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1.
ACS Appl Mater Interfaces ; 16(37): 49186-49196, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39252609

RESUMEN

Achieving timely and effective hemorrhage control is imperative for the survival of individuals with severe bleeding. Hemostatic materials, by enhancing the natural cell-based coagulation response, are essential tools in modern and military medical practice for controlling bleeding, especially in emergency and surgical settings. Here, we report a new type of composite hemostatic material with two different aluminosilicate-based components, kaolin and zeolite, which synergistically work together in different stages of the coagulation cascade reactions. Kaolin can effectively activate the clotting factor FXII in the early stage, and zeolite can accumulate and assemble FXa and FVa on its surface and thereafter lead to the formation of highly active thrombin in the later stage. The synergistic action mechanism between kaolin and zeolite significantly boosts the levels of FXIIa and FXa, and it also greatly enhances plateau thrombin activity. For practical application, a kaolin-modified zeolite gauze is fabricated, and it demonstrates excellent hemostatic effectiveness. Compared to the combat gauze currently used in front-line treatment, it reduces blood loss by 75% and shortens hemostasis time by 33% in a rabbit femoral artery injury model. In addition, this kaolin-zeolite gauze has no heat release problem and a nearly zero particle shedding rate, which greatly decreases the safety risk compared to current commercial inorganic-based hemostatic gauzes.


Asunto(s)
Hemorragia , Hemostáticos , Caolín , Zeolitas , Caolín/química , Caolín/farmacología , Zeolitas/química , Zeolitas/farmacología , Animales , Conejos , Hemorragia/tratamiento farmacológico , Hemostáticos/química , Hemostáticos/farmacología , Coagulación Sanguínea/efectos de los fármacos , Trombina/química , Humanos
2.
Int J Biol Macromol ; 278(Pt 1): 134596, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39127291

RESUMEN

In this work, chitosan was combined with bio-vanillin (BV) and kaolin clay (KC) to create a novel antifungal and biodegradable food packaging film. The chitosan/KC/BV film exhibited an antioxidant capacity of 80 % as measured by DPPH assay, which was significantly higher than that of the chitosan film which has 55.6 %). The film also demonstrated strong antimicrobial activity with a reduction of 90 % in the growth of E. coli and S. aureus compared to the control. Additionally, the chitosan/KC/BV film showed a 75 % reduction in fungal growth compared to chitosan film. Furthermore, the water vapor permeability of the chitosan film was reduced as 5.38 with the addition of KC/BV. The degradation study revealed that the chitosan/KC film degraded by 88 % within 20 days under composting conditions. Additionally, fresh-cut apple slices were used to examine the effectiveness of chitosan/KC/BV film as a packaging material. The fruit's weight loss and browning index showed satisfactory food preservation. Our research suggests that the chitosan/KC/BV film has great potential for use in the food sector due to its strong antioxidant, antimicrobial, and biodegradable properties.


Asunto(s)
Antibacterianos , Antifúngicos , Antioxidantes , Benzaldehídos , Quitosano , Embalaje de Alimentos , Caolín , Quitosano/química , Quitosano/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Embalaje de Alimentos/métodos , Benzaldehídos/química , Benzaldehídos/farmacología , Caolín/química , Caolín/farmacología , Arcilla/química , Plásticos Biodegradables/química , Plásticos Biodegradables/farmacología , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Escherichia coli , Staphylococcus aureus
3.
Chem Commun (Camb) ; 60(54): 6917-6920, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38884113

RESUMEN

Ultra-small Ag nanoparticles (<5 nm) loaded on a kaolinite surface were successfully prepared in large batches by a dry-process, displaying excellent broad-spectrum antimicrobial ability and size-dependent activity. This Ag-loaded kaolinite (Ag@AT/K) inhibited the growth of pathogenic bacteria and accelerated wound healing in in vivo experiments on MRSA-infected wounds. This work provides a new strategy for the preparation of mineral-based nanoscale antibacterial materials.


Asunto(s)
Antibacterianos , Caolín , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Plata , Plata/química , Plata/farmacología , Caolín/química , Caolín/farmacología , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Tamaño de la Partícula , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Animales , Cicatrización de Heridas/efectos de los fármacos , Ratones
4.
Genes (Basel) ; 15(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38927683

RESUMEN

Grapevine varieties from "Douro Superior" (NE Portugal) experience high temperatures, solar radiation, and water deficit during the summer. This summer's stressful growing conditions induce nucleic acids, lipids, and protein oxidation, which cause cellular, physiological, molecular, and biochemical changes. Cell cycle anomalies, mitosis delay, or cell death may occur at the cellular level, leading to reduced plant productivity. However, the foliar application of kaolin (KL) can mitigate the impact of abiotic stress by decreasing leaf temperature and enhancing antioxidant defence. Hence, this study hypothesised that KL-treated grapevine plants growing in NE Portugal would reveal, under summer stressful growing conditions, higher progression and stability of the leaf mitotic cell cycle than the untreated (control) plants. KL was applied after veraison for two years. Leaves, sampled 3 and 5 weeks later, were cytogenetically, molecularly, and biochemically analysed. Globally, integrating these multidisciplinary data confirmed the decreased leaf temperature and enhanced antioxidant defence of the KL-treated plants, accompanied by an improved regularity and completion of the leaf cell cycle relative to the control plants. Nevertheless, the KL efficacy was significantly influenced by the sampling date and/or variety. In sum, the achieved results confirmed the hypothesis initially proposed.


Asunto(s)
Caolín , Hojas de la Planta , Vitis , Vitis/genética , Vitis/efectos de los fármacos , Vitis/crecimiento & desarrollo , Vitis/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Caolín/farmacología , Estaciones del Año , Estrés Fisiológico/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Antioxidantes/farmacología
5.
J Biomater Appl ; 39(2): 83-95, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38768480

RESUMEN

Tissue adhesives and sealants offer promising alternatives to traditional wound closure methods, but the existing trade-off between biocompatibility and strength is still a challenge. The current study explores the potential of a gelatin-alginate-based hydrogel, cross-linked with a carbodiimide, and loaded with two functional fillers, the hemostatic agent kaolin and cellulose fibres, to improve the hydrogel's mechanical strength and hemostatic properties for use as a sealant. The effect of the formulation parameters on the mechanical and physical properties was studied, as well as the biocompatibility and microstructure. The incorporation of the two functional fillers resulted in a dual micro-composite structure, with uniform dispersion of both fillers within the hydrogel, and excellent adhesion between the fillers and the hydrogel matrix. This enabled to strongly increase the sealing ability and the tensile strength and modulus of the hydrogel. The fibres' contribution to the enhanced mechanical properties is more dominant than that of kaolin. A combined synergistic effect of both fillers resulted in enhanced sealing ability (247%), tensile strength (400%), and Young's modulus (437%), compared to the unloaded hydrogel formulation. While the incorporation of kaolin almost did not affect the physical properties of the hydrogel, the incorporation of the fibres strongly increased the viscosity and decreased the gelation time and swelling degree. The cytotoxicity tests indicated that all studied formulations exhibited high cell viability. Hence, the studied new dual micro-composite hydrogels may be suitable for medical sealing applications, especially when it is needed to get a high sealing effect within a short time. The desired hemostatic effect is obtained due to kaolin incorporation without affecting the physical properties of the sealant. Understanding the effects of the formulation parameters on the hydrogel's properties enables the fitting of optimal formulations for various medical sealing applications.


Asunto(s)
Alginatos , Celulosa , Hemostáticos , Hidrogeles , Caolín , Ensayo de Materiales , Resistencia a la Tracción , Adhesivos Tisulares , Celulosa/química , Celulosa/farmacología , Hemostáticos/química , Hemostáticos/farmacología , Adhesivos Tisulares/química , Adhesivos Tisulares/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Alginatos/química , Caolín/química , Caolín/farmacología , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Módulo de Elasticidad , Viscosidad , Animales , Gelatina/química , Ratones , Supervivencia Celular/efectos de los fármacos
6.
Protoplasma ; 261(5): 965-974, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38607379

RESUMEN

Globodera pallida, an obligate sedentary endoparasite, is a major economic pest that causes substantial potato yield losses. This research aimed to study the effects of gene silencing of three FMRFamide-like peptides (FLPs) genes to reduce G. pallida infestation on potato plants by using kaolinite nanoclay as a carrier to deliver dsRNAs via drenching. A dsRNA dosage of 2.0 mg/ml silenced flp-32c by 89.5%, flp-32p by 94.6%, and flp-2 by 94.3%. J2s incubated for 5 and 10 h showed no phenotypic changes. However, J2s of G. pallida efficiently uptake dsRNA of all targeted genes after 15 h of incubation. On the other hand, J2s that had been kept for 24 h had a rigid and straight appearance. Under fluorescence microscopy, all dsRNA-treated nematodes showed fluorescein isothiocyanate (FITC) signals in the mouth, nervous system, and digestive system. The untreated population of J2s did not show any FITC signals and was mobile as usual. The drenching of potato cultivar Kufri Jyoti with the dsRNA-kaolinite formulations induced deformation and premature death of J2s, compared with untreated J2s that entered J3 or J4 stages. This study validates that the nanocarrier-delivered RNAi system could be employed effectively to manage G. pallida infestations.


Asunto(s)
Caolín , ARN Bicatenario , ARN Bicatenario/farmacología , Animales , Caolín/farmacología , Caolín/química , Arcilla/química , Solanum tuberosum/parasitología , Solanum tuberosum/genética , Control de Plagas/métodos , Tylenchoidea/efectos de los fármacos , Tylenchoidea/fisiología
7.
J Biomater Sci Polym Ed ; 35(7): 1064-1085, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38431865

RESUMEN

Severe trauma with massive active blood loss, including liver and spleen rupture, arterial bleeding and pelvic fracture, will lead disability, malformation and even death. Therefore, it is very important to develop new, fast and efficient hemostatic materials. In this study, a novel Gelatin/Kaolin (GE/KA) composite sponge was developed. Meanwhile, to further investigate the effect of kaolin content on sponge properties, we prepared four types of sponges: GE/5% KA, GE/10% KA, GE/15% KA and GE/20% KA. The results of coagulation test in vitro showed that compared to the other groups, there were more activated adhered platelets and red blood cells on the surface of GE/15% KA. The results of hemostasis test in vivo showed that compared to other experimental groups, the GE/15% KA group had significantly less hemostasis time (liver hemostasis model: 69.50 ± 2.81 s; femoral artery hemostasis model: 75.17 ± 3.06 s) and bleeding volume (liver hemostasis model: 219.02 ± 10.39 mg; femoral artery hemostasis model: 948.00 ± 50.69 mg), and was similar to the commercial hemostasis material group. Additionally, the material properties of the sponge were characterized and its biocompatibility was verified as well through cell experiments and in vivo embedding experiments. All these results indicate that the optimal content of kaolin is 15%, which provides a theoretical basis for subsequent research. All in all, the novel GE/KA composite sponge prepared in this study can be used as a multifunctional hemostatic wound dressing for the treatment of complex wounds under various trauma scenes.


Asunto(s)
Gelatina , Hemostasis , Hemostáticos , Caolín , Cicatrización de Heridas , Caolín/química , Caolín/farmacología , Animales , Cicatrización de Heridas/efectos de los fármacos , Hemostasis/efectos de los fármacos , Gelatina/química , Hemostáticos/farmacología , Hemostáticos/química , Hemostáticos/administración & dosificación , Hemorragia/tratamiento farmacológico , Ratones , Coagulación Sanguínea/efectos de los fármacos , Masculino , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos , Ensayo de Materiales
8.
Molecules ; 28(23)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38067486

RESUMEN

In recent years, the coagulation properties of inorganic minerals such as kaolin and zeolite have been demonstrated. This study aimed to assess the hemostatic properties of three local clays from China: natural kaolin from Hainan, natural halloysite from Yunnan, and zeolite synthesized by our group. The physical and chemical properties, blood coagulation performance, and cell biocompatibility of the three materials were tested. The studied materials were characterized by using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). All three clays showed different morphologies and particle size, and exhibited negative potentials between pH 6 and 8. The TGA and DSC curves for kaolin and halloysite were highly similar. Kaolin showed the highest water absorption capacity (approximately 93.8% ± 0.8%). All three clays were noncytotoxic toward L929 mouse fibroblasts. Kaolin and halloysite showed blood coagulation effects similar to that exhibited by zeolite, indicating that kaolin and halloysite are promising alternative hemostatic materials.


Asunto(s)
Hemostáticos , Zeolitas , Animales , Ratones , Arcilla/química , Caolín/farmacología , Caolín/química , China
9.
J Econ Entomol ; 116(6): 2095-2103, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37947189

RESUMEN

The production of almonds and pistachios in California's Central Valley employs insecticides for the management of their primary pest, navel orangeworm. The pyrethroid Bifenthrin is commonly used, and now a strain of Amyelois transitella Walker (Lepidoptera: Pyralidae) (R347) obtained from Kern County almond orchards with a history of Bifenthrin use has acquired >110-fold resistance toward pyrethroids. One method to improve control is to use additives and spray adjuvants, which are applied simultaneously with an insecticide to increase coverage and/or duration of control. We tested 2 levels of the naturally occurring clay Kaolin as an additive, alone and in combination with either Bifenthrin or the diamide Chlorantraniliprole, to determine if it could reduce feeding damage and decrease survival of pyrethroid-resistant A. transitella on almonds in the laboratory and improve the efficacy of Chlorantraniliprole in the field. Larval performance was measured for the strains R347 and ALM (34.7-fold resistance compared to susceptible lab strain) reared on treated almonds. Strain R347 had 1.9-fold greater survival and caused 1.3-fold more feeding damage than strain ALM across all treatments, although both strains were susceptible to the combination of Kaolin + insecticide. Kaolin synergized Bifenthrin for R347, decreasing survival by 10.0%. Kaolin did not reduce feeding damage for either strain. When combined with insecticide, feeding damage was similar to insecticide alone, but the addition of Kaolin to the insecticide generally decreased survival more than the insecticide alone. In the field, the addition of Kaolin to Chlorantraniprole during application helped retain activity against this challenging pest.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Prunus dulcis , Piretrinas , Animales , Insecticidas/farmacología , Caolín/farmacología , Resistencia a los Insecticidas , Piretrinas/farmacología
10.
Molecules ; 28(13)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37446820

RESUMEN

Natural kaolinite underwent advanced morphological-modification processes that involved exfoliation of its layers into separated single nanosheets (KNs) and scrolled nanoparticles as nanotubes (KNTs). Synthetic nanostructures have been characterized as advanced and effective oxaliplatin-medication (OXAP) delivery systems. The morphological-transformation processes resulted in a remarkable enhancement in the loading capacity to 304.9 mg/g (KNs) and 473 mg/g (KNTs) instead of 29.6 mg/g for raw kaolinite. The loading reactions that occurred by KNs and KNTs displayed classic pseudo-first-order kinetics (R2 > 0.90) and conventional Langmuir isotherms (R2 = 0.99). KNTs exhibit a higher active site density (80.8 mg/g) in comparison to KNs (66.3 mg/g) and raw kaolinite (6.5 mg/g). Furthermore, compared to KNs and raw kaolinite, each site on the surface of KNTs may hold up to six molecules of OXAP (n = 5.8), in comparison with five molecules for KNs. This was accomplished by multi-molecular processes, including physical mechanisms considering both the Gaussian energy (<8 KJ/mol) and the loading energy (<40 KJ/mol). The release activity of OXAP from KNs and KNTs exhibits continuous and regulated profiles up to 100 h, either by KNs or KNTs, with substantially faster characteristics for KNTs. Based on the release kinetic investigations, the release processes have non-Fickian transport-release features, indicating cooperative-diffusion and erosion-release mechanisms. The synthesized structures have a significant cytotoxicity impact on HCT-116 cancer cell lines (KNs (71.4% cell viability and 143.6 g/mL IC-50); KNTs (11.3% cell viability and 114.3 g/mL IC-50). Additionally, these carriers dramatically increase OXAP's cytotoxicity (2.04% cell viability, 15.4 g/mL IC-50 (OXAP/KNs); 0.6% cell viability, 4.5 g/mL IC-50 (OXAP/KNTs)).


Asunto(s)
Caolín , Nanotubos , Caolín/farmacología , Caolín/química , Oxaliplatino/farmacología , Cinética , Preparaciones Farmacéuticas
11.
J Hazard Mater ; 457: 131727, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37257383

RESUMEN

Soil environment is a vital place for the occurrence and spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Extracellular DNA-mediated transformation is an important pathway for ARGs horizontal transfer and widely exists in soil environment. However, little information is available on how common soil components affect ARGs transformation. Here, three minerals (quartz, kaolinite, and montmorillonite) and three organic matters (humic acid, biochar, and soot) were selected as typical soil components. A small amount in suspension (0.2 g/L) of most soil components (except for quartz and montmorillonite) promoted transformant production by 1.1-1.6 folds. For a high amount (8 g/L), biochar significantly promoted transformant production to 1.5 times, kaolinite exerted a 30 % inhibitory effect. From the perspective of plasmid, biochar induced a higher proportion of supercoiled plasmid than kaolinite; more dissolved organic matter and metal ions facilitated plasmid aggregation under the near-neutral pH, thus promoted transformation. As for the influence of materials on recipient, although biochar and kaolinite both increased reactive oxygen species (ROS) level and membrane permeability, biochar up-regulated more ROS related genes, resulting in intracellular ROS production and up-regulating the expression of carbohydrate metabolism and transformation related genes. While kaolinite inhibited transformation mainly by causing nutrient deficiency.


Asunto(s)
Antibacterianos , Suelo , Antibacterianos/farmacología , Genes Bacterianos , Caolín/farmacología , Especies Reactivas de Oxígeno/farmacología , Antagonistas de Receptores de Angiotensina/farmacología , Bentonita/farmacología , Cuarzo/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Bacterias/genética , Farmacorresistencia Microbiana/genética , Plásmidos/genética
12.
Biomater Adv ; 150: 213424, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37068405

RESUMEN

Increased mortalities associated with uncontrolled and excessive bleeding is still of paramount concern in the clinics, caregivers and military medics. Herein, we designed a shape memory cryogel based on chitosan (C) and functionalized-dextran (D), incorporated with Kaolin (K) and calcium (Ca2+) as haemostatic agents. The developed cryogel (CDKCa) exhibits a uniform interconnected porous architecture with profound fluid absorption ability, rapid blood clotting, stable clot formation and good antibacterial activity. The CDKCa elucidates significantly less clotting time (~30 s; in-vitro) and increased aggregation and activation of platelets/red blood cells in comparison to the control groups and commercial dressings (Axiostat and QuikClot). The developed CDKCa also significantly reduced the aPTT and PT values by ~58 % and 31 % respectively, leading to the activation of intrinsic and extrinsic coagulation cascades. The CDKCa cryogel displays enhanced mechanical stability, flexibility and a good shape memory, a property quintessential to cease uncontrolled bleeding in irregular and non-compressible wounds. Further, the Kaolin and Ca2+ incorporated shape memory CDKCa cryogel demonstrates a rapid blood coagulation and stable clot formation in different compressible and non-compressible rat liver and femur hemorrhagic models. In summary, the endorsed results of CDKCa suggest that the design, fabrication and excellent clotting ability may attribute to high haemostatic efficiency of CDKCa dressing and have a great potential to prevent uncontrollable hemorrhages.


Asunto(s)
Quitosano , Hemostáticos , Humanos , Hemostáticos/farmacología , Hemostáticos/uso terapéutico , Quitosano/farmacología , Quitosano/uso terapéutico , Caolín/farmacología , Caolín/uso terapéutico , Criogeles , Dextranos/farmacología , Dextranos/uso terapéutico , Hemorragia/prevención & control , Vendajes , Antibacterianos
13.
Physiol Plant ; 175(1): e13844, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36539940

RESUMEN

High irradiance and increased air temperature during extreme weather conditions affect tree crops and impact the yield and quality of fruits. Moreover, flowering and fruit set of Citrus are likely impaired by UV radiation and/or reduced carbon assimilation, which increase reactive oxygen species production and damage the leaf photosynthetic apparatus. Particle coating films sprayed on leaves have been offered as a way to minimize crop losses due to the climate change scenario, even though the extent of leaf protection is not characterized. We evaluated the use of two protective films on the oxidative stress and leaf photosynthesis of sweet orange trees exposed to varying daylight levels. Trees were maintained under full sun light, sprayed or not (control) with kaolin or calcium carbonate, and under reduced irradiance using either aluminum shade cloth 50% or anti-UV transparent plastic. Kaolin or calcium carbonate reflected 20%-30% of the incident light on the leaf surface compared to leaves not sprayed and under full sunlight. Leaves with coating exhibited improved CO2 assimilation and photosystem II efficiency, and lower leaf temperatures over time. In addition, the coating protected leaves against excess irradiance due to dissipation of excess energy into the photosynthetic apparatus (NPQt). Nonenzymatic mechanisms for UV protection, such as carotenoids, were higher in full sun control plants than in leaf-coated plants. Comparable responses were observed on trees maintained covered either by the cloth or the plastic film. Finally, we conclude that the use of suspension particles mitigates the harmful effects of excess UV irradiance and temperature in sweet orange trees.


Asunto(s)
Citrus , Árboles , Árboles/fisiología , Temperatura , Caolín/farmacología , Fotosíntesis/efectos de la radiación , Hojas de la Planta/fisiología
14.
Braz. J. Pharm. Sci. (Online) ; 59: e21460, 2023. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1439502

RESUMEN

Abstract Clay minerals are still widely used in pharmaceutical products for human health and cosmetic purposes. Pre-formulation studies were conducted to identify solid-state properties of pink clay, a sample from Diamantina, Brazil. Among the solid properties to be analyzed, we have selected type identification, iron phases, crystallinity, powder flow characteristics, thermal behavior, and non-isothermal phase transition kinetics. The pink clay is composed of (1:1) clay type and kaolinite as the main component. The Mössbauer spectrum of pink clay shows Fe3+(α-Fe2O3) Clay minerals are still widely used in pharmaceutical products for human health and cosmetic purposes. Pre-formulation studies were conducted to identify solid-state properties of pink clay, a sample from Diamantina, Brazil. Among the solid properties to be analyzed, we have selected type identification, iron phases, crystallinity, powder flow characteristics, thermal behavior, and non-isothermal phase transition kinetics. The pink clay is composed of (1:1) clay type and kaolinite as the main component. The Mössbauer spectrum of pink clay shows Fe3+(α-Fe2O3) hematite, Fe2+, and Fe3+ with large Δ/2ξq of about 2.80 and 2.69 mm.s-1 respectively, related to iron silicates, most likely pyroxene, and a superparamagnetic Fe3+. Pink clay exhibits poor flow properties. The thermal behavior indicates a phase-transition between 400 - 600 ºC associated with the dehydroxylation of the pink clay system requiring ~300 kJ mol-1, being constant until the process reaches a conversion of ~50% when the energy is enhanced to ~530 kJ mol-1, concluding the whole dehydroxylation process (α=80%). Solid-state properties and characteristics found for the pink clay must be considered for the proper design of formulations. This type of clay shows unique pharmaceutical properties that can be favorably exploited by the cosmetic industry


Asunto(s)
Brasil/etnología , Arcilla/clasificación , Polvos/análisis , Caolín/farmacología
15.
Can J Vet Res ; 86(4): 316-319, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36211214

RESUMEN

The viscoelastic coagulation monitor (VCM) is described as a point-of-care analyzer relying on activation of fresh whole blood (FWB) via contact between 2 glass plates. Kaolin is used as an activator in thromboelastography to reduce variability and shorten clotting times. The goal of this study was to compare VCM results from kaolin-activated, recalcified citrated samples with that from FWB. The VCM testing was performed using FWB and kaolin-activated, recalcified citrated samples. The VCM results were recorded for clot time (CT; seconds), clot formation time (CFT; seconds), alpha (degree), amplitude at 10 and 20 minutes (A10 and A20; VCM units), maximum clot firmness (MCF; VCM units), and lysis index (LI; %). Values were compared using a t-test or Wilcoxon-Mann-Whitney test, with a P-value < 0.05 considered significant. Variability between samples was calculated using Levene's test. The VCM kaolin activation resulted in significantly faster CT and CFT (P < 0.0001), higher alpha angle (P < 0.001), and higher A10 and A20 (P = 0.007, P = 0.015) compared to FWB. There was no difference in MCF, LI30, or LI45. There was no difference in variability identified. The addition of kaolin to recalcified citrated whole blood VCM samples results in more rapid clotting of FWB alone and could be considered for clinical use in dogs.


Le moniteur de coagulation viscoélastique (VCM) évalue l'hémostase au point de service en utilisant du sang entier frais activé au contact de deux disques de verre. Le kaolin est un activateur utilisé en thromboélastographie pour réduire la variabilité et raccourcir le temps de coagulation.Le but de cette étude était de comparer les résultats du VCM obtenus sur des échantillons citratés recalcifiés et activés par du kaolin, avec ceux obtenus sur sang entier frais. Les échantillons sanguins ont été prélevés sur des chiens sains. Les tests avec le VCM ont été réalisés sur des échantillons de sang entier frais et sur des échantillons de sang citraté recalcifié et activé par du kaolin. Les résultats du VCM ont été enregistrés : temps de coagulation (CT; secondes), temps de formation du caillot (CFT; secondes), angle alpha (degrés), amplitude à 10 et 20 minutes (A10 et A20; unités VCM), fermeté maximale du caillot (MCF; unités VCM), index de lyse à 30 et 45 minutes après la MCF (LI; pourcentage). Les valeurs ont été comparées à l'aide d'un un test t apparié ou un test de Wilcoxon-Mann-Whitney, avec une valeur P < 0,05 considérée comme significative. La variabilité entre les échantillons a été calculée à l'aide d'un test de Levene.Les résultats du VCM réalisé sur les échantillons activés par du kaolin présentaient une diminution significative du CT et CFT (P < 0,0001) ainsi qu'une augmentation significative de l'angle alpha (P < 0,001) et de A10 et A20 (P = 0,007, P = 0,015). Aucune différence n'a été démontrée dans la MCF, l'index LI30 ou LI45. Aucune différence de variabilité n'a été identifiée.L'ajout du kaolin aux échantillons VCM de sang entier citraté recalcifié aboutit à une activation de la coagulation plus rapide que par simple contact avec les disques de verre et pourrait être envisagé pour l'usage clinique chez le chien.(Traduit par les auteurs).


Asunto(s)
Caolín , Sistemas de Atención de Punto , Animales , Bencenoacetamidas , Coagulación Sanguínea , Pruebas de Coagulación Sanguínea/métodos , Pruebas de Coagulación Sanguínea/veterinaria , Citratos , Ácido Cítrico , Perros , Caolín/farmacología , Piperidonas , Tromboelastografía/métodos , Tromboelastografía/veterinaria
16.
Pest Manag Sci ; 78(11): 4753-4763, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35894950

RESUMEN

BACKGROUND: The citrus greening disease or Huanglongbing (HLB) is the most devastating disease of citrus crops. Trioza erytreae is a vector of HLB. Since its introduction in Europe, the insect reached the northern region of Spain and the southern region of Portugal, threatening relevant citrus production areas. Limiting the spread of HLB vectors is mandatory to prevent this disease. In this work, we assessed the effect of kaolin, a white mineral clay, on the landing, settling behavior and feeding behavior of Trioza erytreae on lemon plants. RESULTS: After kaolin application, the number of plants on which the insect was found was significantly lower than on untreated plants in the laboratory and in the field. Moreover, there were significantly fewer T. erytreae and a shorter duration of phloem-related events on kaolin-treated than untreated plants. CONCLUSION: The use of kaolin could be a suitable and efficient tool for inclusion into integrated pest management programs or organic production to reduce populations of T. erytreae and subsequently limit the spread of HLB in citrus crops. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Citrus , Hemípteros , Rhizobiaceae , Animales , Arcilla , Caolín/farmacología , Floema , Enfermedades de las Plantas/prevención & control
17.
J Biomed Nanotechnol ; 18(3): 796-806, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35715900

RESUMEN

The novel multifunctional electrospun textiles were fabricated by incorporating sheet-like kaolinite and silver nanoparticles (AgNps) into a polyurethane (PU) textile by using electrostatic spinning to promote wound-healing process. Threedimensional network of PU electrospun textiles offered an appropriate framework for loading kaolinite nanosheets and AgNps. Moreover, the kaolinite nanosheets healed bleeding wounds by accelerating plasma absorption, increasing blood cell concentrations, and stimulating coagulation factors. Furthermore, the AgNps killed microbes by destroying the cell membrane, while the deleterious effects were controlled by incorporation into the electrospun textile. The therapeutic effects of multifunctional electrospun textile in treating full-thickness abdominal wall defect were explored. The wound healing process could be accelerated via the textile by restoring the abdominal physiological environment, reducing the inflammatory response, and promoting collagen deposition, angiogenesis, and epithelization.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos/farmacología , Caolín/farmacología , Nanopartículas del Metal/uso terapéutico , Poliuretanos/farmacología , Plata/farmacología , Textiles , Cicatrización de Heridas
18.
Am Surg ; 88(11): 2619-2625, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35576492

RESUMEN

BACKGROUND: Age, race, and gender differences in coagulation status of healthy volunteers have been reported in previous case series; however, rigorous multivariate analysis adjusting for these factors is lacking. We aimed to investigate the effects of age, race, and gender on baseline coagulation status in healthy volunteers. METHODS: Thirty healthy volunteer controls with no history of bleeding or thrombotic events and no previous anticoagulant or antiplatelet use were recruited. Citrated and heparinized blood samples were drawn, and kaolin and platelet-mapping thromboelastography (TEG) assays performed. RESULTS: Thirty participants had a mean age of 37, mean body mass index of 29 kg/m2, and were 47% African-American and 70% female. Women were significantly older than men (40 ± 11 y vs 28 ± 7 y, P = .002); there were no significant differences in demographics by race. Multivariate analysis of variance for the effect of age, race, and gender across TEG parameters yielded evidence for gender differences in hypercoagulability (Pillai's trace P = .02), which appear to be driven by differences in K-time, alpha angle, maximal amplitude, and G parameter. Women were hypercoagulable compared to men, as manifested by shorter K-time, steeper alpha angle, higher maximal amplitude, and larger G parameter. DISCUSSION: Women at baseline have relatively hypercoagulable fibrin deposition kinetics, platelet contributions to clot formation, and overall clot strength compared to men, even when adjusted for age and race. Additional research is needed to specifically detail the key patient-level factors, clinical implications, and opportunities for tailored therapy related to gender-associated hypercoagulability.


Asunto(s)
Trombofilia , Trombosis , Adulto , Anticoagulantes , Femenino , Fibrina , Humanos , Caolín/farmacología , Masculino , Tromboelastografía , Trombofilia/diagnóstico
19.
Molecules ; 27(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35458768

RESUMEN

Uncontrolled hemorrhage from trauma or surgery can lead to death. In this study, chitosan/kaolin (CSK) and chitosan/montmorillonite (CSMMT) composites were prepared from chitosan (CS), kaolin (K), and montmorillonite (MMT) as raw materials to control bleeding. The physiochemical properties and surface morphology of CSK and CSMMT composites were analyzed by Fourier transform infrared spectrometry (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta potentials, and X-ray fluorescence (XRF). The hemostatic mechanism was measured in vitro by activated partial thromboplastin time (APTT), prothrombin time (PT), in vitro clotting time, erythrocyte aggregation, and thromboelastogram (TEG). The hemostasis ability was further verified by using tail amputation and arteriovenous injury models in rats. The biocompatibility of CSK and CSMMT was evaluated by in vitro hemolysis, cytotoxicity assays, as well as acute toxicity test and skin irritation tests. The results show that CSK and CSMMT are promising composite materials with excellent biocompatibility and hemostatic properties that can effectively control bleeding.


Asunto(s)
Quitosano , Hemostáticos , Animales , Bentonita/química , Bentonita/farmacología , Quitosano/química , Quitosano/farmacología , Arcilla , Hemorragia/tratamiento farmacológico , Hemostáticos/química , Hemostáticos/farmacología , Caolín/farmacología , Ratas , Espectroscopía Infrarroja por Transformada de Fourier
20.
J Zoo Wildl Med ; 53(1): 133-140, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35339158

RESUMEN

Thromboelastography (TEG) provides a global assessment of hemostasis and fibrinolysis and has broad applications to identify and monitor coagulation dysfunction in veterinary patients. Although alpacas are susceptible to a wide variety of coagulopathies, the assessment of TEG has not been reported in clinically healthy alpacas to date. The purpose of this study was to evaluate the analytical performance of recombinant human tissue factor (rhTF)- and kaolin-activated TEG and to establish reference intervals for TEG parameters (reaction [R] and clotting [K] times, angle [α], maximum amplitude [MA], and shear elastic modulus [G]) in healthy, adult alpacas. Kaolin and rhTF-activated TEG were performed using citrated whole blood samples from 20 clinically healthy, nonpregnant, adult Huacaya alpacas each after 30 min of sample storage at room temperature. Six individuals of a related species, dromedary camels, were also sampled for comparative purposes. All data were presented descriptively, assessed for normality, and compared using either independent-sample t tests or Mann-Whitney U tests, with P ≤ 0.05 considered significant. Reference intervals were calculated using a robust method and Box-Cox-transformed data. Mean TEG values (reference intervals) were determined for rhTF-activated TEG as follows: R 6.99 min (3.41-12.71), K 3.43 min (1.61-6.42), α 48.51° (27.21-67.38), MA 52.05 mm (21.53-65.92), and G 5.71 kdyn/cm2 (1.87-9.60), while mean values (reference intervals) for kaolin-activated TEG included R 7.72 min (4.48-11.43), K 4.24 min (2.03-9.20), α 45.06° (23.66-64.20), MA 52.18 mm (33.49-66.63), and G 5.78 kdyn/cm2 (NR-9.66). None of the measured TEG values differed significantly between activators, suggesting that activator choice may have a limited effect on TEG parameters in healthy alpacas. TEG results in alpacas were comparable to those of dromedary camels. These results will thus provide a useful starting point in the evaluation of hemostasis in adult camelids.


Asunto(s)
Camélidos del Nuevo Mundo , Tromboelastografía , Animales , Coagulación Sanguínea , Camelus , Caolín/farmacología , Tromboelastografía/veterinaria
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