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1.
MMWR Morb Mortal Wkly Rep ; 73(37): 825-827, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39298367

RESUMEN

In 2020, during the COVID-19 pandemic, CDC established the National Wastewater Surveillance System and later expanded it to include mpox and influenza A data dashboards.† Wastewater utility partners have cited community health benefits as a motivating factor for participating in wastewater surveillance; a lack of public support for wastewater surveillance activities might lead utility partners to cease participation (1,2). However, little is known about public support for wastewater monitoring and its influence on protective health behaviors. As innovative surveillance strategies such as wastewater surveillance evolve, ethical considerations, including understanding public perceptions regarding support for these activities and potential risks to communities, are essential (3).


Asunto(s)
Intención , Aguas Residuales , Humanos , Estados Unidos/epidemiología , Adulto , Masculino , Femenino , Persona de Mediana Edad , COVID-19/prevención & control , COVID-19/epidemiología , Adulto Joven , Conductas Relacionadas con la Salud , Anciano , Monitoreo del Ambiente , Adolescente
2.
iScience ; 27(6): 109958, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38840843

RESUMEN

Biochar obtained via microwave-assisted pyrolysis (MAP) at 720 W and 15 min from cocoa pod husk (CPH) is an efficient adsorbent of Cd2+(aq). Biochar of residual biomass of CPH (BCCPH) possesses favorable physicochemical and morphological properties, featuring a modest surface area yet a suitable porous structure. Adsorption, predominantly governed by physisorption, is influenced by the oxygen-containing active sites (-COOR, -C(R)O, and -CH2OR; R = H, alkyl). CdCO3 formation occurs during adsorption. Experimental data were well-fitted into various kinetic models for a broad understanding of the sorption process. Langmuir model indicates a maximum adsorption capacity of 14.694 mg/g. The thermodynamic study confirms the spontaneous and endothermic sorption. Studies at the molecular level have revealed that the Cd2+ ion tends to bind to surface aromatic carbon atoms. This sustainable approach produces BCCPH via MAP as a solution for waste transformation into water-cleaning materials.

3.
Environ Sci Technol ; 57(18): 7240-7253, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37099683

RESUMEN

Ammonia monooxygenase and analogous oxygenase enzymes contribute to pharmaceutical biotransformation in activated sludge. In this study, we hypothesized that methane monooxygenase can enhance pharmaceutical biotransformation within the benthic, diffuse periphytic sediments (i.e., "biomat") of a shallow, open-water constructed wetland. To test this hypothesis, we combined field-scale metatranscriptomics, porewater geochemistry, and methane gas fluxes to inform microcosms targeting methane monooxygenase activity and its potential role in pharmaceutical biotransformation. In the field, sulfamethoxazole concentrations decreased within surficial biomat layers where genes encoding for the particulate methane monooxygenase (pMMO) were transcribed by a novel methanotroph classified as Methylotetracoccus. Inhibition microcosms provided independent confirmation that methane oxidation was mediated by the pMMO. In these same incubations, sulfamethoxazole biotransformation was stimulated proportional to aerobic methane-oxidizing activity and exhibited negligible removal in the absence of methane, in the presence of methane and pMMO inhibitors, and under anoxia. Nitrate reduction was similarly enhanced under aerobic methane-oxidizing conditions with rates several times faster than for canonical denitrification. Collectively, our results provide convergent in situ and laboratory evidence that methane-oxidizing activity can enhance sulfamethoxazole biotransformation, with possible implications for the combined removal of nitrogen and trace organic contaminants in wetland sediments.


Asunto(s)
Metano , Humedales , Oxidación-Reducción , Minerales , Biotransformación
4.
MethodsX ; 10: 102074, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36865651

RESUMEN

Shallow, unit process open water wetlands harbor a benthic microbial mat capable of removing nutrients, pathogens, and pharmaceuticals at rates that rival or exceed those of more traditional systems. A deeper understanding of the treatment capabilities of this non-vegetated, nature-based system is currently hampered by experimentation limited to demonstration-scale field systems and static lab-based microcosms that integrate field-derived materials. This limits fundamental mechanistic knowledge, extrapolation to contaminants and concentrations not present at current field sites, operational optimization, and integration into holistic water treatment trains. Hence, we have developed stable, scalable, and tunable laboratory reactor analogs that offer the capability to manipulate variables such as influent rates, aqueous geochemistry, light duration, and light intensity gradations within a controlled laboratory environment. The design is composed of an experimentally adaptable set of parallel flow-through reactors and controls that can contain field-harvested photosynthetic microbial mats ("biomat") and could be adapted for analogous photosynthetically active sediments or microbial mats. The reactor system is contained within a framed laboratory cart that integrates programable LED photosynthetic spectrum lights. Peristaltic pumps are used to introduce specified growth media, environmentally derived, or synthetic waters at a constant rate, while a gravity-fed drain on the opposite end allows steady-state or temporally variable effluent to be monitored, collected, and analyzed. The design allows for dynamic customization based on experimental needs without confounding environmental pressures and can be easily adapted to study analogous aquatic, photosynthetically driven systems, particularly where biological processes are contained within benthos. The diel cycles of pH and dissolved oxygen (DO) are used as geochemical benchmarks for the interplay of photosynthetic and heterotrophic respiration and likeness to field systems. Unlike static microcosms, this flow-through system remains viable (based on pH and DO fluctuations) and has at present been maintained for more than a year with original field-based materials.•Lab-scale flow-through reactors enable controlled and accessible exploration of shallow, open water constructed wetland function and applications.•The footprint and operating parameters minimize resources and hazardous waste while allowing for hypothesis-driven experiments.•A parallel negative control reactor quantifies and minimizes experimental artifacts.

5.
Environ Sci Technol ; 56(20): 14462-14477, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36197061

RESUMEN

In shallow, open-water engineered wetlands, design parameters select for a photosynthetic microbial biomat capable of robust pharmaceutical biotransformation, yet the contributions of specific microbial processes remain unclear. Here, we combined genome-resolved metatranscriptomics and oxygen profiling of a field-scale biomat to inform laboratory inhibition microcosms amended with a suite of pharmaceuticals. Our analyses revealed a dynamic surficial layer harboring oxic-anoxic cycling and simultaneous photosynthetic, nitrifying, and denitrifying microbial transcription spanning nine bacterial phyla, with unbinned eukaryotic scaffolds suggesting a dominance of diatoms. In the laboratory, photosynthesis, nitrification, and denitrification were broadly decoupled by incubating oxic and anoxic microcosms in the presence and absence of light and nitrogen cycling enzyme inhibitors. Through combining microcosm inhibition data with field-scale metagenomics, we inferred microbial clades responsible for biotransformation associated with membrane-bound nitrate reductase activity (emtricitabine, trimethoprim, and atenolol), nitrous oxide reduction (trimethoprim), ammonium oxidation (trimethoprim and emtricitabine), and photosynthesis (metoprolol). Monitoring of transformation products of atenolol and emtricitabine confirmed that inhibition was specific to biotransformation and highlighted the value of oscillating redox environments for the further transformation of atenolol acid. Our findings shed light on microbial processes contributing to pharmaceutical biotransformation in open-water wetlands with implications for similar nature-based treatment systems.


Asunto(s)
Compuestos de Amonio , Humedales , Atenolol , Biotransformación , Desnitrificación , Emtricitabina/metabolismo , Metoprolol , Nitrato Reductasas/metabolismo , Nitrificación , Nitrógeno/metabolismo , Óxido Nitroso , Oxígeno , Preparaciones Farmacéuticas , Fotosíntesis , Trimetoprim , Agua
6.
Adv Sci (Weinh) ; 8(24): e2103023, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34716694

RESUMEN

Short peptides reflecting major histocompatibility complex (MHC) class I (MHC-I) epitopes frequently lack sufficient immunogenicity to induce robust antigen (Ag)-specific CD8+ T cell responses. In the current work, it is demonstrated that position-scanning peptide libraries themselves can serve as improved immunogens, inducing Ag-specific CD8+ T cells with greater frequency and function than the wild-type epitope. The approach involves displaying the entire position-scanning library onto immunogenic nanoliposomes. Each library contains the MHC-I epitope with a single randomized position. When a recently identified MHC-I epitope in the glycoprotein gp70 envelope protein of murine leukemia virus (MuLV) is assessed, only one of the eight positional libraries tested, randomized at amino acid position 5 (Pos5), shows enhanced induction of Ag-specific CD8+ T cells. A second MHC-I epitope from gp70 is assessed in the same manner and shows, in contrast, multiple positional libraries (Pos1, Pos3, Pos5, and Pos8) as well as the library mixture give rise to enhanced CD8+ T cell responses. The library mixture Pos1-3-5-8 induces a more diverse epitope-specific T-cell repertoire with superior antitumor efficacy compared to an established single mutation mimotope (AH1-A5). These data show that positional peptide libraries can serve as immunogens for improving CD8+ T-cell responses against endogenously expressed MHC-I epitopes.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Leucemia/inmunología , Activación de Linfocitos/inmunología , Biblioteca de Péptidos , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos BALB C
7.
Phys Chem Chem Phys ; 22(34): 19089-19099, 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32807995

RESUMEN

The electron density profile of bilayers of DPPC/cholesterol mixtures supported on semiconductor grade silicon substrates were studied with the objective of determining how the proximity of a solid interface modifies the phase diagram of mixed bilayers. The bilayers were studied in situ immersed in water via synchrotron X-ray reflectivity (XRR). Measurements were performed as a function of temperature through the main phase transition and cholesterol mole fractions up to 40%. Analysis of XRR yields the bilayer thickness, roughness and leaflet asymmetry. We find that the structure of the pure DPPC bilayers in the gel phase is in agreement with previous X-ray measurements of supported bilayers deposited via vesicle fusion and multilamellar vesicles but show more clearly defined features than measurements made on films formed using Langmuir-Blodget Langmuir-Shaffer (LB) deposition. Examination of bilayer thickness vs. temperature shows that the melting temperature for supported bilayers is shifted upwards by approximately 4 °C relative to multilamellar vesicles and that the melting temperature decreases with increasing cholesterol content up to 20%. For pure DPPC bilayers the leaflets melt in two stages with the distal leaflet melting first. For cholesterol concentrations of 10% and 20% there is no clear indication of separate melting. For 33% and 40% cholesterol content no clear transition is seen in the bilayer thickness, but an abrupt change in roughness indicates possible microdomain formation in the 40% cholesterol sample.


Asunto(s)
1,2-Dipalmitoilfosfatidilcolina/química , Colesterol/química , Membrana Dobles de Lípidos/química , Estructura Molecular , Sincrotrones , Temperatura de Transición , Agua/química , Rayos X
8.
BMC Anesthesiol ; 20(1): 46, 2020 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-32093637

RESUMEN

BACKGROUND: This quality improvement (QI) project was performed at a single center to determine the incidence of postoperative complications associated with use of cuffed airway devices. An educational program was then completed that involved training our anesthesia providers about complications related to excessive cuff pressure and how to utilize a quantitative cuff pressure measurement device (manometer). The impact of this educational initiative was assessed by comparing the incidence of postoperative complications associated with the use of airway devices before and after the training period. METHODS: After approval by our institution's Institutional Review Board, a pre-intervention (baseline) survey was obtained from 259 adult patients after having undergone surgery with general anesthesia with the use of an endotracheal tube (ETT) or laryngeal mask airway (LMA). Survey responses were used to determine the baseline incidence of sore throat, hoarseness, and dysphagia. Once these results were obtained, education was provided to the anesthesia department members addressing the complications associated with excessive cuff pressures, appropriate cuff pressures based on manufacturer recommendations, and instructions on the use of a quantitative monitor to determine cuff pressure (manometry). Clinical care was then changed by requiring intraoperative cuff pressure monitoring throughout our institution for all surgical patients. After this educational period, 299 patients completed the same survey describing postoperative airway complications. RESULTS: The use of manometry reduced the incidence of moderate-to-severe postoperative sore throat in the pre- vs. post-intervention groups (35 patients vs 31 patients, p = 0.045), moderate to severe hoarseness (30 patients vs 13, patients p = 0.0001), and moderate-to-severe dysphagia (13 patients vs 5 patients, p = 0.03). CONCLUSION: Caring for patients in the perioperative setting frequently entails placement of an airway device. This procedure is associated with several potential complications, including sore throat, coughing, and vocal cord damage. Our quality improvement initiative has shown that intraoperative management of intra-cuff pressure based on manometry is feasible to implement in clinical practice and can reduce postoperative airway complications.


Asunto(s)
Cuidados Intraoperatorios/métodos , Intubación Intratraqueal/efectos adversos , Máscaras Laríngeas/efectos adversos , Manometría/métodos , Complicaciones Posoperatorias/prevención & control , Mejoramiento de la Calidad , Competencia Clínica , Trastornos de Deglución/prevención & control , Diseño de Equipo , Ronquera/prevención & control , Humanos , Incidencia , Cuidados Intraoperatorios/educación , Faringitis/prevención & control , Presión
10.
Phys Rev E ; 97(2-1): 020601, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29548072

RESUMEN

The dynamics of concentrated suspensions of the eye-lens protein alpha crystallin have been measured using x-ray photon correlation spectroscopy. Measurements were made at wave vectors corresponding to the first peak in the hard-sphere structure factor and volume fractions close to the critical volume fraction for the glass transition. Langevin dynamics simulations were also performed in parallel to the experiments. The intermediate scattering function f(q,τ) could be fit using a stretched exponential decay for both experiments and numerical simulations. The measured relaxation times show good agreement with simulations for polydisperse hard-sphere colloids.

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