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1.
Nature ; 557(7706): 534-538, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29795256

RESUMO

Information and communication technologies have opened the way to new solutions for urban mobility that provide better ways to match individuals with on-demand vehicles. However, a fundamental unsolved problem is how best to size and operate a fleet of vehicles, given a certain demand for personal mobility. Previous studies1-5 either do not provide a scalable solution or require changes in human attitudes towards mobility. Here we provide a network-based solution to the following 'minimum fleet problem', given a collection of trips (specified by origin, destination and start time), of how to determine the minimum number of vehicles needed to serve all the trips without incurring any delay to the passengers. By introducing the notion of a 'vehicle-sharing network', we present an optimal computationally efficient solution to the problem, as well as a nearly optimal solution amenable to real-time implementation. We test both solutions on a dataset of 150 million taxi trips taken in the city of New York over one year 6 . The real-time implementation of the method with near-optimal service levels allows a 30 per cent reduction in fleet size compared to current taxi operation. Although constraints on driver availability and the existence of abnormal trip demands may lead to a relatively larger optimal value for the fleet size than that predicted here, the fleet size remains robust for a wide range of variations in historical trip demand. These predicted reductions in fleet size follow directly from a reorganization of taxi dispatching that could be implemented with a simple urban app; they do not assume ride sharing7-9, nor require changes to regulations, business models, or human attitudes towards mobility to become effective. Our results could become even more relevant in the years ahead as fleets of networked, self-driving cars become commonplace10-14.


Assuntos
Condução de Veículo/estatística & dados numéricos , Eficiência Organizacional , Veículos Automotores/estatística & dados numéricos , Meio Social , População Urbana , Simulação por Computador , Cidade de Nova Iorque
2.
Parasitol Res ; 121(5): 1379-1388, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35320838

RESUMO

Host-parasite interaction has always been an area of interest to the parasite biologists. The complex immune interactions between the parasite and/or the parasite-derived products with the host immune cells determine the fate of the disease biology. Parasitic organisms are widely equipped with a vast array of protective machineries including antioxidant enzymes to withstand the hostile condition inside the host body. The reactive oxygen species (ROS) generated inside the host as a result of parasitic intervention can be endured by the parasite by their own tools to ensure their survival. One such antioxidant enzyme in the filarial parasite that plays a significant role in redox homeostasis, survivability and disease progression is the thioredoxin reductase (TrxR). Herein, we have projected a crude lysate of the bovine filarial parasite Setaria cervi enriched with high TrxR enzyme activity has the capacity to downregulate lipopolysaccharide (LPS)-induced inflammatory macrophages. TrxR-mediated inhibition of the TLR4-NF-κB axis resulting into downregulation of the pro-inflammatory cytokines with concomitant upregulation of the anti-inflammatory cytokines supports the filarial parasite to produce an anti-inflammatory milieu which ultimately promotes worm survivability inside the host and pathogenesis.


Assuntos
Filarioidea , Parasitos , Setaria (Nematoide) , Animais , Anti-Inflamatórios , Antioxidantes/metabolismo , Bovinos , Citocinas/metabolismo , Inflamação , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Parasitos/metabolismo , Tiorredoxina Dissulfeto Redutase
3.
J Infect Dis ; 224(12 Suppl 2): S910-S914, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34668553

RESUMO

Informal slums are growing exponentially in the developing world and these will serve as the breeding ground for a future global pandemic. Virtually every sustainable development goal is unmet in slums around the globe thus we must act now to divert a global humanitarian crisis.


Assuntos
Doenças Transmissíveis , Pandemias , Áreas de Pobreza , Previsões , Humanos , População Urbana
4.
Scand J Immunol ; 93(4): e13001, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33247468

RESUMO

Lymphatic filariasis (LF) is the second leading cause of parasitic disabilities that affects millions of people in India and several other tropical countries. The complexity of this disease is endorsed by various immunopathological consequences such as lymphangitis, lymphadenitis and elephantiasis. The immune evasion strategies that a filarial parasite usually follows are chiefly initiated with the communication between the invaded parasites and parasite-derived molecules, with the Toll-like receptors (TLRs) present on the surface of the antigen-presenting cells (APCs). Classically, the filarial parasites interact with the DCs resulting in lowering of CD4+ T-cell responses. These CD4+ T-cell responses are the key players behind the immune-mediated pathologies associated with LF. In chronic stage, the canonical pro-inflammatory immune responses are shifted towards an anti-inflammatory subtype, which is favouring the parasite survivability within the host. The central theme of this review article is to present the overall immune response elicited when an APC, particularly a DC, encounters a filarial parasite.


Assuntos
Células Dendríticas/imunologia , Filariose Linfática/imunologia , Imunidade/imunologia , Parasitos/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antígenos de Helmintos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/parasitologia , Células Dendríticas/parasitologia , Filariose Linfática/parasitologia , Humanos , Inflamação/imunologia , Inflamação/parasitologia , Receptores Toll-Like/imunologia
5.
Appl Opt ; 59(28): 9032-9041, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104593

RESUMO

Infrared (IR) images are basically low-contrast in nature; hence, it is essential to enhance the contrast of IR images to facilitate real-life applications. This work proposes a novel adaptive clip-limit-oriented bi-histogram equalization (bi-HE) method for enhancing IR images. HE methods are simple in implementation but often cause over-enhancement due to the presence of long spikes. To reduce long spikes, this work suggests to apply a log-power operation on the histogram, where the log operation reduces the long spikes, and power transformation regains the shape of the histogram. First, a histogram separation point is generated applying the mean of the multi-peaks of the input histogram. After that, an alteration in the input histogram is done using the log-power process. Subsequently, a clipping operation on the altered histogram followed by redistribution of the clipped portion is performed to restrict over-enhancement. Next, the modified histogram is sub-divided using the histogram separation point. Finally, the modified sub-histograms are equalized independently. Simulation results show that the suggested method effectively improves the contrast of IR images. Visual quality evaluations and quantitative assessment demonstrate that the suggested method outperforms the state-of-the-art algorithms.

6.
Scand J Immunol ; 90(1): e12771, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31054156

RESUMO

Immunopolymorphism is considered as an important aspect behind the resistance or susceptibility of the host to an infectious disease. Over the years, researchers have explored many genetic factors for their role in immune surveillance against infectious diseases. Polymorphic characters in the gene encoding Toll-like receptors (TLRs) play profound roles in inducing differential immune responses by the host against parasitic infections. Protein(s) encoded by TLR gene(s) are immensely important due to their ability of recognizing different types of pathogen associated molecular patterns (PAMPs). This study reviews the polymorphic residues present in the nucleotide or in the amino acid sequence of TLRs and their influence on alteration of inflammatory signalling pathways promoting either susceptibility or resistance to major infectious diseases, including tuberculosis, leishmaniasis, malaria and filariasis. Population-based studies exploring TLR polymorphisms in humans are primarily emphasized to discuss the association of the polymorphic residues with the occurrence and epidemiology of the mentioned infectious diseases. Principal polymorphic residues in TLRs influencing immunity to infection are mostly single nucleotide polymorphisms (SNPs). I602S (TLR1), R677W (TLR2), P554S (TLR3), D299G (TLR4), F616L (TLR5), S249P (TLR6), Q11L (TLR7), M1V (TLR8), G1174A (TLR9) and G1031T (TLR10) are presented as the major influential SNPs in shaping immunity to pathogenic infections. The contribution of these SNPs in the structure-function relationship of TLRs is yet not clear. Therefore, molecular studies on such polymorphisms can improve our understanding on the genetic basis of the immune response and pave the way for therapeutic intervention in a more feasible way.


Assuntos
Doenças Transmissíveis/genética , Receptores Toll-Like/genética , Animais , Predisposição Genética para Doença , Humanos , Imunidade/genética , Vigilância Imunológica , Moléculas com Motivos Associados a Patógenos/imunologia , Polimorfismo Genético , Relação Estrutura-Atividade
7.
Langmuir ; 35(16): 5525-5533, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30889953

RESUMO

Recently, there has been a growth of research on the nonconjugated polymer exhibiting fluorescence property and it would be exciting if fluorescence property is developed in zwitterionic polymers because of their good water solubility. Poly(vinylidene fluoride) (PVDF) grafted with poly(dimethyl amino ethyl methacrylate) (PDMAEMA) is fractionated and a highly water-soluble fraction (PVDM-1) is quaternized with 1,3-propane sultone, producing a zwitterionic polymer, PVDF- g-PDMAEMA-sultone (PVDMS). PVDM-1 shows the fluorescence property with very low quantum yield (1%) in water, but on quaternization, fluorescence quantum yield increases to 8%. Transmission electron microscopy results indicate that the PVDM-1 cast from water has vesicular morphology, whereas PVDMS exhibits aggregated vesicular morphology. The 1H NMR spectra indicate the presence of 72 mol % DMAEMA in PVDM-1 wherein 66% of -NMe2 groups is quaternized upon postpolymerization modification. PVDM-1 exhibits absorption peaks at 210, 276, and 457 nm with a hump at 430 nm, whereas PVDMS exhibits two absorption peaks at 203 and 297 nm. PVDM-1 exhibits a broad emission peak at 534 nm, whereas PVDMS exhibits a sharp emission peak at 438 nm. An attempt has been made from density functional theory calculations to shed light on the origin of fluorescence in both PVDM-1 and in the zwitterionic PVDMS. The excitonic decay occurs from the lowest unoccupied molecular orbital (LUMO) of carbonyl group to the highest occupied molecular orbital (HOMO) of tertiary amine group for PVDM-1, whereas in PVDMS, the excitonic transition occurs from the LUMO situated over the quaternary ammonium group to the HOMO located on the electron-rich terminal sulfonate group.

8.
Parasitology ; 146(11): 1451-1461, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31104638

RESUMO

The present work aims to explore the mechanism of action of C-cinnamoyl glycoside as an antifilarial agent against the bovine filarial nematode Setaria cervi. Both apoptosis and autophagy programmed cell death pathways play a significant role in parasitic death. The generation of reactive oxygen species, alteration of the level of antioxidant components and disruption of mitochondrial membrane potential may be the causative factors that drive the parasitic death. Monitoring of autophagic flux via the formation of autophagosome and autophagolysosome was detected via CYTO ID dye. The expression profiling of both apoptotic and autophagic marker proteins strongly support the initial findings of these two cell death processes. The increased interaction of pro-autophagic protein Beclin1 with BCL-2 may promote apoptotic pathway by suppressing anti-apoptotic protein BCL-2 from its function. This in turn partially restrains the autophagic pathway by engaging Beclin1 in the complex. But overall positive increment in autophagic flux was observed. Dynamic interaction and regulative balance of these two critical cellular pathways play a decisive role in controlling disease pathogenesis. Therefore, the present experimental work may prosper the chance for C-cinnamoyl glycosides to become a potential antifilarial therapeutic in the upcoming day after detail in vivo study and proper clinical trial.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Filaricidas/farmacologia , Glicosídeos/farmacologia , Setaria (Nematoide)/efeitos dos fármacos , Wuchereria bancrofti/efeitos dos fármacos , Animais , Setaria (Nematoide)/fisiologia , Wuchereria bancrofti/fisiologia
9.
Phys Chem Chem Phys ; 21(20): 10726-10737, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31086920

RESUMO

The emerging category of magneto-fluorescent tartrate-modified MnFe2O4 nano hollow spheres (T-MnFe2O4 NHSs) can be considered as promising candidates for biomedical applications. The interaction of bovine serum albumin (BSA) with T-MnFe2O4 NHSs has been studied using several spectroscopic techniques, which suggest that the interaction occurs by an electrostatic mechanism. Furthermore, BSA enhances the charge transfer transition from the tartrate ligand to the metal ions along with the d-d transition of Fe3+ ions on NHSs surfaces at different pH. Very strong salt bridge formation occurs between the lysine of the BSA surface and the tartrate in basic medium (pH 10), followed by the acidic (pH 3) and neutral medium (pH 7), respectively. Systematic fluorescence microscopic analysis reveals that BSA significantly enhances the contrast of T-MnFe2O4 NHSs in UV and blue light excitation because of the extended charge transfer from BSA to T-MnFe2O4 NHSs. Our report demonstrates great potential in the field of nanotechnology and biomedical applications. In vitro toxicity analysis using RAW 264.7 celline and in vivo studies on Wister rats revealed that the T-MnFe2O4 NHSs are benign. Furthermore, T-MnFe2O4 NHSs also appear to be an antimicrobial agent. Therefore, T-MnFe2O4 NHSs can be explored for future therapeutic applications.


Assuntos
Compostos Férricos/química , Compostos de Manganês/química , Nanosferas/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Tartaratos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Compostos Férricos/toxicidade , Fluorescência , Camundongos , Nanosferas/toxicidade , Células RAW 264.7 , Ratos
10.
Nat Mater ; 16(12): 1216-1224, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29058729

RESUMO

Non-volatile memories will play a decisive role in the next generation of digital technology. Flash memories are currently the key player in the field, yet they fail to meet the commercial demands of scalability and endurance. Resistive memory devices, and in particular memories based on low-cost, solution-processable and chemically tunable organic materials, are promising alternatives explored by the industry. However, to date, they have been lacking the performance and mechanistic understanding required for commercial translation. Here we report a resistive memory device based on a spin-coated active layer of a transition-metal complex, which shows high reproducibility (∼350 devices), fast switching (≤30 ns), excellent endurance (∼1012 cycles), stability (>106 s) and scalability (down to ∼60 nm2). In situ Raman and ultraviolet-visible spectroscopy alongside spectroelectrochemistry and quantum chemical calculations demonstrate that the redox state of the ligands determines the switching states of the device whereas the counterions control the hysteresis. This insight may accelerate the technological deployment of organic resistive memories.

12.
J Infect Dis ; 215(6): 954-965, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28453850

RESUMO

Background: Lymphatic filariasis, frequently caused from Wuchereria bancrofti infection, is endemic in several parts of the globe and responsible for human health problems and socioeconomic loss to a large extent. Inflammatory consequences originating from host-parasite interaction play a major role in the disease pathology and allied complications. The identity of the key mediator of this process is yet unknown in filarial research. Methods: Microfilarial protein (MfP) was isolated from the sheath of W. bancrofti microfilariae through ultrafiltration, followed by chromatographic separation. Expression of signaling molecules was studied by enzyme-linked immunosorbent assay and immunoblotting. Binding of MfP to Toll-like receptor 4 (TLR4) was determined by co-immunoprecipitation, fluorescein isothiocyanate-probing, and surface plasmon resonance analysis. Results: We found that MfP (approximately 70 kDa) binds to macrophage-TLR4 and triggers nuclear factor kappa beta activation that upregulates secretion of proinflammatory cytokines. Microfilarial protein failed to induce inflammation in either TLRKO macrophage or macrophage treated with TLR4 inhibitor, indicating that MfP acts through TLR4. We have also detected phenotypic transformation of macrophages from anti-inflammatory (M2) to proinflammatory (M1) subtype after incubation with MfP. Conclusions: Microfilarial protein appears to be a new ligand of TLR4 from W. bancrofti. Determination of its functional attributions in the host-parasite relationship, especially immunopathogenesis of filarial infection, may improve our understanding.


Assuntos
Antígenos de Helmintos/imunologia , Proteínas de Helminto/imunologia , Macrófagos/imunologia , Receptor 4 Toll-Like/imunologia , Wuchereria bancrofti/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Células HEK293 , Interações Hospedeiro-Parasita , Humanos , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Microfilárias/imunologia
13.
Exp Parasitol ; 160: 39-48, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26627139

RESUMO

Green synthesis of silver nanomaterial plays a pivotal role in the growing field of nanotechnology. Development of anti-parasitic drugs from plant metabolites has been in regular practice from the ancient period but most of them were discarded due to their inefficiency to control diseases effectively. At present, nanoparticles are used for developing anti-parasitic therapy for their unique properties such as smallest in size, bio-ability, bio-compatibility and penetration capacity into a cell. The present study aims at synthesis of silver nanoparticles (AgNPs) by using funicles extract of Acacia auriculiformis and tests its efficacy as antifilarial. Experimental evidence show that AgNPs are effective at a very low concentration compared to crude plant extracts. Synthesis of these nanoparticles is a single-step, biogenic, cost effective and eco-friendly process. Synthesized nanoparticles were characterized by UV-Vis spectroscopy, TEM, SAED, FTIR, EDX, FESEM and Z-potential. The antifilarial efficacy of AgNPs was tested against different life cycle stages of bovine filarial parasite Setaria cervi by morphological study, motility assessment and viability assay. These nanoparticles are found to have antifilarial activity with LC50 of 5.61 µg/mL and LC90 of 15.54 µg/mL against microfilaria of S. cervi. The microscopic findings and the detailed molecular studies confirmed that green synthesized AgNPs were effective enough to induce apoptosis through up regulation of ROS (reactive oxygen species).


Assuntos
Acacia/química , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Setaria (Nematoide)/efeitos dos fármacos , Animais , Apoptose/fisiologia , Bovinos , Fragmentação do DNA , DNA de Helmintos/química , DNA de Helmintos/genética , Feminino , Marcação In Situ das Extremidades Cortadas , Macrófagos Peritoneais/efeitos dos fármacos , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Extratos Vegetais/química , Ratos , Ratos Wistar , Setaria (Nematoide)/citologia , Setaria (Nematoide)/genética , Setaria (Nematoide)/metabolismo , Setaríase/parasitologia , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Regulação para Cima
14.
Prep Biochem Biotechnol ; 46(5): 440-5, 2016 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26176798

RESUMO

The present study reports statistical optimization of growth conditions of an opportunistic fungal strain Pichia guilliermondii, isolated from the blood of patients suffering from bancroftian filariasis. Seven key determinants, namely, primary inoculums size (%), volume (mL) and pH of media, serum proportion, temperature (°C), incubation time (hr), and agitation speed (rpm) that influence in vitro growth of the pathogen were optimized statistically using response surface methodology (RSM). RSM with seven factors and two-level Box-Behnken design was employed for designing experimental run, prediction of case statistics, suitable exploration of quadratic response surfaces, and constructing a second-order polynomial equation. Analysis of variance (ANOVA) showed that primary inoculums size, volume of culture media, temperature, incubation time, and agitation speed exert most significant influence over fungal growth. The RSM study predicted that optimum fungal growth can be obtained using 10% primary inoculums size in 100 mL culture media with pH 6.0, 6.28% serum, 32.5°C temperature, and 24 hr of incubation, alongside agitation speed at 400 rpm. The desirability of the optimized growth model for P. guilliermondii is 99.123%, which indicated its accuracy and acceptability. Finally, the optimized growth module illustrated in the study could be useful in improving in vitro growth of clinically important P. guilliermondii.


Assuntos
Pichia/crescimento & desenvolvimento , Meios de Cultura , Temperatura
15.
Indian J Exp Biol ; 53(9): 574-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26548077

RESUMO

Organophosphorus (OP) compounds commonly used as pesticides in agriculture cause serious health problems to living beings. The present study enumerates the ameliorating effect of ginger extract (GE) against phosphamidon (PHO, an organophosphorus insecticide) induced hepatotoxicity. GE was prepared from dried ginger and characterized for compound profile and antioxidant activity. Eight groups of albino rats (n = 6) were treated with 1/5th lethal dose of PHO for 5-20 days. Out of the treated 8 groups, 4 were simultaneously fed with GE (1 mg/kg body wt.) along with PHO. Alterations in the levels of hepatocellular oxidative stress (OS) markers in the treated groups indicated an enhanced generation of reactive oxygen species (ROS) and oxidative stress (OS). Upregulation of apoptotic markers, DNA fragmentation and appearance of apoptotic nuclei suggested induction of apoptosis in the liver cell that was found to be attenuated after GE treatment. Moreover, no toxicity and mortality was observed up to 100 mg/kg dose of GE for 30 days in the rat model studied. Thus, GE can be considered as an effective, economical and safe extract to circumvent PHO-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Inseticidas/toxicidade , Intoxicação por Organofosfatos/tratamento farmacológico , Fosfamidona/toxicidade , Fitoterapia , Extratos Vegetais/uso terapêutico , Zingiber officinale , Animais , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Etanol , Hepatócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Função Hepática , Masculino , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/análise , Solventes , Ultrafiltração
16.
Pharm Biol ; 53(6): 813-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25720973

RESUMO

CONTEXT: Lymphatic filariasis is a major neglected tropical disease. Diospyros perigrena Gurke (Ebenaceae) was selected for antifilarial chemotherapy because of unavailability of proper medicine. In India, different parts of this plant were used for the treatment of diabetes, diarrhea, dysentery, cholera, mouth ulcers, and wounds. OBJECTIVE: The present study was undertaken to access antifilarial potential and mechanism of action of n-butanol extract (NBE) of D. perigrena stem bark on Setaria cervi Rudolphi (Onchocercidae). MATERIALS AND METHODS: In vitro efficacy and apoptotic mechanism were evaluated by Hoechst, TUNEL, DNA fragmentation assay, pro- and anti-apoptotic gene expression in NBE (250, 125, 62.5, 31.25, and 15.6 µg/ml)-treated S. cervi after 24 h of incubation. Reactive oxygen species (ROS) up-regulation was also determined by GSH, GST, SOD assays, and super oxide anion level. RESULTS: Significant in vitro antifilarial activity of NBE was found 50% inhibitory concentration (IC50): adult = 57.6 µg/ml, microfilariae (mf) = 56.1 µg/ml, and lethal dose (LD100) in mf is 187.17 µg/ml) after 24 h of treatment. NBF-induced apoptosis was proved by Hoechst, TUNEL, RT-PCR, and Western blot method. NBF (250 µg/ml) decreased the level of GSH (17.8%) and GST (65.4%), increased SOD activity (1.42-fold) and super oxide anion production (1.32-fold) in the treated parasite which culminated into ROS up-regulation. DISCUSSION AND CONCLUSION: NBE induced apoptosis in different life cycle stages of S. cervi. In future, a detailed study of NBF will give us a novel antifilarial compound which will be used for antifilarial chemotherapy.


Assuntos
Apoptose/efeitos dos fármacos , Diospyros/química , Filaricidas/farmacologia , Casca de Planta/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Setaria (Nematoide)/efeitos dos fármacos , 1-Butanol , Animais , Bisbenzimidazol , Corantes , DNA/efeitos dos fármacos , Filariose/tratamento farmacológico , Filariose/psicologia , Marcação In Situ das Extremidades Cortadas , Setaria (Nematoide)/metabolismo , Solventes , Sais de Tetrazólio , Tiazóis
17.
Exp Parasitol ; 136: 41-58, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24275557

RESUMO

Lymphatic filariasis, a global cause of morbidity needs much more attention in developing potent therapeutics that can be effective against both microfilariae (mf) and adults. Efficient botanicals that can induce apoptosis of filarial parasites possibly can provide a direction towards developing new class of antifilarials. In this work we have evaluated the antifilarial efficacy of an optimized polyphenol rich ethanolic extract of Azadirachta indica leaves (EEA). A. indica A. Juss has been widely used in the traditional Indian medicinal system 'Ayurveda' for the treatment of a variety of ailments. A thorough investigation towards biochemical and molecular mechanisms describing ROS mediated apoptosis in Setaria cervi was performed. Motility reduction, MTT reduction assay and dye exclusion test have confirmed the micro- and macrofilaricidal potential of EEA. Alterations were visible in mf and trichrome stained section of EEA-treated adult worms. We have found cellular disturbances in EEA-treated parasites characterized by chromatin condensation, in situ DNA fragmentation and nucleosomal DNA laddering. Depletion in worm GSH level and elevation in parasite GST, SOD, catalase, GPx and superoxide anion indicated the generation of ROS. Our results provided experimental evidence supporting that EEA causes a decreased expression of anti-apoptotic genes and increased pro-apoptotic gene expression at the level of both transcription and translation. Here we are reporting for the first time that antifilarial activity of EEA is mediated by ROS up regulation and apoptosis.


Assuntos
Azadirachta/química , Filaricidas/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Setaria (Nematoide)/efeitos dos fármacos , Análise de Variância , Animais , Apoptose/genética , Bovinos , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Filaricidas/isolamento & purificação , Regulação da Expressão Gênica/efeitos dos fármacos , Ivermectina/farmacologia , Masculino , Oxirredução/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Polifenóis/isolamento & purificação , Setaria (Nematoide)/genética , Setaria (Nematoide)/metabolismo
18.
Lymphology ; 46(1): 20-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23930438

RESUMO

Despite the development of minimal access dissection techniques, use of superficial groin dissection alone, and other recommendations to reduce morbidity in melanoma treatment, the incidence of lymphedema is still significant. The purpose of the current study was to assess the efficacy of microsurgical methods to limit the morbidity of inguinal lymphadenectomy. We conducted a retrospective review of patients who underwent groin dissection for melanoma treatment from February 2006 to April 2009. A total of 59 melanoma patients with positive groin lymph nodes comprised 18 patients (T-group) with melanoma in the trunk and 41 patients (E-group) who had melanoma in an extremity and currently have lymphedema. The T-group patients underwent primary prevention of lymphedema with microsurgical lymphatic-venous anastomoses (LVA) performed simultaneously with groin dissection. The E-group patients underwent LVA to treat the secondary lymphedema after an accurate oncological and lymphological assessment. Limb volume measurements and lymphoscintigraphy were performed pre- and postoperatively to assess short and long term outcome. No lymphedema occurred after microsurgical primary preventive approach in the T- group. Significant (average 80% reduction of pre-op excess volume) reduction of lymphedema resulted after microsurgical treatment for secondary leg lymphedema. Post-operative lymphoscintigraphy in 35 patients demonstrated patency of microsurgical anastomoses in all cases with an average follow-up of 42 months. Study results demonstrate that microsurgical LVA primary prevention prevented lymphedema after inguinal lymphadenectomy in the T-group patients. In addition, lymphatic-venous multiple anastomoses proved to be a successful treatment for clinical lymphedema with particular success if treated at the early stages.


Assuntos
Excisão de Linfonodo , Linfedema/prevenção & controle , Melanoma/secundário , Neoplasias Cutâneas/patologia , Adulto , Idoso , Anastomose Cirúrgica , Feminino , Seguimentos , Virilha , Humanos , Metástase Linfática , Vasos Linfáticos/cirurgia , Linfocintigrafia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos , Adulto Jovem
19.
Adv Mater ; 35(37): e2204551, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36043246

RESUMO

Electronic transitions in molecular-circuit elements hinge on complex interactions between molecules and ions, offering a multidimensional parameter space to embed, access, and optimize material functionalities for target-specific applications. This opportunity is not cultivated in molecular memristors because their low-temperature charge transport, which is a route to decipher molecular many-body interactions, is unexplored. To address this, robust, temperature-resilient molecular memristors based on a Ru complex of an azo aromatic ligand are designed, and current-voltage sweep measurements from room temperature down to 2 K with different cooling protocols are performed. By freezing out or activating different components of supramolecular dynamics, the local Coulombic interactions between the molecules and counterions that affect the electronic transport can be controlled. Operating conditions are designed where functionalities spanning bipolar, unipolar, nonvolatile, and volatile memristors with sharp as well as gradual analog transitions are captured within a single device. A mathematical design space evolves, thereof comprising 36 tuneable parameters in which all possible steady-state functional variations in a memristor characteristic can be attainable. This enables a deterministic design route to engineer neuromorphic devices with unprecedented control over the transformation characteristics governing their functional flexibility and tunability.

20.
Sci Rep ; 13(1): 7022, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120449

RESUMO

Volcanic rocks were among the most sought-after materials to produce grinding tools in antiquity because lavas lithologies, either mafic or felsic, ensured good wear resistance and grinding capacity with respect to many other kinds of rocks. The interest in findings made of vesciculated lavas, referable to parts of querns, mortars, and/or pestles of the Final Bronze Age site of Monte Croce Guardia (Arcevia) lies in the fact that this settlement was built upon limestones belonging to the sedimentary sequence of the Marche-Umbria Apennines (central Italy) and far away from potential raw materials of volcanic rocks. A petrologic study of 23 grinding tool fragments clearly indicates a provenance from the volcanic provinces of central Italy: Latium and Tuscany Regions. Few leucite tephrites (5) and one leucite phonolite lavas have a clear magmatic affinity with the high-K series of the Roman Volcanic Province (Latium) whereas the most abundant volcanic lithotype (17 samples) is represented by shoshonites (K-series) whose thin section texture, modal mineralogy and major-trace elements contents closely match with the shoshonite lavas from the Radicofani volcanic centre in the Tuscan Magmatic Province. At Radicofani (a volcanic neck in the eastern sector of Tuscany) a Final Bronze Age site coeval to that of Arcevia is present and a potential pathway corridor from that site towards Arcevia (air-line distance of ca. 115 km) is dotted with many settlements of the same age. Through analytical algorithms based on the slope and the different human-dependent cost-functions which can be applied to determine non-isotropic accumulated cost surface, least-cost paths and least-cost corridors, the best route from Radicofani to Monte Croce Guardia, approximately 140 km long, was simulated, with a walking time of 25-30 h, possibly using pack animals and wheel chariots. Three thousand years ago the Apennine Mountains did not thus constitute a barrier for human movements. This study also shed light on some other possible patterns of interactions between Final Bronze Age communities of central Italy through the present-day regions of Tuscany, Umbria and Marche, aimed towards the best performance of strategic economic activities at that time such as that of the transformation of cereals, and accompanied to cultural and social reasons.


Assuntos
Silicatos de Alumínio , Oligoelementos , Humanos , Itália
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