A Multi-Center Randomised Controlled Trial of Gatifloxacin versus Azithromycin for the Treatment of Uncomplicated Typhoid Fever in Children and Adults in Vietnam

BACKGROUND: Drug resistant typhoid fever is a major clinical problem globally. Many of the first line antibiotics, including the older generation fluoroquinolones, ciprofloxacin and ofloxacin, are failing. OBJECTIVES: We performed a randomised controlled trial to compare the efficacy and safety of gatifloxacin (10 mg/kg/day) versus azithromycin (20 mg/kg/day) as a once daily oral dose for 7 days for the treatment of uncomplicated typhoid fever in children and adults in Vietnam. METHODS: An open-label multi-centre randomised trial with pre-specified per protocol analysis and intention to treat analysis was conducted. The primary outcome was fever clearance time, the secondary outcome was overall treatment failure (clinical or microbiological failure, development of typhoid fever-related complications, relapse or faecal carriage of S. typhi). PRINCIPAL FINDINGS: We enrolled 358 children and adults with suspected typhoid fever. There was no death in the study. 287 patients had blood culture confirmed typhoid fever, 145 patients received gatifloxacin and 142 patients received azithromycin. The median FCT was 106 hours in both treatment arms (95% Confidence Interval [CI]; 94-118 hours for gatifloxacin versus 88-112 hours for azithromycin), (logrank test p = 0.984, HR [95% CI] = 1.0 [0.80-1.26]). Overall treatment failure occurred in 13/145 (9%) patients in the gatifloxacin group and 13/140 (9.3%) patients in the azithromycin group, (logrank test p = 0.854, HR [95% CI] = 0.93 [0.43-2.0]). 96% (254/263) of the Salmonella enterica serovar Typhi isolates were resistant to nalidixic acid and 58% (153/263) were multidrug resistant. CONCLUSIONS: Both antibiotics showed an excellent efficacy and safety profile. Both gatifloxacin and azithromycin can be recommended for the treatment of typhoid fever particularly in regions with high rates of multidrug and nalidixic acid resistance. The cost of a 7-day treatment course of gatifloxacin is approximately one third of the cost of azithromycin in Vietnam. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN67946944

An Outbreak of Severe Infections with Community-Acquired MRSA Carrying the Panton-Valentine Leukocidin Following Vaccination

Background: Infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging worldwide. We investigated an outbreak of severe CA-MRSA infections in children following out-patient vaccination. Methods and Findings: We carried out a field investigation after adverse events following immunization (AEFI) were reported. We reviewed the clinical data from all cases. S. aureus recovered from skin infections and from nasal and throat swabs were analyzed by pulse-field gel electrophoresis, multi locus sequence typing, PCR and microarray. In May 2006, nine children presented with AEFI, ranging from fatal toxic shock syndrome, necrotizing soft tissue infection, purulent abscesses, to fever with rash. All had received a vaccination injection in different health centres in one District of Ho Chi Minh City. Eight children had been vaccinated by the same health care worker (HCW). Deficiencies in vaccine quality, storage practices, or preparation and delivery were not found. Infection control practices were insufficient. CA-MRSA was cultured in four children and from nasal and throat swabs from the HCW. Strains from children and HCW were indistinguishable. All carried the Panton-Valentine leukocidine (PVL), the staphylococcal enterotoxin B gene, the gene complex for staphylococcal-cassette-chromosome mec type V, and were sequence type 59. Strain HCM3A is epidemiologically unrelated to a strain of ST59 prevalent in the USA, althoughthey belong to the same lineage. Conclusions. We describe an outbreak of infections with CA-MRSA in children, transmitted by an asymptomatic colonized HCW during immunization injection. Consistent adherence to injection practice guidelines is needed to prevent CA-MRSA transmission in both in- and outpatient settings

Candlestick analysis in U.S. stock market.

In this thesis, we conduct the study of the predictive power of candlestick patterns. We use the daily prices (open, high, low, and close) of all active stocks that are listed on New York Stock Exchange (NYSE) for the 34-year period from 1973 to 2007 to perform various statistical tests.The results provide evidence that traders are influenced by price behaviours

Time Scheduling and Energy Trading for Heterogeneous Wireless-Powered and Backscattering-Based IoT Networks

This article studies the strategic interactions between an IoT service provider (IoTSP) which consists of heterogeneous IoT devices and its energy service provider (ESP). To that end, we propose an economic framework using the Stackelberg game to maximize the network throughput and energy efficiency of both the IoTSP and ESP. To obtain the Stackelberg equilibrium (SE), we apply a backward induction technique which first derives a closed-form solution for the ESP (follower). Then, to tackle the non-convex optimization problem for the IoTSP (leader), we leverage the block coordinate descent and convex-concave procedure techniques to design two partitioning schemes (i.e., partial adjustment (PA) and joint adjustment (JA)) to find the optimal energy price and service time that constitute local SEs. Numerical results reveal that by jointly optimizing the energy trading and time allocation for IoT devices, one can achieve significant improvements in terms of the IoTSP’s profit compared with those of conventional transmission methods (up to 38.7 folds). Different tradeoffs between the ESP’s and IoTSP’s profits and complexities of the PA/JA schemes can also be numerically tuned. Simulations also show that the obtained local SEs approach the optimal social welfare when the benefit per transmitted bit exceeds a given threshold

Time Scheduling and Energy Trading for Heterogeneous Wireless-Powered and Backscattering-Based IoT Networks

This article studies the strategic interactions between an IoT service provider (IoTSP) which consists of heterogeneous IoT devices and its energy service provider (ESP). To that end, we propose an economic framework using the Stackelberg game to maximize the network throughput and energy efficiency of both the IoTSP and ESP. To obtain the Stackelberg equilibrium (SE), we apply a backward induction technique which first derives a closed-form solution for the ESP (follower). Then, to tackle the non-convex optimization problem for the IoTSP (leader), we leverage the block coordinate descent and convex-concave procedure techniques to design two partitioning schemes (i.e., partial adjustment (PA) and joint adjustment (JA)) to find the optimal energy price and service time that constitute local SEs. Numerical results reveal that by jointly optimizing the energy trading and time allocation for IoT devices, one can achieve significant improvements in terms of the IoTSP’s profit compared with those of conventional transmission methods (up to 38.7 folds). Different tradeoffs between the ESP’s and IoTSP’s profits and complexities of the PA/JA schemes can also be numerically tuned. Simulations also show that the obtained local SEs approach the optimal social welfare when the benefit per transmitted bit exceeds a given threshold

Frequency-Dependent Contrast Enhancement for Conductive and Non-Conductive Materials in Electrical Impedance Tomography

This research investigates the critical role of frequency selection in Electrical Impedance Tomography (EIT), a non-invasive imaging technique that reconstructs internal conductivity distributions through injected electrical currents. Empirical frequency selection is paramount to maximizing the fidelity and specificity of EIT images. The study explores the impact of distinct frequency ranges—low, medium, and high—on image contrast and clarity, particularly focusing on differentiating conductive materials from non-conductive materials. The findings reveal distinct empirical frequency bands for enhancing the respective contrasts: 15–38 kHz for conductive materials (copper) and 45–75 kHz for non-conductive materials (acrylic resin). These insights shed light on the frequency-dependent nature of material contrast in EIT images, guiding the selection of empirical operating ranges for various target materials. This research paves the way for improved sensitivity and broader applicability of EIT in diverse areas

Hepatoprotection and Phytochemistry of the Vietnamese Herbs Cleome chelidonii and Cleome viscosa Stems

The study aims to determine the hepatoprotective effect of n-hexane, ethyl acetate, and methanol extracts of the leaves and stems of two Cleome species against carbon tetrachloride- (CCl4-) induced liver toxicity both in vitro using human hepatoma (HepG2) cells and in vivo in rats as well as the hepatoprotective property of all isolated compounds on HepG2. After 72 h of treatment, at the concentrations of 25, 50, and 100 μg/mL, the methanol of C. chelidonii stems (CCSM) ranged from 18.6% to 20.8%, whereas the methanol of C. chelidonii stems (CVSM) increased from 12.3% to 17.2% cell viability. The results show that CCSM and CVSM significantly expressed in vitro hepaprotective activity on HepG2. Therefore, the animals were daily treated with these extracts at the doses of 15, 30, and 45 mg/kg body weight for 5 days, and CCl4 was injected (2 ml/kg body weight, i.p.) on the 2nd and 3rd days. Levels of aspartate aminotransferase (ALT) and alanine aminotransferase (AST) in the blood were measured and compared to the silymarin control. The treatments with CCSM and CVSM (30, and 45 mg/kg) possessed significant hepatoprotection and were comparable with the activity of silymarin. Further, phytochemical studies of these ones were conducted and led to the identification of eight flavonoids: visconoside A (1), visconoside B (2), quercetin 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (4), cleomeside A (5), cleomeside B (6), cleomeside C (7), and quercetin-3-O-[β-D-glucopyranosyl-(1⟶2)]-α-L-rhamnopyranoside 7-O-α-L-rhamnopyranoside (8). Two major flavonoids (1 and 4) displayed significant hepatoprotective property (at the concentration of 100 μM, the prevention percentage values were 66.5% and 74.2%, respectively, compared to the quercetin control, with value of 80.3%)

Study of a Strong Luminescent Core Shell Nanocomposite of Europium Complex Coated on Gold Nanoparticles: Synthesis and Properties

International audienc

Anthropogenic particle abundance and characteristics in seawater and intertidal sediments of the Tonkin Bay Coast (North Vietnam)

International audienceMicroplastics (MPs, plastic items from 1 µm to 5 mm in size) are present in all environmental compartments. The evaluation of their concentration, fate, and spatial distribution is still a challenge for the scientific community. This concern is just debuting in developing countries, (i.e., Asia, South America, and Africa). This study deals with the MP contamination in the abiotic marine compartments of Northern Vietnam: seawater and intertidal sediments. Four sites located in the intertidal zone or near the coastline in Tonkin Bay, Vietnam were studied. A total of 16 samples (eight for each compartment) were collected in July 2020 (rainy season) and January 2021 (dry season). Anthropogenic particles (total observed fibers and fragments) were found at levels ranging from 3 to 303 particles/m3 in seawater and from 63 to 955 particles/kg dry weight in sediments. Most of these were fibers less than 300-µm long. Higher levels of seawater at the Nam Dinh site were found in the rainy season compared to the dry one. As the river flow was estimated six times higher during the rainy season than during the dry season, these results suggest the river discharge is a potential source of contamination for the coastal zone. The temporal variability was lower for the sediments than for the seawater, suggesting the long-term integration of the anthropogenic particles in this compartment. A small portion of sorted particles were analyzed by µFTIR (8.35%), and this sub-sample was only composed of fragments. Still, fragments were mostly composed of polypropylene (PP, 82%), polyethylene (PE, 9%), and polystyrene (PS, 9%). The fragment size was similar in the two studied compartments, but it was dependent on polymer types since PS fragments (140 ± 17 µm) were smaller than those made of PE (622 ± 123 µm) and PP (869 ± 905 µm). Future works should investigate the smallest fraction of MP (even nanoplastics) as well as find solutions in order to mitigate MP contamination in the marine environment