal of TC reached about 88% under the optimum adsorption conditions. The adsorption isotherm and kinetics of TC adsorption onto NCPML were in good agreement with the Langmuir and pseudo-second-order models, respectively. The characteristics of the NCPML material before and after TC adsorption were examined by zeta (ζ) potential measurements, Brunauer–Emmett–Teller (BET) method, and Fourier transform infrared spectroscopy (FT-IR). The TC adsorption onto NCPML was induced by electrostatic interaction, hydrogen bonding, and diffusion interaction. The TC removal from wastewater was approximately 94% while efficiency still reached 66% after five regenerations. Our research reveals that NCPML is a high-performance adsorbent for TC removal from wastewater

Determination of drug-related problems among type 2 diabetes outpatients in a hospital in Vietnam: A cross-sectional study.

IntroductionDrug-related problems (DRPs) are common in clinical practice and occur at all stages of the medication process. The major factor contributing to DRPs is prescription, although patients' poor adherence to treatment is also a significant factor. This study evaluated type 2 diabetes outpatients in a hospital in Vietnam for drug-related problems (DRPs) and related variables.MethodsA cross-sectional descriptive study was conducted on 495 outpatients who met the criteria and 157 people agreed to participate in the interview. Medication order review and medication adherence review were used to identify DRPs. The types of DRP were based on the Pharmaceutical Care Network Europe (PCNE) categories version 9.0. The identification and assessment DRPs were carried out by clinical pharmacists and get agreed upon by physicians who had not directly prescribed patients who participated in the study.ResultsA total of 762 DRPs were identified via prescribing review process, the average number of DRP on each prescription was 1.54±1.07, while 412 DRPs were determined through patient interviewing. The most frequent DRPs were "ADR (Adverse Drug Reaction) occurring" (68.8%). The main causes were "patient is unable to understand instructions properly" or "patient is not properly instructed", "patient stores insulin inappropriately", "patient decides to use unnecessary drugs" and "patient intentionally uses/takes less drug than prescribed or does not take the drug at all for whatever reason" which accounted for 65.0%, 41.4%, 38.2%, and 28.7%, respectively. From the prescribing review, the most observed DRPs were "Inappropriate drug according to guidelines/formulary" and "No or incomplete drug treatment in spite of existing indication", accounting for 45.0% and 42.9%, respectively. There was a significant association between age (OR 3.38, 95% CI: 1.01-11.30), duration of diabetes (OR 3.61, 95%CI: 1.11-11.74), presence of comorbidity (OR 5.31, 95%CI: 1.97-14.30), polypharmacy (OR: 2.95, 95%CI: 1.01-8.72) and DRPs. In patients, poor knowledge of antidiabetic agents was the main reason to lack adherence and occurring ADR (OR 2.73, 95%CI: 1.32-5.66, p = 0.007 and OR 2.49, 95%CI: 1.54-4.03, p = 0.001 respectively).ConclusionDRPs occurred in the prescribing stage and relating to patient's behavior of drug administration was high. Clear identification of DRPs and the associated factors are essential for building the intervention process to improve effectiveness and safety in the treatment of type 2 diabetes mellitus patients

Alcohol and tobacco use among methadone maintenance patients in Vietnamese rural mountainside areas

Introduction: The expansion of methadone maintenance treatment (MMT) program requires more data about the factors affecting the effectiveness of treatment, especially behavioral data such as smoking and alcohol use among patients. This study aimed to examine the prevalence of tobacco and alcohol consumption and identify related factors among MMT patients in the Vietnamese rural mountainside. Methods: We interviewed 241 MMT patients in two clinics in Tuyen Quang, a mountainous province in Vietnam. Patients were asked to report the smoking status (current smoker or not), nicotine dependence (by Fagerström test for nicotine dependence - FTND) and alcohol use (by using the Alcohol Use Disorders Identification Test – AUDIT-C). EuroQol-5 dimensions-5 levels (EQ-5D-5L) and EQ-Visual analogue scale (EQ-VAS) were employed to measure health-related quality of life. Multivariate logistic and Tobit regressions were used to identify the associated factors. Results: The majority of respondents were current smokers (75.7%) and a low proportion were hazardous drinkers (18.3%). People receiving treatment in a rural clinic (OR = 0.45; 95%CI = 0.22–0.92) and had problems in usual activities (OR = 0.20; 95%CI = 0.06–0.70) were less likely to be smokers. Q-VAS score (Coef. = 0.03; 95%CI = 0.02–0.05) and having problems in mobility (Coef. = 0.72; 95%CI = 0.03–1.42) was found to be associated with the increase of nicotine dependence. In terms of alcohol drinking, people with other jobs were more likely to drink hazardously compared to unemployed patients (OR = 2.86; 95%CI = 1.20–6.82). Similarly, patients having higher duration of MMT had higher likelihood of being hazardous drinkers (OR = 1.07; 95%CI = 1.01–1.13). Conclusions: This study highlights the low rate of alcohol abusers but a considerably high proportion of current smokers among MMT patients in the rural mountainside area. Alcohol and tobacco counseling programs combined with social and family support also play an essential role in alcohol and tobacco control. In addition, implementing mass community-based behavioral change campaigns to reduce drug addiction-related stigmatization should also be prioritized.Published versio