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1.
Nat Commun ; 12(1): 6271, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34725346

RESUMEN

Some osteoblasts embed within bone matrix, change shape, and become dendrite-bearing osteocytes. The circuitry that drives dendrite formation during "osteocytogenesis" is poorly understood. Here we show that deletion of Sp7 in osteoblasts and osteocytes causes defects in osteocyte dendrites. Profiling of Sp7 target genes and binding sites reveals unexpected repurposing of this transcription factor to drive dendrite formation. Osteocrin is a Sp7 target gene that promotes osteocyte dendrite formation and rescues defects in Sp7-deficient mice. Single-cell RNA-sequencing demonstrates defects in osteocyte maturation in the absence of Sp7. Sp7-dependent osteocyte gene networks are associated with human skeletal diseases. Moreover, humans with a SP7R316C mutation show defective osteocyte morphology. Sp7-dependent genes that mark osteocytes are enriched in neurons, highlighting shared features between osteocytic and neuronal connectivity. These findings reveal a role for Sp7 and its target gene Osteocrin in osteocytogenesis, revealing that pathways that control osteocyte development influence human bone diseases.


Asunto(s)
Enfermedades Óseas/metabolismo , Dendritas/metabolismo , Proteínas Musculares/metabolismo , Osteocitos/metabolismo , Factor de Transcripción Sp7/metabolismo , Factores de Transcripción/metabolismo , Adolescente , Animales , Enfermedades Óseas/genética , Enfermedades Óseas/fisiopatología , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Musculares/genética , Mutación , Factor de Transcripción Sp7/genética , Factores de Transcripción/genética
2.
Antimicrob Agents Chemother ; 59(8): 4782-99, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26033724

RESUMEN

The aim of the present study was to synthesize silver (Ag) and titanium dioxide (TiO2) nanoparticles (NPs) using green synthesis from aqueous leaf extract of Euphorbia prostrata as antileishmanial agents and to explore the underlying molecular mechanism of induced cell death. In vitro antileishmanial activity of synthesized NPs was tested against promastigotes of Leishmania donovani by alamarBlue and propidium iodide uptake assays. Antileishmanial activity of synthesized NPs on intracellular amastigotes was assessed by Giemsa staining. The leishmanicidal effect of synthesized Ag NPs was further confirmed by DNA fragmentation assay and by cell cycle progression and transmission electron microscopy (TEM) of the treated parasites. TEM analysis of the synthesized Ag NPs showed a spherical shape with an average size of 12.82 ± 2.50 nm, and in comparison to synthesized TiO2 NPs, synthesized Ag NPs were found to be most active against Leishmania parasites after 24 h exposure, with 50% inhibitory concentrations (IC50) of 14.94 µg/ml and 3.89 µg/ml in promastigotes and intracellular amastigotes, respectively. A significant increase in G0/G1 phase of the cell cycle with a subsequent decrease in S (synthesis) and G2/M phases compared to controls was observed. The growth-inhibitory effect of synthesized Ag NPs was attributed to increased length of S phase. A decreased reactive oxygen species level was also observed, which could be responsible for the caspase-independent shift from apoptosis (G0/G1 arrest) to massive necrosis. High-molecular-weight DNA fragmentation as a positive consequence of necrotic cell death was also visualized. We also report that the unique trypanothione/trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by synthesized Ag NPs. The green-synthesized Ag NPs may provide promising leads for the development of cost-effective and safer alternative treatment against visceral leishmaniasis.


Asunto(s)
Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Euphorbia/química , Leishmania donovani/efectos de los fármacos , Nanopartículas del Metal/administración & dosificación , Plata/farmacología , Titanio/farmacología , Antiprotozoarios/química , Antiprotozoarios/farmacología , Caspasas/metabolismo , Fase G1/efectos de los fármacos , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/metabolismo , Nanopartículas del Metal/química , Necrosis/tratamiento farmacológico , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Plata/química , Titanio/química
3.
Parasitol Res ; 114(4): 1397-406, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25653029

RESUMEN

Malaria is an infectious disease caused by the Plasmodium parasite that continues to be a health issue for humans. It is one of the most common pathogenic factors of morbidity and mortality. Palladium nanoparticles (Pd NPs) have been used as target antimicrobial compounds, as a catalyst to manufacture pharmaceuticals, degrade harmful environmental pollutants, and as sensors for the detection of various analyses. The aim of this study was to investigate the antiplasmodial activity of synthesized Pd NPs by using leaf aqueous extract of Eclipta prostrata against Plasmodium berghei in Swiss albino mice. The synthesized Pd NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Scanning electron microscopy (SEM) with Energy dispersive X-ray spectroscopy (EDX), and High-resolution transmission electron microscope (HRTEM) with the Selected area (electron) diffraction (SAED). The XRD peaks appeared at 35.61°, 44.27°, 56.40°, and 74.51°, which correspond to (111), (200), (220), and (311) planes for palladium, respectively. The FTIR spectra that were carried out to identify the potential biomolecule of synthesized Pd NPs showed the peaks at 3361, 1540, 1399, 1257, 1049, and 659 in the region of 4000-500 cm(-1). The SEM images showed aggregation of NPs with an average size of 63 ± 1.4. The HRTEM images of the precipitated solid phase obtained after termination of the reaction of E. prostrata aqueous leaf extract were in the range from 18 to 64 nm with an average size of 27 ± 1.3 nm. The in vivo antiplasmodial assay was carried out as per Peters' 4-day suppressive test, and the synthesized Pd NP-treated mice group showed reduction of parasitemia by 78.13% with an inhibitory concentration (IC)50 value of 16.44 mg/kg/body weight. The growth inhibition of E. prostrata aqueous leaf extract, palladium acetate, and synthesized Pd NPs showed the IC20, IC50, and IC90 values of 1.90, 10.29, and 64.11; 4.49, 9.84, and 23.04; and 4.34, 8.70, and 18.49 mg/kg/body weight, respectively against NK65 strain of P. berghei. In vitro cytotoxicity of the aqueous leaf extract of E. prostrata, palladium acetate, and Pd NPs that was evaluated against Hep-G2 cell lines showed the cellular toxicity of 7.5, 12, 22, 32, and 39%; 8.2, 18, 32, 55, and 66.2 %; and 8.5, 24, 48, 65, and 76.5% at 1, 10, 100, 250, and 500 µg/mL, respectively. This green chemistry approach toward the synthesis of Pd NPs has many advantages such as, ease with which the process can be scaled up, and economic viability.


Asunto(s)
Antimaláricos/administración & dosificación , Eclipta/química , Malaria/tratamiento farmacológico , Nanopartículas del Metal/química , Paladio/química , Extractos Vegetales/administración & dosificación , Plasmodium berghei/efectos de los fármacos , Animales , Antimaláricos/química , Humanos , Malaria/parasitología , Masculino , Ratones , Microscopía Electrónica de Rastreo , Extractos Vegetales/química , Hojas de la Planta/química , Espectrometría por Rayos X , Difracción de Rayos X
4.
Nanomaterials (Basel) ; 5(3): 1317-1330, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-28347066

RESUMEN

Cancer is a leading cause of death worldwide and sustained focus is on the discovery and development of newer and better tolerated anticancer drugs, especially from plants. In the present study, a simple, eco-friendly, and inexpensive approach was followed for the synthesis of zinc oxide nanoparticles (ZnO NPs) using the aqueous leaf extract of Eclipta prostrata. The synthesized ZnO NPs were characterized by UV-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), High-resolution transmission electron microscopy (HRTEM), and Selected area (electron) diffraction (SAED). The HRTEM images confirmed the presence of triangle, radial, hexagonal, rod, and rectangle, shaped with an average size of 29 ± 1.3 nm. The functional groups for synthesized ZnO NPs were 3852 cm-1 for H-H weak peak, 3138 cm-1 for aromatic C-H extend, and 1648 cm-1 for Aromatic ring stretch. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT), caspase and DNA fragmentation assays were carried out using various concentrations of ZnO NPs ranging from 1 to 100 mg/mL. The synthesized ZnO NPs showed dose dependent cytopathic effects in the Hep-G2 cell line. At 100 mg/mL concentration, the synthesized ZnO NPs exhibited significant cytotoxic effects and the apoptotic features were confirmed through caspase-3 activation and DNA fragmentation assays.

5.
Environ Sci Pollut Res Int ; 22(7): 5383-94, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25342455

RESUMEN

Applications based on silver nanoparticles (AgNPs) are limited by low temperatures, which cause aggregation of the nanoparticle fraction, leading to reduced efficacy of their products. We aimed at studying AgNP synthesis by psychrotolerant bacteria, its stability under long-term storage, and larvicidal activity under low-temperature conditions. Electron and atomic force microscopy studies revealed that 6 among 22 psychrotolerant isolates synthesized AgNPs with an average diameter of 1.9-14.1 nm. Pseudomonas mandelii SR1 synthesized the least-sized AgNPs with an average diameter of 1.9-10 nm, at temperatures as low as 12 °C without aggregate formation, and the synthesized nanoparticles were stable for up to 19 months of storage period. On studying their larvicidal activity, LC90 (lethal concentration) values against Anopheles subpictus and Culex tritaeniorhynchus larvae were at 31.7 and 35.6 mg/L, respectively. Stable non-aggregate AgNPs at low-temperature conditions from P. mandelii SR1, coupled with their larvicidal property, can be applied to control larval populations in water bodies located in seasonal or permanently cold environments.


Asunto(s)
Insecticidas/química , Insecticidas/farmacología , Nanopartículas del Metal/química , Pseudomonas/metabolismo , Plata/química , Plata/farmacología , Animales , Anopheles/efectos de los fármacos , Frío , Culex/efectos de los fármacos , Estabilidad de Medicamentos , Insecticidas/metabolismo , Larva/efectos de los fármacos , Pseudomonas/química , Plata/metabolismo
6.
Parasitol Res ; 114(2): 571-81, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25403378

RESUMEN

Titanium dioxide nanoparticles (TiO2 NPs) are considered to be among the best photocatalytic materials due to their long-term thermodynamic stability, strong oxidizing power, and relative non-toxicity. Nano-preparations with TiO2 NPs are currently under investigation as novel treatments for acne vulgaris, recurrent condyloma acuminata, atopic dermatitis, hyperpigmented skin lesions, and other non-dermatologic diseases. The present study was to investigate the acaricidal and larvicidal activity of synthesized TiO2 NPs utilizing leaf aqueous extract of Mangifera indica L. (Anacardiaceae) against hematophagous parasites. The anti-parasitic activity of TiO2 NPs against the larvae of Rhipicephalus (Boophilus) microplus, Hyalomma anatolicum anatolicum and Haemaphysalis bispinosa (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, and Culex quinquefasciatus (Diptera: Culicidae) were assessed. The green synthesized TiO2 NPs were analyzed by UV-Vis, FTIR, X-ray diffraction (XRD), AFM, SEM, and TEM. The XRD analysis of synthesized TiO2 NPs revealed the dominant peak at 2θ value of 27.81 which matched the 110 crystallographic plane of the rutile structure indicating the crystal structure. The FTIR spectra exhibited a prominent peak at 3,448 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. The SEM images of TiO2 NPs displayed spherical, oval in shape, individual, and some in aggregates. Characterization of the synthesized TiO2 NPs using AFM offered three-dimensional visualization and uneven surface morphology. The TEM micrograph showed agglomerates, round and slight elongation with an average size of 30 ± 5 nm. The maximum efficacy was observed in synthesized TiO2 NPs against the larvae of R. microplus, Hyalomma anatolicum anatolicum, Haemaphysalis bispinosa, A. subpictus, and Culex quinquefasciatus with LC50 value of 28.56, 33.17, 23.81, 5.84, and 4.34 mg/L, respectively. In the present study, a novel, simple, and eco-friendly approach has been suggested to control blood-feeding parasites.


Asunto(s)
Acaricidas/farmacología , Ixodidae/efectos de los fármacos , Mangifera/química , Extractos Vegetales/toxicidad , Titanio/química , Acaricidas/química , Animales , Anopheles/efectos de los fármacos , Anopheles/crecimiento & desarrollo , Culex/efectos de los fármacos , Culex/crecimiento & desarrollo , Evaluación Preclínica de Medicamentos , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Nanopartículas/química , Extractos Vegetales/química , Hojas de la Planta/química , Difracción de Rayos X
7.
Asian Pac J Trop Med ; 7(12): 968-76, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25479626

RESUMEN

OBJECTIVE: To determine the efficacies of antibacterial and antioxidant activities of aqueous leaf extract of Psidium guajava mediated biosynthesis of titanium dioxide nanoparticles (TiO2 NPs). METHODS: Synthesized TiO2 NPs were tested by disc diffusion method against against human pathogenic bacteria. The total antioxidant activity and phenolic content (Folin-Ciocalteau method) of synthesized TiO2 NPs and aqueous plant extract were determined. The scavenging radicals were estimated by DPPH method. The synthesized TiO2 NPs were characterized by XRD, FTIR, FESEM and EDX. RESULTS: FTIR spectra of synthesized TiO2 NPs exhibited prominent peaks at 3 410 cm(-1) (alkynes), 1 578 cm(-1), 1 451 cm(-1) (alkanes), and 1 123 cm(-1)(C-O absorption). The morphological characterization of synthesized TiO2 NPs was analysed by FESEM which showed spherical shape and clusters with an average size of 32.58 nm. The maximum zone of inhibition was observed in the synthesized TiO2 NPs (20 µg/mL) against Staphylococcus aureus (25 mm) and Escherichia coli (23 mm). The synthesized TiO2 NPs showed more antibacterial activity than the standard antibiotic disk, tetracycline which drastically reduces the chances for the development of antibiotics resistance of bacterial species. The plant aqueous extract and synthesized TiO2 NPs were found to possess maximum antioxidant activity when compared with ascorbic acid. The content of phenolic compounds (mg/g) in leaf aqueous extract and synthesized TiO2 NPs were found to be 85.4 and 18.3 mgTA/g, respectively. CONCLUSIONS: Green synthesized TiO2 NPs provides a promising approach can satisfy the requirement of large-scale industrial production bearing the advantage of low-cost, eco-friendly and reproducible.

8.
Biomed Res Int ; 2014: 915797, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24868553

RESUMEN

Many naturally occurring and synthetic compounds containing dihydrocyanopyridine and cyanopyran moiety show pharmacological properties. The aim of this study is to investigate the larvicidal and antioxidant potential of dihydrophenanthroline-3-carbonitrile derivatives 4a-f. A novel series of 2-amino-10-chloro-4,12-diphenyl-1,4,5,6-tetrahydrobenzo[j][1,7]phenanthroline-3-carbonitrile derivatives were synthesized by reacting different substituted acridine chalcones through Michel addition. The compounds were synthesized in excellent yields and the structures were corroborated on the basis of FT-IR, 1H NMR, 13C NMR, and ESI Mass analysis data. All the synthesized compounds were evaluated for larvicidal activity against Aedes aegypti and Culex quinquefasciatus larvae. Furthermore, the antioxidant activity was studied by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method. From the antioxidant assay, the compound 4c was reported with profound antioxidant potential.


Asunto(s)
Antimaláricos/química , Antioxidantes/química , Insecticidas/química , Control de Mosquitos , Nitrilos/química , Acridinas/química , Aedes , Animales , Bioensayo , Chalconas/química , Culex , Relación Dosis-Respuesta a Droga , Espectroscopía de Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray , Espectroscopía Infrarroja por Transformada de Fourier
9.
Parasitol Res ; 113(5): 1657-72, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24638906

RESUMEN

Malaria is an overwhelming impact in the poorest countries in the world due to their prevalence, virulence and drug resistance ability. Currently, there is inadequate armoury of drugs for the treatment of malaria. This underscores the continuing need for the discovery and development of new effective and safe antimalarial drugs. To evaluate the in vitro and in vivo antimalarial activity of the leaf ethyl acetate extract of Murraya koenigii, bioassay-guided chromatographic fractionation was employed for the isolation and purification of antimalarial compounds. The in vitro antimalarial activity was assayed by the erythrocytic stages of chloroquine-sensitive strain of Plasmodium falciparum (3D7) in culture using the fluorescence-based SYBR Green I assay. The in vivo assay was done by administering mice infected with Plasmodium berghei (NK65) four consecutive daily doses of the extracts through oral route following Peter's 4-day curative standard test. The percentage suppression of parasitaemia was calculated for each dose level by comparing the parasitaemia in untreated control with those of treated mice. Cytotoxicity was determined against HeLa cells using MTT assay. Histopathology was studied in kidney, liver and spleen of isolated compound-treated Swiss albino mice. The leaf crude ethyl acetate extract of M. koenigii showed good in vitro antiplasmodial activity against P. falciparum. The in vivo test of the leaf crude ethyl acetate extract (600 mg/kg) showed reduced malaria parasitaemia by 86.6% against P. berghei in mice. Bioassay-guided fractionation of the leaf ethyl acetate extract of M. koenigii led to the isolation of two purified fractions C3B2 (2.84 g) and C3B4 (1.97 g). The purified fractions C3B2 and C3B4 were found to be active with IC50 values of 10.5 ± 0.8 and 8.25 ± 0.2 µg/mL against P. falciparum, and in vivo activity significantly reduced parasitaemia by 82.6 and 88.2% at 100 mg/kg/body weight on day 4 against P. berghei, respectively. The isolated fractions C3B2 and C3B4 were monitored by thin-layer chromatography until a single spot was obtained with R f values of 0.36 and 0.52, respectively. The pure compounds obtained in the present investigation were subjected to UV-visible spectroscopy, Fourier transformer infrared spectroscopy, 1D and 2D (1)H-Nuclear magnetic resonance (NMR), (13)C NMR, DEPT, COSY and Mass spectral analysis. Based on the spectral analysis, it is concluded that the isolated compounds were myristic acid (C3B2) and ß-caryophyllene (C3B4). The cytotoxic effect of myristic acid and ß-caryophyllene showed the TC50 values of >100 and 80.5 µg/mL, respectively against HeLa cell line. The histopathology study showed that protection against nephrotoxicity of kidney, hepatic damage of liver and splenocytes protection in spleen was achieved with the highest dose tested at 100 mg/kg/body weight. The present study provides evidence of antiplasmodial compounds from M. koenigii and is reported for the first time.


Asunto(s)
Antimaláricos/farmacología , Murraya/química , Extractos Vegetales/farmacología , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/química , Femenino , Células HeLa , Humanos , Malaria/tratamiento farmacológico , Masculino , Ratones , Ácido Mirístico/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Sesquiterpenos Policíclicos , Sesquiterpenos/aislamiento & purificación
10.
Bioprocess Biosyst Eng ; 37(8): 1591-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24525832

RESUMEN

In the present study, we report rapid biological synthesis of gold nanoparticles (Au NPs) using a novel marine brown alga Ecklonia cava (Family: Lessoniaceae) by the reduction of chloroauric acid. The formation of Au NPs reaction was complete within 1 min at 80 °C and physiochemically characterized with different analytical techniques. FTIR spectroscopy revealed that Au NPs were functionalized with biomolecules that have primary amine group, hydroxyl group and other stabilizing functional groups. X-ray diffraction pattern showed high purity and face-centered cubic structure of Au NPs. Microscopy results showed that these Au NPs are formed with shapes like spherical and triangular with an average size of 30 ± 0.25 nm. Synthesized Au NPs showed good antimicrobial and biocompatibility with human keratinocyte cell line. Thus, physiochemical characteristic results suggest that Au NPs will have promising biomedical applications in different area such as drug delivery, tissue engineering, biosensor, etc.


Asunto(s)
Cloruros/química , Compuestos de Oro/química , Oro/química , Nanopartículas del Metal/química , Humanos , Oxidación-Reducción , Tamaño de la Partícula , Phaeophyceae
11.
Parasitol Res ; 113(2): 469-79, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24265057

RESUMEN

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in paints, printing ink, rubber, paper, cosmetics, sunscreens, car materials, cleaning air products, industrial photocatalytic processes, and decomposing organic matters in wastewater due to their unique physical, chemical, and biological properties. The present study was conducted to assess the antiparasitic efficacies of synthesized TiO2 NPs utilizing leaf aqueous extract of Solanum trilobatum against the adult head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae); larvae of cattle tick Hyalomma anatolicum (a.) anatolicum Koch (Acari: Ixodidae), and fourth instar larvae of malaria vector Anopheles subpictus Grassi (Diptera: Culicidae). The green synthesized TiO2 NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy analysis (EDX), and Atomic force microscopy (AFM). XRD analysis of synthesized TiO2 NPs revealed that the particles were in the form of nanocrystals as evidenced by the major peaks at 2θ values of 27.52°, 36.21°, and 54.43° identified as 110, 101, and 211 reflections, respectively. FTIR spectra exhibited a prominent peak at 3,466 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. SEM images displayed NPs that were spherical, oval in shape, individual, and some in aggregates with an average size of 70 nm. Characterization of the synthesized TiO2 NPs using AFM offered a three-dimensional visualization and uneven surface morphology. The pediculocidal and acaricidal activities of synthesized TiO2 NPs showed the percent mortality of 31, 42, 63, 82, 100; 36, 44, 67, 89, and 100 at 2, 4, 6, 8, and 10 mg/L, respectively, against P. h. capitis and H. a. anatolicum. The average larval percent mortality of synthesized TiO2 NPs was 38, 47, 66, 79, and 100 at 1, 2, 3, 4, and 5 mg/L, respectively, against A. subpictus. The maximum activity was observed in the aqueous leaf extract of S. trilobatum, TiO(OH)2 solutions (bulk), and synthesized TiO2 NPs with LC50 values of 35.14, 25.85, and 4.34 mg/L; 47.15, 29.78, and 4.11 mg/L; and 28.80, 24.01, and 1.94 mg/L, and r (2) values of 0.982, 0.991, and 0.992; 0.947, 0.987, and 0.997; and 0.965, 0.998 and 0.985, respectively, against P. h. capitis, H. a. anatolicum, and A. subpictus. This study provides the first report on the pediculocidal, acaricidal, and larvicidal activity of synthesized TiO2 NPs. This is an ideal eco-friendly, novel, low-cost, and simple approach to satisfy the requirement of large-scale industrial production bearing the advantage for the control of P. h. capitis, H. a. anatolicum, and A. subpictus.


Asunto(s)
Anopheles/efectos de los fármacos , Ixodidae/efectos de los fármacos , Nanopartículas del Metal , Pediculus/efectos de los fármacos , Extractos Vegetales/metabolismo , Solanum/química , Titanio/farmacología , Acaricidas/farmacología , Animales , Bovinos , Humanos , Insecticidas/farmacología , Larva/efectos de los fármacos , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Rastreo , Pruebas de Sensibilidad Parasitaria , Hojas de la Planta/química , Espectrometría por Rayos X , Difracción de Rayos X
12.
Parasitol Res ; 112(11): 3951-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24013340

RESUMEN

A novel approach to control strategies for integrated blood-feeding parasite management is in high demand, including the use of biological control agents. The present study aims to determine the efficacy of optimized crude extract of actinomycetes strain LK1 as biological control agent against the fourth-instar larvae of Anopheles stephensi and Culex tritaeniorhynchus (Diptera: Culicidae) and adults of Haemaphysalis bispinosa, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae), and Hippobosca maculata (Diptera: Hippoboscidae). Antiparasitic activity was optimized using the Plackett-Burman method, and the design was developed using the software Design-Expert version 8.0.7.1. The production of the optimized crude actinomycetes LK1 strain extract was performed using response surface methodology to optimize the process parameters of protease inhibitor activity of marine actinobacteria for the independent variables like pH, temperature, glucose, casein, and NaCl at two levels (-1 and +1). The potential actinomycetes strain was identified as Saccharomonas spp., and the metamodeling surface simulation procedure was followed. It was studied using a computer-generated experimental design, automatic control of simulation experiments, and sequential optimization of the metamodels fitted to a simulation response surface function. The central composite design (CCD) used for the analysis of treatment showed that a second-order polynomial regression model was in good agreement with the experimental results at R (2) = 0.9829 (p < 0.05). The optimized values of the variables for antioxidant production were pH 6.00, glucose 1.3%, casein 0.09%, temperature 31.23 °C, and NaCl 0.10%. The LK1 strain-optimized crude extract was purified using reversed-phase high-pressure liquid chromatography, and the isolated protease inhibitor showed antiparasitic activity. The antiparasitic activity of optimized crude extract of LK1 was tested against larvae of A. stephensi (LC50 = 31.82 ppm; r(2) = 0.818) and C. tritaeniorhynchus (LC50 = 26.62 ppm; r(2) = 0.790) and adults of H. bispinosa (LC50 = 106.58 ppm; r(2) = 0.871), R. (B.) microplus (LC50 = 92.96 ppm; r(2) = 0.913), and H. maculata (LC50 = 84.90 ppm; r(2) = 0.857).


Asunto(s)
Actinobacteria/aislamiento & purificación , Actinobacteria/fisiología , Antibiosis , Dípteros/microbiología , Ixodidae/microbiología , Control Biológico de Vectores/métodos , Actinobacteria/química , Animales , Organismos Acuáticos/crecimiento & desarrollo , Organismos Acuáticos/aislamiento & purificación , Dípteros/fisiología , Insecticidas/aislamiento & purificación , Insecticidas/farmacología , Ixodidae/fisiología , Inhibidores de Proteasas/aislamiento & purificación , Inhibidores de Proteasas/farmacología , Análisis de Supervivencia
13.
Parasitol Res ; 112(12): 4105-12, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24013343

RESUMEN

The developments of resistance and persistence to chemical insecticides and concerns about the non-target effects have prompted the development of eco-friendly mosquito control agents. The aim of this study was to investigate the larvicidal activities of synthesized cobalt nanoparticles (Co NPs) using bio control agent, Bacillus thuringiensis against malaria vector, Anopheles subpictus and dengue vector, Aedes aegypti (Diptera: Culicidae). The synthesized Co NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy, and Transmission electron microscopy (TEM). XRD analysis showed three distinct diffraction peaks at 27.03°, 31.00°, and 45.58° indexed to the planes 102, 122, and 024, respectively on the face-centered cubic cobalt acetate with an average size of 85.3 nm. FTIR spectra implicated role of the peak at 3,436 cm(-1) for O-H hydroxyl group, 2924 cm(-1) for methylene C-H stretch in the formation of Co NPs. FESEM analysis showed the topological and morphological appearance of NPs which were found to be spherical and oval in shape. TEM analysis showed polydispersed and clustered NPs with an average size of 84.81 nm. The maximum larvicidal mortality was observed in the cobalt acetate solution, B. thuringiensis formulation, and synthesized Co NPs against fourth instar larvae of A. subpictus and A. aegypti with LC50 values of 29.16, 8.12, 3.59 mg/L; 34.61, 6.94, and 2.87 mg/L; r (2) values of 0.986, 0.933, 0.942; 0.962, 0.957, and 0.922, respectively.


Asunto(s)
Bacillus thuringiensis/metabolismo , Cobalto/química , Insecticidas/química , Nanopartículas del Metal/química , Control de Mosquitos , Aedes , Animales , Anopheles , Cobalto/farmacología , Culicidae/efectos de los fármacos , Insectos Vectores/efectos de los fármacos , Insecticidas/farmacología , Larva/efectos de los fármacos
14.
Asian Pac J Trop Med ; 6(9): 682-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23827143

RESUMEN

OBJECTIVE: To assess the acaricidal activity of titanium dioxide nanoparticles (TiO2 NPs) synthesized from flower aqueous extract of Calotropis gigantea(C. gigantea) against the larvae of Rhipicephalus (Boophilus) microplus [R. (B.) microplus] and the adult of Haemaphysalis bispinosa (H. bispinosa). METHODS: The lyophilized C. gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO(OH)2 (10 mM) and magnetically stirred for 6 h. Synthesized TiO2 NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive X-ray spectroscopy (EDX). The synthesised TiO2 NPs were tested against the larvae of R. (B.) microplus and adult of H. bispinosa were exposed to filter paper impregnated method. RESULTS: XRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm. The functional groups for synthesized TiO2 NPs were 1 405.19, and 1 053.45 cm(-1) for -NH2 bending, primary amines and amides and 1 053.84 and 1 078.45 cm(-1) for C-O. SEM micrographs of the synthesized TiO2 NPs showed the aggregated and spherical in shape. The maximum efficacy was observed in the aqueous flower extract of C. gigantea and synthesized TiO2 NPs against R. (B.) microplus (LC50=24.63 and 5.43 mg/L and r(2)=0.960 and 0.988) and against H. bispinosa (LC50= 35.22 and 9.15 mg/L and r(2) = 0.969 and 0.969), respectively. CONCLUSIONS: The synthesized TiO2 NPs were highly stable and had significant acaricidal activity against the larvae of R. (B.) microplus and adult of H. bispinosa. This study provides the first report of synthesized TiO2 NPs and possessed excellent anti-parasitic activity.


Asunto(s)
Acaricidas/farmacología , Calotropis/química , Ixodidae/efectos de los fármacos , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Rhipicephalus/efectos de los fármacos , Titanio/farmacología , Acaricidas/síntesis química , Acaricidas/química , Animales , Femenino , Flores/química , Ixodidae/crecimiento & desarrollo , Masculino , Tamaño de la Partícula , Extractos Vegetales/química , Rhipicephalus/crecimiento & desarrollo , Titanio/química
15.
Exp Parasitol ; 134(1): 26-32, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23399920

RESUMEN

Malaria caused by the protozoan parasite Plasmodium falciparum, is a major health problem of the developing world. In the present study medicinal plants from Eastern Ghats of South India have been extracted with ethyl acetate and assayed for growth inhibition of asexual erythrocytic stages of chloroquine (CQ)-sensitive (3D7) and (CQ)-resistant (INDO) strains of P. falciparum in culture using the fluorescence-based SYBR Green I assay. Studied extracts showed a spectrum of antiplasmodial activities ranging from (a) very good (IC(50)<10-10 µg/mL: Cyperus rotundus and Zingiber officinale); (b) good (IC(50), >10-15 µg/mL: Ficus religiosa and Murraya koenigii); (c) moderate (IC(50)>15-25 µg/mL: Ficus benghalensis); (d) poor activity (IC(50)>25-60 µg/mL) and (e) inactive (IC(50)>60 µg/mL). Resistance indices ranging from 0.78 to 1.28 suggest that some of these extracts had equal promise against the CQ resistant INDO strain of P. falciparum. Cytotoxicity assessment of the extracts against HeLa cell line using MTT assay revealed that the selectivity indices in the range of 3-15 suggesting a good margin of safety.


Asunto(s)
Extractos Vegetales/farmacología , Plantas Medicinales/química , Plasmodium falciparum/efectos de los fármacos , Cyperus/química , Resistencia a Medicamentos , Ficus/química , Zingiber officinale/química , Células HeLa/efectos de los fármacos , Humanos , India , Concentración 50 Inhibidora , Murraya/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad
16.
Artículo en Inglés | MEDLINE | ID: mdl-23416912

RESUMEN

Nanosized materials have been an important subject in basic and applied sciences. A novel, low-cost, green and reproducible bacteria, Aeromonas hydrophila mediated biosynthesis of titanium dioxide nanoparticles (TiO2 NPs) was reported. The resulting nanoparticles were characterized by FTIR, XRD, AFM and FESEM with EDX. FTIR showed characteristic bands (1643 and 3430 cm(-1)) finds the role of carboxyl group OH stretching amine NH stretch in the formation of TiO2 NPs. The XRD spectrum confirmed that the synthesized TiO2 NPs were in the form of nanocrystals, as evidenced by the peaks at 2θ values of 27.47°, 31.77°, 36.11°, 41.25°, 54.39°, 56.64° and 69.54° were identified as 110, 100, 101, 111, 211, 220 and 301 reflections, respectively. The crystallite sizes were calculated using Scherrer's formula applied to the major intense peaks and found to be the size of 40.50 nm. The morphological characterization was analyzed by FESEM and the analysis showed the NPs smooth shaped, spherical and uneven. GC-MS analysis showed the main compounds found in A. hydrophila were uric acid (2.95%), glycyl-L-glutamic acid (6.90%), glycyl-L-proline (74.41%) and L-Leucyl-D-leucine (15.74%). The potential glycyl-L-proline could have played an important role as a capping agent. A possible mechanism for the biosynthesis of TiO2 NPs has been proposed. The antibacterial activity of the synthesized TiO2 NPs was assessed by well diffusion method toward A. hydrophila, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis and showed effective inhibitory activity against S. aureus (33 mm) and S. pyogenes (31 mm).


Asunto(s)
Aeromonas hydrophila/química , Antibacterianos/química , Antibacterianos/farmacología , Tecnología Química Verde/métodos , Nanopartículas/química , Titanio/química , Titanio/farmacología , Aeromonas hydrophila/metabolismo , Antibacterianos/metabolismo , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Dipéptidos/química , Dipéptidos/metabolismo , Humanos , Nanopartículas/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Titanio/metabolismo , Difracción de Rayos X
17.
Asian Pac J Trop Med ; 6(2): 95-101, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23339909

RESUMEN

OBJECTIVE: To investigate the larvicidal activity of synthesized silver nanoparticles (Ag NPs) utilizing aqueous bark extract of Ficus racemosa (F. racemosa) was tested against fourth instar larvae of filariasis vector, Culex quinquefasciatus (Cx. quinquefasciatus) and japanese encephalitis vectors, Culex gelidus (Cx. gelidus). METHODS: The synthesized Ag NPs was characterized by UV-vis spectrum, X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). The larvicidal activities were assessed for 24 h against the larvae of Cx. quinquefasciatus and Cx. gelidus with varying concentrations of aqueous bark extract of F. racemosa and synthesized Ag NPs. LC(50) and r(2) values were calculated. RESULTS: The maximum efficacy was observed in crude aqueous extract of F. racemosa against the larvae of Cx. quinquefasciatus and Cx. gelidus (LC(50)=67.72 and 63.70 mg/L; r(2)=0.995 and 0.985) and the synthesized Ag NPs (LC(50)=12.00 and 11.21 mg/L; r(2)=0.997 and 0.990), respectively. Synthesized Ag NPs showed the XRD peaks at 2 θ values of 27.61, 29.60, 35.48, 43.48 and 79.68 were identified as (210), (121), (220), (200) and (311) reflections, respectively. The FTIR spectra of Ag NPs exhibited prominent peaks at 3,425, 2,878, 1,627 and 1,382 in the region 500-3,000 cm(-1). The peaks correspond to the presence of a stretching vibration of (NH) C=O group. SEM analysis showed shape in cylindrical, uniform and rod with the average size of 250.60 nm. CONCLUSIONS: The biosynthesis of silver nanoparticles using bark aqueous extract of F. racemosa and its larvicidal activity against the larvae of disease spreading vectors. The maximum larvicidal efficacy was observed in the synthesized Ag NPs.


Asunto(s)
Culex/efectos de los fármacos , Ficus/química , Insecticidas/farmacología , Nanopartículas del Metal/administración & dosificación , Extractos Vegetales/farmacología , Plata/farmacología , Animales , Tecnología Química Verde , Insecticidas/síntesis química , Insecticidas/química , Larva/efectos de los fármacos , Nanopartículas del Metal/química , Corteza de la Planta/química , Extractos Vegetales/química , Plata/química , Análisis Espectral
18.
Vet Parasitol ; 191(3-4): 332-9, 2013 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-23040768

RESUMEN

The present study was on assessment of the anti-parasitic activities of nickel nanoparticles (Ni NPs) against the larvae of cattle ticks Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum (a.) anatolicum (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, Culex quinquefasciatus and Culex gelidus (Diptera: Culicidae). The metallic Ni NPs were synthesized by polyol process from Ni-hydrazine as precursor and Tween 80 as both the medium and the stabilizing reagent. The synthesized Ni NPs were characterized by Fourier transform infrared (FTIR) spectroscopy analysis which indicated the presence of Ni NPs. Synthesized Ni NPs showed the X-ray diffraction (XRD) peaks at 42.76°, 53.40°, and 76.44°, identified as 111, 220, and 200 reflections, respectively. Scanning electron microscopy (SEM) analysis of the synthesized Ni NPs clearly showed that the Ni NPs were spherical in shape with an average size of 150 nm. The Ni NPs showed maximum activity against the larvae of R. (B.) microplus, H. a. anatolicum, A. subpictus, C. quinquefasciatus and C. gelidus with LC(50) values of 10.17, 10.81, 4.93, 5.56 and 4.94 mg/L; r(2) values of 0.990, 0.993, 0.992, 0.950 and 0.988 and the efficacy of Ni-hydrazine complexes showed the LC(50) values of 20.35, 22.72, 8.29, 9.69 and 7.83 mg/L; r(2) values of 0.988, 0.986, 0.989, 0.944 and 0.978, respectively. The findings revealed that synthesized Ni NPs possess excellent larvicidal parasitic activity. To the best of our knowledge, this is the first report on larvicidal activity of blood feeding parasites using synthesized Ni NPs.


Asunto(s)
Antiparasitarios/farmacología , Culicidae/efectos de los fármacos , Ixodidae/efectos de los fármacos , Nanopartículas del Metal , Níquel/farmacología , Animales , Larva/efectos de los fármacos , Nanopartículas del Metal/química , Espectroscopía Infrarroja por Transformada de Fourier
19.
Parasitol Res ; 112(2): 719-29, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23180127

RESUMEN

Ticks and mosquitoes are ectoparasitic arthropods that can transmit a variety of diseases to humans and animals during blood feeding and causing serious infectious disorders. The purpose of the present study was to assess the acaricidal and insecticidal property of ethyl acetate extract and its compounds isolated from marine actinobacteria, Streptomyces VITSTK7 sp. against the larvae of cattle ticks, Haemaphysalis bispinosa and Rhipicephalus (Boophilus) microplus (Acari: Ixodidae); fourth-instar larvae of malaria vector, Anopheles subpictus; and filarial vector, Culex quinquefasciatus (Diptera: Culicidae). The ethyl acetate extract was loaded on silica gel column and separated with chloroform, methanol, and acetone as the solvents system. The separation of fractions was visualized by the thin layer chromatography (TLC) plate, further confirmed by high-performance liquid chromatography, and followed by gas liquid chromatography. Three major fractions were analyzed in mass spectroscopy (MS) and matched with existing compounds in the data base. Based on the fragment pattern, it led to the major compounds which were predicted as cyclopentanepropanoic acid, 3,5-bis(acetyloxy)-2-[3-(methoxyimino)octyl], methyl ester (13.3 %) 1; 5-azidomethyl-3-(2-ethoxy carbonyl-ethyl)-4-ethoxycarbonylmethyl-1H-pyrrole-2-carboxylic acid, ethyl ester (18.2 %) 2; and akuammilan-16-carboxylic acid, 17-(acetyloxy)-10-methoxy, methyl ester (16R) (53.3 %) 3. The maximum efficacy was observed in compounds 1, 2, and 3, and the ethyl acetate extract of Streptomyces VITSTK7 sp. against the larvae of H. bispinosa (LC(50) = 1,573.36, 1,333.09, 1,073.29, and 409.71 ppm; r(2) = 0.0.990, 0.934, 0.935, and 0.908), R. microplus (LC(50) = 1,877.86, 815.83, 1,631.14, and 441.54 ppm; r(2) = 0.981, 0.926, 0.0970, and 0.915), A. subpictus (LC(50) = 273.89, 687.69, 464.75, and 223.83 ppm; r(2) = 0.758, 0.924, 0.841, and 0.902), and C. quinquefasciatus (LC(50) = 430.06, 881.59, 777.0, and 195.70 ppm; r(2) = 0.839, 0.859, 0.870, and 0.882), respectively. Results of the present study provide evidence that the maximum parasitic activity of ethyl acetate extract and a synergistic effect of combinations of different compounds have been suggested. The control (distilled water) showed nil mortality in the concurrent assay. In the present study, a novel, targeted, simple, and eco-friendly approach has been suggested to control blood-feeding parasites.


Asunto(s)
Acaricidas/farmacología , Anopheles/efectos de los fármacos , Productos Biológicos/farmacología , Culex/efectos de los fármacos , Insecticidas/farmacología , Ixodidae/efectos de los fármacos , Streptomyces/química , Acaricidas/química , Acaricidas/aislamiento & purificación , Animales , Bioensayo , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Cromatografía , Insecticidas/química , Insecticidas/aislamiento & purificación , Larva/efectos de los fármacos , Espectrometría de Masas , Streptomyces/aislamiento & purificación , Análisis de Supervivencia , Microbiología del Agua
20.
Parasitol Res ; 112(1): 215-26, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22009268

RESUMEN

The aim of the present study was to assess the larvicidal property of marine actinobacterial compound 5-(2,4-dimethylbenzyl) pyrrolidin-2-one (DMBPO) extracted and isolated from Streptomyces VITSVK5 sp. tested against the larvae of Rhipicephalus (Boophilus) microplus Canestrini (Acari: Ixodidae), Anopheles stephensi Liston, and Culex tritaeniorhynchus Giles (Diptera: Culicidae). The isolate bacteria was taxonomically characterized, identified, and designated as Streptomyces VITSVK5 sp. The crude extract was loaded on silica gel column and eluted with chloroform:methanol. The isolated pure compound was analyzed by thin layer chromatography using chloroform and methanol as the solvent system and confirmed by high-performance liquid chromatography. The structure of the purified compound was established from infrared, ultraviolet, (1)H-nuclear magnetic resonance (NMR), (13)C-NMR, and mass spectral data. The chemical shift assignments obtained for the aliphatic compound from (1)H-NMR corresponding to the molecular formula C(13)H(17)NO. Bioassay-guided fractionation led to the isolation of compound which was identified as DMBPO. In the present study, Streptomyces VITSVK5 sp. crude extract and different fractions were tested against the larvae of parasites at the concentration of 1,000 ppm. Those fractions showing 100% mortality in 24 h alone was selected for further column chromatographic separation. The purified compound, C(13)H(17)NO, was tested in the concentrations of 500, 250, 125, 62.5, and 31.25 ppm and observed the percent larval mortality of 100, 70, 64, 40, and 28 against R. microplus; 100, 79, 63, 36, and 22 against A. stephensi; and 100, 84, 67, 42, and 27 against C. tritaeniorhynchus, respectively. The crude extract showed parasitic effects after 24 h of exposure at 1,000 ppm, and parasite mortality was observed against the larvae of R. microplus (LC(50) = 210.39 ppm, r (2) = 0.873); A. stephensi (LC(50) = 169.38 ppm, r (2) = 0.840); and C. tritaeniorhynchus (LC(50) = 198.75 ppm, r (2) = 0.887). The maximum efficacy was observed in purified marine actinobacterial compound DMBPO with LC(50) and r (2) values against the larvae of R. microplus (84.31 ppm, 0.889); A. stephensi (88.97 ppm, 0.817), and C. tritaeniorhynchus (74.95 ppm, 0.781), respectively. The control (distilled water) showed nil mortality in the concurrent assay.


Asunto(s)
Anopheles/efectos de los fármacos , Culex/efectos de los fármacos , Insecticidas/farmacología , Pirrolidinonas/farmacología , Rhipicephalus/efectos de los fármacos , Streptomyces/química , Animales , Cromatografía en Capa Delgada , Insecticidas/química , Insecticidas/aislamiento & purificación , Larva/efectos de los fármacos , Estructura Molecular , Pirrolidinonas/química , Pirrolidinonas/aislamiento & purificación , Análisis Espectral , Streptomyces/clasificación , Streptomyces/aislamiento & purificación , Análisis de Supervivencia
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