Assessing meso- and microplastic pollution in the Ligurian and Tyrrhenian Seas

As the production of plastic products continues to increase, determining the fate of plastic waste in the environment is of high importance. Densely populated areas, such as Mediterranean coastlines, represent locations of high pollution risk for surrounding environments. Thus, this study aims to assess the abundance, size, and composition of floating meso- and microplastics collected during four weeks in 2018 in the Ligurian and Tyrrhenian Seas. The results show average meso- and microplastic particle concentrations of 28,376 ± 28,917 particles km−2, and an average mass of 268.61 ± 421.18 g km−2. The particle shape ratio was 65% fragments, 19% films, 10% lines, 4% foams, and 2% pellets. Microplastic particles comprised 65% of the sample. Analysis with attenuated total reflection Fourier transform infrared spectroscopy showed predominant polymer types included polyethylene, polypropylene, polystyrene, and polyamide. These data are an important starting point for long-term monitoring of plastic pollution levels within this region

Structure of the ATP synthase from Mycobacterium smegmatis provides targets for treating tuberculosis.

The structure has been determined by electron cryomicroscopy of the adenosine triphosphate (ATP) synthase from Mycobacterium smegmatis This analysis confirms features in a prior description of the structure of the enzyme, but it also describes other highly significant attributes not recognized before that are crucial for understanding the mechanism and regulation of the mycobacterial enzyme. First, we resolved not only the three main states in the catalytic cycle described before but also eight substates that portray structural and mechanistic changes occurring during a 360° catalytic cycle. Second, a mechanism of auto-inhibition of ATP hydrolysis involves not only the engagement of the C-terminal region of an α-subunit in a loop in the γ-subunit, as proposed before, but also a "fail-safe" mechanism involving the b'-subunit in the peripheral stalk that enhances engagement. A third unreported characteristic is that the fused bδ-subunit contains a duplicated domain in its N-terminal region where the two copies of the domain participate in similar modes of attachment of the two of three N-terminal regions of the α-subunits. The auto-inhibitory plus the associated "fail-safe" mechanisms and the modes of attachment of the α-subunits provide targets for development of innovative antitubercular drugs. The structure also provides support for an observation made in the bovine ATP synthase that the transmembrane proton-motive force that provides the energy to drive the rotary mechanism is delivered directly and tangentially to the rotor via a Grotthuss water chain in a polar L-shaped tunnel

Structure of the NDH-2 - HQNO inhibited complex provides molecular insight into quinone-binding site inhibitors.

Type II NADH:quinone oxidoreductase (NDH-2) is a proposed drug-target of major pathogenic microorganisms such as Mycobacterium tuberculosis and Plasmodium falciparum. Many NDH-2 inhibitors have been identified, but rational drug development is impeded by the lack of information regarding their mode of action and associated inhibitor-bound NDH-2 structure. We have determined the crystal structure of NDH-2 complexed with a quinolone inhibitor 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO). HQNO is nested into the slot-shaped tunnel of the Q-site, in which the quinone-head group is clamped by Q317 and I379 residues, and hydrogen-bonds to FAD. The interaction of HQNO with bacterial NDH-2 is very similar to the native substrate ubiquinone (UQ1) interactions in the yeast Ndi1-UQ1 complex structure, suggesting a conserved mechanism for quinone binding. Further, the structural analysis provided insight how modifications of quinolone scaffolds improve potency (e.g. quinolinyl pyrimidine derivatives) and suggests unexplored target space for the rational design of new NDH-2 inhibitors

Correlative Light, Electron Microscopy and Raman Spectroscopy Workflow To Detect and Observe Microplastic Interactions with Whole Jellyfish.

Many researchers have turned their attention to understanding microplastic interaction with marine fauna. Efforts are being made to monitor exposure pathways and concentrations and to assess the impact such interactions may have. To answer these questions, it is important to select appropriate experimental parameters and analytical protocols. This study focuses on medusae of Cassiopea andromeda jellyfish: a unique benthic jellyfish known to favor (sub-)tropical coastal regions which are potentially exposed to plastic waste from land-based sources. Juvenile medusae were exposed to fluorescent poly(ethylene terephthalate) and polypropylene microplastics (<300 μm), resin embedded, and sectioned before analysis with confocal laser scanning microscopy as well as transmission electron microscopy and Raman spectroscopy. Results show that the fluorescent microplastics were stable enough to be detected with the optimized analytical protocol presented and that their observed interaction with medusae occurs in a manner which is likely driven by the microplastic properties (e.g., density and hydrophobicity)

Relationships among common illness symptoms and the protective effect of breastfeeding in early childhood in MAL-ED: An eight-country cohort study

Children in low-income countries experience multiple illness symptoms in early childhood. Breastfeeding is protective against diarrhea and respiratory infections, and these illnesses are thought to be risk factors of one another, but these relationships have not been explored simultaneously. In the eight-site MAL-ED study, 1,731 infants were enrolled near birth and followed for 2 years. We collected symptoms and diet information through twice-weekly household visits. Poisson regression was used to determine if recent illness history was associated with incidence of diarrhea or acute lower respiratory infections (ALRI), accounting for exclusive breastfeeding. Recent diarrhea was associated with higher risk of incident diarrhea after the first 6 months of life (relative risk [RR] 1.10, 95% confidence interval [CI] 1.04, 1.16) and with higher risk of incident ALRI in the 3- to 5-month period (RR 1.23, 95% CI 1.03, 1.47). Fever was a consistent risk factor for both diarrhea and ALRI. Exclusive breastfeeding 0-6 months was protective against diarrhea (0-2 months: RR 0.39, 95% CI 0.32, 0.49; 3-5 months: RR 0.83, 95% CI 0.75, 0.93) and ALRI (3-5 months: RR 0.81, 95% CI 0.68, 0.98). Children with recent illness who were exclusively breastfed were half as likely as those not exclusively breastfed to experience diarrhea in the first 3 months of life. Recent illness was associated with greater risk of new illness, causing illnesses to cluster within children, indicating that specific illness-prevention programs may have benefits for preventing other childhood illnesses. The results also underscore the importance of exclusive breastfeeding in the first 6 months of life for disease prevention

Enteric dysfunction and other factors associated with attained size at 5 years : MAL-ED birth cohort study findings

Funding Information: The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project (MAL-ED) is carried out as a collaborative project supported by the Bill & Melinda Gates Foundation, the Foundation for the NIH, and the NIH/Fogarty International Center. This work was also supported by the Fogarty International Center, NIH (D43-TW009359 to ETR).Peer reviewe