Metalloporphyrin-Based Metal–Organic Framework Nanorods for Peroxidase-Like Catalysis

Metal–organic frameworks (MOFs) and their derivatives are emerging biosensing platforms due to their rational structural optimization. Herein, several metalloporphyrin–Porous Coordinated Network-222 (M-PCN-222) are developed for composition-dependent hydrogen peroxide (H2O2) sensing. A typical colorimetric sensing method (via a 3,3′,5,5′-tetramethylbenzidine-induced allochroic reaction) is employed to investigate the intrinsic peroxidase activity of M-PCN-222 (M = Mn, Fe, Co, and Ni). Fe-PCN-222 affords high sensitivity, good selectivity, robust stability, and a widely applicable concentration range. Theoretical investigations of active sites reveal that such different performances stem from the OH* binding on the M-PCN-222 surface. In addition, the adsorption energy of OH* on Fe-PCN-222 is similar to that of natural horseradish peroxidase. Molecular dynamics simulations are performed on Fe-PCN-222 nanorods to study the catalytic process of H2O2 based on their abundant micropores and mesopores. The obtained results suggest that the porphyrinic Fe-PCN-222 nanorod-based colorimetric sensing of H2O2 has great potential in catalysis, biosensors, and food industries

Metalloporphyrin-Based Metal–Organic Framework Nanorods for Peroxidase-Like Catalysis

Metal–organic frameworks (MOFs) and their derivatives are emerging biosensing platforms due to their rational structural optimization. Herein, several metalloporphyrin–Porous Coordinated Network-222 (M-PCN-222) are developed for composition-dependent hydrogen peroxide (H2O2) sensing. A typical colorimetric sensing method (via a 3,3′,5,5′-tetramethylbenzidine-induced allochroic reaction) is employed to investigate the intrinsic peroxidase activity of M-PCN-222 (M = Mn, Fe, Co, and Ni). Fe-PCN-222 affords high sensitivity, good selectivity, robust stability, and a widely applicable concentration range. Theoretical investigations of active sites reveal that such different performances stem from the OH* binding on the M-PCN-222 surface. In addition, the adsorption energy of OH* on Fe-PCN-222 is similar to that of natural horseradish peroxidase. Molecular dynamics simulations are performed on Fe-PCN-222 nanorods to study the catalytic process of H2O2 based on their abundant micropores and mesopores. The obtained results suggest that the porphyrinic Fe-PCN-222 nanorod-based colorimetric sensing of H2O2 has great potential in catalysis, biosensors, and food industries

Metalloporphyrin-Based Metal–Organic Framework Nanorods for Peroxidase-Like Catalysis

Metal–organic frameworks (MOFs) and their derivatives are emerging biosensing platforms due to their rational structural optimization. Herein, several metalloporphyrin–Porous Coordinated Network-222 (M-PCN-222) are developed for composition-dependent hydrogen peroxide (H2O2) sensing. A typical colorimetric sensing method (via a 3,3′,5,5′-tetramethylbenzidine-induced allochroic reaction) is employed to investigate the intrinsic peroxidase activity of M-PCN-222 (M = Mn, Fe, Co, and Ni). Fe-PCN-222 affords high sensitivity, good selectivity, robust stability, and a widely applicable concentration range. Theoretical investigations of active sites reveal that such different performances stem from the OH* binding on the M-PCN-222 surface. In addition, the adsorption energy of OH* on Fe-PCN-222 is similar to that of natural horseradish peroxidase. Molecular dynamics simulations are performed on Fe-PCN-222 nanorods to study the catalytic process of H2O2 based on their abundant micropores and mesopores. The obtained results suggest that the porphyrinic Fe-PCN-222 nanorod-based colorimetric sensing of H2O2 has great potential in catalysis, biosensors, and food industries

Studies included in the systematic review and meta-analysis.

a<p>WHO regions: AFR: Africa; AMR: Americas; EMR: Eastern Mediterrean; EUR: Europe; SEAR: Southeast Asia; WPR: Western Pacific.</p

Characteristics of included studies.

<p>Numbers provided are <i>n</i> (%) unless otherwise specified. IQR, interquartile range; RCT, randomized controlled trial.</p

Risk of Early-Onset Neonatal Infection with Maternal Infection or Colonization: A Global Systematic Review and Meta-Analysis

<div><p>Background</p><p>Neonatal infections cause a significant proportion of deaths in the first week of life, yet little is known about risk factors and pathways of transmission for early-onset neonatal sepsis globally. We aimed to estimate the risk of neonatal infection (excluding sexually transmitted diseases [STDs] or congenital infections) in the first seven days of life among newborns of mothers with bacterial infection or colonization during the intrapartum period.</p><p>Methods and Findings</p><p>We searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, and the World Health Organization Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection published from January 1, 1960 to March 30, 2013. Studies were included that reported effect measures on the risk of neonatal infection among newborns exposed to maternal infection. Random effects meta-analyses were used to pool data and calculate the odds ratio estimates of risk of infection. Eighty-three studies met the inclusion criteria. Seven studies (8.4%) were from high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of laboratory-confirmed and clinical signs of infection, as well as for colonization and risk factors. The odds ratio for neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 6.6 (95% CI 3.9–11.2). Newborns of mothers with colonization had a 9.4 (95% CI 3.1–28.5) times higher odds of lab-confirmed infection than newborns of non-colonized mothers. Newborns of mothers with risk factors for infection (defined as prelabour rupture of membranes [PROM], preterm <37 weeks PROM, and prolonged ROM) had a 2.3 (95% CI 1.0–5.4) times higher odds of infection than newborns of mothers without risk factors.</p><p>Conclusions</p><p>Neonatal infection in the first week of life is associated with maternal infection and colonization. High-quality studies, particularly from settings with high neonatal mortality, are needed to determine whether targeting treatment of maternal infections or colonization, and/or prophylactic antibiotic treatment of newborns of high risk mothers, may prevent a significant proportion of early-onset neonatal sepsis.</p><p><i>Please see later in the article for the Editors' Summary</i></p></div

Flow diagram of study selection.

<p>Flow diagram of study selection.</p

Maternal colonization and neonatal colonization.

<p>Maternal colonization and neonatal colonization.</p

Maternal risk factors and neonatal infection.

<p>*Adjusted ORs. These studies provided estimates adjusted for confounding factors.</p

Regression analysis of the effect of explanatory variables on the risk of transmission (early-onset).

a<p>Regression coefficient from metaregression.</p