Palygorskite is a natural fibrous clay mineral that can be used in several applications, for which colloidal stability in aqueous suspensions is a key point to improve its performance. In this study, ...methods of magnetic stirring, high-speed shearing, and ultrasonication, as well as different chemical dispersants, combined with these methods, namely carboxymethylcellulose, alginate, polyphosphate, and polyacrylate, were used to improve the dispersibility and the formation of stable suspensions of palygorskite in different conditions of pH. The stability and particle size of suspensions with a low concentration of palygorskite were evaluated by visual inspection, optical and electron microscopy, dynamic light scattering, and zeta potential measurements. Moreover, the palygorskite used in this work was initially characterized for its mineralogical, chemical, physical, and morphological properties. It was found that more stable suspensions were produced with ultrasonication compared to the other two physical treatments, with magnetic stirring being inefficient in all tested cases, and for higher pH values (pH of 12 and pH of 8, the natural pH of the clay) when compared to lower pH values (pH of 3). Remarkably, combined with ultrasonication, carboxymethylcellulose or in a lesser extent polyphosphate at near neutral pH allowed for the disaggregation of crystal bundles of palygorskite into individualized crystals. These results may be helpful to optimize the performance of palygorskite in several domains where it is applied.
The dispersion state and the efficiency of the mixture of the different components in a composite film have an important impact on its mechanical and optical properties. In the present work, the ...impacts of different dispersion treatments on the disaggregation state of fibrous clay particles in water, and on the properties of related cellulose nanofiber (CNF)-based composite films, were evaluated. X-ray diffraction studies, performed on samples of sepiolite and palygorskite, revealed only minor changes in the diffraction pattern when the minerals were subjected to ultrasonic treatment, with or without the addition of different chemical dispersing agents. Conversely, microscopic studies revealed important differences in the dispersion state of the samples, induced by the addition of the different dispersants, showing an improvement in the disaggregation of the mineral crystals. The composite films prepared with sepiolite (and carboxymethylcellulose, as chemical dispersant) dispersed using ultrasonic treatment, and different types of CNF, showed improved optical and mechanical properties when compared with composites of the same counterparts prepared with sepiolite dispersed using a high-speed shear disperser.
•Disaggregation state of minerals has great impact on the composite properties.•Use of dispersants combined with ultrasound induced superior disaggregation of the minerals.•Polyphosphate and bio-based carboxymethylcellulose were the most effective.•Minor changes in the diffraction pattern of the minerals were observed.•Highly transparent and robust composite films resulted from well-dispersed mineral samples.
Waterborne diseases can have different origins, micro-organisms such as bacteria and parasites being the most important ones. In this study, two recreational aquatic environments were studied in the ...province of Salta, Argentina. Water samples collected from three different locations, two from a creek and one from the outlet of a thermal complex, were monitored at four time points. Physicochemical and microbiological characterization of each point was conducted, as well as a search for parasites and amebae. Parasites were identified through optical microscopy observations and free-living amebae (FLA) were isolated by spiking in Petri dishes followed by subsequent molecular identification. Water samples from the outlet of the thermal complex showed different physicochemical characteristics from those of the creek. Bacterial indicators of contamination were detected at all points; however, the creek water had a significantly higher concentration of Pseudomonas sp. Sporadically, creek samples exhibited Ascaris spp. eggs, Giardia sp. cysts, and ancylostomid eggs. The presence of FLA was observed in all samples, 15 of which were isolated and identified as Acanthamoeba sp., mostly belonging to the T4 genotype. Parasite surveillance in recreational aquatic environments is an important complement to traditional microbial indicators for assessing water quality. The identified parasites represent a potential health risk for people using these environments.Waterborne diseases can have different origins, micro-organisms such as bacteria and parasites being the most important ones. In this study, two recreational aquatic environments were studied in the province of Salta, Argentina. Water samples collected from three different locations, two from a creek and one from the outlet of a thermal complex, were monitored at four time points. Physicochemical and microbiological characterization of each point was conducted, as well as a search for parasites and amebae. Parasites were identified through optical microscopy observations and free-living amebae (FLA) were isolated by spiking in Petri dishes followed by subsequent molecular identification. Water samples from the outlet of the thermal complex showed different physicochemical characteristics from those of the creek. Bacterial indicators of contamination were detected at all points; however, the creek water had a significantly higher concentration of Pseudomonas sp. Sporadically, creek samples exhibited Ascaris spp. eggs, Giardia sp. cysts, and ancylostomid eggs. The presence of FLA was observed in all samples, 15 of which were isolated and identified as Acanthamoeba sp., mostly belonging to the T4 genotype. Parasite surveillance in recreational aquatic environments is an important complement to traditional microbial indicators for assessing water quality. The identified parasites represent a potential health risk for people using these environments.
•Se evaluó la calidad de aguas de uso recreativo en la provincia de Salta.•Los parámetros microbiológicos en su mayoría superan los límites para la recreación.•Se detectaron formas parasitarias con ...gran implicancia para la salud pública.•Se identificaron por PCR amebas de vida libre del género Acanthamoeba.•La caracterización parasitológica es necesaria en controles de calidad rutinarios.
Las enfermedades transmitidas por el agua pueden tener diferente origen; las bacterias y los parásitos son los agentes causales más importantes. En este trabajo se monitorearon muestras de agua en tres puntos próximos a una zona recreativa en la provincia de Salta (Argentina): dos en un arroyo que rodea a un complejo termal, aguas arriba y aguas abajo de donde descargan las aguas de dicho complejo; el tercero, en la zona de salida del agua proveniente del complejo. Las muestras se tomaron en cuatro meses del año. Se realizó la caracterización fisicoquímica, bacteriológica y búsqueda de parásitos y amebas de vida libre (AVL) del agua en cada punto. Las muestras de agua a la salida del complejo termal presentaron características fisicoquímicas diferentes a las del arroyo. En todos los puntos se detectaron indicadores bacterianos de contaminación, pero el agua del arroyo tuvo una concentración significativamente mayor de Pseudomonas sp. En las muestras del arroyo se encontraron, esporádicamente, huevos de Ascaris spp., quistes de Giardia sp. y huevos de ancilostomideos. En todas las muestras se encontraron AVL; se aislaron 15AVL, que se identificaron como Acanthamoeba sp., mayoritariamente pertenecientes al genotipo T4. La vigilancia de parásitos en ambientes acuáticos de uso recreativo es un complemento importante a la de los indicadores microbiológicos tradicionales para la evaluación de la calidad del agua. Los parásitos identificados representan un potencial riesgo para la salud de las personas que hacen uso de dichos ambientes.
Waterborne diseases can have different origins, micro-organisms such as bacteria and parasites being the most important ones. In this study, two recreational aquatic environments were studied in the province of Salta, Argentina. Water samples collected from three different locations, two from a creek and one from the outlet of a thermal complex, were monitored at four time points. Physicochemical and microbiological characterization of each point was conducted, as well as a search for parasites and amebae. Parasites were identified through optical microscopy observations and free-living amebae (FLA) were isolated by spiking in Petri dishes followed by subsequent molecular identification. Water samples from the outlet of the thermal complex showed different physicochemical characteristics from those of the creek. Bacterial indicators of contamination were detected at all points; however, the creek water had a significantly higher concentration of Pseudomonas sp. Sporadically, creek samples exhibited Ascaris spp. eggs, Giardia sp. cysts, and ancylostomid eggs. The presence of FLA was observed in all samples, 15 of which were isolated and identified as Acanthamoeba sp., mostly belonging to the T4 genotype. Parasite surveillance in recreational aquatic environments is an important complement to traditional microbial indicators for assessing water quality. The identified parasites represent a potential health risk for people using these environments.
Diffuse midline glioma (DMG), including tumors diagnosed in the brainstem (diffuse intrinsic pontine glioma; DIPG), are uniformly fatal brain tumors that lack effective treatment. Analysis of ...CRISPR/Cas9 loss-of-function gene deletion screens identified PIK3CA and MTOR as targetable molecular dependencies across patient derived models of DIPG, highlighting the therapeutic potential of the blood-brain barrier-penetrant PI3K/Akt/mTOR inhibitor, paxalisib. At the human-equivalent maximum tolerated dose, mice treated with paxalisib experienced systemic glucose feedback and increased insulin levels commensurate with patients using PI3K inhibitors. To exploit genetic dependence and overcome resistance while maintaining compliance and therapeutic benefit, we combined paxalisib with the antihyperglycemic drug metformin. Metformin restored glucose homeostasis and decreased phosphorylation of the insulin receptor in vivo, a common mechanism of PI3K-inhibitor resistance, extending survival of orthotopic models. DIPG models treated with paxalisib increased calcium-activated PKC signaling. The brain penetrant PKC inhibitor enzastaurin, in combination with paxalisib, synergistically extended the survival of multiple orthotopic patient-derived and immunocompetent syngeneic allograft models; benefits potentiated in combination with metformin and standard-of-care radiotherapy. Therapeutic adaptation was assessed using spatial transcriptomics and ATAC-Seq, identifying changes in myelination and tumor immune microenvironment crosstalk. Collectively, this study has identified what we believe to be a clinically relevant DIPG therapeutic combinational strategy.
Waterborne diseases can have different origins, micro-organisms such as bacteria and parasites being the most important ones. In this study, two recreational aquatic environments were studied in the ...province of Salta, Argentina. Water samples collected from three different locations, two from a creek and one from the outlet of a thermal complex, were monitored at four time points. Physicochemical and microbiological characterization of each point was conducted, as well as a search for parasites and amebae. Parasites were identified through optical microscopy observations and free-living amebae (FLA) were isolated by spiking in Petri dishes followed by subsequent molecular identification. Water samples from the outlet of the thermal complex showed different physicochemical characteristics from those of the creek. Bacterial indicators of contamination were detected at all points; however, the creek water had a significantly higher concentration of Pseudomonas sp. Sporadically, creek samples exhibited Ascaris spp. eggs, Giardia sp. cysts, and ancylostomid eggs. The presence of FLA was observed in all samples, 15 of which were isolated and identified as Acanthamoeba sp., mostly belonging to the T4 genotype. Parasite surveillance in recreational aquatic environments is an important complement to traditional microbial indicators for assessing water quality. The identified parasites represent a potential health risk for people using these environments.
Purpose: To show the functional, clinical, and biological significance of c-Jun-NH 2 -kinase (JNK)-1 in ovarian carcinoma.
Experimental Design: Analysis of the impact of JNK on 116 epithelial ovarian ...cancers was conducted. The role of JNK in vitro and in experimental models of ovarian cancer was assessed. We studied the role of N -5-4-(4-methyl piperazine methyl)-benzoylamido-2-methylphenyl-4-3-(4-methyl)-pyridyl-2-pyrimidine amine (WBZ_4), a novel
JNK inhibitor redesigned from imatinib based on targeting wrapping defects, in cell lines and in experimental models of ovarian
cancer.
Results: We found a significant association of pJNK with progression-free survival in the 116 epithelial ovarian cancers obtained
at primary debulking therapy. WBZ_4 led to cell growth inhibition and increased apoptosis in a dose-dependent fashion in four
ovarian cancer cell lines. In vivo , whereas imatinib had no effect on tumor growth, WBZ_4 inhibited tumor growth in orthotopic murine models of ovarian cancer.
The antitumor effect was further increased in combination with docetaxel. Silencing of JNK-1 with systemically administered
siRNA led to significantly reduced tumor weights compared with nonsilencing siRNA controls, indicating that indeed the antitumor
effects observed were due to JNK-1 inhibition.
Conclusions: These studies identify JNK-1 as an attractive therapeutic target in ovarian carcinoma and that the redesigned WBZ_4 compound
should be considered for further clinical development. Clin Cancer Res; 16(1); 184–94
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