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1.
Phys Rev Lett ; 131(6): 067001, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37625056

RESUMO

With artificially engineered systems, it is now possible to realize the coherent interaction rate, which can become comparable to the mode frequencies, a regime known as ultrastrong coupling (USC). We experimentally realize a cavity-electromechanical device using a superconducting waveguide cavity and a mechanical resonator. In the presence of a strong pump, the mechanical-polaritons splitting can nearly reach 81% of the mechanical frequency, overwhelming all the dissipation rates. Approaching the USC limit, the steady-state response becomes unstable. We systematically measure the boundary of the unstable response while varying the pump parameters. The unstable dynamics display rich phases, such as self-induced oscillations, period-doubling bifurcation, and period-tripling oscillations, ultimately leading to the chaotic behavior. The experimental results and their theoretical modeling suggest the importance of residual nonlinear interaction terms in the weak-dissipative regime.

2.
J Clin Transl Res ; 8(1): 54-60, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35187290

RESUMO

BACKGROUND AND AIM: Advanced epithelial ovarian cancer (OC) has a high disease manifestation with difficult-to-manage symptoms that limit the patients' functionality. Abdominal pain, persistent back pain, and neuropathic pain are among the common discomforts associated with OC and its treatment. Our study aims to determine pain scores in advanced OC patients undergoing surgery and chemotherapeutic treatment with carboplatin and paclitaxel. METHODS: One hundred and ten patients with advanced epithelial OC were enrolled and treated with surgery and an adjuvant/neoadjuvant chemotherapy regimen of carboplatin-paclitaxel for six cycles (triweekly). Pain intensity was analyzed using the validated numerical rating scale for resting, movement, sleep interference-associated pain, and neuropathic pain scores were evaluated using the neuropathic pain symptom inventory scale. Pain was correlated with Qol according to Fact-O questionnaires. Chemo-response was evaluated using the CA125 blood biomarker and CT scan of the abdomen and thorax. Data were recorded at baseline, 2, 4, and 6 months of the six chemotherapy cycles. RESULTS: Of the 110 patients, no statistically significant differences were found in pain at baseline and after treatment (P > 0.05) and between the responder and non-responder categories (P > 0.05). However, movement-associated pain had a significant correlation with chemo-response and a strong positive correlation with the patients' physical and functional wellbeing. There were more chemo-induced neuropathy occurrences (P = 0.001) in the neoadjuvant chemotherapy group. CONCLUSION: Patients in the neoadjuvant chemotherapy arm experienced more chemo-induced neuropathy that was persistent and did not improve with the treatment. RELEVANCE FOR PATIENTS: Peripheral neuropathy is a common adverse effect of platinum and taxane chemotherapeutic drugs that persists throughout cancer treatment and in survivorship. This research provides evidence that chemotherapy-associated neuropathy affects Qol of patients and it will be helpful to improve pain and palliative care management policies.

3.
Support Care Cancer ; 30(4): 3371-3378, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34988703

RESUMO

PURPOSE: The study aims to record the quality of life (Qol) and its changes while ovarian cancer (OC) patients undergo debulking surgeries and chemotherapy in a tertiary care hospital of Eastern India. METHODS: Patients with advanced epithelial OC (FIGO stages III-IV) were recruited. They underwent primary/interval debulking surgeries with classical chemotherapy (adjuvant/neoadjuvant) of intravenous tri-weekly doses of paclitaxel + carboplatin. QoL was assessed using Fact- O + FACIT-Sp-12 questionnaire with a set of 51 questions in different domains (spiritual, physical, social, emotional, and functional factors) and a special set for OC patients under the heading "Additional concerns." The responses from patients were recorded at baseline (diagnosis/study entry), 2, 4, and 6 months during the treatment visits. Overall survival (OS) was assessed using Kaplan Meier curve. RESULTS: A majority of patients were 49.15±10.8 years of age, school-educated (54%), unemployed/homemakers (73.5%), belonging from rural setup (64.6%) with a monthly income of Rs. 2000/- to Rs. 5000/-. There was no statistically significant (p>0.05) improvement found in Qol from the baseline till the end of the study, neither overall nor in subsets (responders (Rs)/partial responders (PRs)/non-responder (NRs) groups or the adjuvant and neoadjuvant chemotherapy groups). The common toxicities like anemia, constipation, and weight loss were significantly (p<0.05) correlated with the patients' physical, functional, emotional, and social well-being. CONCLUSION: Ovarian cancer patients represent a poor functional, social, and disease-specific quality of life that needs to be addressed, identified, and improved by the growing nexus of healthcare providers and researchers.


Assuntos
Neoplasias Ovarianas , Qualidade de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina , Carcinoma Epitelial do Ovário/tratamento farmacológico , Quimioterapia Adjuvante , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Paclitaxel , Centros de Atenção Terciária
4.
Chromosome Res ; 29(2): 131-144, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33409811

RESUMO

Loss of mitosis regulation is a common feature of malignant cells that leads to aberrant cell division with inaccurate chromosome segregation. The mitotic checkpoint is responsible for faithful transmission of genetic material to the progeny. Defects in this checkpoint, such as mutations and changes in gene expression, lead to abnormal chromosome content or aneuploidy that may facilitate cancer development. Furthermore, a defective checkpoint response is indicated in the development of drug resistance to microtubule poisons that are used in treatment of various blood and solid cancers for several decades. Mitotic slippage and senescence are important cell fates that occur even with an active mitotic checkpoint and are held responsible for the resistance. However, contradictory findings in both the scenarios of carcinogenesis and drug resistance have aroused questions on whether mitotic checkpoint defects are truly responsible for these dismal outcomes. Here, we discuss the possible contribution of the faulty checkpoint signaling in cancer development and drug resistance, followed by the latest research on this pathway for better outcomes in cancer treatment.


Assuntos
Pontos de Checagem da Fase M do Ciclo Celular , Neoplasias , Segregação de Cromossomos , Resistência a Medicamentos , Humanos , Mitose , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fuso Acromático
5.
Nanomedicine ; 20: 102006, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31059793

RESUMO

Corticosteroids commonly prescribed in asthma show several side-effects. Relatively non-toxic andrographolide (AG) has an anti-asthmatic potential. But its poor bioavailability and short plasma half-life constrain its efficacy. To overcome them, we encapsulated AG in nanoparticle (AGNP) and evaluated AGNP for anti-asthmatic efficacy on murine asthma model by oral/pulmonary delivery. AGNP had 5.47% drug loading with a sustained drug release in vitro. Plasma and lung pharmacokinetic data showed predominantly improved AG-bioavailability upon AGNP administered orally/by pulmonary route. Cell numbers, IL-4, IL-5, and IL-13 levels in broncho-alveolar lavage fluid and serum IgE content were reduced significantly after administration of AGNP compared to free-AG treatment. AGNP-mediated suppression of NF-κß was predominantly more compared to free-AG. Further, pulmonary route showed better therapeutic performance. In conclusion, AGNP effectively controlled mild and severe asthma and the pulmonary administration of AGNP was more efficacious than the oral route.


Assuntos
Asma/tratamento farmacológico , Diterpenos/uso terapêutico , Nanopartículas/química , Animais , Asma/sangue , Asma/complicações , Asma/patologia , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Modelos Animais de Doenças , Diterpenos/sangue , Diterpenos/farmacocinética , Diterpenos/farmacologia , Liberação Controlada de Fármacos , Hipersensibilidade/complicações , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/patologia , Imunoglobulina E/sangue , Inflamação/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Nanopartículas/ultraestrutura , Ovalbumina , Tamanho da Partícula , Ratos Sprague-Dawley , Transdução de Sinais , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual/efeitos dos fármacos
6.
Artif Cells Nanomed Biotechnol ; 46(sup1): 751-762, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29421940

RESUMO

Visceral leishmaniasis (VL) is World Health Organization designated most serious leishmaniasis with an annual mortality rate of 50,000. Even after country specific eradication programs, the disease continues to multiply with added complexities like resistance development, drug hypersensitivity and associated infections. Newer therapeutic interventions are urgently warranted to control the spread. Present study aims to arrive at terpenoid andrographolide engineered gold nanoparticle (AGAunps) facile synthesis and its efficacy evaluations against wild and drug resistant VL strains for the first time. Molecular bio-organic conjugation of AGAunp was confirmed in FT-IR and EDAX studies. Nano-gold plasmon response was recorded at 543 nm and the average size in TEM was 14 nm. SAED pattern and XRD observations proved fcc crystalline structure of nano-gold. AGAunp recorded spherical geometry in AFM and TEM. PDI value of 0.137 revealed the monodisperse nature of the nano-scale population. AGAunp exhibited strong antileishmanicidal effect both against wild type (IC50 19 ± 1.7 µM) and sodium stibogluconate (IC50 55 ± 7.3 µM)/paromomycin (IC50 41 ± 6 µM) resistant strains. Complete macrophage uptake AGAunp's occured within two hours exposure. AGAunp macrophage cytotoxicity was significantly lower as compared to Amphotericin-B. Low toxic Andrographolide engineered gold nanoparticle emerged as promising alternatives in the control of wild and drug resistant VL.


Assuntos
Diterpenos/química , Resistência a Medicamentos/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Leishmaniose Visceral/tratamento farmacológico , Nanopartículas Metálicas/química , Animais , Transporte Biológico , Feminino , Ouro/metabolismo , Ouro/uso terapêutico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula
7.
Int J Nanomedicine ; 12: 4849-4868, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744120

RESUMO

BACKGROUND: Type I hypersensitivity is an allergic reaction characterized by the overactivity of the immune system provoked by normally harmless substances. Glucocorticoids, anti-histamines, or mast cell stabilizers are the choices of treatment for type I hypersensitivity. Even though these drugs have the anti-allergic effect, they can have several side effects in prolong use. Cedrol is the main bioactive compound of Cedrus atlantica with anti-tumor, anti-oxidative, and platelet-activating factor inhibiting properties. METHODS: In this study, the preparation and anti-anaphylactic effect of cedrol-loaded nanostructured lipid carriers (NLCs) were evaluated. NLCs were prepared using Compritol® 888 ATO and triolein as lipid phase and vitamin E d-α-tocopherylpolyethyleneglycol 1000 succinate, soya lecithin, and sodium deoxycholate as nanoparticle stabilizers. RESULTS: The average diameter of cedrol-NLCs (CR-NLCs) was 71.2 nm (NLC-C1) and 91.93 nm (NLC-C2). The particle had negative zeta potential values of -31.9 mV (NLC-C1) and -44.5 mV (NLC-C2). Type I anaphylactoid reaction in the animal model is significantly reduced by cedrol and cedrol-NLC. This in vivo activity of cedrol resulted that cedrol suppressed compound 48/80-induced peritoneal mast cell degranulation and histamine release from mast cells. Furthermore, compound 48/80-evoked Ca2+ uptake into mast cells was reduced in a dose-dependent manner by cedrol and cedrol-NLC. Studies confirmed that the inhibition of type I anaphylactoid response in vivo in mice and compound 48/80-induced mast cell activation in vitro are greatly enhanced by the loading of cedrol into the NLCs. The safety of cedrol and CR-NLC was evaluated as selectivity index (SI) with prednisolone and cromolyn sodium as positive control. SI of CR-NLC-C2 was found to be 11.5-fold greater than both prednisolone and cromolyn sodium. CONCLUSION: Administration of CR-NLC 24 hours before the onset of anaphylaxis can prevent an anaphylactoid reaction. NLCs could be a promising vehicle for the oral delivery of cedrol to protect anaphylactic reactions.


Assuntos
Anafilaxia/tratamento farmacológico , Portadores de Fármacos/química , Mastócitos/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Terpenos/administração & dosagem , Administração Oral , Animais , Degranulação Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Ácidos Graxos , Feminino , Liberação de Histamina/efeitos dos fármacos , Lipídeos/administração & dosagem , Lipídeos/química , Masculino , Mastócitos/fisiologia , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanoestruturas/química , Sesquiterpenos Policíclicos , Terpenos/farmacologia , Trioleína/química , Vitamina E/química , p-Metoxi-N-metilfenetilamina/efeitos adversos
8.
Int J Biol Macromol ; 102: 996-1008, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28465178

RESUMO

Visceral leishmaniasis (VL) is a life-threatening disease caused by Leishmania donovani due to uncontrolled parasitisation of liver, spleen, and bone marrow. Ursolic acid (UA), a promising anti-inflammatory, anti-bacterial and anti-diabetic drug used successfully for treatment of ailments. Development of new delivery system is extremely urgent for UA with better efficacy and fewer side effects. The aim of present research work was to formulate and evaluate the potential anti-leishmanial activity of UA loaded N-octyl-chitosan surface decorated nanostructured lipid carrier system (UA-NLC) for delivery to the macrophages for VL. UA-NLC were prepared and characterized for shape, size, fourier transforms scanning electron microscopy (FESEM), transmittance electron microscopy (TEM), entrapment efficiency and in vitro drug release. The results indicate that the formulated UA-NLC had nano size range (103.7±2.8nm to 143.0±3.8nm) with high drug loading capacity (12.05±0.54%) and entrapment efficiency (88.63±2.7%). Ex vivo drug uptake by macrophage was also evaluated. The UA-NLC was more effective against AG83 wild type (12 fold), SSG-R (4 fold), PMM-R (4 fold) and GE1 field isolated (3 fold) cellular amastigotes than its free form. In vivo study showed orally effective UA-NLC could suppress the parasite burden to 98.75%.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Leishmaniose/tratamento farmacológico , Lipídeos/química , Nanoestruturas/química , Triterpenos/química , Triterpenos/farmacologia , Administração Oral , Animais , Desenho de Fármacos , Liberação Controlada de Fármacos , Feminino , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/química , Triterpenos/administração & dosagem , Triterpenos/uso terapêutico
9.
Eur J Pharm Sci ; 104: 196-211, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28400285

RESUMO

Leishmaniasis is an epidemic in various countries, and the parasite Leishmania donovani is developing resistance against available drugs. In the present study the antileishmanial action of cedrol was evaluated in vitro and in vivo. Activity potentiation was achieved via nanostructured lipid carrier (NLC) complexation of cedrol. Cedrol-loaded NLC was prepared through the hot-melting emulsification-ultrasonication method. The cedrol- NLC prepared did not require the use of any organic solvents. The characterization of NLC-C1 and NLC-C2 revealed that particle size was 46.62nm and 54.73nm for 3.85%, and 7.48% drug loading, respectively and negative charge of -19.2mV and -23.7mV. The cedrol-loaded NLC were found to be spherical with a smooth surface. Drug-carrier interactions were clearly visualized in FT-IR studies. Incorporation of cedrol in NLC was ascertained in DSC and XRD analysis. Antileishmanial activities of free cedrol and cedrol-NLC were performed against L. donovani wild-type, sodium stibogluconate, paromomycin and field isolated resistant strains in axenic amastigotes and amastigotes in macrophage model. Coumarin-6 loaded NLC nanoparticles were assessed for macrophage internalization in confocal microscopic studies. Cedrol showed significant antileishmanial activity in wild-type (IC50=1.5µM), sodium stibogluconate resistant (IC50=2µM), paromomycin resistant (IC50=1.8µM) and field isolated resistant (IC50=1.35µM) strains in macrophage together with cytotoxicity (CC50=74µM) in mouse peritoneal macrophage cells. Incorporation of cedrol in NLC-C2 resulted in 2.1-fold and 2-fold increase in selectivity indexes (CC50/IC50) for wild-type and drug resistant strains, respectively. In addition, in vivo studies revealed that bioactivity of NLC-C2 were 2.3 to 3.8-fold increased in wild-type and 3 to 4.9-fold increased in drug resistant strains when compared with free cedrol; administered orally in mouse leishmaniasis model. Overall, NLC-C2 showed superior antileishmanial activity to free cedrol and miltefosine in oral dose. These findings support the use of NLCs for oral delivery of poorly water-soluble antileishmanial drugs in treatment of leishmaniasis. CHEMICAL COMPOUNDS: Cedrol (PubChem CID: 65575); Compritol® 888 ATO (PubChem CID: 62726); Triolein (PubChem CID: 5497163); Pluronic F68 (PubChem CID: 24751); Soya lecithin (PubChem CID: 57369748); Sodium deoxycholate (PubChem CID: 23668196); Miltefosine (PubChem CID: 3599); Paromomycin (PubChem CID: 165580); Amphotericin B (PubChem CID: 5280965); Sodium stibogluconate (PubChem CID: 16683012).


Assuntos
Antiprotozoários/administração & dosagem , Portadores de Fármacos/administração & dosagem , Leishmania donovani/efeitos dos fármacos , Terpenos/administração & dosagem , Animais , Antiprotozoários/química , Antiprotozoários/uso terapêutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Resistência a Medicamentos/efeitos dos fármacos , Feminino , Leishmania donovani/crescimento & desenvolvimento , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Lipídeos , Fígado/efeitos dos fármacos , Fígado/parasitologia , Masculino , Camundongos Endogâmicos BALB C , Nanoestruturas , Sesquiterpenos Policíclicos , Baço/efeitos dos fármacos , Baço/parasitologia , Terpenos/química , Terpenos/uso terapêutico
10.
Int J Biol Macromol ; 93(Pt A): 961-970, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27645930

RESUMO

Oleanolic acid (OA) has low aqueous solubility and low permeability, which results poor bioavailability. To surmount the inadequacy, our aim was to fabricate oleanolic acid loaded poly lactic co- glycolic acid (PLGA)- d-α- tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles, which could be efficacious for the treatment of Leishmania donovani mediated visceral leishmaniasis (VL). OA loaded PLGA- TPGS nanoparticles were prepared by emulsion solvent evaporation technique. Cellular uptake was investigated. In vitro cumulative drug release study was carried out. In vitro susceptibility was confirmed against the amastigotes of Leishmania donovani AG83 wild and drug resistant strains. In vivo antileishmanial activity was evaluated against wild type amastigotes of L. donovani. OA loaded nanoparticles were successfully formulated. The highest drug loading was found to be 11.08%±0.35%. 85.66%±0.56% was the highest in vitro OA release for 30days among the formulations. In vivo study revealed that, 98.82±1.92% amastigote burden in spleen of BALB/c mice were suppressed by the polymeric nanoformulation of OA. Experimental OA nanoparticle formulation proved itself as an attractive carrier for OA which was significantly efficacious against both in vitro and in vivo amastigote form of Leishmania donovani than pure OA for chemotherapeutic intervention of visceral leishmaniasis.


Assuntos
Portadores de Fármacos/administração & dosagem , Leishmaniose Visceral/tratamento farmacológico , Nanopartículas/administração & dosagem , Ácido Oleanólico/administração & dosagem , Tripanossomicidas/administração & dosagem , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Concentração Inibidora 50 , Ácido Láctico/química , Leishmania donovani/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vitamina E/química
11.
Acta Trop ; 158: 97-106, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26940000

RESUMO

Leishmaniasis is an epidemic in various countries, and the parasite Leishmania donovani is developing resistance against available drugs. In the present study the antileishmanial action of piperolactam A (PL), isolated after bioactivity guided fractionation from root extracts of Piper betle was accentuated in detail. Activity potentiation was achieved via cyclodextrin complexation. Crude hydro-ethanolic extract (PB) and three fractions obtained from PB and fabricated PL-hydroxypropyl-ß-cyclodextrin (HPBCD) nanoparticles were evaluated for antileishmanial activity. Tests were performed against L. donovani wild-type, sodium stibogluconate, paromomycin and field isolated (GE1) resistant strains in axenic amastigote and amastigote in macrophage models. PL-HPBCD complex was characterized and FITC loaded HPBCD nanoparticles were assessed for macrophage internalization in confocal microscopic studies. Isolated and purified PL from most potent, alkaloid rich ethyl acetate fraction of PB showed high level of antileishmanial activities in wild-type (IC50=36 µM), sodium stibogluconate resistant (IC50=103 µM), paromomycin resistant (IC50=91 µM) and field isolated resistant (IC50=72 µM) strains together with cytotoxicity (CC50=900 µM) in mouse peritoneal macrophage cells. Inclusion of PL in HPBCD nanoparticles resulted in 10-fold and 4-10-fold increase in selectivity indexes (CC50/IC50) for wild-type and drug resistant strains, respectively. Drug-carrier interactions were clearly visualized in FT-IR studies. Complete incorporation of PL in HPBCD cavity was ascertained in DSC and XRD analyses. 180nm size stable nanospheres showed macrophage internalization within 1h of incubation. Piperolactam A (PL), a representative of the inchoate skeleton of aristolactam chassis might be the source of safe and affordable antileishmanial agents for the cure of deadly Leishmania infections.


Assuntos
Antiprotozoários/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Leishmania donovani/efeitos dos fármacos , Leishmaniose/prevenção & controle , Extratos Vegetais/farmacologia , beta-Ciclodextrinas/farmacologia , 2-Hidroxipropil-beta-Ciclodextrina , Animais , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas , Piper betle/química , Raízes de Plantas/química
12.
Avicenna J Phytomed ; 5(1): 69-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25767759

RESUMO

OBJECTIVES: Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). MATERIALS AND METHODS: Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. RESULTS: Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. CONCLUSIONS: The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions.

13.
ScientificWorldJournal ; 2014: 564573, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25478596

RESUMO

Development of oral amphotericin B (AmB) loaded nanoparticles (NPs) demands a novel technique which reduces its toxicity and other associated problems. Packing of AmB in between two oppositely charged ions by polyelectrolyte complexation technique proved to be a successful strategy. We have developed a novel carrier system in form of polyelectrolyte complex of AmB by using chitosan (CS) and porphyran (POR) as two oppositely charged polymers with TPP as a crosslinking agent. Initially POR was isolated from Porphyra vietnamensis followed by the fact that its alkali induced safe reduction in molecular weight was achieved. Formulation was optimized using three-factor three-level (3(3)) central composite design. High concentration of POR in NPs was confirmed by sulfated polysaccharide (SP) assay. Degradation and dissolution studies suggested the stability of NPs over wide pH range. Hemolytic toxicity data suggested the safety of prepared formulation. In vivo and in vitro antifungal activity demonstrated the high antifungal potential of optimized formulation when compared with standard drug and marketed formulations. Throughout the study TPP addition did not cause any significant changes. Therefore, these experimental oral NPs may represent an interesting carrier system for the delivery of AmB.


Assuntos
Anfotericina B/química , Anfotericina B/farmacocinética , Portadores de Fármacos/química , Nanopartículas/química , Administração Oral , Anfotericina B/efeitos adversos , Anfotericina B/uso terapêutico , Antifúngicos/química , Antifúngicos/uso terapêutico , Quitosana/química , Quitosana/uso terapêutico , Portadores de Fármacos/uso terapêutico , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/uso terapêutico , Polímeros/química , Polímeros/uso terapêutico , Sefarose/análogos & derivados , Sefarose/química , Sefarose/uso terapêutico
14.
J Bioenerg Biomembr ; 46(5): 395-402, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25107348

RESUMO

Leishmaniasis is a growing health problem in many parts of the world partly due to drug resistance of the parasite. This study reports on the fisibility of studying mitochondrial properties of two forms of wild-type L. donovani through the use of selective inhibitors. Amastigote forms of L. donovani exhibited a wide range of sensitivities to these inhibitors. Mitochondrial complex II inhibitor thenoyltrifluoroacetone and FoF1-ATP synthase inhibitors oligomycin and dicyclohexylcarbodiimide were refractory to growth inhibition of amastigote forms, whereas they strongly inhibited the growth of promastigote forms. This result indicated that complex II and FoF1-ATP synthase were not functional in amastigote forms suggesting the presence of attenuated oxidative phosphorylation in the mitochondria of amastigote forms. In contrast, mitochondrial complex I inhibitor rotenone and complex III inhibitor antimycin A inhibited cellular multiplication and substrate level phosphorylation in amastigote forms, suggesting the role of complex I and complex III for the survival of amastigote forms. Further we studied the mitochondrial activities of both forms by measuring oxygen consumption and ATP production. In amastigote form, substantial ATP formation by substrate level phosphorylation was observed in NADPH-fumarate, NADH-fumarate, NADPH-pyruvate and NADH-pyruvate redox couples. None of the redox couple generated ATP formation was inhibited by FoF1-ATP synthase inhibitor oligomycin. Therefore, we may conclude that there are significant differences between these two forms of L. donovani in respect of mitochondrial bioenergetics. Our results demonstrated bioenergetic disfunction of amastigote mitochondria. Therefore, these alterations of metabolic functions might be a potential chemotherapeutic target.


Assuntos
Leishmania donovani/metabolismo , Mitocôndrias/metabolismo , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Leishmania donovani/classificação , Fosforilação Oxidativa , Proteínas de Protozoários/metabolismo
15.
Acta Parasitol ; 59(1): 11-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24570045

RESUMO

Leishmania, the causative agent of various forms of leishmaniasis, is the significant cause of morbidity and mortality. Regarding energy metabolism, which is an essential factor for the survival, parasites adapt to the environment under low oxygen tension in the host using metabolic systems which are very different from that of the host mammals. We carried out the study of susceptibilities to different inhibitors of mitochondrial electron transport chain and studies on substrate level phosphorylation in wild-type L. donovani. The amastigote forms of L. donovani are independent on oxidative phosphorylation for ATP production. Indeed, its cell growth was not inhibited by excess oligomycin and dicyclohexylcarbodiimide, which are the most specific inhibitors of the mitochondrial Fo/F1-ATP synthase. In contrast, mitochondrial complex I inhibitor rotenone and complex III inhibitor antimycin A inhibited amastigote cell growth, suggesting the role of complex I and complex III in cell survival. Complex II appeared to have no role in cell survival. To further investigate the site of ATP production, we studied the substrate level phosphorylation, which was involved in the synthesis of ATP. Succinate-pyruvate couple showed the highest substrate level phosphorylation in amastigotes whereas NADH-fumarate and NADH-pyruvate couples failed to produce ATP. In contrast, NADPH-fumarate showed the highest rate of ATP formation in promastigotes. Therefore, we can conclude that substrate level phosphorylation is essential for the survival of amastigote forms of Leishmania donovani.


Assuntos
Trifosfato de Adenosina/metabolismo , Leishmania donovani/metabolismo , Metabolismo Energético/fisiologia , Regulação da Expressão Gênica/fisiologia
16.
PLoS One ; 8(12): e81492, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24339938

RESUMO

Visceral leishmaniasis (VL) is a chronic protozoan infection in humans associated with significant global morbidity and mortality. There is an urgent need to develop drugs and strategy that will improve therapeutic response for effective clinical treatment of drug resistant VL. To address this need, andrographolide (AG) nanoparticles were designed with P-gp efflux inhibitor vitamin E TPGS (D-α-tocopheryl polyethyleneglycol 1000 succinate) for sensitivity against drug resistant Leishmania strains. AG loaded PLGA (50∶50) nanoparticles (AGnps) stabilized by vitamin E TPGS were prepared for delivery into macrophage cells infested with sensitive and drug resistant amastigotes of Leishmania parasites. Physico-chemical characterization of AGnps by photon correlation spectroscopy exhibited an average particle size of 179.6 nm, polydispersity index of 0.245 and zeta potential of -37.6 mV. Atomic force microscopy and transmission electron microscopy visualization revealed spherical nanoparticles with smooth surfaces. AGnps displayed sustained AG release up to 288 hours as well as minimal particle aggregation and drug loss even after three months study period. Antileishmanial activity as revealed from selectivity index in wild-type strain was found to be significant for AGnp with TPGS in about one-tenth of the dosage of the free AG and one-third of the dosage of the AGnp without TPGS. Similar observations were also found in case of in vitro generated drug resistant and field isolated resistant strains of Leishmania. Cytotoxicity of AGnp with and without TPGS was significantly less than standard antileishmanial chemotherapeutics like amphotericin B, paromomycin or sodium stibogluconate. Macrophage uptake of AGnps was almost complete within one hour as evident from fluorescent microscopy studies. Thus, based on these observations, it can be concluded that the low-selectivity of AG in in vitro generated drug resistant and field isolated resistant strains was improved in case of AG nanomedicines designed with vitamin E TPGS.


Assuntos
Diterpenos/química , Diterpenos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/crescimento & desenvolvimento , Nanopartículas/química , Vitamina E/análogos & derivados , Animais , Transporte Biológico/efeitos dos fármacos , Cápsulas , Diterpenos/metabolismo , Interações Medicamentosas , Estabilidade de Medicamentos , Feminino , Cinética , Ácido Láctico/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoglicóis/farmacologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vitamina E/farmacologia
17.
Int J Biol Macromol ; 57: 50-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23500431

RESUMO

Our investigation explores the immuno-efficiency of sulphated polysaccharides enriched Porphyra vietnamenis. Isolated polysaccharide fraction (17.1-25.8%) was characterized by FTIR and NMR spectroscopy which showed the presence of typical linear backbone structure called as porphyran. Oral administration of porphyran (200-500 mg/kg) evoked a significant (P ≤ 0.05) increase in weight of the thymus, spleen and lymphoid organ cellularity. The total leucocyte and lymphocyte count was increased significantly (P<0.005). The increase in the percent neutrophil adhesion to nylon fibres as well as a dose-dependent increase in antibody titre values was observed. A decreased response to DTH reaction induced by SRBC was recorded. A potential phagocytic response was seen and significant changes were observed in the formation of formazone crystals. It also prevented myelosuppression in cyclophosphamide drug treated rats. The results indicated that P. vietnamenis possesses potential immunomodulatory activity and has therapeutic potential for the prevention of autoimmune diseases.


Assuntos
Formação de Anticorpos/efeitos dos fármacos , Fatores Imunológicos , Neutrófilos/metabolismo , Porphyra/química , Sefarose/análogos & derivados , Administração Oral , Animais , Formação de Anticorpos/imunologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/imunologia , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Contagem de Linfócitos , Camundongos , Neutrófilos/imunologia , Ratos , Ratos Wistar , Sefarose/química , Sefarose/farmacologia
18.
Colloids Surf B Biointerfaces ; 107: 27-34, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23466539

RESUMO

Gold nanoparticles (Aunp) through biogenetic processes have induced enormous interest for lower toxicity and precise applications. A rapid, one pot synthesis for uniformly sized gold nanoparticles was developed using polyphenolic compound quercetin. Reduction process was followed at low temperatures in a simple bath type sonicator. Nanoparticle plasmon response was recorded at 540 nm and the average size in TEM was observed at 15.07 nm. Detailed X-ray diffraction (XRD) observations proved fcc crystalline structure of metallic gold and the Fourier transform infrared (FTIR) analysis has confirmed nanoparticles conjugation with quercetin. Leishmaniasis, is a neglected tropical disease (NTD) classified by the World Health Organization (WHO). The leishmanial parasite multiply in host macrophages and most strains have developed drug resistance to available chemotherapeutics. Drug delivery is therefore a major problem in macrophage specific leishmanial parasite infections. New quercetin conjugated gold nanoparticles (QAunp) were successfully evaluated for the first time against leishmanial macrophage infections. Antileishmanial efficiency of QAunp was established against wild type (IC50 15±3), sodium stibogluconate resistant strain (IC50 40±8) and the paramomycin resistant (IC50 30±6) strains. Macrophage uptake of QAunp was complete within an hour as observed in TEM experiments.


Assuntos
Resistência a Medicamentos , Ouro/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Nanotecnologia/métodos , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Resistência a Medicamentos/efeitos dos fármacos , Tratamento Farmacológico , Ouro/farmacologia , Humanos , Leishmania donovani , Leishmaniose Visceral/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Macrófagos/ultraestrutura , Nanopartículas Metálicas/ultraestrutura , Quercetina/farmacologia , Quercetina/uso terapêutico , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
19.
J Microencapsul ; 29(7): 666-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22545676

RESUMO

Human immunodeficiency viruses (HIV) hide themselves in macrophages at the early stage of infection. Delivering drug in a sustained manner from polymeric nanoparticles in those cells could control the disease effectively. The study was intended to develop poly(d,l-lactic-co-glycolic acid)-based nanoparticles containing didanosine and to observe their uptake by macrophages in vitro. Various physicochemical evaluations related to nanoparticles, such as drug-excipient interaction, surface morphology, particle size, zeta potential, polydispersity index, drug loading, in vitro drug release and nanoparticle-uptake by macrophages in vitro were determined. Homogenising speeds and drug-polymer ratio varied drug loading and polydispersity index of nanoparticles, providing sustained drug release. Dimethyl sulphoxide/polyethylene glycol improved drug loading predominantly. Nanoparticle-uptake by macrophages was concentration dependent. Experimental nanoparticles successfully transported didanosine to macrophages in vitro, suggesting reduction of dose, thus minimising toxicity and side effects. Developed nanoparticle may control HIV infection effectively at an early stage.


Assuntos
Fármacos Anti-HIV , Didanosina , Infecções por HIV/tratamento farmacológico , HIV , Macrófagos Peritoneais/metabolismo , Nanopartículas/química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/farmacologia , Células Cultivadas , Preparações de Ação Retardada , Didanosina/química , Didanosina/farmacocinética , Didanosina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Ácido Láctico/química , Ácido Láctico/farmacocinética , Ácido Láctico/farmacologia , Macrófagos Peritoneais/citologia , Camundongos , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
20.
J Bioenerg Biomembr ; 43(2): 203-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21523408

RESUMO

The quinone composition of the transplasma membrane electron transport chain of parasitic protozoa Entamoeba histolytica was investigated. Purification of quinone from the plasma membrane of E. histolytica and its subsequent structural elucidation revealed the structure of the quinone as a methylmenaquinone-7 (thermoplasmaquinone-7), a napthoquinone. Membrane bound thermoplasmaquinone-7 can be destroyed by UV irradiation with a concomitant loss of plasma membrane electron transport activity. The abilities of different quinones to restore transplasma membrane electron transport activity in UV irradiated trophozoites were compared. The lost activity was recovered completely by the addition of thermoplasmaquinone-7, but ubiquinones are unable to restore the same. These findings clearly indicate that thermoplasmaquinone-7 acts as a lipid shuttle in the plasma membrane of the parasite to mediate electron transfer between cytosolic reductant and non permeable electron acceptors. This thermoplasmaquinone-7 differs from that of the mammalian host and can provide a novel target for future rational chemotherapeutic drug designing.


Assuntos
Membrana Celular/metabolismo , Entamoeba histolytica/metabolismo , Naftoquinonas/farmacologia , Desenho de Fármacos , Transporte de Elétrons/efeitos dos fármacos , Transporte de Elétrons/efeitos da radiação , Entamebíase/tratamento farmacológico , Entamebíase/metabolismo , Raios Ultravioleta
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