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1.
Neurol Sci ; 45(6): 2705-2710, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38159148

RESUMEN

BACKGROUND: The Brazilian Northeast region is notable for its high prevalence of consanguineous marriages and isolated populations, which has led to a significant prevalence of rare genetic disorders. This study describes the clinical presentation of four affected individuals from the same family, comprising two siblings and their cousins, with ages ranging from 11 to 20 years. METHODS: In a small and isolated community in Northeastern Brazil, affected individuals initially underwent a clinical assessment. Subsequently, written consent was obtained from their legal guardians, and an extensive clinical evaluation was conducted at a medical genetics center. Family data provided the basis for constructing the pedigree, and biological samples (blood or oral swabs) were collected from both affected and unaffected family members. Following informed consent from one patient, Whole Exome Sequencing (WES) was carried out, encompassing exome sequencing, assembly, genotyping, and annotation. A potentially deleterious variant was then singled out for further segregation analysis through Sanger Sequencing, involving both the proband and select family members. RESULTS AND CONCLUSION: These individuals exhibit severe neurodevelopmental delays, encompassing symptoms such as spastic paraplegia, neuropathy, intellectual impairments, and language challenges. Through next-generation sequencing (NGS) techniques, a previously unreported homozygous variant within the ERLIN2 gene linked to spastic paraplegia 18 (SPG18) was identified across all four patients. Also, all patients displayed childhood cataract, expanding the known clinical spectrum of SPG18.


Asunto(s)
Linaje , Fenotipo , Adolescente , Niño , Femenino , Humanos , Masculino , Adulto Joven , Brasil , Secuenciación del Exoma , Proteínas de la Membrana/genética , Paraplejía Espástica Hereditaria/genética
2.
Exp Parasitol ; 262: 108771, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38723847

RESUMEN

Toxoplasmosis affects about one-third of the world's population. The disease treatment methods pose several side effects and do not efficiently eliminate the parasite, making the search for new therapeutic approaches necessary. We aimed to assess the anti-Toxoplasma gondii activity of four Copaifera oleoresins (ORs) and two isolated diterpene acids, named ent-kaurenoic and ent-polyalthic acid. We used HeLa cells as an experimental model of toxoplasmosis. Uninfected and infected HeLa cells were submitted to the treatments, and the parasite intracellular proliferation, cytokine levels and ROS production were measured. Also, tachyzoites were pre-treated and the parasite invasion was determined. Finally, an in silico analysis was performed to identify potential parasite targets. Our data show that the non-cytotoxic concentrations of ORs and diterpene acids controlled the invasion and proliferation of T. gondii in HeLa cells, thus highlighting the possible direct action on parasites. In addition, some compounds tested controlled parasite proliferation in an irreversible manner. An additional and non-exclusive mechanism of action involves the modulation of host cell components, by affecting the upregulation of the IL-6. Additionally, molecular docking suggested that ent-polyalthic acid has a high affinity for the active site of the TgCDPK1 protein. Copaifera ORs have great antiparasitic activity against T. gondii, and this effect can be partially explained by the presence of the isolated compounds ent-kaurenoic and ent-polyalthic acid.


Asunto(s)
Diterpenos , Fabaceae , Extractos Vegetales , Toxoplasma , Células HeLa , Humanos , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , Diterpenos/química , Toxoplasma/efectos de los fármacos , Toxoplasma/crecimiento & desarrollo , Fabaceae/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Especies Reactivas de Oxígeno/metabolismo , Citocinas/metabolismo , Interleucina-6/metabolismo , Simulación del Acoplamiento Molecular
3.
Mutagenesis ; 38(2): 120-130, 2023 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-36738258

RESUMEN

Exposure of tobacco workers handling dried tobacco leaves has been linked to an increased risk of toxicity and respiratory illness due to the presence of nicotine and other chemicals. This study aimed to evaluate the DNA damage caused by the exposure of tobacco growers during the dry leaf classification process and the relation to cellular mechanisms. A total of 86 individuals participated in the study, divided into a group exposed to dry tobacco (n = 44) and a control group (n = 42). Genotoxicity was evaluated using the alkaline comet assay and lymphocyte micronucleus (MN) assay (CBMN-Cyt), and measurement of telomere length. The levels of oxidative and nitrosative stress were evaluated through the formation of thiobarbituric acid reactive species, and nitric oxide levels, respectively. The inorganic elements were measured in the samples using particle-induced X-ray emission method. The combination of variables was demonstrated through principal component analysis and the interactions were expanded through systems biology. Comet assay, MN, death cells, thiobarbituric acid reactive species, and nitrosative stress showed a significant increase for all exposed groups in relation to the control. Telomere length showed a significant decrease for exposed women and total exposed group in relation to men and control groups, respectively. Bromine (Br) and rubidium (Rb) in the exposed group presented higher levels than control groups. Correlations between nitrate and apoptosis; Br and MN and necrosis; and Rb and telomeres; besides age and DNA damage and death cells were observed. The systems biology analysis demonstrated that tobacco elements can increase the nuclear translocation of NFKB dimers inducing HDAC2 expression, which, associated with BRCA1 protein, can potentially repress transcription of genes that promote DNA repair. Dry tobacco workers exposed to dry leaves and their different agents showed DNA damage by different mechanisms, including redox imbalance.


Asunto(s)
Nicotiana , Exposición Profesional , Masculino , Humanos , Femenino , Nicotiana/efectos adversos , Daño del ADN , Ensayo Cometa , Exposición Profesional/efectos adversos , Pruebas de Micronúcleos/métodos , Hojas de la Planta
4.
J Med Primatol ; 52(2): 144-146, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36223274

RESUMEN

Only four of 40 animals had measurable asymmetric dimethyl arginine (ADMA) levels. The young primate had the lowest value (53.4 ng/ml) when compared with the two adults (218.8 ± 9.3 ng/ml) and the elderly one (320.5 ng/ml). The ADMA levels in this study may relate to the echocardiographic abnormalities found, and possible hypertensive individuals.


Asunto(s)
Aotidae , Arginina , Animales
5.
J Med Primatol ; 52(3): 186-189, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36945132

RESUMEN

The mean serum value of adiponectin in captive Aotus sp. is 541.99 ng/mL ± 73.05. There is no influence of sex or age, but there is a moderate positive correlation between body weight and adiponectin levels in males.


Asunto(s)
Aotidae , Fabaceae , Masculino , Animales , Adiponectina
6.
Exp Parasitol ; 250: 108534, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37100271

RESUMEN

Due to the lack of efficient antiparasitic therapy and vaccines, as well as emerging resistance strains, congenital toxoplasmosis is still a public health issue worldwide. The present study aimed to assess the effects of an oleoresin obtained from the species Copaifera trapezifolia Hayne (CTO), and an isolated molecule found in the CTO, ent-polyalthic acid (ent-15,16-epoxy-8(17),13(16),14-labdatrien-19-oic acid) (named as PA), against T. gondii infection. We used human villous explants as an experimental model of human maternal-fetal interface. Uninfected and infected villous explants were exposed to the treatments; the parasite intracellular proliferation and the cytokine levels were measured. Also, T. gondii tachyzoites were pre-treated and the parasite proliferation was determined. Our findings showed that CTO and PA reduced efficiently the parasite growth with an irreversible action, but without causing toxicity to the villi. Also, treatments reduced the levels of IL-6, IL-8, MIF and TNF by villi, what configures a valuable treatment option for the maintenance of a pregnancy in an infectious context. In addition to a possible direct effect on parasites, our data suggest an alternative mechanism by which CTO and PA alter the villous explants environment and then impair parasite growth, since the pre-treatment of villi resulted in lower parasitic infection. Here, we highlighted PA as an interesting tool for the design of new anti-T. gondii compounds.


Asunto(s)
Fabaceae , Toxoplasma , Humanos , Embarazo , Femenino , Extractos Vegetales/farmacología
7.
Mem Inst Oswaldo Cruz ; 118: e220225, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38018570

RESUMEN

BACKGROUND: Leishmaniasis, a neglected disease caused by the parasite Leishmania, is treated with drugs associated with high toxicity and limited efficacy, in addition to constant reports of the emergence of resistant parasites. In this context, snake serums emerge as good candidates since they are natural sources with the potential to yield novel drugs. OBJECTIVES: We aimed to show the antileishmanial effects of γCdcPLI, a phospholipase A2 inhibitor from Crotalus durissus collilineatus snake serum, against Leishmania (Leishmania) amazonensis. METHODS: Promastigotes forms were exposed to γCdcPLI, and we assessed the parasite viability and cell cycle, as well as invasion and proliferation assays. FINDINGS: Despite the low cytotoxicity effect on macrophages, our data indicate that γCdcPLI has a direct effect on parasites promoting an arrest in the G1 phase and reduction in the G2/M phase at the highest dose tested. Moreover, this PLA2 inhibitor reduced the parasite infectivity when promastigotes were pre-treated. Also, we demonstrated that the γCdcPLI treatment modulated the host cell environment impairing early and late steps of the parasitism. MAIN CONCLUSIONS: γCdcPLI is an interesting tool for the discovery of new essential targets on the parasite, as well as an alternative compound to improve the effectiveness of the leishmaniasis treatment.


Asunto(s)
Antiprotozoarios , Leishmania , Leishmaniasis , Animales , Humanos , Ratones , Crotalus , Leishmaniasis/tratamiento farmacológico , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Ratones Endogámicos BALB C
8.
Environ Geochem Health ; 45(10): 7081-7097, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37542205

RESUMEN

Exposure to coal mining dust poses a substantial health hazard to individuals due to the complex mixture of components released during the extraction process. This study aimed to assess the oxidative potential of residual coal mining dust on human lymphocyte DNA and telomeres and to perform a chemical characterization of coal dust and urine samples. The study included 150 individuals exposed to coal dust for over ten years, along with 120 control individuals. The results revealed significantly higher levels of DNA damage in the exposed group, as indicated by the standard comet assay, and oxidative damage, as determined by the FPG-modified comet assay. Moreover, the exposed individuals exhibited significantly shorter telomeres compared to the control group, and a significant correlation was found between telomere length and oxidative DNA damage. Using the PIXE method on urine samples, significantly higher concentrations of sodium (Na), phosphorus (P), sulfur (S), chlorine (Cl), potassium (K), iron (Fe), zinc (Zn), and bromine (Br) were observed in the exposed group compared to the control group. Furthermore, men showed shorter telomeres, greater DNA damage, and higher concentrations of nickel (Ni), calcium (Ca), and chromium (Cr) compared to exposed women. Additionally, the study characterized the particles released into the environment through GC-MS analysis, identifying several compounds, including polycyclic aromatic hydrocarbons (PAHs) such as fluoranthene, naphthalene, anthracene, 7H-benzo[c]fluorene, phenanthrene, pyrene, benz[a]anthracene, chrysene, and some alkyl derivatives. These findings underscore the significant health risks associated with exposure to coal mining dust, emphasizing the importance of further research and the implementation of regulatory measures to safeguard the health of individuals in affected populations.


Asunto(s)
Daño del ADN , Hidrocarburos Policíclicos Aromáticos , Masculino , Humanos , Femenino , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Polvo/análisis , Antracenos/análisis , Carbón Mineral/toxicidad , Carbón Mineral/análisis , Estrés Oxidativo
9.
Parasitology ; 149(2): 270-282, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35234599

RESUMEN

It was investigated how many cattle become infected with Trypanosoma vivax by subcutaneous (SC), intramuscular (IM) and intravenous (IV) routes, using the same syringe and needle from an animal with acute T. vivax infection. Besides, the T. vivax viability in 109 injectable veterinary drugs (antibiotics, antiparasitics, reproductive hormones, vitamin complex and derivatives, vaccines, anaesthetics, anti-inflammatory/antipyretics, antitoxics). In the field assay, four groups were performed: T01, T02 and T03 animals that received saline solution with the same syringe and needle contaminated with T. vivax via SC, IM and IV routes, respectively, and T04 control animals that received only saline solution with the same syringe and needle IV. In the laboratory, drugs had their pH measured and T. vivax viability verified. The number of cattle infected with T. vivax via SC (3/20) was lower (P ≤ 0.05) compared to via IM (9/20), which was lower (P ≤ 0.05) compared to IV (15/20). The solution pH did not influence T. vivax viability. In 44% (48/109) of the products, T. vivax remained viable regardless of time, stooding out that in 100% of oxytocins the protozoan was verified, at some evaluation times. The mean of T. vivax quantified in foot-and-mouth and brucellosis vaccines and in doramectin-based products were higher (P ≤ 0.05) than found in blood + saline solution.


Asunto(s)
Enfermedades de los Bovinos , Tripanosomiasis Africana , Tripanosomiasis Bovina , Animales , Bovinos , Enfermedades de los Bovinos/prevención & control , Jeringas , Trypanosoma vivax , Tripanosomiasis Africana/veterinaria
10.
Drug Dev Res ; 83(7): 1534-1554, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36042694

RESUMEN

Bacterial resistance is a problem that is giving serious cause for concern because bacterial strains such as Acinetobacter baumannii and Pseudomonas aeruginosa are difficult to treat and highly opportunistic. These bacteria easily acquire resistance genes even from other species, which confers greater persistence and tolerance towards conventional antibiotics. These bacteria have the highest death rate in hospitalized intensive care patients, so strong measures must be taken. In this review, we focus on the use of antimicrobial peptides (AMPs) as an alternative to traditional drugs, due to their rapid action and lower risk of generating resistance by microorganisms. We also present an overview of beta-lactams and explicitly explain the activity of AMPs against carbapenemase-producing bacteria as potential alternative agents for infection control.


Asunto(s)
Acinetobacter baumannii , Péptidos Antimicrobianos , Humanos , Resistencia betalactámica/genética , Acinetobacter baumannii/genética , beta-Lactamas/farmacología , Antibacterianos/farmacología , Bacterias , Pruebas de Sensibilidad Microbiana
11.
Drug Dev Res ; 83(2): 264-284, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-32045013

RESUMEN

Malaria is an infectious disease caused by protozoan parasites of the genus Plasmodium and transmitted by Anopheles spp. mosquitos. Due to the emerging resistance to currently available drugs, great efforts must be invested in discovering new molecular targets and drugs. N-myristoyltransferase (NMT) is an essential enzyme to parasites and has been validated as a chemically tractable target for the discovery of new drug candidates against malaria. In this work, 2D and 3D quantitative structure-activity relationship (QSAR) studies were conducted on a series of benzothiophene derivatives as P. falciparum NMT (PfNMT) and human NMT (HsNMT) inhibitors to shed light on the molecular requirements for inhibitor affinity and selectivity. A combination of Quantitative Structure-activity Relationship (QSAR) methods, including the hologram quantitative structure-activity relationship (HQSAR), comparative molecular field analysis (CoMFA), and comparative molecular similarity index analysis (CoMSIA) models, were used, and the impacts of the molecular alignment strategies (maximum common substructure and flexible ligand alignment) and atomic partial charge methods (Gasteiger-Hückel, MMFF94, AM1-BCC, CHELPG, and Mulliken) on the quality and reliability of the models were assessed. The best models exhibited internal consistency and could reasonably predict the inhibitory activity against both PfNMT (HQSAR: q2 /r2 /r2pred = 0.83/0.98/0.81; CoMFA: q2 /r2 /r2pred = 0.78/0.97/0.86; CoMSIA: q2 /r2 /r2pred = 0.74/0.95/0.82) and HsNMT (HQSAR: q2 /r2 /r2pred = 0.79/0.93/0.74; CoMFA: q2 /r2 /r2pred = 0.82/0.98/0.60; CoMSIA: q2 /r2 /r2pred = 0.62/0.95/0.56). The results enabled the identification of the polar interactions (electrostatic and hydrogen-bonding properties) as the major molecular features that affected the inhibitory activity and selectivity. These findings should be useful for the design of PfNMT inhibitors with high affinities and selectivities as antimalarial lead candidates.


Asunto(s)
Plasmodium falciparum , Relación Estructura-Actividad Cuantitativa , Aciltransferasas , Humanos , Reproducibilidad de los Resultados , Tiofenos
12.
World J Microbiol Biotechnol ; 38(3): 39, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35018535

RESUMEN

The emergence of multidrug-resistant bacteria, viruses and tumors is a serious threat to public health. Among natural peptides, indolicidin, a 13-residue peptide belonging to the cathelicidin family, deserves special attention. Indolicidin has a broad spectrum of biological activity and is active against a wide range of targets, such as bacteria (Gram+ and Gram-), fungi and viruses. Here, we review the most important features of the biological activity, potential applications and perspectives of indolicidin and its analogs. Although not yet approved for commercialization, this peptide has great potential to be applied in different areas, including the medical, biomedical, food industry and other unexplored areas. To achieve this goal, a multidisciplinary team of researchers must work together to fine tune peptides that overall lead to novel analogs and formulations to combat existing and possibly future diseases.


Asunto(s)
Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Animales , Péptidos Catiónicos Antimicrobianos/genética , Biopelículas/efectos de los fármacos , Catelicidinas/genética , Catelicidinas/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Relación Estructura-Actividad
13.
Med Chem Res ; 31(3): 426-435, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35106047

RESUMEN

During the last years, the progression to control malaria disease seems to be slowed and WHO (World Health Organization) reported a modeling analysis with the prediction of the increase in malaria morbidity and mortality in sub-Saharan Africa during the COVID-19 pandemic. A rapid way to the discovery of new drugs could be carried out by performing investigations to identify drugs based on repurposing of "old" drugs. The 5-nitrothiazole drug, Nitazoxanide was shown to be active against intestinal protozoa, human helminths, anaerobic bacteria, viruses, etc. In this work, Nitazoxanide and analogs were prepared using two methodologies and evaluated against P. falciparum 3D7. A bithiazole analog, showed attractive inhibitory activity with an EC50 value of 5.9 µM, low propensity to show toxic effect against HepG2 cells at 25 µM, and no cross-resistance with standard antimalarials.

14.
J Toxicol Environ Health A ; 84(8): 345-355, 2021 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-33435828

RESUMEN

Sida planicaulis is a weed thought to have originated in Brazil, where it is present in abundant quantities, but also this plant is also found in south-central Florida, Indian Ocean Islands, and the Pacific Islands. Sida planicaulis produces neurotoxicity that adversely affects livestock breeding with heavy animal losses and consequent negative impact on Brazil's economy. The aim of this study was to determine the chemical profile, cytotoxic and genotoxic effects of ethanolic extracts of S. planicaulis collected in winter (leaf extract) and summer (leaf extract and leaf + flower extract) using an in vitro model of human neuroblastoma cell line SH-SY5Y. Phytochemical screening demonstrated the presence of alkaloids, flavonoids, and apolar compounds. Rutin, quercetin, and swainsonine were detected by HPLC and GC/MS, respectively. Phosphorus, potassium, iron, and zinc were the inorganic elements found. Extracts produced cytotoxicity at all concentrations tested (7-4,000 µg/ml) as evidenced by the colorimetric assay [3-(4,5-dimethyl-thiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT)]. Based upon the alkaline comet assay extracts were found to induce genotoxicity at concentrations ranging from 0.437 to 7 µg/ml. DNA damage produced by extracts was affirmed using a modified comet assay with the enzymes Endo III and FPG in a concentration dependent manner. Further, enzyme-modified comet assay showed both oxidized purines and pyrimidines, and consequently oxidative stress was related to genomic instability and cell death. Data suggest that low concentrations of ethanolic extracts of S. planicaulis (different seasons) induced increased DNA damage related to oxidative stress and chemical composition.


Asunto(s)
Citotoxinas/farmacología , Mutágenos/farmacología , Extractos Vegetales/farmacología , Sida (Planta)/química , Línea Celular Tumoral , Citotoxinas/química , Humanos , Mutágenos/química , Extractos Vegetales/química , Estaciones del Año
15.
J Toxicol Environ Health A ; 84(17): 689-701, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34034641

RESUMEN

Nicotiana tabacum is the most cultivated tobacco species in the state of Rio Grande do Sul, Brazil. Workers who handle the plant are exposed to the leaf components during the harvesting process and when separating and classifying the dried leaves. In addition to nicotine, after the drying process, other components may be found including tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, as well as pesticides residues. The objective of this study was to examine the genotoxicity attributed to the aqueous extract of dried tobacco leaves obtained from tobacco barns using Chinese hamster lung fibroblast cells (V79) as a model system by employing alkaline comet assay, micronucleus (MN) and Ames test. MTT assay was used to assess cytotoxicity and establish concentrations for this study. Data demonstrated cell viability > 85% for concentrations of 0.625-5 mg/ml while the comet assay indicated a significant increase in DNA damage at all concentrations tested. A significant elevation of MN and nuclear buds (NBUD) was found for 5 mg/ml compared to control and other dry tobacco leaves concentrations (0.625-2.5 mg/ml). Mutagenicity was not found using the Salmonella/Microsome test (TA98, TA100, and TA102 strains) with and without metabolic activation. The concentration of inorganic elements was determined employing the PIXE technique, and 13 inorganic elements were detected. Using CG/MS nicotine amounts present were 1.56 mg/g dry tobacco leaf powder. Due to the observed genotoxicity in V79 cells, more investigations are needed to protect the health of tobacco workers exposed daily to this complex mixture of toxic substances present in dry tobacco leaves.


Asunto(s)
Mutágenos/toxicidad , Nicotiana/química , Hojas de la Planta/química , Animales , Línea Celular , Ensayo Cometa , Cricetulus , Pruebas de Micronúcleos , Pruebas de Mutagenicidad
16.
J Mater Sci Mater Med ; 32(9): 101, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34406528

RESUMEN

Nanoparticles (NPs) have a wide range of applications in various areas. For health application, cytotoxicity tests are used to ensure its efficiency and safety. In this paper, ZnFe2O4, CoFe2O4, Zn0.5Co0.5Fe2O4 NPs were synthesized, characterized and their antibacterial properties were evaluated. The Sol-Gel method was used to synthesize the NPs. Their electronic and crystallographic structures were characterized by Fourier Transform Infrared Spectroscopy Analysis (FTIR), X-ray fluorescence (XRF), X-Ray Diffraction (XRD), and Transmission Electron Microscopy (TEM). To perform the antibacterial evaluation, ferrites were dispersed through nanoemulsion to prevent the crystals from accumulating together. Then the evaluation was performed through microdilution in a 96-well plate and diffusion in agar disc in contact with 3 different strains of Staphylococcus aureus and Escherichia coli. It demonstrated that the Sol-Gel method was efficient to synthesize NPs with suitable sizes for health application. All synthesized NPs showed the inhibition of bacterias with different concentrations used.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Nanopartículas del Metal/química , Metales/química , Óxidos/química , Animales , Bacterias/efectos de los fármacos , Supervivencia Celular , Chlorocebus aethiops , Difusión , Escherichia coli , Tecnología Química Verde/métodos , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Transición de Fase , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus , Pruebas de Toxicidad , Células Vero , Difracción de Rayos X
17.
Parasitol Res ; 120(3): 1103-1108, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33491114

RESUMEN

Amitraz is an acaricide that is widely used in veterinary medicine to control the cattle tick Rhipicephalus microplus. However, controversy exists in the literature regarding the resistance of R. microplus to this product. The present work provides an update on the acaricidal efficacy of amitraz (Triatox®, 12.5 % amitraz) after 15 years without its use on a property. Two in vivo (bovines treated with amitraz and submitted to tick counts, n = 20 animals) and one in vitro (adult immersion test, n = 40 ticks) assays were performed to determine product efficacy. The efficacy of the commercial formulation tested in the first in vivo trial ranged from 14.1 to 47.0%, and in the second from 3.6 to 35.1%, for the 28 days of the experiments. Efficacy for the in vitro trial was 47.38%. The dose recommended by the manufacturer of the product did not cause mortality to most of the ticks of this strain, and efficacy/resistance was not reverted or modified after 15 years (estimated 60 tick generations).


Asunto(s)
Acaricidas/farmacología , Enfermedades de los Bovinos/tratamiento farmacológico , Rhipicephalus/efectos de los fármacos , Infestaciones por Garrapatas/veterinaria , Toluidinas/farmacología , Acaricidas/uso terapéutico , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Femenino , Larva/efectos de los fármacos , Masculino , Rhipicephalus/crecimiento & desarrollo , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/parasitología , Toluidinas/uso terapéutico
18.
J Org Chem ; 85(17): 11170-11180, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32786650

RESUMEN

This study reports a simple, reusable, and recoverable niobium-based heterogeneous catalysts for Biginelli multicomponent reactions. Different methods of catalysts preparation were investigated. For this purpose, HY-340 (Nb2O5·nH2O) and Nb2O5 were chemically and/or thermally treated and investigated as catalysts for dihydropyrimidinones (DHPMs) production. The catalysts were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, temperature-programmed desorption of NH3, adsorption/desorption of N2 at -196 °C, and thermogravimetric and differential thermal analysis. The characterization results showed that niobium oxides have the potential to be used as catalysts because of high crystallinity and large surface area. Among the tested catalysts, Nb2O5 chemically treated (Nb2O5/T) showed the best catalytic performance. In the absence of solvents, 94% yield of DHPMs was achieved. Also, Nb2O5/T can be reused three times without a significant yield decrease. Additionally, a feasible reaction pathway was suggested based on the Knoevenagel mechanism for DHPM synthesis using niobium-based catalysts.

19.
Cell Biol Int ; 44(1): 36-50, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31469205

RESUMEN

During pregnancy, the placenta regulates the transfer of oxygen, nutrients, and residual products between the maternal and fetal bloodstreams and is a key determinant of fetal exposure to xenobiotics from the mother. To study the disposition of substances through the placenta, various experimental models are used, especially the perfused placenta, placental villi explants, and cell lineage models. In this context, nanotechnology, an area of study that is on the rise, enables the creation of particles on nanometric scales capable of releasing drugs aimed at specific tissues. An important reason for furthering the studies on transplacental transfer is to explore the potential of nanoparticles (NPs), in new delivery strategies for drugs that are specifically aimed at the mother, the placenta, or the fetus and that involve less toxicity. Due to the fact that the placental barrier is essential for the interaction between the maternal and fetal organisms as well as the possibility of NPs being used in the treatment of various pathologies, the aim of this review is to present the main experimental models used in studying the maternal-fetal interaction and the action of NPs in the placental environment.

20.
Lasers Med Sci ; 35(5): 1055-1063, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31654154

RESUMEN

To investigate the effects of photobiomodulation applied to respiratory muscles on lung function, thoracoabdominal mobility, respiratory muscle strength, and functional capacity in COPD patients. This is a randomized double-blind crossover clinical trial. Twelve male COPD patients participated in the study. Participants were randomly allocated to receive two photobiomodulation sessions, 1 week apart: (1) an effective photobiomodulation session applied at the main respiratory muscles by means of a cluster with 69 light-emitting diodes (LEDs), containing 35 red (630 ± 10 nm; 10 mW; 0.2 cm2) and 34 near-infrared (830 ± 20 nm; 10 mW; 0.2 cm2) LEDs and (2) a sham photobiomodulation session, following the same procedures without emitting light. The primary outcomes were pulmonary function (spirometric indexes); thoracoabdominal mobility (cirtometry); respiratory muscle strength (maximal respiratory pressures), assessed at three moments: (1) baseline, (2) 1 h after intervention, and (3) 24 h after intervention; and the functional capacity, assessed by the 6-min walk test (6MWT) at baseline and 24 h after intervention. No significant interactions were found for spirometric variables, maximal respiratory pressures, and cirtometry. However, there was a Time × Condition interaction (F = 18.63; p = 0.001; η2p = 0.62) in the walked distance on the 6MWT, with a significant increase after photobiomodulation intervention (p < 0.01) compared with the baseline. Photobiomodulation applied to respiratory muscles was effective in improving acute functional capacity in COPD patients. To the best of our knowledge, this is the first study assessing the effects of photobiomodulation applied to respiratory muscles in patients with COPD.


Asunto(s)
Terapia por Luz de Baja Intensidad , Enfermedad Pulmonar Obstructiva Crónica/radioterapia , Músculos Respiratorios/efectos de la radiación , Anciano , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Placebos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculos Respiratorios/fisiopatología , Espirometría , Prueba de Paso
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