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1.
Heliyon ; 10(9): e30263, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726148

RESUMO

Advanced graphene-based materials have been proficiently incorporated into next-generation solar cells and supercapacitors because of their high electrical conductivity, large surface area, excellent charge-transport ability, and exceptional optical properties. Herein, we report the synthesis of graphene nanosheets (GNs) from waste cardboard via pyrolysis, with ethyl alcohol as the growth initiator. Additionally, we demonstrated the use of GNs in energy conversion and storage applications. Using the GN electrode in perovskite solar cells resulted in an excellent power conversion efficiency of ∼10.41 % for an active area of 1 cm2, indicating an enhancement of approximately 27 % compared to conventional electrodes. Furthermore, the GNs were used as active electrode materials in supercapacitors with excellent electrochemical performance and a high gravimetric specific capacitance of 167.5 F/g at a scan rate of 2 mV/s. The developed GNs can be efficiently used for energy storage, conversion, and electrochemical sensing applications.

3.
Asian J Psychiatr ; 56: 102521, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421694

RESUMO

The present study examined India's publications (2803) on schizophrenia, using various bibliometric indicators during 1990-2019. The study focuses on the number of publications, and citations received by the papers on schizophrenia, published by authors affiliated to Indian institutes by using Scopus data base. Additionally, an attempt was made to evaluate the performance of India's leading organizations and authors, and inter-collaborative linkages between them. Scopus database include publications of Indian Journal of Psychiatry and Indian Journal of Psychological Medicine from 2009 and 2011. Accordingly, the publications in these journals were included after these years. Analysis of the publications showed that India is globally ranked at 13th position in number of publications on schizophrenia with 2.04 % global share, depicting 14.21 % annual growth, with 22.8 % of publications having international collaboration. Publications from India published during the period of 1990-2019, registered a citation impact per paper (CPP) of 13.3. National Institute of Mental Health and Neurosciences, Bangalore (671 papers), Post Graduate Institute of Medical Education and Research, Chandigarh (271 papers) and Central Instittue of Psychiatry, Ranchi (136 papers) were the most productive institutes. However, the most impactful organizations in terms of citation per paper (CPP) and relative citation index (RCI), Indian Institute of Science, Bangalore (77.27 CPP and 5.78 RCI), Schizophrenia Research Foundation, Chennai (31.16 CPP and 2.55 RCI) and Banaras Hindu University, Varanasi (29.21 CPP and 2.18 RCI) were at the top. In terms of Individual authors, G. Venkatasubramanian (180 papers), and B.N. Gangadhar (162 papers) were the most productive authors and R.Thara (31.87 CPP and 2.38 RCI), B.K. Thelma (24.0 CPP and 1.8 RCI), M.S. Keshavan (23.91 CPP and 1.79 RCI) were the most impactful authors, among the top 15 authors. The journals which reported comparatively higher productivity for Indian publications included Indian Journal of Psychiatry (242 papers), followed by Asian Journal of Psychiatry (214 papers) and Indian Journal of Psychological Medicine (103 papers). In terms of most impactful Indian publications, these were published in The Lancet (97.7), Progress in Neuro Psychopharmacology & Biological Psychiatry (50) and Schizophrenia Bulletin (44.67).


Assuntos
Pesquisa Biomédica , Esquizofrenia , Bibliometria , Humanos , Índia , Publicações , Esquizofrenia/terapia
4.
Asian J Psychiatr ; 55: 102532, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33360705

RESUMO

The paper examines 1037 publications on bipolar disorder (BD) during the years 2000-19 from India, as listed in the Scopus database. India's publications constituted 2.27 % share of global output (45,624 publications) in the study period of 20 years. India does not figure in the top 10 countries in terms of research output on BD. The number of publications on BD from India increased from 13 in 2000 to 107 in 2019, registering 14.44 % annual average growth, higher than world's growth of 6.02 %. India's 10-year cumulative publications increased from 264 during 2000-09 to 773 during 2010-19, registering 192.8 % absolute growth, much higher than world cumulative growth of 63.27 %. India's publications on BD averaged citation impact per paper of 14.24, which decreased from 25.38 to 10.43 from 2000-09 to 2010-19. Maximum numbers of papers from India on BD were published by researchers from National Institute of Mental Health and Neurosciences, Bangalore (222 papers),Post Graduate Institute of Medical Education and Research, Chandigarh(118 papers), and AII India Institute of Medical Sciences, New Delhi (79 papers). Lady Harding Medical College, New Delhi (36.20 and 2.54), Schizophrenia Research Foundation, Chennai (27.45 and 1.93), and King George's Medical University, Lucknow (25.21 and 1.77) were the most significant organizations in terms of citation per paper and relative citation index. Maximum number of papers were published in Indian Journal of Psychiatry (101 papers), followed by Asian Journal of Psychiatry (88 papers) and Indian Journal of Psychology Medicine (34 papers).


Assuntos
Pesquisa Biomédica , Transtorno Bipolar , Neurociências , Bibliometria , Humanos , Índia , Publicações
5.
Br J Dermatol ; 183(3): 471-479, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31907924

RESUMO

BACKGROUND: Papulopustular rosacea is characterized by chronic facial erythema and inflammatory facial lesions. Minocycline has anti-inflammatory properties which may be effective in the treatment of rosacea inflammatory lesions. OBJECTIVES: To assess the safety and efficacy of once-daily topical minocycline gel 1% and 3% in patients with papulopustular rosacea. METHODS: This was a prospective, 12-week, double-blinded study conducted at 26 sites in the United States; 270 patients with papulopustular rosacea and 12-40 inflammatory lesions were randomized to minocycline 1%, minocycline 3% or vehicle. The primary endpoint was the mean change in inflammatory lesions at week 12. Key secondary endpoints included success on an Investigator's Global Assessment (IGA). RESULTS: Baseline mean lesion counts were 24·6, 25·1 and 24·3 in the minocycline 1%, minocycline 3% and vehicle groups, respectively; at week 12, the counts had decreased by 12·6, 13·1 and 7·9, respectively. Minocycline significantly decreased lesions, compared with the vehicle [P = 0·01, 95% confidence interval (CI) 7·9 to 0·9, for minocycline 1%; P = 0·007, 95% CI 8·3 to 1·3, for minocycline 3%]. The proportion of patients achieving IGA success was 39% in the minocycline 1% arm [P = 0·34, odds ratio (OR) 1·396 and OR 95% CI 0·71 to 2·75 vs. vehicle], 46% in the minocycline 3% arm (P = 0·04, OR 2·03 and OR 95% CI 1·04 to 3·95 vs. vehicle) and 31% in the vehicle arm. CONCLUSIONS: Minocycline topical gel appears to be safe and tolerable at concentrations of 1% and 3%, and both concentrations significantly decreased inflammatory lesion counts, with a significantly larger proportion of patients achieving IGA success at week 12 in the minocycline 3% arm. These findings support further evaluation of minocycline gel for treating inflammatory lesions associated with papulopustular rosacea. Linked Comment: Hampton. Br J Dermatol 2020; 183:412-413.


Assuntos
Fármacos Dermatológicos , Rosácea , Administração Cutânea , Fármacos Dermatológicos/efeitos adversos , Método Duplo-Cego , Humanos , Minociclina/efeitos adversos , Estudos Prospectivos , Rosácea/tratamento farmacológico , Resultado do Tratamento , Estados Unidos
7.
Br J Dermatol ; 181(4): 733-742, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30919407

RESUMO

BACKGROUND: ASN002 is an oral dual inhibitor of Janus kinase and spleen tyrosine kinase, which are involved in the pathogenesis of atopic dermatitis (AD) through their regulatory role on T helper (Th)1, Th2 and Th17/Th22 pathways. OBJECTIVES: The objectives of this study were to evaluate the efficacy, safety, pharmacokinetics and effects on systemic biomarkers of ASN002 in patients with moderate-to-severe AD. Methods A total of 36 patients with moderate-to-severe AD were randomized (3 : 1) to ASN002 or placebo in the phase Ib study. Three dosage cohorts were studied over a 28-day period (20 mg, 40 mg and 80 mg once daily). RESULTS: ASN002 was superior to placebo for the proportion of patients achieving Eczema Area and Severity Index (EASI) 50 (20 mg 20%, P = 0·93; 40 mg 100%, P = 0·003; 80 mg 83%, P = 0·03; placebo 22%), EASI 75 (20 mg 0%, P = 0·27; 40 mg 71%, P = 0·06; 80 mg 33%, P = 0·65; placebo 22%) and in change from baseline in pruritus (20 mg -1·3 ± 2·1, P = 0·81; 40 mg -3·1 ± 2·7, P = 0·27; 80 mg -4·7 ± 2·1, P = 0·01; placebo -1·6 ± 1·8). Adverse events were generally mild and similar across all groups. ASN002 showed dose-dependent plasma exposure with low interpatient variability, significantly downregulated several serum biomarkers involved in Th1, Th2 and Th17/Th22 immunity, and decreased the atherosclerosis-associated biomarker E selectin/SELE. CONCLUSIONS: In patients with moderate-to-severe AD, ASN002 showed strong efficacy with rapid onset of action and associated improvements in systemic inflammation.


Assuntos
Acetonitrilas/administração & dosagem , Dermatite Atópica/tratamento farmacológico , Inibidores de Janus Quinases/administração & dosagem , Piperidinas/administração & dosagem , Piridazinas/administração & dosagem , Acetonitrilas/efeitos adversos , Acetonitrilas/farmacocinética , Adulto , Biomarcadores/sangue , Dermatite Atópica/sangue , Dermatite Atópica/diagnóstico , Dermatite Atópica/imunologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Selectina E/sangue , Feminino , Humanos , Inibidores de Janus Quinases/efeitos adversos , Inibidores de Janus Quinases/farmacocinética , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo , Masculino , Pessoa de Meia-Idade , Piperidinas/efeitos adversos , Piperidinas/farmacocinética , Placebos/administração & dosagem , Placebos/efeitos adversos , Piridazinas/efeitos adversos , Piridazinas/farmacocinética , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Quinase Syk/antagonistas & inibidores , Quinase Syk/metabolismo , Resultado do Tratamento , Adulto Jovem
8.
J Assoc Physicians India ; 66(12): 11-12, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31313548

RESUMO

OBJECTIVE: Triple drug combination has shown to be effective in controlling blood pressure (BP) with low rates of drug-related side effects. The present study was conducted to compare the efficacy and safety of a triple pill of telmisartan/amlodipine/hydrochlorothiazide (HCTZ) with a dual combination of telmisartan/HCTZ in treating hypertensive patients who did not respond to monotherapies. METHODS: A total of 512 patients were randomized to receive either low-dose triple pill or the dual combination therapy. The primary endpoint was BP normalization after 8 weeks. The secondary endpoints were BP normalization at 4 weeks, changes in BP from baseline to Week 8, comparison of BP normalization between treatment groups, and difference in BP responder rates. The analysis was conducted on the intent-to-treat (ITT), modified intent-to-treat (mITT) and per protocol (PP) population. RESULTS: Statistically significant difference was noted between triple pill and telmi+HCTZ in the normalization of BP at Week 8 in the mITT (p=0.041) and PP (p=0. 038) populations. Also, a statistically significant improvement was observed in BP normalization in triple pill group compared with telmi+HCTZ group in ITT (p=0.022) and mITT (p=0.015) populations after 4 weeks. At Week 8, a significant reduction in BP was seen compared to the baseline in both the treatment groups. There was no statistically significant difference between the two treatment groups in BP normalization. Diastolic BP responder rates were significantly better for triple pill group in PP population (p=0.046). CONCLUSIONS: The triple pill was found to be effective in achieving early normalization of BP in hypertensive patients who did not respond to monotherapies.


Assuntos
Anlodipino/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hidroclorotiazida/uso terapêutico , Telmisartan/uso terapêutico , Combinação de Medicamentos , Quimioterapia Combinada , Hipertensão Essencial , Humanos
9.
Phys Chem Chem Phys ; 19(16): 10629-10643, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28397906

RESUMO

This work reports the exploitation of nanocrystalline Ni0.5Zn0.5Fe2-xCexO4 ferrite for potential application by designing quasi-spherical shaped polythiophene (PTH) composites via in situ emulsion polymerization. The structural, electronic, dielectric, magnetic, and electromagnetic interference (EMI) shielding properties of PTH/Ni0.5Zn0.5Fe2-xCexO4 composites were investigated. Our results suggest that these properties could be optimized by modulating the concentration of x (composition) in the polymer matrix. Higher values of ε' and ε'' were obtained on composite formation, and could be due to the heterogeneity developed in the material. An enhancement in the value of saturation magnetization (123 emu g-1 for x = 0.04) and Curie temperature was obtained with Ce concentration, which is useful for high density recording purposes. A low value of saturation magnetization was obtained for the PTH/Ni0.5Zn0.5Fe2-xCexO4 composite (36 emu g-1 for x = 0.04). This could be attributed to the non-magnetic nature of the polymer. A total shielding effectiveness (SET = SEA + SER) up to 34 dB (≈99.9% attenuation) was recorded for PTH/Ni0.5Zn0.5Fe2-xCexO4 composites (x = 0.04) in a frequency range of 8.2-12.4 GHz (X-band), which surpasses the shielding criteria of SET > 30 dB for commercial purposes. Such a material with high SE identifies its potential for making electromagnetic shields. The effect of Ce substitution on the microstructure, dielectric, impedance and magnetic properties of PTH/Ni0.5Zn0.5Fe2-xCexO4 ferrite composites was also investigated. X-ray diffraction analysis confirmed cubic spinel phase formation, and the broad reflection peaks indicated the formation of smaller sized particles. The smaller energy band gap (2.53 eV) of the composite indicated that this material could be used for photocatalysis in the visible region. Dielectric and impedance measurements were carried out in a frequency range of 8.2-12.4 GHz. Dielectric properties were improved considerably by the substitution of Ce3+ ions in PTH/Ni0.5Zn0.5Fe2-xCexO4 composites. Impedance spectroscopy was used to study the effect of grain and grain boundaries on the electrical properties of PTH/Ni0.5Zn0.5Fe2-xCexO4 composites. Cole-Cole plots showed the formation of single semi-circles for all samples in the measured frequency range. This showed that the composite material was composed of good conducting grains and poorly conducting grain boundaries.

10.
ACS Appl Mater Interfaces ; 8(16): 10600-8, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27035889

RESUMO

Lightweight and easily foldable with high conductivity, multiwalled carbon nanotube (MWCNT)-based mesocarbon microbead (MCMB) composite paper is prepared using a simple, efficient, and cost-effective strategy. The developed lightweight and conductive composite paper have been reported for the first time as an efficient electromagnetic interference (EMI) shielding material in X-band frequency region having a low density of 0.26 g/cm(3). The investigation revealed that composite paper shows an excellent absorption dominated EMI shielding effectiveness (SE) of -31 to -56 dB at 0.15-0.6 mm thickness, respectively. Specific EMI-SE of as high as -215 dB cm(3)/g exceeds the best values of metal and other low-density carbon-based composites. Additionally, lightweight and easily foldable ability of this composite paper will help in providing stable EMI shielding values even after constant bending. Such intriguing performances open the framework to designing a lightweight and easily foldable composite paper as promising EMI shielding material, especially in next-generation devices and for defense industries.

11.
Acta Physiol (Oxf) ; 213(4): 846-59, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25683465

RESUMO

AIM: Various types of cholinergic receptors are expressed on intestinal epithelia. Their function is not completely understood. We hypothesize that cholinergic receptor activation on epithelium may serve a protective function in cytokine-induced barrier dysfunction. METHODS: The effect of cholinergic receptor activation on cellular barrier function in epithelial cells was assessed by measuring electrical impedance, and by determining para-cellular transport in transwell experiments. Cell lysates treated with cytokine and/or cholinergic agonists were analysed for cyto- and chemokine production, and tight junction (TJ) protein rearrangement was assessed. Primary colonic epithelial cells were isolated from surgically resected colon tissue of patients with inflammatory bowel disease. RESULTS: IL-1ß induced production of chemokines (CXCL-1, CXCL-10, IL-8, CCL-7) and led to a rearrangement of TJ proteins (occludin and ZO-1). This response was inhibited by pre-treatment with muscarinic, rather than nicotinic, acetylcholine receptor agonists. Treatment with IL-1ß enhanced paracellular permeability (4kD dextran) and reduced impedance across the monolayer, which was counteracted by pre-incubation with acetylcholine, or muscarinic receptor agonist bethanechol. The protective effect of acetylcholine was antagonized by atropine, underscoring muscarinic receptor involvement. IL-1ß induced transcription of myosin light chain kinase and phosphorylation of myosin light chain, and this cytokine-induced phosphorylation of MLC was inhibited by muscarinic receptor agonists. Furthermore, in epithelial cells from resection material of patients with Crohn's disease and ulcerative colitis, high expression of CXCL-8 was associated with a reduced choline acetyl transferase expression, suggesting an aberrant epithelial production of ACh in inflammatory context. CONCLUSION: Acetylcholine acts on muscarinic receptors on epithelial cells to maintain epithelial barrier function under inflammatory conditions.


Assuntos
Citocinas/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Receptores Colinérgicos/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Citocinas/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Interleucina-1beta/farmacologia , Camundongos , Ocludina/genética , Ocludina/metabolismo , Receptores Colinérgicos/genética , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
12.
Phys Chem Chem Phys ; 17(3): 1610-8, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25437769

RESUMO

There is an increased interest in the development of high performance microwave shielding materials against electromagnetic pollution in recent years. Barium ferrite decorated reduced graphene oxide (BaFe12O19@RGO) nanocomposite was synthesized by a high energy ball milling technique and its electromagnetic properties were investigated in the frequency range of 12.4-18 GHz (Ku band). The results showed that barium ferrite (BaFe12O19) nanoparticles with an average particle size of 20-30 nm were well distributed and firmly anchored onto the surface of the reduced graphene oxide sheets. The obtained nanocomposite exhibited a saturation magnetization of 18.1 emu g(-1) at room temperature. The presence of BaFe12O19 nanoparticles in the nanocomposite enhances the space charge polarization, natural resonance, multiple scattering and the effective anisotropy energy leading to a high electromagnetic interference shielding effectiveness of 32 dB (∼99.9% attenuation) at a critical thickness of 3 mm. The results suggested that the as-prepared BaFe12O19@RGO nanocomposite showed great potential as an effective candidate for a new type of microwave absorbing material.

13.
Nanoscale ; 5(6): 2411-20, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23400248

RESUMO

The development of high-performance shielding materials against electromagnetic pollution requires mobile charge carriers and magnetic dipoles. Herein, we meet the challenge by building a three-dimensional (3D) nanostructure consisting of chemically modified graphene/Fe3O4(GF) incorporated polyaniline. Intercalated GF was synthesized by the in situ generation of Fe3O4 nanoparticles in a graphene oxide suspension followed by hydrazine reduction, and further in situ polymerization with aniline to form a polyaniline composite. Spectroscopic analysis demonstrates that the presence of GF hybrid structures facilitates strong polarization due to the formation of a solid-state charge-transfer complex between graphene and polyaniline. This provides proper impedance matching and higher dipole interaction, which leads to the high microwave absorption properties. The higher dielectric loss (ε'' = 30) and magnetic loss (µ'' = 0.2) contribute to the microwave absorption value of 26 dB (>99.7% attenuation), which was found to depend on the concentration of GF in the polyaniline matrix. Moreover, the interactions between Fe3O4, graphene and polyaniline are responsible for superior material characteristics, such as excellent environmental (chemical and thermal) degradation stability and good electric conductivity (as high as 260 S m(-1)).

15.
Neurogastroenterol Motil ; 24(2): 172-84, e91, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22122661

RESUMO

BACKGROUND: Abdominal surgery involving bowel manipulation commonly results in inflammation of the bowel wall, which leads to impaired intestinal motility and postoperative ileus (POI). Mast cells have shown to play a key role in the pathogenesis of POI in mouse models and human studies. We studied whether mast cells contribute to the pathogenesis of POI by eliciting intestinal barrier dysfunction. METHODS: C57BL/6 mice, and two mast cell-deficient mutant mice Kit(W/W-v) , and Kit(W-sh/W-sh) underwent laparotomy (L) or manipulation of the small bowel (IM). Postoperative inflammatory infiltrates and cytokine production were assessed. Epithelial barrier function was determined in Ussing chambers, by measuring transport of luminal particles to the vena mesenterica, and by assessing bacterial translocation. KEY RESULTS: In WT mice, IM resulted in pro-inflammatory cytokine and chemokine production, and neutrophil extravasation to the manipulated bowel wall. This response to IM was reduced in mast cell-deficient mice. IM caused epithelial barrier dysfunction in WT mice, but not in the two mast cell-deficient strains. IM resulted in a decrease in mean arterial pressure in both WT and mast cell-deficient mice, indicating that impaired barrier function was not explained by tissue hypoperfusion, but involved mast cell mediators. CONCLUSIONS & INFERENCES: Mast cell activation during abdominal surgery causes epithelial barrier dysfunction and inflammation of the muscularis externa of the bowel. The impairment of the epithelial barrier likely contributes to the pathogenesis of POI. Our data further underscore that mast cells are bona fide cellular targets to ameliorate POI.


Assuntos
Translocação Bacteriana , Íleus/patologia , Inflamação/patologia , Intestino Delgado/patologia , Laparotomia/efeitos adversos , Mastócitos/patologia , Animais , Modelos Animais de Doenças , Feminino , Motilidade Gastrointestinal , Íleus/etiologia , Íleus/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/metabolismo , Intestino Delgado/cirurgia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade , Células-Tronco
16.
Nanotechnology ; 22(46): 465701, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-22024967

RESUMO

This paper deals with the preparation of graphene oxide-ferrofluid-cement nanocomposites to evaluate the electromagnetic interference (EMI) shielding effectiveness (SE) in the 8.2-12.4 GHz frequency range. It has been observed that incorporation of graphene oxide (30 wt%) along with an appropriate amount of ferrofluid in the cement matrix leads to a shielding effectiveness of 46 dB (>99% attenuation).The presence of graphene oxide and ferrofluid in the cement leads to strong polarizations and magnetic losses that consequently result in higher shielding effectiveness compared to pristine cement. The resulting nanocomposites have shown Shore hardness of 54 and dc conductivity of 10.40 S cm( - 1). SEM reveals the homogeneous dispersion of graphene oxide and ferrofluid in the cement matrix.

17.
Genet Mol Res ; 10(3): 2049-56, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21968621

RESUMO

Velvet bean (Mucuna pruriens) seeds contain the catecholic amino acid L-DoPA (L-3,4-dihydroxyphenylalanine), which is a neurotransmitter precursor and used for the treatment of Parkinson's disease and mental disorders. The great demand for L-DoPA is largely met by the pharmaceutical industry through extraction of the compound from wild populations of this plant; commercial exploitation of this compound is hampered because of its limited availability. The trichomes present on the pods can cause severe itching, blisters and dermatitis, discouraging cultivation. We screened genetic stocks of velvet bean for the trichome-less trait, along with high seed yield and L-DoPA content. The highest yielding trichome-less elite strain was selected and indentified on the basis of a PCR-based DNA fingerprinting method (RAPD), using deca-nucleotide primers. A genetic similarity index matrix was obtained through multivariant analysis using Nei and Li's coefficient. The similarity coefficients were used to generate a tree for cluster analysis using the UPGMA method. Analysis of amplification spectra of 408 bands obtained with 56 primers allowed us to distinguish a trichome-less elite strain of M. pruriens.


Assuntos
Levodopa/biossíntese , Mucuna/genética , Sementes/genética , Testes Genéticos , Genótipo , Mucuna/química , Mucuna/metabolismo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Sementes/química , Sementes/enzimologia
18.
Philos Trans A Math Phys Eng Sci ; 369(1953): 4064-77, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21930565

RESUMO

It is now recognized that the International System of Units (SI units) will be redefined in terms of fundamental constants, even if the date when this will occur is still under debate. Actually, the best estimate of fundamental constant values is given by a least-squares adjustment, carried out under the auspices of the Committee on Data for Science and Technology (CODATA) Task Group on Fundamental Constants. This adjustment provides a significant measure of the correctness and overall consistency of the basic theories and experimental methods of physics using the values of the constants obtained from widely differing experiments. The physical theories that underlie this adjustment are assumed to be valid, such as quantum electrodynamics (QED). Testing QED, one of the most precise theories is the aim of many accurate experiments. The calculations and the corresponding experiments can be carried out either on a boundless system, such as the electron magnetic moment anomaly, or on a bound system, such as atomic hydrogen. The value of fundamental constants can be deduced from the comparison of theory and experiment. For example, using QED calculations, the value of the fine structure constant given by the CODATA is mainly inferred from the measurement of the electron magnetic moment anomaly carried out by Gabrielse's group. (Hanneke et al. 2008 Phys. Rev. Lett. 100, 120801) The value of the Rydberg constant is known from two-photon spectroscopy of hydrogen combined with accurate theoretical quantities. The Rydberg constant, determined by the comparison of theory and experiment using atomic hydrogen, is known with a relative uncertainty of 6.6×10(-12). It is one of the most accurate fundamental constants to date. A careful analysis shows that knowledge of the electrical size of the proton is nowadays a limitation in this comparison. The aim of muonic hydrogen spectroscopy was to obtain an accurate value of the proton charge radius. However, the value deduced from this experiment contradicts other less accurate determinations. This problem is known as the proton radius puzzle. This new determination of the proton radius may affect the value of the Rydberg constant . This constant is related to many fundamental constants; in particular, links the two possible ways proposed for the redefinition of the kilogram, the Avogadro constant N(A) and the Planck constant h. However, the current relative uncertainty on the experimental determinations of N(A) or h is three orders of magnitude larger than the 'possible' shift of the Rydberg constant, which may be shown by the new value of the size of the proton radius determined from muonic hydrogen. The proton radius puzzle will not interfere in the redefinition of the kilogram. After a short introduction to the properties of the proton, we will describe the muonic hydrogen experiment. There is intense theoretical activity as a result of our observation. A brief summary of possible theoretical explanations at the date of writing of the paper will be given. The contribution of the proton radius puzzle to the redefinition of SI-based units will then be examined.

19.
Indian J Pharm Sci ; 71(5): 585-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20502586

RESUMO

A rapid, sensitive, simple, and cost-effective spectrofluorimetric method was developed for the estimation of rivastigmine in bulk and pharmaceutical formulations. The relative fluorescence intensity of rivastigmine was measured in triple distilled water at an excitation wavelength of 220 nm and an emission wavelength of 289 nm. Linearity range was found to be 100 to 4000 ng/ml. The method was validated for various parameters as per the ICH guidelines and USP requirements. The detection and quantitation limits were found to be 20.5 and 62.1 ng/ml, respectively. The results demonstrate that the procedure is accurate, precise, and reproducible, while being simple and rapid too. The results were found to be in good agreement with the label claims.

20.
Phys Rev Lett ; 100(9): 091602, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18352695

RESUMO

The spin precession frequency of muons stored in the (g-2) storage ring has been analyzed for evidence of Lorentz and CPT violation. Two Lorentz and CPT violation signatures were searched for a nonzero delta omega a(=omega a mu+ - omega a mu-) and a sidereal variation of omega a mu+/-). No significant effect is found, and the following limits on the standard-model extension parameters are obtained: bZ = -(1.0+/-1.1) x 10(-23) GeV; (m mu dZ0 + HXY)=(1.8+/-6.0) x 10(-23) GeV; and the 95% confidence level limits b perpendicular mu+ <1.4 x 10(-24) GeV and b perpendicular mu- <2.6 x 10(-24) GeV.

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