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1.
PLoS Negl Trop Dis ; 17(2): e0011063, 2023 02.
Article in English | MEDLINE | ID: mdl-36821543

ABSTRACT

Caterpillars of the Neotropical genus Lonomia (Lepidoptera: Saturniidae) are responsible for some fatal envenomation of humans in South America inducing hemostatic disturbances in patients upon skin contact with the caterpillars' spines. Currently, only two species have been reported to cause hemorrhagic syndromes in humans: Lonomia achelous and Lonomia obliqua. However, species identifications have remained largely unchallenged despite improved knowledge of venom diversity and growing evidence that the taxonomy used over past decades misrepresents and underestimates species diversity. Here, we revisit the taxonomic diversity and distribution of Lonomia species using the most extensive dataset assembled to date, combining DNA barcodes, morphological comparisons, and geographical information. Considering new evidence for seven undescribed species as well as three newly proposed nomenclatural changes, our integrative approach leads to the recognition of 60 species, of which seven are known or strongly suspected to cause severe envenomation in humans. From a newly compiled synthesis of epidemiological data, we also examine the consequences of our results for understanding Lonomia envenomation risks and call for further investigations of other species' venom activities. This is required and necessary to improve alertness in areas at risk, and to define adequate treatment strategies for envenomed patients, including performing species identification and assessing the efficacy of anti-Lonomia serums against a broader diversity of species.


Subject(s)
Arthropod Venoms , Moths , Animals , Humans , Larva , Arthropod Venoms/toxicity , Hemorrhage , South America
2.
Nat Commun ; 10(1): 2720, 2019 06 20.
Article in English | MEDLINE | ID: mdl-31221973

ABSTRACT

Public Health Laboratories (PHLs) in Puerto Rico did not escape the devastation caused by Hurricane Maria. We implemented a quality management system (QMS) approach to systematically reestablish laboratory testing, after evaluating structural and functional damage. PHLs were inoperable immediately after the storm. Our QMS-based approach began in October 2017, ended in May 2018, and resulted in the reestablishment of 92% of baseline laboratory testing capacity. Here, we share lessons learned from the historic recovery of the largest United States' jurisdiction to lose its PHL capacity, and provide broadly applicable tools for other jurisdictions to enhance preparedness for public health emergencies.

3.
Article in English | MEDLINE | ID: mdl-31082684

ABSTRACT

Sulfur and nitrogen mustards are internationally banned vesicants listed as Schedule 1 chemical agents in the Chemical Weapons Convention. These compounds are highly reactive electrophiles that form stable adducts to a variety of available amino acid residues on proteins upon exposure. We present a quantitative exposure assay that simultaneously measures agent specific protein adducts to cysteine for sulfur mustard (HD) and three nitrogen mustards (HN1, HN2, and HN3). Proteinase K was added to a serum or plasma sample to digest protein adducts and form the target analyte, the blister agent bound to the tripeptide cysteine-proline-phenylalanine (CPF). The mustard adducted-tripeptide was purified by solid phase extraction and analyzed using isotope dilution LC-MS/MS. Product ion structures were identified using high-resolution product ion scan data for HD-CPF, HN1-CPF, HN2-CPF, and HN3-CPF. Thorough matrix comparison, analyte recovery, ruggedness, and stability studies were incorporated during method validation to produce a robust method. The method demonstrated long term-stability, precision (RSD < 15%), and intra- and inter-day accuracies > 85% across the reportable range of 3.00-200 ng/mL for each analyte. Compared to previously published assays, this method quantitates both sulfur and nitrogen mustard exposure biomarkers, requires only 10 µL of sample volume, and can use either a liquid sample or dried sample spot.


Subject(s)
Environmental Exposure/analysis , Mustard Compounds/blood , Serum Albumin/chemistry , Biomarkers/blood , Biomarkers/chemistry , Chromatography, High Pressure Liquid , Cysteine/blood , Cysteine/chemistry , Humans , Mustard Compounds/chemistry , Reproducibility of Results , Serum Albumin/analysis , Tandem Mass Spectrometry
4.
Molecules ; 24(6)2019 Mar 21.
Article in English | MEDLINE | ID: mdl-30901824

ABSTRACT

Zinc porphyrin-functionalized fullerene [C60] derivatives have been synthesized and used to prepare titania-based composites. The electrochemical properties and HOMO and LUMO levels of the photosensitizers were determined by electrochemical measurements. Raman and IR techniques were used to study chemical groups present on the titania surface. Absorption properties of the composites were measured in the solid state by diffuse reflectance UV-Vis spectra (DRS). The zeta potential and aggregate sizes were determined using dynamic light scattering (DLS) and electrophoretic light scattering (ELS) techniques. Surface areas were estimated based on Brunauer⁻Emmett⁻Teller (BET) isotherms. The photocatalytic activity of the photocatalysts was tested using two model pollutants, phenol and methylene blue. The composite with the highest photocatalytic potential (1/TiO2) was used for river and wastewater remediation. The photodegradation intermediates were identified by LC-UV/Vis-MS/MS techniques.


Subject(s)
Fullerenes , Light , Metalloporphyrins , Titanium , Catalysis , Environmental Restoration and Remediation , Fresh Water , Fullerenes/chemistry , Metalloporphyrins/chemistry , Photochemical Processes , Reproducibility of Results , Rivers , Spectroscopy, Fourier Transform Infrared , Titanium/chemistry , Wastewater , Water Pollutants, Chemical/chemistry
5.
Chemistry ; 20(35): 11111-9, 2014 Aug 25.
Article in English | MEDLINE | ID: mdl-25078652

ABSTRACT

A new donor-acceptor system, in which the electron donor triphenylamine (TPA) and the electron acceptor C60 are bridged through a cis- or trans-platinum(II) acetylide spacer have been prepared. Ground-state studies were conducted using electrochemistry and UV/Vis spectroscopy. Fluorescence studies suggested that charge transfer is the deactivation mechanism for the singlet excited state, and this was verified by transient absorption spectroscopy. Selective photoexcitation of 1 and 2 at 387 nm leads to a fast charge transfer between the TPA and C60, which gives rise to a radical ion-pair state (TPA(·+)-Pt-C60(·-)). Our results suggest that charge transfer is favored for the cis configuration while the presence of the trans configuration in the Pt(II) diacetylide results in a longer-lived charge separated states.

6.
ACS Appl Mater Interfaces ; 6(5): 3712-20, 2014 Mar 12.
Article in English | MEDLINE | ID: mdl-24524362

ABSTRACT

C60-Triphenylamine dyads were synthesized for incorporation as photoswitched interfacial layers in organic photovoltaic (OPV) cells. Self-assembled monolayers (SAMs) of these dyads on gold (through S-Au and C60-Au interactions) were prepared through one or two adsorption processes, and their packing densities were fully characterized. Analysis using quartz crystal microbalance (QCM) and electrochemical impedance spectroscopy (EIS) measurements indicated that all SAMs exhibit dense coverage on the gold surfaces. Electrochemical desorption in KOH confirmed that the cis-1 dyad is anchored to the gold surface through its thiol group. Impedance measurements in the absence and presence of UV irradiation were performed to observe the photoswitched properties of these surface confined dyads. Upon UV light exposure of the SAMs, the charge-transfer resistance decreased when Fe(CN)6(3-/4-) was used as the probe redox couple and increased with Ru(NH3)6(3+/2+), confirming the generation of positive charges on the surface upon UV irradiation.

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