The dilemma of improving rational antibiotic use in pediatric community-acquired pneumonia.

Pneumonia is the number one cause of disease and deaths in children under five years old, outside the neonatal period, with the greatest number of cases reported from resource-limited settings. The etiology is variable, with not much information on the local etiology drug resistance profile in many countries. Recent studies suggest an increasing contribution from respiratory viruses, also in children with severe pneumonia, with an increased relative contribution in settings that have good vaccine coverage against common bacterial pathogens. Respiratory virus circulation was greatly reduced during highly restrictive measures to contain the spread of COVID-19 but rebounded once COVID-19 restrictions were relaxed. We conducted a comprehensive literature review of the disease burden, pathogens, case management and current available prevention of community acquired childhood pneumonia, with a focus on rational antibiotic use, since the treatment of respiratory infections is the leading cause of antibiotic use in children. Consistent application of revised World Health Organisation (WHO) guidance that children presenting with coryzal symptoms or wheeze can be managed without antibiotics in the absence of fever, will help to reduce unnecessary antibiotic use, as will increased availability and use of bedside inflammatory marker tests, such as C-reactive protein (CRP) in children with respiratory symptoms and fever.

Series of M-MOF-184 (M = Mg, Co, Ni, Zn, Cu, Fe) Metal-Organic Frameworks for Catalysis Cycloaddition of CO2.

In light of the chemical exploitation of CO2, new reusable materials for efficiently catalyzing the cycloaddition of CO2 and epoxides under moderate conditions are needed. Herein, a new series of isostructural metal-organic frameworks (MOFs) M2(EDOB) [EDOB4- = 4,4'-(ethyne-1,2-diyl)bis(2-oxidobenzoate), M = Mg, Ni, Co, Zn, Cu, Fe], known as M-MOF-184, analogous to a well-studied MOF-74 structure, were synthesized and fully characterized. The M-MOF-184 (M = Mg, Co, Ni, Zn) frameworks exhibit accessible mesopore channels (24 Å) and high porosity. Among them, Mg-MOF-184 demonstrated the most upper surface area (>4000 m2 g-1) in any reported MOF-74-type frameworks. Furthermore, Co-MOF-184 revealed the highest CO2 uptake (73 cm3 g-1, at 298 K), and Zn-MOF-184 showed the highest catalytic activity upon the cycloaddition of CO2 (96% conversion, 86% selectivity, and 82% yield) under mild conditions (1 atm CO2, 80 °C, 6 h, and solvent-free). Notably, the catalytic performance of Zn-MOF-184 outperformed that of the original M-MOF-74 (M = Mg, Co, Zn) materials and various Zn-based MOFs. To evaluate the acidity and basicity of a series of M-MOF-184 (M = Mg, Co, Ni, Zn) frameworks, the interaction of these MOFs with acetonitrile vapor was investigated by vapor adsorption and ATR-FTIR spectroscopy measurements. As such, Zn-MOF-184 showed the strongest Lewis acidity derived by Zn cations, which was correlated to the highest catalytic activity upon the cycloaddition of CO2. Interestingly, the 2-oxidobenzoate anions from Co-MOF-184 showed the strongest basicity among the series, which was associated with the highest saturated acetonitrile uptake (544 cm3 g-1 at 298 K). Our findings suggest that the integration of Lewis acidic and basic sites, high surface area, and large accessible pores into the framework can facilitate the CO2 fixation reaction.

Predictors of Unlikely Bacterial Pneumonia and Adverse Pneumonia Outcome in Children Admitted to a Hospital in Central Vietnam.

BACKGROUND: Pneumonia is the leading cause of antibiotic use and hospitalization in Vietnam. There is a need for better prediction of unlikely bacterial pneumonia and adverse pneumonia outcome in order to guide hospital admission and improve rational antibiotic use. METHODS: All children under 5 admitted with pneumonia (per clinician assessment) to the Da Nang Hospital for Women and Children were prospectively enrolled. Children were classified as having likely or unlikely bacterial pneumonia and followed for outcome assessment. A Bayesian model averaging approach was used to identify predictors of unlikely bacterial pneumonia and adverse pneumonia outcome, which guided the development of a pragmatic management algorithm. RESULTS: Of 3817 patients assessed, 2199 (57.6%) met World Health Organization (WHO) pneumonia criteria. In total, 1594 (41.7%) children were classified as having unlikely and 129 (3.4%) as having likely bacterial pneumonia. The remainder (2399; 62.9%) were considered to have disease of uncertain etiology. Factors predictive of unlikely bacterial pneumonia were no fever, no consolidation on chest radiograph, and absolute neutrophil count <5 × 109/L at presentation, which had a negative predictive value (NPV) for likely bacterial pneumonia of 99.0%. Among those who met WHO pneumonia criteria, 8.6% (189/2199) experienced an adverse outcome. Not having any WHO danger sign or consolidation on chest radiograph had an NPV of 96.8% for adverse pneumonia outcome. CONCLUSIONS: An algorithm that screens for predictors of likely bacterial pneumonia and adverse pneumonia outcome could reduce unnecessary antibiotic use and hospital admission, but its clinical utility requires validation in a prospective study.

High prevalence of colonisation with carbapenem-resistant Enterobacteriaceae among patients admitted to Vietnamese hospitals: Risk factors and burden of disease.

BACKGROUND: Carbapenem-resistant Enterobacteriaceae (CRE) is an increasing problem worldwide, but particularly problematic in low- and middle-income countries (LMIC) due to limitations of resources for surveillance of CRE and infection prevention and control (IPC). METHODS: A point prevalence survey (PPS) with screening for colonisation with CRE was conducted on 2233 patients admitted to neonatal, paediatric and adult care at 12 Vietnamese hospitals located in northern, central and southern Vietnam during 2017 and 2018. CRE colonisation was determined by culturing of faecal specimens on selective agar for CRE. Risk factors for CRE colonisation were evaluated. A CRE admission and discharge screening sub-study was conducted among one of the most vulnerable patient groups; infants treated at an 80-bed Neonatal ICU from March throughout June 2017 to assess CRE acquisition, hospital-acquired infection (HAI) and treatment outcome. RESULTS: A total of 1165 (52%) patients were colonised with CRE, most commonly Klebsiella pneumoniae (n = 805), Escherichia coli (n = 682) and Enterobacter spp. (n = 61). Duration of hospital stay, HAI and treatment with a carbapenem were independent risk factors for CRE colonisation. The PPS showed that the prevalence of CRE colonisation increased on average 4.2% per day and mean CRE colonisation rates increased from 13% on the day of admission to 89% at day 15 of hospital stay. At the NICU, CRE colonisation increased from 32% at admission to 87% at discharge, mortality was significantly associated (OR 5·5, P < 0·01) with CRE colonisation and HAI on admission. CONCLUSION: These data indicate that there is an epidemic spread of CRE in Vietnamese hospitals with rapid transmission to hospitalised patients.

Characterisation of children hospitalised with pneumonia in central Vietnam: a prospective study.

Pneumonia is the most common reason for paediatric hospital admission in Vietnam. The potential value of using the World Health Organization (WHO) case management approach in Vietnam has not been documented.We performed a prospective descriptive study of all children (2-59 months) admitted with "pneumonia" (as assessed by the admitting clinician) to the Da Nang Hospital for Women and Children to characterise their disease profiles and assess risk factors for an adverse outcome. The disease profile was classified using WHO pneumonia criteria, with tachypnoea or chest indrawing as defining clinical signs. Adverse outcome was defined as death, intensive care unit admission, tertiary care transfer or hospital stay >10 days.Of 4206 admissions, 1758 (41.8%) were classified as "no pneumonia" using WHO criteria and only 252 (6.0%) met revised criteria for "severe pneumonia". The inpatient death rate was low (0.4% of admissions) with most deaths (11 out of 16; 68.8%) occurring in the "severe pneumonia" group. An adverse outcome was recorded in 18.7% of all admissions and 60.7% of the "severe pneumonia" group. Children were hospitalised for a median of 7 days at an average cost of 253 USD per admission. Risk factors for adverse outcome included WHO-classified "severe pneumonia", age <1 year, low birth weight, previous recent admission with an acute respiratory infection and recent tuberculosis exposure. Breastfeeding, day-care attendance and pre-admission antibiotic use were associated with reduced risk.Few hospital admissions met WHO criteria for "severe pneumonia", suggesting potential unnecessary hospitalisation and use of intravenous antibiotics. Better characterisation of the underlying diagnosis requires careful consideration.

A Cerium-Containing Metal-Organic Framework: Synthesis and Heterogeneous Catalytic Activity toward Fenton-Like Reactions.

A cerium-based metal-organic framework, namely MOF-589, was synthesized using benzoimidephenanthroline tetracarboxylic acid (H4 BIPA-TC) as an organic linker. Full characterization including single-crystal and powder X-ray diffraction analysis, thermogravimetrical analysis, scanning electron microscopy, and N2 adsorption measurements at low pressure and 77 K were carried out. The material was employed as an efficient heterogeneous catalyst for decomposition of methylene blue (MB) dye (40 ppm) in the presence of H2 O2 in 15 minutes. Interestingly, comparison studies showed that the activity of MOF 589 was higher than that of other iron-based heterogeneous and cerium-based catalysts. Further experiments to clarify the MOF 589 activity indicated that the BIPA-TC linker might have an important impact through a cooperative effect on the metal cluster. Control studies confirmed that the presence of catalyst was necessary for the reaction to occur and the catalyst recyclability. In particular, catalysis from leached cerium in the reaction filtrate is unlikely and the solid material could be reused at least eight times without a remarkable loss in activity.

An Infant with Xpert® Confirmed TB Meningitis in Central Viet Nam.

A 5-month-old boy presented with a focal seizure. Disseminated (miliary) tuberculosis (TB) was diagnosed on chest radiograph and TB meningitis was confirmed using Xpert MTB/RIF®. The case represents the first instance of cerebrospinal fluid Xpert MTB/RIF® testing in children in central Viet Nam. Family screening diagnosed the father with sputum smear-positive TB. The mother and a 2-year-old sibling had no symptoms or signs of TB disease and started preventive therapy. Early TB meningitis diagnosis is the single most important factor influencing clinical outcome, but is difficult due to the non-specific signs and symptoms at disease onset. Late diagnosis is associated with high mortality and severe neurologic handicap, which emphasizes the value of TB preventive therapy in vulnerable young children in close contact with an infectious TB case (recent is generally defined as within the last 12 months).

A Series of Metal-Organic Frameworks for Selective CO2 Capture and Catalytic Oxidative Carboxylation of Olefins.

Three new lanthanide-based metal-organic frameworks (Ln-MOFs), namely MOF-590, -591, and -592 constructed from a tetratopic linker, benzoimidephenanthroline tetracarboxylic acid (H4BIPA-TC), were synthesized under solvothermal conditions and fully characterized. All of the new MOFs exhibit three-dimensional frameworks, which adopt unprecedented topologies in MOF field. Gas adsorption measurements of MOF-591 and -592 revealed good adsorption of CO2 (low pressure, at room temperature) and moderate CO2 selectivity over N2 and CH4. Consequently, breakthrough experiments illustrated the separation of CO2 from binary mixture of CO2 and N2 with the use of MOF-592. Accordingly, MOF-592 revealed the selective CO2 capture effectively without any loss in performance after three cycles. Moreover, MOF-590, -591, and -592 showed to be catalytically active in the oxidative carboxylation of styrene and CO2 for a one-pot synthesis of styrene carbonate under mild conditions (1 atm CO2, 80 °C, and without solvent). Among the new materials, MOF-590 revealed a remarkable efficiency with exceptional conversion (96%), selectivity (95%), and yield (91%).

New Metal-Organic Frameworks for Chemical Fixation of CO2.

A novel series of two zirconium- and one indium-based metal-organic frameworks (MOFs), namely, MOF-892, MOF-893, and MOF-894, constructed from the hexatopic linker, 1',2',3',4',5',6'-hexakis(4-carboxyphenyl)benzene, were synthesized and fully characterized. MOF-892 and MOF-893 are two new exemplars of materials with topologies previously unseen in the important family of zirconium MOFs. MOF-892, MOF-893, and MOF-894 exhibit efficient heterogeneous catalytic activity for the cycloaddition of CO2, resulting in a cyclic organic carbonate formation with high conversion, selectivity, and yield under mild conditions (1 atm CO2, 80 °C, and solvent-free). Because of the structural features provided by their building units, MOF-892 and MOF-893 are replete with accessible Lewis and Brønsted acid sites located at the metal clusters and the non-coordinating carboxylic groups of the linkers, respectively, which is found to promote the catalytic CO2 cycloaddition reaction. As a proof-of-concept, MOF-892 exhibits high catalytic activity in the one-pot synthesis of styrene carbonate from styrene and CO2 without preliminary synthesis and isolation of styrene oxide.

Synthesis and Selective CO2 Capture Properties of a Series of Hexatopic Linker-Based Metal-Organic Frameworks.

Four crystalline, porous metal-organic frameworks (MOFs), based on a new hexatopic linker, 1',2',3',4',5',6'-hexakis(4-carboxyphenyl)benzene (H6CPB), were synthesized and fully characterized. Interestingly, two members of this series exhibited new topologies, namely, htp and hhp, which were previously unseen in MOF chemistry. Gas adsorption measurements revealed that all members exhibited high CO2 selectivity over N2 and CH4. Accordingly, breakthrough measurements were performed on a representative example, in which the effective separation of CO2 from binary mixtures containing either N2 or CH4 was demonstrated without any loss in performance over three consecutive cycles.

Virological characterization of influenza H1N1pdm09 in Vietnam, 2010-2013.

OBJECTIVES: Influenza A/H1N1pdm09 virus was first detected in Vietnam on May 31, 2009, and continues to circulate in Vietnam as a seasonal influenza virus. This study has monitored genotypic and phenotypic changes in this group of viruses during 2010-2013 period. DESIGN AND SETTING: We sequenced hemagglutinin (HA) and neuraminidase (NA) genes from representative influenza A/H1N1pdm09 and compared with vaccine strain A/California/07/09 and other contemporary isolates from neighboring countries. Hemagglutination inhibition (HI) and neuraminidase inhibition (NAI) assays also were performed on these isolates. SAMPLE: Representative influenza A/H1N1pdm09 isolates (n = 61) from ILI and SARI surveillances in northern Vietnam between 2010 and 2013. MAIN OUTCOME MEASURES AND RESULTS: The HA and NA phylogenies revealed six and seven groups, respectively. Five isolates (8·2%) had substitutions G155E and N156K in the HA, which were associated with reduced HI titers by antiserum raised against the vaccine virus A/California/07/2009. One isolate from 2011 and one isolate from 2013 had a predicted H275Y substitution in the neuraminidase molecule, which was associated with reduced susceptibility to oseltamivir in a NAI assay. We also identified a D222N change in the HA of a virus isolated from a fatal case in 2013. CONCLUSIONS: Significant genotypic and phenotypic changes in A/ H1N1pdm09 influenza viruses were detected by the National Influenza Surveillance System (NISS) in Vietnam between 2010 and 2013 highlighting the value of this system to Vietnam and to the region. Sustained NISS and continued virological monitoring of seasonal influenza viruses are required for vaccine policy development in Vietnam. 3.