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1.
J Public Health Manag Pract ; 30: S162-S166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39041752

RESUMO

In New York City (NYC), hypertension and high cholesterol disproportionately affect residents with low household income and people of color. The NYC Health Department employed practice facilitation (PF) to help nonphysician staff assume added roles aligned with team-based care. The objective was to improve blood pressure (BP) and cholesterol management in 132 small primary care practices serving mostly patients of color. We categorized practices into higher or lower levels of integrated PF, defined as physicians and nonphysician staff collectively participating in PF. Higher integrated PF was associated with improvements in BP (rate ratio [RR] = 1.09, P-value < .05) and cholesterol management (RR = 1.12, P-value < .01). Nonphysician staff in higher integrated PF practices reported skills enhancement and improved teamwork. Involving nonphysician staff in PF-mediated quality improvement efforts can be an effective strategy to improve health outcomes in small clinical practices serving communities with a higher burden of chronic disease and disproportionately impacted by poverty and structural racism.


Assuntos
Melhoria de Qualidade , Humanos , Cidade de Nova Iorque , Atenção Primária à Saúde/normas , Hipertensão/terapia , Masculino
2.
J Am Chem Soc ; 145(5): 2911-2929, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36715296

RESUMO

Catalysts for hydroformylation of ethene were prepared by grafting Rh into nests of ≡SiOZn-OH or ≡SiOCo-OH species prepared in dealuminated BEA zeolite. X-ray absorption spectra and infrared spectra of adsorbed CO were used to characterize the dispersion of Rh. The Rh dispersion was found to increase markedly with increasing M/Rh (M = Zn or Co) ratio; further increases in Rh dispersion occurred upon use for ethene hydroformylation catalysis. The turnover frequency for ethene hydroformylation measured for a fixed set of reaction conditions increased with the fraction of atomically dispersed Rh. The ethene hydroformylation activity is 15.5-fold higher for M = Co than for M = Zn, whereas the propanal selectivity is slightly greater for the latter catalyst. The activity of the Co-containing catalyst exceeds that of all previously reported Rh-containing bimetallic catalysts. The rates of ethene hydroformylation and ethene hydrogenation exhibit positive reaction orders in ethene and hydrogen but negative orders in carbon monoxide. In situ IR spectroscopy and the kinetics of the catalytic reactions suggest that ethene hydroformylation is mainly catalyzed by atomically dispersed Rh that is influenced by Rh-M interactions, whereas ethene hydrogenation is mainly catalyzed by Rh nanoclusters. In situ IR spectroscopy also indicates that the ethene hydroformylation is rate limited by formation of propionyl groups and by their hydrogenation, a conclusion supported by the measured H/D kinetic isotope effect. This study presents a novel method for creating highly active Rh-containing bimetallic sites for ethene hydroformylation and provides new insights into the mechanism and kinetics of this process.

3.
Small ; 19(26): e2207272, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36942900

RESUMO

Atomically dispersed metal catalysts offer the advantages of efficient metal utilization and high selectivities for reactions of technological importance. Such catalysts have been suggested to be strong candidates for dry reforming of methane (DRM), offering prospects of high selectivity for synthesis gas without coke formation, which requires ensembles of metal sites and is a challenge to overcome in DRM catalysis. However, investigations of the structures of isolated metal sites on metal oxide supports under DRM conditions are lacking, and the catalytically active sites remain undetermined. Data characterizing the DRM reaction-driven structural evolution of a cerium oxide-supported catalyst, initially incorporating atomically dispersed platinum, and the corresponding changes in catalyst performance are reported. X-ray absorption and infrared spectra show that the reduction and agglomeration of isolated cationic platinum atoms to form small platinum clusters/nanoparticles are necessary for DRM activity. Density functional theory calculations of the energy barriers for methane dissociation on atomically dispersed platinum and on platinum clusters support these observations. The results emphasize the need for in-operando experiments to assess the active sites in such catalysts. The inferences about the catalytically active species are suggested to pertain to a broad class of catalytic conversions involving the rate-limiting dissociation of light alkanes.

4.
PLoS Pathog ; 17(2): e1009343, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33630975

RESUMO

The outcome of Leishmania donovani infection depends upon the dynamic interchanges between M1 and M2 macrophages. Information of the involvement of microRNAs (miRNAs) and epigenetic modifiers in regulating macrophage plasticity during L. donovani infection is still elusive. Differential expression analysis of polarization-regulating miRNAs, revealed significant enrichment of miR146a-5p during Leishmania donovani infection. A sustained enrichment of miR146a-5p was observed in both infected bone marrow derived macrophages (BMDMs) and BALB/c mice organs. We found involvement of miR146a-5p in phagocytosis and survivability of parasites. Moreover, miR146a-5pgot enriched in interleukin 4- stimulated BMDMs, indicating its possible involvement in M2 polarization. Upon transfecting BMDMs with miRVANA anti-146a oligos, M2 markers (CCR7, YM-1, FIZZ-1, arginase-1, IL10 and IL4) and transcription factors (p-STAT6 and c/EBPß) got depleted with concomitant augmentation of M1-polarizing transcription factors (p-STAT1, AP1 and IRF-1), miR146a target genes (TRAF6 and IRAK1), M1 cytokines (IL12 and TNFα), iNOS, nitric oxide, and nuclear translocation of phospho p-65 subunit. Neutralization of intracellular mature miR146a-5p pool in infected BALB/c mice lower organ parasite burden and expressions of M2 markers and IL10 with enrichment of M1 markers like iNOS and IL12. Additionally, we explored the novel role of super enhancer (SE), a cis-acting regulatory component, to enrich miR146a-5p expression during infection. Enhanced expression and nuclear retention of SE components like BET bromodomain 4 (BRD4) and p300 were found in infected BMDMs. Upon silencing BRD4, expressions of miR146a-5p and M2 markers were down regulated and TRAF6, IRAK1 and iNOS levels increased. STRING V.11 based predication and immune precipitation confirmed the strong interaction amongst BRD4, p300 and RNA pol II (RpbI). Chromatin immune precipitation studies suggested the recruitment of BRD4 at the enhancer loci of miR146a-5p gene during infection. Altogether, our findings revealed a novel role of BRD4/p300-depdendent super-enhancer in regulating miR146a expression during L. donovani infection which in turn mediates M2 polarization and immune-suppression.


Assuntos
Elementos Facilitadores Genéticos , Leishmania donovani/fisiologia , Leishmaniose/imunologia , Macrófagos/imunologia , MicroRNAs/genética , Fagocitose , Animais , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Leishmaniose/genética , Leishmaniose/metabolismo , Leishmaniose/parasitologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/metabolismo
5.
FASEB J ; 35(9): e21755, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383962

RESUMO

Visceral leishmaniasis (VL) is a debilitating human pathogenesis in which the body's immune functions are severely compromised. Various subsets of T cells, including Th17 cells are important regulators of immune responses observed in various pathologies. The role of Th17 cells and its correlation with immuno-regulatory cytokines are however not well understood in human VL. Herein we studied how IL-17 is associated with the progression of Leishmania donovani infection using murine model of VL. We found induction of a strong IL-17 response at the early phase of infection which progressively reduced to basal level during chronic VL. The mechanistic study of this behavior was found to be linked with the role of regulatory T cells (CD4+ CD25+ T cells) that suppresses the proliferation of the Th17 cell population. Moreover, TGF-ß and IL-35 derived from CD4+ CD25+ T cells are the key mediators for the downregulation of IL-17 during chronic VL. Thus, this study points to an antagonistic effect of Tregs and Th17 cells that can be used for designing better therapeutic and preventive strategies against leishmaniasis.


Assuntos
Interleucinas/imunologia , Leishmaniose Visceral/imunologia , Células Th17/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/parasitologia , Células Cultivadas , Subunidade alfa de Receptor de Interleucina-2/imunologia , Leishmania donovani/parasitologia , Leishmaniose Visceral/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Células Th17/parasitologia
6.
J Biol Chem ; 295(29): 9934-9947, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32471865

RESUMO

The emergence of resistance to available antileishmanial drugs advocates identification of new drug targets and their inhibitors for visceral leishmaniasis. Here, we identified Leishmania donovani heat shock protein 78 (LdHSP78), a putative caseinolytic protease, as important for parasite infection of host macrophages and a potential therapeutic target. Enrichment of LdHSP78 in infected humans, hamsters, and parasite amastigotes suggested its importance for disease persistence. Heterozygous knockouts of L. donovani HSP78 (LdHSP78+/-) and Leishmania mexicana HSP78 (LmxHSP78+/-) were generated using a flanking UTR-based multifragment ligation strategy and the CRISPR-Cas9 technique, respectively to investigate the significance of HSP78 for disease manifestation. The LdHSP78+/- parasite burden was dramatically reduced in both murine bone marrow-derived macrophages and hamsters, in association with enrichment of proinflammatory cytokines and NO. This finding implies that LdHSP78+/- parasites cannot suppress immune activation and escape NO-mediated toxicity in macrophages. Furthermore, phosphorylation of the mitogen-activated protein kinase p38 was enhanced and phosphorylation of extracellular signal-regulated kinase 1/2 was decreased in cells infected with LdHSP78+/- parasites, compared with WT parasites. Virulence of the LdHSP78+/- strain was restored by episomal addition of the LdHSP78 gene. Finally, using high-throughput virtual screening, we identified P1,P5-di(adenosine-5')-pentaphosphate (Ap5A) ammonium salt as an LdHSP78 inhibitor. It selectively induced amastigote death at doses similar to amphotericin B doses, while exhibiting much less cytotoxicity to healthy macrophages than amphotericin B. In summary, using both a genetic knockout approach and pharmacological inhibition, we establish LdHSP78 as a drug target and Ap5A as a potential lead for improved antileishmanial agents.


Assuntos
Antiprotozoários/farmacologia , Fosfatos de Dinucleosídeos/farmacologia , Proteínas de Choque Térmico/antagonistas & inibidores , Leishmania donovani/metabolismo , Leishmaniose Visceral/tratamento farmacológico , Macrófagos/parasitologia , Proteínas de Protozoários/antagonistas & inibidores , Animais , Sistemas CRISPR-Cas , Cricetinae , Técnicas de Inativação de Genes , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Leishmania donovani/genética , Leishmaniose Visceral/genética , Leishmaniose Visceral/metabolismo , Macrófagos/metabolismo , Camundongos , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
7.
Chem Soc Rev ; 49(10): 2937-3004, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32407432

RESUMO

Catalytic conversion of CO2 to produce fuels and chemicals is attractive in prospect because it provides an alternative to fossil feedstocks and the benefit of converting and cycling the greenhouse gas CO2 on a large scale. In today's technology, CO2 is converted into hydrocarbon fuels in Fischer-Tropsch synthesis via the water gas shift reaction, but processes for direct conversion of CO2 to fuels and chemicals such as methane, methanol, and C2+ hydrocarbons or syngas are still far from large-scale applications because of processing challenges that may be best addressed by the discovery of improved catalysts-those with enhanced activity, selectivity, and stability. Core-shell structured catalysts are a relatively new class of nanomaterials that allow a controlled integration of the functions of complementary materials with optimised compositions and morphologies. For CO2 conversion, core-shell catalysts can provide distinctive advantages by addressing challenges such as catalyst sintering and activity loss in CO2 reforming processes, insufficient product selectivity in thermocatalytic CO2 hydrogenation, and low efficiency and selectivity in photocatalytic and electrocatalytic CO2 hydrogenation. In the preceding decade, substantial progress has been made in the synthesis, characterization, and evaluation of core-shell catalysts for such potential applications. Nonetheless, challenges remain in the discovery of inexpensive, robust, regenerable catalysts in this class. This review provides an in-depth assessment of these materials for the thermocatalytic, photocatalytic, and electrocatalytic conversion of CO2 into synthesis gas and valuable hydrocarbons.

8.
Int Immunol ; 28(12): 585-595, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28013190

RESUMO

Leishmania donovani resides within the host macrophages by dampening host defence mechanisms and thereby it modulates the host cell functions for its survival. Multiple host cell factors compete during the interplay between the host and the parasite. Roles for dual-specificity phosphatases (DUSPs) are implicated in various pathological conditions. However, the reciprocity of these DUSPs was unknown in L. donovani infection in a susceptible model. Here, we show that Mycobacterium indicus pranii (Mw), an immunomodulator, reciprocally regulates DUSP1 and DUSP6 through the TLR4 pathway. Association of PKC-ß with DUSP6 increases after Mw treatment resulting in decreased IL-10, phosphorylation of ERK1/2 and Arginase-1, whereas Mw treatment decreases the association between PKC-ε and DUSP1 resulting in increased IL-12, phosphorylation of p38 and inducible nitric oxide synthase expression. Silencing of DUSP1 or over-expression of DUSP6 in L. donovani-infected BALB/c mice decreases the parasite burden by inducing IL-12 and reducing IL-10 production. Therefore, we identify DUSP1 and DUSP6 as therapeutic targets, functions of which could be favourably modulated by Mw during L. donovani infection.


Assuntos
Fatores Imunológicos/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Mycobacterium/imunologia , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Camundongos , Camundongos Endogâmicos BALB C , Monoéster Fosfórico Hidrolases/imunologia , Especificidade da Espécie , Especificidade por Substrato
9.
Chemphyschem ; 18(22): 3117-3134, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-28710875

RESUMO

In recent years, CO2 reforming of methane (dry reforming of methane, DRM) has become an attractive research area because it converts two major greenhouse gasses into syngas (CO and H2 ), which can be directly used as fuel or feedstock for the chemical industry. Ni-based catalysts have been extensively used for DRM because of its low cost and good activity. A major concern with Ni-based catalysts in DRM is severe carbon deposition leading to catalyst deactivation, and a lot of effort has been put into the design and synthesis of stable Ni catalysts with high carbon resistance. One effective and practical strategy is to introduce a second metal to obtain bimetallic Ni-based catalysts. The synergistic effect between Ni and the second metal has been shown to increase the carbon resistance of the catalyst significantly. In this review, a detailed discussion on the development of bimetallic Ni-based catalysts for DRM including nickel alloyed with noble metals (Pt, Ru, Ir etc.) and transition metals (Co, Fe, Cu) is presented. Special emphasis has been provided on the underlying principles that lead to synergistic effects and enhance catalyst performance. Finally, an outlook is presented for the future development of Ni-based bimetallic catalysts.

10.
Phys Chem Chem Phys ; 19(20): 12838-12844, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28470288

RESUMO

Herein, we report the fabrication of flexible solar cells based on a crystalline p-Si/n-ZnO heterostructure for the first time. An enhancement of ∼52% in the base efficiency was achieved by the application of spherical SiO2 nanoparticles as light trapping structures on the top. The use of ZnO not only offers a facile route of synthesis, but also provides an additional advantage of large band bending, leading to notable open circuit voltage and formation of an intermediate ultra-thin barrier layer of Zn2SiO4 for minimized carrier recombination. The spherical silica nanoparticles act as nanoresonators, causing absorption hot-spots in the thin silicon absorber, along with the capability of providing wide-angle light-collection. Simulation showed, for the higher angle of incidence, that the silica nanoparticles have the ability to bend light on the same side of the normal to the incident wave-front, thereby acting as a negative index metamaterial (NIM). The flexibility and cost-effectiveness of this device can make it important for the next-generation photovoltaics and roll-to-roll electronics.

11.
Nanotechnology ; 27(30): 305302, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27319809

RESUMO

Analysis and optimization of silicon nano-structured geometry (black silicon) for photovoltaic applications has been reported. It is seen that a unique class of geometry: micro-nanostructure has the potential to find a balance between the conflicting interests of reduced reflection for wide angles of incidence, reduced surface area enhancement due to the nano-structuring of the substrate and reduced material wastage due to the etching of the silicon substrate to realize the geometry itself. It is established that even optimally designed micro-nanostructures would not be useful for conventional wafer based approaches. The work presents computational studies on how such micro-nanostructures are more potent for future ultra-thin monocrystalline silicon absorbers. For such ultra-thin absorbers, the optimally designed micro-nanostructures provide additional advantages of advanced light management capabilities as it behaves as a lossy 2D photonic crystal making the physically thin absorber optically thick along with the ability to collect photo-generated carriers orthogonal to the direction of light (radial junction) for unified photon-electron harvesting. Most significantly, the work answers the key question on how thin the monocrystalline solar absorber should be so that optimum micro-nanostructure would be able to harness the incident photons ensuring proper collection so as to reach the well-known Shockley-Queisser limit of solar cells. Flexible ultra-thin monocrystalline silicon solar cells have been fabricated using nanosphere lithography and MacEtch technique along with a synergistic association of crystalline and amorphous silicon technologies to demonstrate its physical and technological flexibilities. The outcomes are relevant so that nanotechnology may be seamlessly integrated into the technology roadmap of monocrystalline silicon solar cells as the silicon thickness should be significantly reduced without compromising the efficiency within the next decade.

12.
J Orthop Case Rep ; 14(7): 93-97, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39035394

RESUMO

Introduction: Securing stable internal fixation for fractures in osteoporotic intra-articular distal femur proves to be a demanding task due to thin cortices, a wide medullary canal, diminished bone stock, and fracture comminution. No singular therapeutic approach has successfully tackled all facets of this injury. Consequently, we now introduce a pioneering fixation method in our report, aiming to offer a holistic solution to the intricate challenges associated with this scenario. Case Report: A 60-year-old female presented with an intra-articular distal femur fracture, and underwent a combination fixation of distal femur plate and intramedullary interlocking nailing. The patient was rehabilitated with active knee range of motion on post-operative day 7 and has now attained full knee range of motion. Conclusion: The utilization of anatomical plates with locking mechanisms, in tandem with intramedullary interlocking nailing, holds promise for the secure stabilization and fixation of osteoporotic distal femur fractures, potentially leading to an expedited recovery process.

13.
J Orthop Case Rep ; 14(3): 78-82, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38560300

RESUMO

Introduction: The femoral neck system (FNS) represents an emerging fixation system designed for the management of femoral neck fractures. This innovative system combines the mechanical benefits of compression and anti-rotation properties in internal fixation. Biomechanical studies have demonstrated the superior axial and rotational stability of the FNS implant when compared to traditional cannulated screws and dynamic hip screw. Despite these promising mechanical advantages, there is currently a limited body of literature addressing the factors contributing to FNS failure. A thorough assessment of the safety and outcomes associated with this novel implant is essential. Case Report: In this context, we present three cases wherein FNS failure occurred, aiming to elucidate the potential causes behind these failures, and had to undergo either an implant removal or bipolar hemiarthroplasty. Conclusion: While considering the femoral neck system as the implant of choice, we should consider the age, injury to surgery time, and the location of the fracture line. However, we cannot conclusively ascertain whether age contributes independently to the risk of failure.

14.
Antimicrob Agents Chemother ; 57(3): 1246-51, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23262997

RESUMO

Plasmodium vivax malaria, though benign, has now become a matter of concern due to recent reports of life-threatening severity and development of parasite resistance to different antimalarial drugs. The magnitude of the problem is still undetermined. The present study was undertaken to determine the in vivo efficacy of chloroquine (CQ) and chloroquine plus primaquine in P. vivax malaria in Kolkata and polymorphisms in the pvmdr1 and pvcrt-o genes. A total of 250 patients with P. vivax monoinfection were recruited and randomized into two groups, A and B; treated with chloroquine and chloroquine plus primaquine, respectively; and followed up for 42 days according to the WHO protocol of 2009. Data were analyzed using per-protocol analyses. We assessed polymorphisms of the pvmdr1 and pvcrt-o genes by a DNA-sequencing method. Out of the 250 patients recruited, 204 completed a 42-day follow-up period, 101 in group A and 103 in group B. In group A, the non-PCR-corrected efficacy of CQ was 99% (95% confidence interval [CI], 0.944 to 1.00), and in group B, all cases were classified as adequate clinical and parasitological response (ACPR). Day 3 positivity was observed in 11 (5.3%) cases. No specific mutation pattern was recorded in the pvcrt-o gene. Eight nonsynonymous mutations were found in the pvmdr1 gene, three of which were new. The Y976F mutation was not detected in any isolate. Chloroquine, either alone or in combination with primaquine, is still effective against P. vivax malaria in the study area. (The study protocol was registered in CTRI [Clinical Trial Registry-India] of the Indian council of Medical Research under registration no. CTRI/2011/09/002031.).


Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Malária Vivax/tratamento farmacológico , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium vivax/genética , Polimorfismo Genético , Primaquina/uso terapêutico , Proteínas de Protozoários/genética , Adolescente , Adulto , Idoso , Antimaláricos/farmacologia , Criança , Pré-Escolar , Cloroquina/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Índia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Mutação , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Primaquina/farmacologia , Resultado do Tratamento
15.
J Clin Microbiol ; 51(5): 1439-44, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23426929

RESUMO

Asymptomatic infection by Plasmodium falciparum is an important obstacle to eliminating malaria. Asymptomatic carriers do not seek treatment for infection, and therefore they become a reservoir for the parasite. For this reason, these carriers pose a real public health risk. The systematic identification and treatment of asymptomatic infections should reduce the parasite reservoir. A large reduction in this pool will lower the chance of transmission of the disease. In this study, we screened a tribal population of 1,040 individuals in the Purulia district of West Bengal by using a dual-antigen rapid diagnostic kit (RDK), microscopy, and species-specific PCR. All positive individuals were treated with artemisinin-based combination therapy (ACT) (artesunate plus sulfadoxine-pyrimethamine) and followed for 42 days. Polymorphisms in candidate genes were screened by DNA sequencing. A significant proportion (8.4%) of the study population was infected with P. falciparum but showed no clinical manifestations. The PCR method was more sensitive in detecting infection than the RDK or microscopy. The efficacy of the ACT was 97%. In the pfcrt gene, the mutation K76T (the mutated amino acid is indicated by bold type) was found in 100% of the cases. In the pfmdr1 gene, the mutations N86Y and Y184F were noted in 55.5% and 11% of the cases, respectively. Six different haplotypes were identified in the pfdhfr-pfdhps genes. Most importantly, the quintuple mutant A(16)I(51)R(59)N(108)I(164)-S(436)G(437)E(540)A(581)A(613) was found in 10% of the isolates, which is potentially important for the development of sulfadoxine-pyrimethamine resistance. A significant proportion of the study population harboring P. falciparum does not seek treatment and therefore serves as a reservoir for the parasite, maintaining the natural cycle. If the National Vector Borne Disease Control Programme (NVBDCP) of India is to eliminate malaria, then this hidden parasite burden needs to be addressed properly. Similar study in other parts of the country could help to determine the magnitude of the problem.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Infecções Assintomáticas/epidemiologia , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Plasmodium falciparum/classificação , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Sequência de Bases , Combinação de Medicamentos , Resistência a Medicamentos , Genótipo , Humanos , Índia/epidemiologia , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/genética , Polimorfismo de Nucleotídeo Único , Grupos Populacionais , Prevalência , Proteínas de Protozoários/genética , Análise de Sequência de DNA
16.
Pharm Biol ; 51(6): 677-85, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23527893

RESUMO

CONTEXT: Scientific validation of an ethnomedicinal combination consisting of Semecarpus kurzii Engler (Anacardeaceae) leaves (SKL) and Hernandia peltata Meisn (Hernandeaceae) stem-bark (HPB), traditionally used in ailments related to inflammation, pain and fever. OBJECTIVE: To validate in vivo and in vitro analgesic and antiinflammatory activities of methanol extract of SKL, HPB and their combination. MATERIALS AND METHODS: Analgesic activity was tested by acetic acid induced writhing reflex and tail flick in Swiss albino mice, while the anti-inflammatory activity was studied in acute, subacute and chronic model on Wistar rats. The vascular permeability, membrane stabilization and protein denaturation were examined to know the possible mode of action. RESULTS: Significant (p < 0.01) analgesic (78.04% inhibition of writhing) and antiinflammatory (72.54% inhibition of paw edema) activity was observed in combination of SKL and HPB extracts at 250 mg/kg each. The SKL extract alone inhibits acetic acid-induced vascular permeability (64.4%) at 500 mg/kg, while in combination at 250 mg/kg each, the inhibition was 69.49% (p < 0.01). Furthermore, SKL in combination with HPB (0.25 mg/mL each) prevent RBC hemolysis (61.91%) and inhibition of protein denaturation (76.52%)-like indomethacin. DISCUSSION AND CONCLUSION: The SKL and HPB extract, alone (500 mg/kg) and in combination, (250 mg/kg each) had significant analgesic and antiinflammatory activity, probably by inhibiting the release of certain inflammatory mediators and membrane stabilization, due to the presence of triterpenes, tannins and related phytochemicals in the extracts. Thus, our results demonstrated that this combination provide the scientific rationale of its folk use.


Assuntos
Hernandiaceae/química , Extratos Vegetais/farmacologia , Semecarpus/química , Dor Aguda/tratamento farmacológico , Analgésicos/administração & dosagem , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Dor Crônica/tratamento farmacológico , Modelos Animais de Doenças , Quimioterapia Combinada , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Masculino , Medicina Tradicional , Camundongos , Casca de Planta , Extratos Vegetais/administração & dosagem , Folhas de Planta , Caules de Planta , Ratos , Ratos Wistar
17.
STAR Protoc ; 4(1): 102004, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36638018

RESUMO

Isolation of extraordinarily long-length super-enhancers (SEs) using typical chromatin immune precipitation (ChIP) techniques can lead to DNA breakage due to uncontrolled cross-linking. We present a redefined ChIP technique for SE purification. After controlled paraformaldehyde-based cross-linking, glycine was used to quench the cross-linker followed by mild sonication. The sonication produced ideal fragment length of long-length SE chromatin. Presently, miR146a-5p SE of macrophages was pulled using BRD4 protein. Our protocol can reproducibly simplify the SE element isolation issues, in a quality-controlled manner. For complete details on the use and execution of this protocol, please refer to Das et al. (2021).1.


Assuntos
Proteínas Nucleares , Fatores de Transcrição , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Cromatina/genética , Macrófagos/metabolismo , Elementos Facilitadores Genéticos , Imunoprecipitação
18.
Front Cell Infect Microbiol ; 13: 1001973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814446

RESUMO

Leishmania is an intracellular, zoonotic, kinetoplastid eukaryote with more than 1.2 million cases all over the world. The leishmanial chromosomes are divided into polymorphic chromosomal ends, conserved central domains, and antigen-encoding genes found in telomere-proximal regions. The genome flexibility of chromosomal ends of the leishmanial parasite is known to cause drug resistance and intracellular survival through the evasion of host defense mechanisms. Therefore, in this review, we discuss the plasticity of Leishmania genome organization which is the primary cause of drug resistance and parasite survival. Moreover, we have not only elucidated the causes of such genome plasticity which includes aneuploidy, epigenetic factors, copy number variation (CNV), and post-translation modification (PTM) but also highlighted their impact on drug resistance and parasite survival.


Assuntos
Leishmania donovani , Parasitos , Animais , Leishmania donovani/genética , Variações do Número de Cópias de DNA , Resistência a Medicamentos , Percepção
19.
JACS Au ; 3(3): 785-800, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37006774

RESUMO

The removal of tar and CO2 in syngas from biomass gasification is crucial for the upgrading and utilization of syngas. CO2 reforming of tar (CRT) is a potential solution which simultaneously converts the undesirable tar and CO2 to syngas. In this study, a hybrid dielectric barrier discharge (DBD) plasma-catalytic system was developed for the CO2 reforming of toluene, a model tar compound, at a low temperature (∼200 °C) and ambient pressure. Periclase-phase (Mg, Al)O x nanosheet-supported NiFe alloy catalysts with various Ni/Fe ratios were synthesized from ultrathin Ni-Fe-Mg-Al hydrotalcite precursors and employed in the plasma-catalytic CRT reaction. The result demonstrated that the plasma-catalytic system is promising in promoting the low-temperature CRT reaction by generating synergy between DBD plasma and the catalyst. Among the various catalysts, Ni4Fe1-R exhibited superior activity and stability because of its highest specific surface area, which not only provided sufficient active sites for the adsorption of reactants and intermediates but also enhanced the electric field in the plasma. Furthermore, the stronger lattice distortion of Ni4Fe1-R provided more isolated O2- for CO2 adsorption, and having the most intensive interaction between Ni and Fe in Ni4Fe1-R restrained the catalyst deactivation induced by the segregation of Fe from the alloy to form FeO x . Finally, in situ Fourier transform infrared spectroscopy combined with comprehensive catalyst characterization was used to elucidate the reaction mechanism of the plasma-catalytic CRT reaction and gain new insights into the plasma-catalyst interfacial effect.

20.
J Med Chem ; 66(5): 3411-3430, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36823782

RESUMO

The unique bisubunit structure of Leishmania donovani topoisomerase 1B (LdTop1) is a potential drug target in the parasites unlike the monomeric Top1 from its human host counterpart. Here, we report the design, synthesis, and validation of a chimeric pyrido[2',1':2,3]imidazo[4,5-c]quinoline derivative (C17) as a novel antileishmanial agent that poisons topoisomerase 1-DNA covalent complexes (LdTop1cc) inside the parasites and inhibits Top1 religation activity both in the drug sensitive and antimony-resistant L. donovani clinical isolates. Importantly, the human Top1 is not sensitive to C17. Further, C17 overcomes the chemical instability of camptothecin (CPT) by generating persistent LdTop1cc-induced DNA breaks inside the parasites even after 12 h of drug removal. Intraperitoneal administration of C17 results in marked reduction of the Leishmania amastigotes from the infected spleen and liver of BALB/c mice. C17 confers a host protective immune-response up-regulating the Th1 cytokines facilitating parasite clearance which can be exploited for treating drug-resistant leishmaniasis.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Leishmaniose , Venenos , Quinolinas , Animais , Camundongos , Humanos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Antimônio/farmacologia , Antimônio/uso terapêutico , Venenos/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose/tratamento farmacológico , DNA/química , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Camundongos Endogâmicos BALB C
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