Polymeric coatings are a promising option for the development of delivery systems for orally administered drugs. However, the gastrointestinal conditions to which they are subjected, which include ...low pH and solubility as well as peristaltic movements, can limit their applications. In this work, different formulations of polymeric coatings were produced using pH-sensitive materials consisting of copolymers of methyl acrylate, methyl methacrylate, and methacrylic acid. The polymers were synthesized by the emulsion polymerization technique, obtaining small average particle sizes (56–190 nm), molecular weights between 200,000 and 400,000 g/mol, and a glass transition temperature above 35 °C, which are suitable for film formation at room temperature. Thus, they were assessed as coatings for hydroxypropyl methylcellulose capsules (HPMC) using the immersion method, showing adequate capacity to protect the capsule at gastric pH (pH 1.2) and dissolve at the simulated intestinal pH (pH= 7.2). In particular, the higher the content of the acidic monomer, the higher the release time of the test molecule contained in the acrylic terpolymer-coated HPMC capsules proposed, which was a curcuminoid derivative due to their bright color and potential medical benefits. In addition, a minimum number of immersions was required for coating the HPMC capsules at high acidic concentrations, which further facilitates the delayed release needed for colonic treatment. However, too high proportions of methacrylic acid may result in cytotoxicity issues. Consequently, a biocompatible formulation containing a proportion of methyl acrylate, methyl methacrylate, and methacrylic acid of 7:3:3 is proposed as the most adequate for colonic release. Thus, by chemically modulating the molar percentages of the acrylic monomers, it was possible to obtain tailored acrylic terpolymer coatings with different characteristics and desired properties in order to modulate the release kinetics of an active substance in a colonic environment.
After all, still a magnificent impersonator Flores-Suárez, Luis F; Fernández-Sánchez, Mónica; Ahumada-Topete, Víctor H ...
Rheumatology (Oxford, England),
07/2021, Letnik:
60, Številka:
7
Journal Article
•Colombia is undergoing large socio-economic and political changes with unknown consequences for ecosystems and the services they provide.•We review the capacity of Colombia to monitor ecosystems and ...how they change over time. We found that many programs are already in place that go in this direction.•However, there is a large gap in terms of synthesis of existing information. Also, a system that consistently monitors ecosystem variables is urgently needed.•To increase Colombia's ability to respond to these transformations, we propose a set of actions to facilitate dialog, synthesis, and monitoring capacity.
After more than 50-years of armed conflict, Colombia is now transitioning to a more stable social and political climate due to a series of peace agreements between the government and different armed groups. Consequences of these socio-economic and political changes on ecosystems are largely uncertain, but there is growing concern about derived increases in environmental degradation. Here, we review the capacity of Colombia to monitor the state of its ecosystems and their rate of change over time. We found several important programs currently set in place by different institutions as well as by independent groups of scientists that address different aspects of environmental monitoring. However, most of the current initiatives could be improved in terms of data coverage, quality and access, and could be better articulated among each other. We propose a set of activities that would increase the capacity of Colombia to monitor its ecosystems, provide useful information to policy makers, and facilitate scientific research. These include: 1) the establishment of a national center for ecological synthesis that focuses on analyzing existing information; 2) the establishment of an ecological observatory system that collects new information, integrates remote sensing products, and produces near real-time products on key ecological variables; and 3) the creation of new platforms for dialog and action within existing scientific and policy groups.
Emission factors and personal exposure measurements were obtained in the working environment of a brick kiln yard in the municipality of Victoria de Durango, Mexico. Two kinds of kiln were evaluated; ...one was a fixed traditional kiln (FTK); the other was a local variation of an improved kiln called the ecological Marquez brick kiln (MK2). To distinguish it from the original design, we call it the Marquez kiln Durango (MKD). Ambient emission gases of carbon dioxide (CO
2
), carbon monoxide (CO), methane (CH
4
), and non-methane hydrocarbons (NMHC) were continuously followed using Fourier transform infrared spectrophotometry (FTIR). Elemental carbon (EC) and organic carbon (OC) ambient emissions were sampled on quartz filters and analyzed by chemical coulombimetry. Personal exposure to CO was continuously followed using portable monitors, and personal exposure to inhalable particles with diameters of generally 2.5 μm and smaller (PM
2.5
) was obtained using Teflon filters in portable particle samplers followed by gravimetric analysis. Results show that the FTK emits more PM
2.5
, EC, and OC per cooking stage than the MKD. In terms of PM
2.5
emission factors, relative to the FTK, the MK2 is 61% smaller and the MKD emission factor is 39% smaller. Against our expectations, the MKD showed higher work environment exposure levels. This is due to the untested changes to the original MK2 design and a mismanagement of the operation processes. Personal exposure to CO and PM
2.5
of local brick kiln workers was about three times higher than indoor exposure from the use of three-stone wood cookstoves in Mexico. The analysis of emission plumes from FTK and MKD using a coupled emission model dispersion model allowed us to evaluate the impacts, transport, and deposition area of the particle matter in the area surrounding Durango Brickyard (DB).
Understanding Earth system dynamics in light of ongoing human intervention and dependency remains a major scientific challenge. The unprecedented availability of data streams describing different ...facets of the Earth now offers fundamentally new avenues to address this quest. However, several practical hurdles, especially the lack of data interoperability, limit the joint potential of these data streams. Today, many initiatives within and beyond the Earth system sciences are exploring new approaches to overcome these hurdles and meet the growing interdisciplinary need for data-intensive research; using data cubes is one promising avenue. Here, we introduce the concept of Earth system data cubes and how to operate on them in a formal way. The idea is that treating multiple data dimensions, such as spatial, temporal, variable, frequency, and other grids alike, allows effective application of user-defined functions to co-interpret Earth observations and/or model–data integration. An implementation of this concept combines analysis-ready data cubes with a suitable analytic interface. In three case studies, we demonstrate how the concept and its implementation facilitate the execution of complex workflows for research across multiple variables, and spatial and temporal scales: (1) summary statistics for ecosystem and climate dynamics; (2) intrinsic dimensionality analysis on multiple timescales; and
(3) model–data integration. We discuss the emerging perspectives for investigating global interacting and coupled phenomena in observed or simulated data. In particular, we see many emerging perspectives of this approach for interpreting large-scale model ensembles. The latest developments in machine learning, causal inference, and model–data integration can be seamlessly implemented in the proposed framework, supporting rapid progress in data-intensive research across disciplinary boundaries.
There is a need for better classification and understanding of tumor-infiltrating lymphocytes (TILs). Here, we applied advanced functional genomics to interrogate 9,000 human tumors and multiple ...single-cell sequencing sets using benchmarked T cell states, comprehensive T cell differentiation trajectories, human and mouse vaccine responses, and other human TILs. Compared with other T cell states, enrichment of T memory/resident memory programs was observed across solid tumors. Trajectory analysis of single-cell melanoma CD8+ TILs also identified a high fraction of memory/resident memory-scoring TILs in anti-PD-1 responders, which expanded post therapy. In contrast, TILs scoring highly for early T cell activation, but not exhaustion, associated with non-response. Late/persistent, but not early activation signatures, prognosticate melanoma survival, and co-express with dendritic cell and IFN-γ response programs. These data identify an activation-like state associated to poor response and suggest successful memory conversion, above resuscitation of exhaustion, is an under-appreciated aspect of successful anti-tumoral immunity.
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•Improved global TIL classification methods are required to deconvolve cell states•αPD-1 non-responder TILs and dysfunctional TILs score for T activation, not exhaustion•αPD-1 response and patient survival associates with late T cell memory/TRM scoring•Persistent programs co-express with DC maturation and IFN-γ response programs
Jaiswal et al. highlight the need for improved tumor-infiltrating lymphocyte (TIL) classification by showing that current transcriptome assignments may misclassify early activated/effector TILs as exhausted. The study surveys 9,000 solid tumors, multiple single-cell RNA sequencing sets, mouse and human models, and scoring methods to reclassify TILs and associate melanoma survival to T cell memory/resident memory.
Dung invertebrate colonization and degradation levels of faeces from cattle treated with endectocides were studied. Faeces of control and doramectin (DRM) (subcutaneous) and moxidectin (MXD) ...(subcutaneous and topical) treated animals were deposited on the field from 3 to 21 days post-treatment (pt). Pats were recovered after 6 to 42 days post-deposition (pd). Faecal weight, dry matter, arthropods number, and drugs concentrations were determined. Total arthropods number was higher in control (
P<0.0001) than in the other groups from days 3 to 21 pt. Total number of insects recovered on days 3, 11, and 21 pt from control pats was significantly (
P<0.001) higher than in treated-animal pats during all the trial. At day 21 pt, the insects’ number in dung voided by DRM-treated cattle was (
P<0.05) lower than in the other groups. Comparisons of dung degradation among treatments were inconclusive. A lower adverse effect was observed for MXD compared with DRM. No significant degradation of MXD or DRM was observed during the present trial.
Atmospheric black carbon concentrations were measured at two urban sites (Mexico City and Monterrey), one suburban site (Juriquilla) and one high-altitude site (Altzomoni) in Mexico during 2015 and ...part of 2016. Black carbon concentrations were compared against other criteria gases finding a strong correlation with carbon monoxide at the urban sites. The carbon monoxide-black carbon correlation for the Mexico City site is 0.77. Urban sites had an average black carbon concentration of above 2.5 μg m−3, the suburban site 0.75 μg m−3, and the high-altitude site 0.27 μg m−3. Compared to other studies, the average levels are comparable, and the urban and suburban locations showed a trend towards increased atmospheric black carbon concentrations at year end. Other urban places (Guadalajara, Cuernavaca, and Iztapalapa) reported black carbon concentrations, but for less than a year. For the first time, a Latin-American country (Mexico) measured black carbon continuously at several sites for a year applying the same data quality assurance.
•Atmospheric black carbon is measured at two urban sites, one suburban site and one high-altitude site in Mexico during 2015.•Black carbon concentrations reported could become part of a baseline for future mitigation policies to reduce emissions.•Urban sites had average black carbon concentration above 2.5, the suburban site 0.75, and the high-altitude site 0.27 µg m-3.−3.•This is the first time that a Latin-American country measured black carbon continuously at several sites.
CARACTERIZACION ECOLOGICA DE HUMEDALES DE LA ZONA SEMIARIDA EN CHILE CENTRAL Figueroa, Ricardo(Universidad de Concepción Centro EULA-Chile Unidad de Sistemas Acuáticos); Suarez, María Luisa(Universidad de Murcia Departamento de Ecología e Hidrología); Andreu, Asunción(Universidad de Murcia Departamento de Zoología y Antropología Física) ...
Gayana,
2009, 20090001, Letnik:
73, Številka:
1
Journal Article
Odprti dostop
Uno de los ecosistemas naturales más amenazados del planeta son los humedales, que a pesar de su reconocida importancia, son poco valorados, lo que cobra mayor relevancia en Chile donde existen muy ...poca información sobre este tipo de ambientes. Este trabajo reúne antecedentes sobre tipología, hidrología, usos del suelo, unidades paisajísticas e impactos de 20 humedales de las regiones IV y V (Coquimbo y Valparaíso, Chile Central). El período de muestreo abarcó del 2 al 10 de julio de 2007 correspondiente a la fase húmeda del ciclo hidrológico anual. Se analizaron distintos parámetros físico-químicos: profundidad, ancho de lámina de agua, tipología del sustrato, temperatura del agua, pH y conductividad; y biológicos: vegetación acuática y de ribera, macroinvertebrados y fauna piscícola. Finalmente, para determinar el estado de conservación de estos humedales se aplicó el índice del Estado de Conservación de Ecosistemas Lénticos Someros (ECELS), propuesto por la Agencia Catalana del Agua. En general se trata de ecosistemas de tamaño medio, no superior a 50 has, aunque el Complejo del Yali (región V) supera las 500 ha. La mayoría son permanentes, con valor medio de pH de 7.84 (rango = 7.1 y 9.4) y conductividad de 11918,16 uS/cm, pero con un rango muy amplio (entre 665 y 52200 uS/cm), lo cual muestra el distinto origen de las aguas que mantienen estos humedales. En cuanto a la vegetación acuática Ceratophyllum chilensis, es el macrófito más habitual, pero siempre en humedales de baja conductividad. La comunidad de invertebrados acuáticos está compuesta por 42 taxa pertenecientes a 29 familias. Los insectos es el grupo más diversificado (17 familias) y de ellos, los dípteros con 8 familias. En cuanto a la fauna piscícola, se recolectaron cuatro especies: la lisa (Mugil cephalus) de origen marino, y tres exóticas: gambusia (Gambusia holbrooki), gambusia manchada (Cnesterodon decemmaculatus), y chanchito (Cichlasomafacetum). La aplicación del ECELS evaluó sólo dos humedales de máxima calidad, 5 la calidad fue buena, en 7 fue media y en 6 mala (5) o muy mala (1).
Wetlands are one of the most threatened natural ecosystems on the planet. In spite of their recognized importance, wetlands are not highly valued. This is particularly true in Chile, where little information is available regarding this type of environment. This paper presents data on the typology, hydrology, land uses, landscape units, and impact of 20 wetlands in regions IV (Coquimbo) and V (Valparaiso) of central Chile. Samples were taken from 2 to 10 July 2007, during the wet phase of the annual hydrological cycle. We analyzed a variety of physical-chemical (depth, width of the water surface, substrate typology, temperature, pH, water conductivity) and biological parameters (aquatic and shoreline vegetation, macroinvertebrates, ichthyic fauna). We used the Index of the State of Conservation of Shallow Lentic Ecosystems (ECELS), proposed by the Catalan Water Agency, to determine the state of conservation of these wetlands. In general, this index deals with mid-sized ecosystems that do not exceed 50 ha although, herein, the Yali complex (Region V) is an exception (>500 ha). Most of these systems are permanent and average 7,84 in pH (range = 7,1-9,4) and 11918,2 uS/cm in conductivity (range = 665-52200 uS/cm). The very wide range showed different origins of the waters that sustain these wetlands. As for the aquatic vegetation, Ceratophyllum chilensis is the most common macrophyte in low-conductivity wetlands. The aquatic invertebrate community is composed of 42 taxa belonging to 29 families. Insects constitute the most diverse group (17 families), particularly the dipterans (8 families). Four fish species were collected during sampling. One, flathead mullet or lisa (Mugil cephalus), has marine origins and the other three are exotic species: mosquito fish or gambusia (Gambusia holbrooki), ten spotted live-bearer (Cnesterodon decemmaculatus), and chameleon cichlid (Cichlasomafacetum). According to the ECELS, the quality of these wetlands is maximum in only two cases, good in five, regular in seven, poor in another five cases, and very poor in one case.
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