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1.
Odontology ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958828

RESUMEN

Hyaluronic acid (HA), known for diverse properties, was investigated for its potential in dental pulp therapy. This study investigated the potential of HA in dental pulp therapy by examining the physical properties and effects of zinc oxide eugenol (ZOE) pulpotomy materials containing varying HA concentrations on rat molar teeth. In vitro tests assessed compressive strength and hardness of ZOE materials blended with HA (0.5%, 1%, 3%) and HA gels (0.54%, 0.8%). 120 samples, encompassing the control group, underwent compressive strength testing, while 60 samples were designated for hardness assessment. In vivo experiments on rat molars studied histological effects of HA-containing ZOE on dental pulp over 1 week and 1 month. Gels with HA concentrations of 0.5%, 1%, and 0.54% were used in pulpotomy on 22 rats. Each rat underwent the procedure on four teeth, with one tooth serving as a control, totaling 88 teeth subjected to the intervention. In the analyses, SPSS 22.0 was used and the significance level was set at P = 0.05. Findings showed that HA at 0.5% maintained compressive strength, but higher concentrations decreased mechanical properties significantly (P = 0.001). Histological assessments indicated better outcomes with lower HA concentrations in terms of odontoblast layer continuity (P = 0.005 at 1 month) and pulp vitality (P = 0.001 at 1 week and P = 0.018 at 1 month). The study suggests HA holds promise for pulpotomy and regenerative endodontic treatments, but further research is needed to understand long-term clinical implications.

2.
Int J Mol Sci ; 25(6)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38542348

RESUMEN

Despite a long period of application of metal implants, carbon-carbon medical composites are also widely used for bone defect prosthesis in surgery, dentistry, and oncology. Such implants might demonstrate excellent mechanical properties, but their biocompatibility and integration efficiency into the host should be improved. As a method of enhancing, the electrophoretic deposition of fine-dispersed hydroxyapatite (HAp) on porous carbon substrates might be recommended. With electron microscopy, energy dispersion X-ray and Raman spectroscopy, and X-ray diffraction, we found that the deposition and subsequent heat post-treatment (up to the temperature of 400 °C for 1 h) did not lead to any significant phase and chemical transformations of raw non-stoichometric HAp. The Ca/P ratio was ≈1.51 in the coatings. Their non-toxicity, cyto- and biocompatibility were confirmed by in vitro and in vivo studies and no adverse reactions and side effects had been detected in the test. The proposed coating and subsequent heat treatment procedures provided improved biological responses in terms of resorption and biocompatibility had been confirmed by histological, magnetic resonance and X-ray tomographic ex vivo studies on the resected implant-containing biopsy samples from the BDF1 mouse model. The obtained results are expected to be useful for modern medical material science and clinical applications.


Asunto(s)
Carbono , Materiales Biocompatibles Revestidos , Animales , Ratones , Carbono/química , Materiales Biocompatibles Revestidos/química , Fosfatos de Calcio , Durapatita/química , Prótesis e Implantes , Difracción de Rayos X
3.
Int Ophthalmol ; 44(1): 73, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349587

RESUMEN

PURPOSE: To provide a simple alternative acute ocular toxoplasmosis model with great reproducibility for experimental tests that demand monitoring of the ocular lesion. METHODS: ME49-wt and ME49-GFP tachyzoites from cell culture were used to infect male C57BL6 mice by intraperitoneal injection. B1 expression by real-time polymerase chain reaction (qPCR) assay was used to detect the presence of T. gondii in ocular tissue at the beginning of the infection. Fluorescence microscopy and histopathology analysis were carried out to assess the evolution of the acute infection up to 20 days in both eyes of infected mice. RESULTS: All mice infected with the 104 tachyzoites showed B1 expression in the retina of both eyes, in the RPE (retinal pigment epithelium), and choroid structures, after 5 days of infection. Tachyzoites of the ME49-GFP strain were easily detected by fluorescence microscopy in the retina tissue of mice after 5 days post-infection. After 20 days, mice inflammatory cell infiltrates and a disorganized morphology of the retinal laminar architecture were observed. CONCLUSION: Infection of C57BL6 mice via intraperitoneal with 104 tachyzoites of the ME49-GFP strain from cell culture is a suitable model for acute ocular toxoplasmosis. This model has great reproducibility in establishing the ocular lesion since day 5 post-infection. This model can be suitable for experimental tests of chemotherapy and the investigation of the role of the immune response on the development of uveitis.


Asunto(s)
Toxoplasmosis Ocular , Masculino , Animales , Ratones , Toxoplasmosis Ocular/diagnóstico , Reproducibilidad de los Resultados , Ratones Endogámicos C57BL , Retina , Epitelio Pigmentado de la Retina
4.
AAPS PharmSciTech ; 24(8): 248, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38030938

RESUMEN

Burns alter the normal skin barrier and affect various host defense processes that help prevent infections. An ineffective repair process can lead to serious damage, such as the onset of an infection or skin loss, which can then harm the surrounding tissues and ultimately the entire organism. This study aims to prepare in situ gels containing metformin hydrochloride, a compound known for its wound healing properties. To achieve this, in situ gels were prepared using three different gelling agents (Poloxamer 407®, Carbopol 934®, and sodium carboxymethyl cellulose (Na-CMC)) and three different concentrations of metformin hydrochloride (4 mg/g, 6 mg/g, and 8 mg/g), which were optimized through experimental design. Metformin concentration and gelling agent type were independent variables, and the loaded amount and the percentage of metformin released after 150 min were chosen as dependent variables in the optimization process. After determining the optimum values of the dependent variables according to the ANOVA analysis results, in vivo studies were conducted with optimized hydrogel formulations. Two groups, each consisting of seven Wistar rats with a burn model, were treated with metformin-poloxamer 407® gels at doses of 4 mg/g and 8 mg/g for 29 days. The results were then compared to untreated and placebo gel groups. Rats treated with in situ Poloxamer 407® hydrogels containing metformin hydrochloride showed a significant reduction in the size of the burned area after 29 days of treatment. However, for a comprehensive understanding of the wound healing mechanism, further studies such as immuno-histochemical and cell culture studies are needed.


Asunto(s)
Quemaduras , Metformina , Ratas , Animales , Hidrogeles/química , Poloxámero/química , Ratas Wistar , Proyectos de Investigación , Quemaduras/tratamiento farmacológico
5.
Int J Mol Sci ; 23(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36012646

RESUMEN

Glaucoma is the second leading cause of blindness in the world. Despite the fact that many treatments are currently available for eye diseases, the key issue that arises is the administration of drugs for long periods of time and the increased risk of inflammation, but also the high cost of eye surgery. Consequently, numerous daily administrations are required, which reduce patient compliance, and even in these conditions, the treatment of eye disease is too ineffective. Micellar polymers are core-shell nanoparticles formed by the self-assembly of block or graft copolymers in selective solvents. In the present study, polymeric micelles (PMs) were obtained by dialysis from smart biocompatible poly(ε-caprolactone)-poly(N-vinylcaprolactam-co-N-vinylpyrrolidone) [PCL-g-P(NVCL-co-NVP)] graft copolymers. Two copolymers with different molar masses were studied, and a good correlation was noted between the micellar sizes and the total degree of polymerisation (DPn) of the copolymers. The micelles formed by Cop A [PCL120-g-P(NVCL507-co-NVP128)], with the lowest total DPn, have a Z-average value of 39 nm, whereas the micellar sizes for Cop B [PCL120-g-P(NVCL1253-co-NVP139)] are around 47 nm. These PMs were further used for the encapsulation of two drugs with applications for the treatment of eye diseases. After the encapsulation of Dorzolamide, a slight increase in micellar sizes was noted, whereas the encapsulation of Indomethacin led to a decrease in these sizes. Using dynamic light scattering, it was proved that both free and drug-loaded PMs are stable for 30 days of storage at 4 °C. Moreover, in vitro biological tests demonstrated that the obtained PMs are both haemo- and cytocompatible and thus can be used for further in vivo tests. The designed micellar system proved its ability to release the encapsulated drugs in vitro, and the results obtained were validated by in vivo tests carried out on experimental animals, which proved its high effectiveness in reducing intraocular pressure.


Asunto(s)
Glaucoma , Micelas , Animales , Portadores de Fármacos , Glaucoma/tratamiento farmacológico , Poliésteres , Polietilenglicoles , Polímeros , Diálisis Renal
6.
Parasitol Res ; 120(1): 153-159, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33174071

RESUMEN

The objective of this study was to compare the results of an in vitro egg hatch test (EHT), micro-agar larval development test (MALDT) and in vivo faecal egg count reduction test (FECRT) between worm strains obtained from goats and sheep identically infected with the gastrointestinal parasitic nematode Haemonchus contortus. Results from the in vivo and in vitro tests were compared with benzimidazole (BZ)-resistance-associated ß-tubulin allele frequencies determined using Pyrosequencing™. BZ resistance was not detected by the in vivo FECRT, where reductions of > 99% for both the resistant and the susceptible H. contortus strains were detected in both species. Discriminating doses in EHT and MALDT for the resistant strain indicated a low level (approx. 25%) of resistant individuals. Genotyping indicated that the susceptible strain had 10% BZ-resistant ß-tubulin codon 200 alleles and the resistant strain had 26% respective resistant alleles. The in vitro tests and allele-frequency distribution suggested low levels of resistance in both strains; however, the FECRT did not support the evidence of resistant individuals of either strain in either species, suggesting a potential underestimation of low-level resistance in sheep and goats when employing this test.


Asunto(s)
Antihelmínticos/farmacología , Bencimidazoles/farmacología , Resistencia a Medicamentos , Recuento de Huevos de Parásitos/veterinaria , Alelos , Animales , Antihelmínticos/uso terapéutico , ADN de Helmintos/genética , Resistencia a Medicamentos/efectos de los fármacos , Resistencia a Medicamentos/genética , Heces/parasitología , Frecuencia de los Genes , Cabras , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Hemoncosis/veterinaria , Haemonchus/efectos de los fármacos , Haemonchus/genética , Haemonchus/aislamiento & purificación , Proteínas del Helminto/genética , Pruebas de Sensibilidad Parasitaria , Ovinos , Tubulina (Proteína)/genética
7.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34638973

RESUMEN

The search for promising biomolecules such as chitooligosaccharides (COS) has increased due to the need for healing products that act efficiently, avoiding complications resulting from exacerbated inflammation. Therefore, this study aimed to produce COS in two stages of hydrolysis using chitosanases derived from Bacillus toyonensis. Additionally, this study aimed to structurally characterize the COS via mass spectrometry, to analyze their biocompatibility in acute toxicity models in vivo, to evaluate their healing action in a cell migration model in vitro, to analyze the anti-inflammatory activity in in vivo models of xylol-induced ear edema and zymosan-induced air pouch, and to assess the wound repair action in vivo. The structural characterization process pointed out the presence of hexamers. The in vitro and in vivo biocompatibility of COS was reaffirmed. The COS stimulated the fibroblast migration. In the in vivo inflammatory assays, COS showed an antiedematogenic response and significant reductions in leukocyte migration, cytokine release, and protein exudate. The COS healing effect in vivo was confirmed by the significant wound reduction after seven days of the experiment. These results indicated that the presence of hexamers influences the COS biological properties, which have potential uses in the pharmaceutical field due to their healing and anti-inflammatory action.


Asunto(s)
Antiinflamatorios/administración & dosificación , Materiales Biocompatibles/administración & dosificación , Quitosano/administración & dosificación , Enfermedades del Oído/tratamiento farmacológico , Edema/tratamiento farmacológico , Oligosacáridos/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos , Células 3T3 , Animales , Antiinflamatorios/química , Bacillus/enzimología , Materiales Biocompatibles/química , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Citocinas/metabolismo , Modelos Animales de Enfermedad , Enfermedades del Oído/inducido químicamente , Edema/inducido químicamente , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Glicósido Hidrolasas/química , Hidrólisis , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Oligosacáridos/química
8.
Allergy ; 75(12): 3112-3123, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32990987

RESUMEN

A correct diagnosis of drug hypersensitivity reactions (DHRs) is very important for both the patient and health system. However, DHRs diagnosis is complex, time consuming, requires trained personnel, is not standardized for many drugs, involves procedures not exempt of risk, and in most cases lacks standardized in vivo and in vitro tests. Thus, there is an urgent need for improving the different approaches to diagnose patients with suspected DHRs. In this review, we have analyzed the advances performed in immediate and nonimmediate DHRs diagnosis during the last two years and obtained several conclusions: the significant heterogeneity in current practice among centers illustrates the need to re-evaluate, update, and standardize in vivo tests and protocols for the diagnosis and management of patients with suspected drug allergy. Regarding in vitro tests, the latest studies have focused on increasing their sensitivity or on establishing the sensitivity and specificity for the tests performed with new drugs. There seems to be a consensus about combining in vivo and in vitro tests as the best way to increase the diagnostic accuracy.


Asunto(s)
Hipersensibilidad a las Drogas , Hipersensibilidad Inmediata , Hipersensibilidad a las Drogas/diagnóstico , Humanos , Técnicas In Vitro , Pruebas Cutáneas
9.
Exp Eye Res ; 197: 108117, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32598972

RESUMEN

Large animal models of optic nerve injury are essential for translating novel findings into effective therapies due to their similarity to humans in many respects. However, most current tests evaluating the integrity of retinal ganglion cells (RGCs) and optic nerve (ON) are based on rodent animal models. We aimed to evaluate and optimize the in vivo methods to assess RGCs and ON's function and structure in large animals in terms of reproducibility, simplicity and sensitivity. Both goats and rhesus macaques were employed in this study. By using goats, we found anesthesia with isoflurane or xylazine resulted in different effects on reproducibility of flash visual evoked potential (FVEP) and pattern electroretinogram (PERG). FVEP with the large-Ganzfeld stimulator was significantly more stable than that with mini-Ganzfeld stimulator. PERG with simultaneous binocular stimulation, with superior simplicity over separate monocular stimulation, was appliable in goats due to undetectable interocular crosstalk of PERG signals. After ON crush in goats, some FVEP components, PERG, OCT and PLR demonstrated significant changes, in line with the histological study. By using rhesus macaque, we found the implicit time of PVEP, FVEP and PERG were significantly more reproducible than amplitudes, and OCT and PLR demonstrated small intersession variation. In summary, we established an optimized system to evaluate integrity of RGCs and ON in large animals in vivo, facilitating usage of large animal models of optic nerve diseases.


Asunto(s)
Electrorretinografía/métodos , Traumatismos del Nervio Óptico/diagnóstico , Nervio Óptico/patología , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Animales , Modelos Animales de Enfermedad , Cabras , Macaca mulatta , Masculino , Traumatismos del Nervio Óptico/fisiopatología , Reproducibilidad de los Resultados
10.
Int J Mol Sci ; 21(20)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066080

RESUMEN

Poly(l-lactide-co-glycolide) (PLGA) porous scaffolds were modified with collagen type I (PLGA/coll) or hydroxyapatite (PLGA/HAp) and implanted in rabbits osteochondral defects to check their biocompatibility and bone tissue regeneration potential. The scaffolds were fabricated using solvent casting/particulate leaching method. Their total porosity was 85% and the pore size was in the range of 250-320 µm. The physico-chemical properties of the scaffolds were evaluated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), sessile drop, and compression tests. Three types of the scaffolds (unmodified PLGA, PLGA/coll, and PLGA/HAp) were implanted into the defects created in New Zealand rabbit femoral trochlears; empty defect acted as control. Samples were extracted after 1, 4, 12, and 26 weeks from the implantation, evaluated using micro-computed tomography (µCT), and stained by Masson-Goldner and hematoxylin-eosin. The results showed that the proposed method is suitable for fabrication of highly porous PLGA scaffolds. Effective deposition of both coll and HAp was confirmed on all surfaces of the pores through the entire scaffold volume. In the in vivo model, PLGA and PLGA/HAp scaffolds enhanced tissue ingrowth as shown by histological and morphometric analyses. Bone formation was the highest for PLGA/HAp scaffolds as evidenced by µCT. Neo-tissue formation in the defect site was well correlated with degradation kinetics of the scaffold material. Interestingly, around PLGA/coll extensive inflammation and inhibited tissue healing were detected, presumably due to immunological response of the host towards collagen of bovine origin. To summarize, PLGA scaffolds modified with HAp are the most promising materials for bone tissue regeneration.


Asunto(s)
Osteocondrosis/cirugía , Poliglactina 910/química , Andamios del Tejido/química , Animales , Regeneración Ósea , Colágeno/química , Hidroxiapatitas/química , Porosidad , Conejos , Andamios del Tejido/efectos adversos
11.
J Appl Microbiol ; 126(4): 1245-1256, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30614169

RESUMEN

AIMS: There is interest in using probiotics such as Lactobacillus species to control canine intestinal infections. The bacterial species should be of canine intestinal origin exhibiting host specificity. Bacterial strains were isolated from dog faecal samples and characterized to select specific probiotics as dietary supplements in feed, promoting health status. METHODS AND RESULTS: Bacterial strains have been screened for their probiotic properties including survival to gastric and pancreatic juices and bile salts, resistance to antibiotics and antipathogenicity. Five of 14 isolated Lactobacillus strains were tolerant to gastric stress. They were also resistant to clindamycin and with a significant antimicrobial capacity towards the pathogenic strains tested, variable according to the strain. They were identified by morphological and molecular characterization comparing the 16S rRNA gene sequence with the blast database. Three strains were identified as Lactobacillus reuteri and two as Lactobacillus johnsonii. Sugar fermentation profiles and adhesion to HT29 epithelial cells have been in vitro verified on L. reuteri AI, chosen as probiotic candidate. Resistance to freeze-drying, production and subsequent in vivo administration evaluating strain permanence, were also performed. No loss of vitality has been recorded due to the freeze-drying process. The average value of recovery percentage of L. reuteri AI at the end of the administration period and after 1 week of follow-up was respectively 26·7 and 17·4% of the total Lactobacillus sp. CONCLUSIONS: Among several selected probiotic strains, L. reuteri AI proved to be the best probiotic candidate to use as a supplement for dogs. SIGNIFICANCE AND IMPACT OF THE STUDY: Control of intestinal pathogenic micro-organisms in dogs is a growing concern and the selection of autochthonous probiotic bacterial strains to overcome some of the gut problems associated with the modern domestication of animals is a valuable tool.


Asunto(s)
Perros/microbiología , Heces/microbiología , Lactobacillus/aislamiento & purificación , Lactobacillus/fisiología , Probióticos/aislamiento & purificación , Animales , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Ácidos y Sales Biliares/metabolismo , Fermentación , Liofilización , ARN Ribosómico 16S/genética
12.
Crit Rev Food Sci Nutr ; 58(13): 2273-2284, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28604060

RESUMEN

The remarkable growth of therapeutic peptide development in the past decade has led to a large number of market approvals and the market value is expected to hit $25 billion by 2018. This significant market increase is driven by the increasing incidences of metabolic and cardiovascular diseases and technological advancements in peptide synthesis. For this reason, the search for bioactive peptides has also increased exponentially. Many bioactive peptides from food and nonfood sources have shown positive health effects yet, obstacles such as the need to implement efficient and cost-effective strategies for industrial scale production, good manufacturing practices as well as well-designed clinical trials to provide robust evidence for supporting health claims continue to exist. Several other factors such as the possibility of allergenicity, toxicity and the stability of biological functions of the peptides during gastrointestinal digestion would need to be addressed.


Asunto(s)
Análisis de los Alimentos , Péptidos/química , Péptidos/farmacología , Biología Computacional , Descubrimiento de Drogas , Humanos
13.
Pharmacol Res ; 107: 282-290, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27038531

RESUMEN

Ruthenium compounds have become promising alternatives to platinum drugs by displaying specific activities against different cancers and favorable toxicity and clearance properties. Here, we show that the ruthenium(II) complex [Ru(p-cymene)(bis(3,5-dimethylpyrazol-1-yl)methane)Cl]Cl (UNICAM-1) exhibits potent in vivo antitumor effects. When administered as four-dose course, by repeating a single dose (52.4mgkg-1) every three days, UNICAM-1 significantly reduces the growth of A17 triple negative breast cancer cells transplanted into FVB syngeneic mice. Pharmacokinetic studies indicate that UNICAM-1 is rapidly eliminated from kidney, liver and bloodstream thanks to its high hydrosolubility, exerting excellent therapeutic activity with minimal side effects. Immunohistological analysis revealed that the efficacy of UNICAM-1, mainly relies on its capacity to reverse tumor-associated immune suppression by significantly reducing the number of tumor-infiltrating regulatory T cells. Therefore, UNICAM-1 appears very promising for the treatment of TNBC.


Asunto(s)
Antineoplásicos/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Rutenio/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Femenino , Humanos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones , Compuestos Organometálicos/sangre , Compuestos Organometálicos/farmacocinética , Compuestos Organometálicos/farmacología , Rutenio/sangre , Rutenio/farmacocinética , Rutenio/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Carga Tumoral/efectos de los fármacos
14.
J Funct Biomater ; 15(6)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38921539

RESUMEN

The objective of this work was to analyze the in vitro and in vivo tests of a novel Mg-based biodegradable alloy-Mg-0.5%Ca-with various amounts of Zn (0.5, 1, 1.5, 2.0, and 3.0 wt.%). In terms of in vitro biocompatibility, MTT and Calcein-AM cell viability assays, performed on the MG-63 cell line through the extract method, revealed that all five alloy extracts are non-cytotoxic at an extraction ratio of 0.025 g alloy per mL of cell culture medium. In the in vivo histological analysis, Mg-0.5Ca-1.5Zn demonstrated exceptional potential for stimulating bone remodeling and showed excellent biocompatibility. It was observed that Mg-0.5Ca-0.5Zn, Mg-0.5Ca-1.5Zn, and Mg-0.5Ca-3Zn displayed good biocompatibility. Furthermore, the histological examination highlighted the differentiation of periosteal cells into chondrocytes and subsequent bone tissue replacement through endochondral ossification. This process highlighted the importance of the initial implant's integrity and the role of the periosteum. In summary, Mg-0.5Ca-1.5Zn stands out as a promising candidate for bone regeneration and osseointegration, supported by both in vitro and in vivo findings.

15.
ACS Biomater Sci Eng ; 9(12): 6870-6879, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37943794

RESUMEN

Dermatomycoses are typical hair, skin, or nail infections caused mainly by dermatophytes and nondermatophytes: Trichophyton, Microsporum, Epidermophyton, and Candida. In addition to the esthetical impact, pain, and nail deformity, these mycoses can be a source of severe disease. The high cost of treatment, toxicity, and the emergence of resistant infectious agents justifies research into new drugs. This work evaluates the fungicidal activity of nanocomposites (NCs) based on reduced graphene oxide (rGO) loaded with silver (Ag) nanoparticles (rGO/Ag) against clinical isolates of dermatophytes and Candida species. This is an unprecedented study in which, for the first time, hybrid nanocompounds based on Ag/rGO were tested against Epidermophytom, Microsporum, and Trichophyton species (dermatophytes agents). In this paper, we synthesize rGO using different concentrations of Ag by hydrolysis of metal salt AgNO3 and follow the growth of nanocrystals on sheets of rGO provided by the NaBH4. The NCs were analyzed by X-ray diffraction analysis, and the NC morphology, silver distribution on the rGO surface, and crystalline information were investigated by transmission electron microscopy. Antifungal susceptibility assay was performed by the microdilution method based on modified Clinical and Laboratory Standards Institute (CLSI) protocol. Time-kill kinetics was conducted to monitor the effect of the composite to inhibit fungal cells or promote structural changes, avoiding germination. The toxicological evaluation of the NCs was born in an in vivo model based on Galleria mellonella (G. mellonella). Minimum inhibitory concentration (MIC) values of the rGO/Ag NCs ranged from 1.9 to 125 µg/mL. The best inhibitory activity was obtained for rGO/Ag12%, mainly against Candida spp. and Epidermophyton floccosum. In the presence of sorbitol, MIC values of rGO/Ag NCs were higher (ranging from 15.6 to 250 µg/mL), indicating the action mechanism on the cell wall. Both yeast and dermatophytes clinical isolates were inhibited at a minimum of 6 and 24 h, respectively, but after 2 and 12 h, they had initial antifungal interference. All hybrid formulations of rGO/Ag NCs were not toxic for G. mellonella. This study provides insights into an alternative therapeutic strategy for controlling dermatomycoses.


Asunto(s)
Arthrodermataceae , Dermatomicosis , Nanocompuestos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida , Plata/farmacología , Trichophyton , Dermatomicosis/tratamiento farmacológico
16.
J Biomed Mater Res A ; 111(8): 1264-1278, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36876550

RESUMEN

Due to the aging of population, materials able to repair damaged tissues are needed. Among others, bioactive glasses (BGs) have attracted a lot of interest due to their outstanding properties both for hard and soft tissues. Here, for the first time, two new BGs, which gave very promising results in preliminary in vitro-tests, were implanted in animals in order to evaluate their regenerative potential. The new BGs, named BGMS10 and Bio_MS and containing specific therapeutic ions, were produced in granules and implanted in rabbits' femurs for up to 60 days, to test their biocompatibility and osteoconduction. Additionally, granules of 45S5 Bioglass® were employed and used as a standard reference for comparison. The results showed that, after 30 days, the two novel BGs and 45S5 displayed a similar behavior, in terms of bone amount, thickness of new bone trabeculae and affinity index. On the contrary, after 60 days, 45S5 granules were mainly surrounded by wide and scattered bone trabeculae, separated by large amounts of soft tissue, while in BGMS10 and Bio_MS the trabeculae were thin and uniformly distributed around the BG granules. This latter scenario could be considered as more advantageous, since the features of the two novel BG granules allowed for the neo-formation of a uniformly distributed bony trabeculae, predictive of more favorable mechanical behavior, compared to the less uniform coarse trabeculae, separated by large areas of soft tissue in 45S5 granules. Thus, BGMS10 and Bio_MS could be considered suitable products for tissue regeneration in the orthopedic and dental fields.


Asunto(s)
Regeneración Ósea , Vidrio , Animales , Conejos , Huesos , Hueso Esponjoso , Fémur
17.
ALTEX ; 40(3): 389-407, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37470350

RESUMEN

The EU's chemicals regulation, REACH, requires that most chemicals in the EU be evaluated for human health and ecosystem risks, with a mandate to minimize use of animal tests for these evaluations. The REACH process has been ongoing since about 2008, but a calculation of the resulting animal use is not publicly available. For this reason, we have undertaken a count of animals used for REACH. With EU legislators set to consider REACH revisions that could expand animal testing, we are releasing results for test categories counted to date: reproductive toxicity tests, developmental toxicity tests, and repeat-ed-dose toxicity tests for human health. The total animal count as of December 2022 for these categories is about 2.9 million. Additional tests involving about 1.3 million animals are currently required by a final proposal authorization or compliance check but not yet completed. The total, 4.2 million, for just these three test categories exceeds the original European Com-mission forecast of 2.6 million for all REACH tests. The difference is primarily because the European Commission estimate excluded offspring, which are most of the animals used for REACH. Other reasons for the difference are extra animals included in tests to ensure sufficient survive to meet the minimum test requirement; dose range-finding tests; extra test animal groups, e.g., for recovery analysis; and a high rejection rate of read-across studies. Given higher than forecast animal use, the upcoming debate on proposed REACH revisions is an opportunity to refocus on reducing animal numbers in keeping with the REACH mandate.


Asunto(s)
Alternativas a las Pruebas en Animales , Ecosistema , Humanos , Animales , Alternativas a las Pruebas en Animales/métodos , Unión Europea , Medición de Riesgo/métodos , Reproducción
18.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37259386

RESUMEN

Indole-3-carbinol (I3C) is a natural product contained in vegetables belonging to the Brassicaceae family and has been studied in recent decades for its biological and pharmacological properties. Herein, we will analyze: (1) the biosynthetic processes and synthetic procedures through which I3C and its main derivatives have been obtained; (2) the characteristics that lead to believe that both I3C and its derivatives are responsible for several important activities-in particular, antitumor and antiviral, through insights concerning in vitro assays and in vivo tests; (3) the mechanisms of action of the most important compounds considered; (4) the potential social impact that the enhancement of the discussed molecules can have in the prevention and treatment of the pathologies' examined field-first of all, those related to respiratory tract disorders and cancer.

19.
Rev Alerg Mex ; 70(4): 245-249, 2023 Dec 31.
Artículo en Español | MEDLINE | ID: mdl-38506866

RESUMEN

skin tests; Sensitization; IgE-mediated allergy; allergenic extract. After the discovery of IgE, technological advances have provided new laboratory tools for the quantification of allergen-specific IgE antibodies in serum and on the surface of basophils-mast cells. In vitro testing offers numerous advantages: accurate quantitation, lack of drug interference, safety, and long-term storage of samples. Quantitative immunoassays for IgE antibodies can be an adjunct to skin testing. The allergen reagent in solid phase (allergosorbent) or liquid is the main component of the assay that confers specificity to the IgE antibody test. It is the most complex and highly variable reagent in IgE antibody assays. The choice to use diagnostic recombinants on a single rather than multiple platforms is made on a case-by-case basis (considering prior history and clinical profile) and in an allergen-dependent manner. Although most food allergies are limited to a small number of possible triggers, these foods are very complex when evaluating their allergenic potential. The possibility of fractionating the allergen and understanding some of its components as potentially important to define the risk of clinical reaction, cross-reactivity, or persistence of allergy, opened a new era in the field of allergy, called molecular allergy. The identification of the allergenic component responsible for the reactions is an important tool to confirm the information and severity of the symptoms, natural history of the disease, possibility of cross-reactivity and clinical symptoms (allergy markers).


Después del descubrimiento de la IgE, los avances tecnológicos han proporcionado nuevas herramientas de laboratorio para la cuantificación de anticuerpos IgE específicos de alérgenos en suero y en la superficie de basófilos-mastocitos. Las pruebas in vitro ofrecen numerosas ventajas: cuantificación precisa, falta de interferencia de fármacos, seguridad y almacenamiento a largo plazo de las muestras. Los inmunoensayos cuantitativos para anticuerpos IgE pueden ser un complemento de las pruebas cutáneas. El reactivo de alergeno en fase sólida (alergosorbente) o líquida es el componente principal del ensayo que confiere especificidad a la prueba de anticuerpos IgE. Es el reactivo más complejo y altamente variable en los ensayos de anticuerpos IgE. La elección de utilizar recombinantes de diagnóstico en una única plataforma en lugar de múltiples se realiza caso por caso (considerando el historial previo y el perfil clínico) y de manera dependiente de los alérgenos. Aunque la mayor parte de las alergias alimentarias se limitan a una pequeña cantidad de posibles desencadenantes, estos alimentos son muy complejos al momento de evaluar su potencial alergénico. La posibilidad de fraccionar el alérgeno y entender algunos de sus componentes como potencialmente importantes para definir el riesgo de reacción clínica, reactividad cruzada o persistencia de la alergia, abrió una nueva era en el campo de la alergia, denominada alergia molecular. La identificación del componente alergénico responsable de las reacciones supone una herramienta importante para confirmar la información y gravedad de los síntomas, historia natural de la enfermedad, posibilidad de reactividad cruzada y clínica (marcadores de alergia).


Asunto(s)
Hipersensibilidad a los Alimentos , Humanos , Hipersensibilidad a los Alimentos/diagnóstico , Alimentos , Reacciones Cruzadas , Alérgenos , Inmunoglobulina E
20.
Polymers (Basel) ; 14(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35566980

RESUMEN

Drug delivery is an important field of nanomedicine, and its aim is to deliver specific active substances to a precise site of action in order to produce a desired pharmacological effect. In the present study nanocapsules were obtained by a process of interfacial condensation between chitosan (dissolved in the aqueous phase) and poly(N-vinyl pyrrolidone-alt-itaconic anhydride), a highly reactive copolymer capable of easily opening the anhydride ring under the action of amine groups of chitosan. The formed amide bonds led to the formation of a hydrogel membrane. The morphology of the obtained nanocapsules, their behavior in aqueous solution of physiological pH, and their ability to encapsulate and release a model drug can be modulated by the parameters of the synthesis process, such as the molar ratio between functional groups of polymers and the ratio of the phases in which the polymers are solubilized. Although a priori both polymers are biocompatible, this paper reports the results of a very detailed in vivo study conducted on experimental animals which have received the obtained nanocapsules by three administration routes-intraperitoneal, subcutaneous, and oral. The organs taken from the animals' kidney, liver, spleen, and lung and analyzed histologically demonstrated the ability of nanocapsules to stimulate the monocytic macrophage system without producing inflammatory changes. Moreover, their in vivo behavior has been shown to depend not only on the route of administration but also on the interaction with the cells of the organs with which they come into contact. The results clearly argue the biocompatibility of nanocapsules and hence the possibility of their safe use in biomedical applications.

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