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1.
Glia ; 71(10): 2323-2342, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37269227

RESUMO

Ceruloplasmin (Cp) is a ferroxidase enzyme that is essential for cell iron efflux. The absence of this protein in humans and rodents produces progressive neurodegeneration with brain iron accumulation. Astrocytes express high levels of Cp and iron efflux from these cells has been shown to be central for oligodendrocyte maturation and myelination. To explore the role of astrocytic Cp in brain development and aging we generated a specific conditional KO mouse for Cp in astrocytes (Cp cKO). Deletion of Cp in astrocytes during the first postnatal week induced hypomyelination and a significant delay in oligodendrocyte maturation. This abnormal myelin synthesis was exacerbated throughout the first two postnatal months and accompanied by a reduction in oligodendrocyte iron content, as well as an increase in brain oxidative stress. In contrast to young animals, deletion of astrocytic Cp at 8 months of age engendered iron accumulation in several brain areas and neurodegeneration in cortical regions. Aged Cp cKO mice also showed myelin loss and oxidative stress in oligodendrocytes and neurons, and at 18 months of age, developed abnormal behavioral profiles, including deficits in locomotion and short-term memory. In summary, our results demonstrate that iron efflux-mediated by astrocytic Cp-is essential for both early oligodendrocyte maturation and myelin integrity in the mature brain. Additionally, our data suggest that astrocytic Cp activity is central to prevent iron accumulation and iron-induced oxidative stress in the aging CNS.


Assuntos
Astrócitos , Ceruloplasmina , Humanos , Camundongos , Animais , Idoso , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Astrócitos/metabolismo , Bainha de Mielina/metabolismo , Camundongos Knockout , Encéfalo/metabolismo , Ferro/metabolismo , Oligodendroglia/metabolismo
2.
Molecules ; 28(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985459

RESUMO

An innovative form of 2D/0D g-C3N4/CeO2 nanostructure was synthesized using a simple precursor decomposition process. The 2D g-C3N4 directs the growth of 0D CeO2 quantum dots, while also promoting good dispersion of CeO2QDs. This 2D/0D nanostructure shows a capacitance of 202.5 F/g and notable rate capability and stability, outperforming the g-C3N4 electrode, reflecting the state-of-the-art g-C3N4 binary electrodes. The binary combination of materials also enables an asymmetric device (g-C3N4/CeO2QDs//AC) to deliver the highest energy density (9.25 Wh/kg) and power density (900 W/kg). The superior rate capacity and stability endorsed the quantum structural merits of CeO2QDs and layered g-C3N4, which offer more accessible sites for ion transport. These results suggest that the g-C3N4/CeO2QDs nanostructure is a promising electrode material for energy storage devices.

3.
BMC Public Health ; 21(1): 618, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785012

RESUMO

BACKGROUND: Despite current preventative strategies, road traffic collisions (RTCs) and resultant neurotrauma remain a major problem in India. This study seeks to explore local perspectives in the context within which RTCs take place and identify potential suggestions for improving the current status. METHODS: Ten semi-structured interviews were carried out with purposively selected key informants from the city of Visakhapatnam, Andhra Pradesh. Participants were from one of the following categories: commissioning stakeholders; service providers; community or local patient group/advocacy group representatives. Transcripts from these interviews were analysed qualitatively using the Framework Method. RESULTS: Participants felt RTCs are a serious problem in India and a leading cause of neurotrauma. Major risk factors identified related to user behaviour such as speeding and not using personal safety equipment, and the user state, namely drink driving and underage driving. Other reported risk factors included poor infrastructure, moving obstacles on the road such as other vehicles, pedestrians and animals, overloaded vehicles and substandard safety equipment. Participants discussed how RTCs affect not only the health of the casualty, but are also a burden to the healthcare system, families, and the national economy. Although there are ongoing preventative strategies being carried out by both the government and the community, challenges to successful prevention emerged from the interviews which included resource deficiencies, inconsistent implementation, lack of appropriate action, poor governance, lack of knowledge and the mindset of the community and entities involved in prevention. Recommendations were given on how prevention of RTCs and neurotrauma might be improved, addressing the areas of education and awareness, research, the pre-hospital and trauma systems, enforcement and legislation, and road engineering, in addition to building collaborations and changing mindsets. CONCLUSIONS: RTCs remain a major problem in India and a significant cause of neurotrauma. Addressing the identified gaps and shortfalls in current approaches and reinforcing collective responsibility towards road safety would be the way forward in improving prevention and reducing the burden.


Assuntos
Condução de Veículo , Pedestres , Ferimentos e Lesões , Acidentes de Trânsito/prevenção & controle , Cidades , Humanos , Índia/epidemiologia , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controle
4.
J Am Coll Nutr ; 38(3): 227-234, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30485164

RESUMO

OBJECTIVE: The purpose of the study was to assess impact of vitamin D supplements on the disease progression and overall health of osteoarthritis (OA) patients. METHODOLOGY: A cohort study was carried out for 8 months (August 2017-March 2018) in the Orthopedics Department of Kasturba Hospital, Manipal, India, a tertiary care hospital. One hundred and forty-two patients who were diagnosed with OA (grades 1-3) with low serum 25(OH)D levels (severely deficient, deficient, or insufficient) were selected for the study. These patients were categorized into two cohorts: a control cohort (CC) and a study cohort (SC). CC members were patients (n = 71) who had not received vitamin D supplements, and SC members were patients (n = 71) who had received vitamin D supplements. Severity grading of OA, pain score, and health assessment were performed using the Kellgren-Laurence grading score, visual analogue scale (VAS), and WOMAC, respectively, at baseline and after 3 months of follow-up. RESULTS: Subjects in the both CC and SC reported no statistically significant difference (similar in both group) in severity grade (p = 0.303), pain score (p = 0.099), parathyroid hormone (PTH) (p = 0.083), and health status (p = 0.76) at baseline. After 3 months of follow-up (post vitamin D supplementation), OA patients have shown statistically significant difference in severity grades, serum 25(OH)D status, PTH level (p < 0.001), and overall health status (p = 0.001) in the SC with respect to baseline. Likewise, percentage distribution of positive changes was significantly higher in severity grade, pain score, serum 25(OH)D level, overall health status (p < 0.001), and PTH (p = 0.040) of SC as compared to CC at follow-up. CONCLUSION: Vitamin D supplements have significantly improved serum 25(OH)D levels, PTH, severity grade, and pain score of OA patients. Most importantly, vitamin D supplements have shown improvement in the overall health of OA patients, emphasizing the place of vitamin D supplements in the management of OA. Clinical Trial Registry-India (CTRI) registration no: CTRI/2017/12/011031.


Assuntos
Suplementos Nutricionais , Osteoartrite/tratamento farmacológico , Centros de Atenção Terciária , Vitamina D/uso terapêutico , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitamina D/administração & dosagem , Vitamina D/sangue
5.
Biol Lett ; 15(7): 20190289, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31311485

RESUMO

Fish inhabiting human-dominated ecosystems are prone to altered sensory environments in which they must live and function. Increased turbidity is one such change that they must deal with. We tested whether an increase in water turbidity and the presence of visual landmarks (coloured stones) affect the foraging efficiency of wild zebrafish. We also tested the influence of extended exposure to differing turbidity levels on the subsequent foraging efficiency of acclimatized individuals. Feeding latency (time taken to find food) increased significantly with increase in turbidity levels from a minimum of 4 s to ca 300 s. However, extended exposure of fish to varying levels of turbidity decreased feeding latencies in acclimatized conditions, indicating that acclimatization to the immediate visual environment plays an important role in determining foraging success. Most significantly, we found that feeding latencies in turbid conditions decreased significantly if visual landmarks were present. This demonstrates that zebrafish use visual landmark cues to navigate to foraging sites when visibility is impaired. This study has important implications on the role of behavioural plasticity and spatial learning in animals that allow them to cope with altered sensory environments such as episodes of enhanced turbidity that could be natural or anthropogenic.


Assuntos
Ecossistema , Peixe-Zebra , Aclimatação , Animais , Sinais (Psicologia)
6.
Nanotechnology ; 29(24): 245202, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29578458

RESUMO

Black phosphorus, a two-dimensional material, with high carrier mobility, tunable direct bandgap and anisotropic electronic properties has attracted enormous research interest towards potential application in electronic, optoelectronic and optomechanical devices. The bandgap of BP is thickness dependent, ranging from 0.3 eV for bulk to 1.3 eV for monolayer, while lacking in the visible region, a widely used optical regime for practical optoelectronic applications. In this work, photoluminescence (PL) centered at 605 nm is observed from the thermally annealed BP with thickness ≤20 nm. This higher energy PL is most likely the consequence of the formation of higher bandgap phosphorene oxides and suboxides on the surface BP layers as a result of the enhanced rate of oxidation. Moreover, the polarization-resolved PL measurements show that the emitted light is anisotropic when the excitation polarization is along the armchair direction. However, if excited along zigzag direction, the PL is nearly isotropic. Our findings suggest that the thermal annealing of BP can be used as a convenient route to fill the visible gap of the BP-based optoelectronic and optomechanical devices.

7.
Phys Chem Chem Phys ; 19(2): 1536-1542, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27990519

RESUMO

Surface protection using an appropriate ligand is essential for controlling the size, stability and luminescence properties of the quantum dots (QDs). Though 3-mercaptopropanoic acid (3-MPA) is regarded as the most suitable protecting ligand among the mercapto acids for water soluble CdTe QDs, one receives a different picture from recent studies, which report a much higher luminescence efficiency of 3-mercaptobutyric acid (3-MBA) capped QDs compared with those capped by 3-MPA and attribute the observation to the influence of the side methyl group of mercapto acids. Herein we report the luminescence properties and carrier trapping dynamics of four different, but structurally related mercapto acid capped CdTe QDs prepared using a different method. The results show that these QDs are much more fluorescent than those prepared directly in an aqueous environment and surprisingly, no enhanced luminescence for the QDs capped by mercapto acids containing a side methyl group is observed. Ultrafast pump-probe measurements confirm these results in addition to providing insight into the carrier trapping dynamics of these systems. It is shown that our findings, which appear to be in conflict with the recent literature, can be rationalized and the exact role of the side methyl group of the mercapto acids can be understood by careful analysis of the results taking into consideration the difference in the methods of preparation of the QDs in the two cases.

8.
Indian J Microbiol ; 57(2): 250-252, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28611504

RESUMO

Arcobacter is an emerging foodborne pathogen having zoonotic significance. Enterobacterial repetitive intergenic consensus (ERIC) PCR and repetitive sequence-based PCR (rep-PCR) analysis of a total of 41 Arcobacter isolates revealed a greater degree of genetic diversity. ERIC-PCR genotyping distinguished 14, 13 and 12 genotypes among 16, 13 and 12 isolates of A. butzleri, A. cryaerophilus and A. skirrowii, respectively. Rep-PCR genotyping distinguished 15, 12 and 11 genotypes among 16, 13 and 12 isolates of A. butzleri, A. cryaerophilus and A. skirrowii, respectively. The discriminatory power for ERIC and rep-PCR was found to be 0.997 and 0.996, respectively. Close clustering between isolates of animal and human origin are indicative of probable zoonotic significance.

9.
Transfus Med ; 26(6): 422-431, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27511318

RESUMO

OBJECTIVES: To implement a patient blood management (PBM) programme in platelet transfusion. AIMS: To improve the appropriate use of blood components, reduce wastage and generate savings. BACKGROUND: PBM is a multidisciplinary, evidence-based approach to optimising the care of patients who need blood transfusion and to use blood products appropriately. Strategies for PBM ensure that patients receive the best possible treatment with the transfusion of components when indicated, at the same time avoiding or reducing unnecessary transfusions. Typically, PBM initiatives have addressed the use of red cells. PBM initiatives in platelets (PBM-P) are an important aspect of Transfusion Medicine. METHODS: We present data from an initiative for PBM-platelets (PBM-P) comprising a service improvement programme through the role of a 'platelet co-ordinator' (PBM-Pc) to optimise the use of platelets in a large complex tertiary care hospital in a National Health Service (NHS) setting. RESULTS: Analysis at 18 months of the role showed sustained improvement in compliance with quality standards defined by British Committee for Standards in Haematology (BCSH) guidelines and significant financial savings due to improved use and reduced wastage. The appropriate use of platelets increased by 17, 23 and 18% in the prophylactic, pre-procedure and peri-procedure categories, respectively. Importantly, despite concurrent increases of patient activity, platelet issues and cost reduced by 21% over the period of analysis. CONCLUSIONS: Our model has been efficacious in delivering the effective stewardship of platelets and can be successfully implemented in NHS.


Assuntos
Transfusão de Plaquetas/normas , Gerenciamento da Prática Profissional , Feminino , Humanos , Masculino
10.
ScientificWorldJournal ; 2016: 1875865, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27403451

RESUMO

This study is to probe the pattern of antibiotic resistance against aminoglycosides and its mechanism in E. coli obtained from patients from Chennai, India. Isolation and identification of pathogens were done on MacConkey agar. Antimicrobial sensitivity testing was done by disc diffusion test. The identification of genes encoding aminoglycoside modifying enzymes was done by Polymerase Chain Reaction (PCR). Out of 98 isolates, 71 (72.45%) isolates were identified as E. coli and the remaining 27 (27.55%) as other bacteria. Disc diffusion method results showed a resistance level of 72.15% for streptomycin, 73.4% for gentamicin, 63.26% for neomycin, 57.14% for tobramycin, 47.9% for netilmicin, and 8.16% for amikacin in E. coli. PCR screening showed the presence of four genes, namely, rrs, aacC2, aacA-aphD, and aphA3, in their plasmid DNA. The results point towards the novel mechanism of drug resistance in E. coli from UTI patients in India as they confirm the presence of genes encoding enzymes that cause resistance to aminoglycoside drugs. This could be an alarm for drug prescription to UTI patients.


Assuntos
Aminoglicosídeos/genética , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Infecções Urinárias/microbiologia , Antibacterianos/farmacologia , Escherichia coli/enzimologia , Humanos , Índia , Testes de Sensibilidade Microbiana
12.
Saudi Pharm J ; 23(1): 1-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25685036

RESUMO

BACKGROUND: Drug related admissions have significantly increased over the past few decades. According to various studies on drug related hospital admissions, it was estimated that around 5-10% of hospital admissions were due to drug related problems (DRP), in which 50% of them are avoidable. OBJECTIVE: The objective of the study was to derive results from various studies conducted on drug related hospital admissions and have an overall view about the incidence, frequency, cost of treatment, major causative drugs, problems for drug related hospital admissions, and preventable drug related admissions and summarize the factors responsible for the occurrence of DRP. METHOD: Relevant literatures related to 'drug related hospital admissions' were obtained from PubMed database. Articles that were published from October 2007 to September 2012 were collected. All the studies being shown in the search results were considered for the study irrespective of the specialty department. RESULTS: A total of 366 articles were found based on the keyword 'drug related hospital admission', 'drug related problem admission', and 'adverse drug event admissions' search. Out of which 49 articles were identified to be showing relevance to the study. Non-English, abstract-only articles, and out-patient adverse drug reaction (ADR) studies were filtered from 49 articles. Finally 15 articles were taken up for the study. Systemic analysis was made on these articles and the results were summarized. CONCLUSION: Most of DRP studies were retrospective, multicenter studies conducted in general populations in Europe. The main objective of the studies was to estimate DRP frequency, incidence, risk factors and trends of DRP hospital admissions. Anti-neoplastic agents, CVS drugs and CNS drugs were related to most of the drug related problems. These studies concluded polypharmacy and older age were the major risk factors for developing drug related problems. It was found that the cost for the management of DRP was directly proportional to severity.

13.
J Phys Chem A ; 118(45): 10487-96, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24958234

RESUMO

The mechanism of intramolecular cycloadditions of azaxylylenes photogenerated via excited-state intramolecular proton transfer (ESIPT) in aromatic o-amido ketones and aldehydes bearing unsaturated functionalities was studied experimentally and computationally. In time-correlated single-photon counting experiments, no relation was found between lifetimes of singlet species and the nature of the amide pendant, either unsaturated furanpropanamide, capable of photocyclization, or the acetamide control. Steady-state emission for amido-tetralone derivatives showed comparable dual emission bands, but bromo substitution decreased the intensity of the ESIPT band. The most reactive derivatives of amidobenzaldehydes were virtually lacking the ESIPT band. The quantum yield of cycloaddition is decreased in the presence of triplet quenchers, O2 or trans-piperylene, and improved with heavy atom substitution in the aromatic ring, providing further evidence for the initial mechanistic hypothesis in which the fast singlet-state ESIPT is accompanied by the ISC in the tautomer (azaxylylene), which undergoes stepwise addition to the tethered unsaturated pendants.

14.
J Ayurveda Integr Med ; 15(1): 100860, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38320447

RESUMO

BACKGROUND: While several drugs are in the pipeline for treatment of various grades of COVID-19 disease, none of them have shown promise until now. Medicinal plants are crucial in developing and developed countries for their primary and basic health needs owing to better tolerability, superior compatibility with human body and having lesser side effects. OBJECTIVE: To test adjuvant effect of AEV01, a patented herbal extract of kutki (Picrorhiza kurroa), in mild COVID19 in elderly patients at risk of complications and aging immunity. METHODS: A prospective, phase 3, randomized, multicentric, placebo controlled double blinded parallel group interventional trial was conducted in elderly patients aged above 50 years diagnosed as COVID-19 with mild symptoms. 70 patients were randomized into two groups to receive AEV01 capsule (100 mg) and placebo respectively thrice daily for 30 days along with standard care of treatment as per national (WHO/ICMR) guidelines in both the groups. Clinical improvement timelines and corresponding scores using 8-point ordinal scale and NEWS were assessed for efficacy and safety of AEV01 in COVID-19 patients. RESULTS: AEV01 group showed a significant improvement (p = 0.0001) in the normalization of the SpO2 rate and relief from cough. There was also significant difference in time to recovery, with patients in the AEV01 drug treated group recovering in 4.5 days as compared to Placebo in 9.1 days. ESR, LDH, serum ferritin, Neutrophil-Lymphocyte ratio (NLR), TNF- alpha, IL-6 and CD4 cell counts, which are considered as prognostic markers in COVID-19 infected patients, showed a significant improvement in patients treated with AEV01. The AEV01 drug treated group showed significant clinical improvement in the 8-point ordinal scale severity rating and National Early Warning Score (NEW) Score from day 3 onwards which continued up to end of study. CONCLUSION: AEV01 has shown a significant improvement in clinical and laboratory parameters. There was also reduction in the progression of the COVID-19 disease in unvaccinated elderly patients from mild to moderate when treated at an earlier stage.

15.
Sci Total Environ ; 877: 162869, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36933723

RESUMO

The over-exploitation and insufficient replenishment of groundwater (GW) have resulted in a pressing need to conserve freshwater and reuse of treated wastewater. To address this issue, the Government of Karnataka launched a large-scale recycling (440 million liters/day) scheme to indirectly recharge GW using secondary treated municipal wastewater (STW) in drought-prone areas of Kolar district in southern India. This recycling employs soil aquifer treatment (SAT) technology, which involves filling surface run-off tanks with STW that intentionally infiltrate and recharge aquifers. This study quantifies the impact of STW recycling on GW recharge rates, levels, and quality in the crystalline aquifers of peninsular India. The study area is characterized by hard rock aquifers with fractured gneiss, granites, schists, and highly fractured weathered rocks. The agricultural impacts of the improved GW table are also quantified by comparing areas receiving STW to those not receiving it, and changes before and after STW recycling were measured. The AMBHAS_1D model was used to estimate the recharge rates and showed a tenfold increase in daily recharge rates, resulting in a significant increase in the GW levels. The results indicate that the surface water in the rejuvenated tanks meets the country's stringent water discharge standards for STW. The GW levels of the studied boreholes increased by 58-73 %, and the GW quality improved significantly, turning hard water into soft water. Land use land cover studies confirmed an increase in the number of water bodies, trees, and cultivated land. The availability of GW significantly improved agricultural productivity (11-42 %), milk productivity (33 %), and fish productivity (341 %). The study's outcomes are expected to serve as a role model for the rest of Indian metro cities and demonstrate the potential of reusing STW to achieve a circular economy and a water-resilient system.

16.
Opt Express ; 20(9): 9624-39, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22535054

RESUMO

Thin films of Bi(x)Ce(3-x)Fe(5)O(12) with x = 0.7 and 0.8 compositions were prepared by using pulsed laser deposition. We investigated the effects of processing parameters used to fabricate these films by measuring various physical properties such as X-ray diffraction, transmittance, magnetization and Faraday rotation. In this study, we propose a phase diagram which provides a suitable window for the deposition of Bi(x)Ce(3-x)Fe(5)O(12) epitaxial films. We have also observed a giant Faraday rotation of 1-1.10 degree/µm in our optimized films. The measured Faraday rotation value is 1.6 and 50 times larger than that of CeYIG and YIG respectively. A theoretical model has been proposed for Faraday rotation based on density matrix method and an excellent agreement between experiment and theory is found.


Assuntos
Bismuto/química , Cério/química , Membranas Artificiais , Adsorção , Campos Magnéticos , Teste de Materiais , Rotação
17.
Genet Couns ; 23(4): 473-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23431746

RESUMO

Chromosome analysis of cultured lymphocytes from an 18 year old mentally retarded boy with minor dysmorphic features revealed a de novo inverted insertion translocation involving chromosomes 1 and 2. The chromosome complement was interpreted as 46,XY, inv ins(1;2)(q44;p12pter). Parents were phenotypically normal with no chromosomal anomalies.


Assuntos
Transtornos Cromossômicos/genética , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 2/genética , Deficiência Intelectual/genética , Translocação Genética/genética , Adolescente , Transtornos Cromossômicos/diagnóstico , Inversão Cromossômica/genética , Predisposição Genética para Doença/genética , Humanos , Deficiência Intelectual/diagnóstico , Masculino , Síndrome
18.
Saudi Pharm J ; 20(1): 1-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23960771

RESUMO

Migraine is one of the common causes of severe and recurring headache. It may be difficult to manage in primary care settings, where it is under diagnosed and medically treated. Migraine can occur in children as well as in adults and it is three times more common in women than in men. Migraine in children is different from adults in various ways. Migraine management depends on the various factors like duration and severity of pain, associated symptoms, degree of disability, and initial response to treatment. The therapy of children and adolescents with migraines includes treatment modalities for acute attacks, prophylactic medications when the attacks are frequent, and biobehavioural modes of treatment to aid long-term management of the disorder. The long lasting outcome of childhood headaches and progression into adult headaches remains largely unknown. However, it has been suggested that adult migraine may represent a progressive disorder. In children, the progressive nature is uncertain and further investigations into longitudinal outcome and phenotypic changes in childhood headaches have yet to be recognized. Even though paediatric and adult migraines seem to be slightly different from one another, but not enough to categorize either as sole.

19.
J Phys Chem A ; 115(33): 9217-25, 2011 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-21812494

RESUMO

Photophysical properties of a natural plant alkaloid, ellipticine (5,11-dimethyl-6H-pyrido[4,3-b]carbazole), which comprises both proton donating and accepting sites, have been studied in different solvents using steady state and time-resolved fluorescence techniques primarily to understand the origin of dual fluorescence that this molecule exhibits in some specific alcoholic solvents. Ground and excited state calculations based on density functional theory have also been carried out to help interpretation of the experimental data. It is shown that the long-wavelength emission of the molecule is dependent on the hydrogen bond donating ability of the solvent, and in methanol, this emission band arises solely from an excited state reaction. However, in ethylene glycol, both ground and excited state reactions contribute to the long wavelength emission. The time-resolved fluorescence data of the system in methanol and ethylene glycol indicates the presence of two different hydrogen bonded species of ellipticine of which only one participates in the excited state reaction. The rate constant of the excited state reaction in these solvents is estimated to be around 4.2-8.0 × 10(8) s(-1). It appears that the present results are better understood in terms of solvent-mediated excited state intramolecular proton transfer reaction from the pyrrole nitrogen to the pyridine nitrogen leading to the formation of the tautomeric form of the molecule rather than excited state proton transfer from the solvents leading to the formation of the protonated form of ellipticine.


Assuntos
Antineoplásicos/química , Elipticinas/química , Solventes/química , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Elipticinas/farmacologia , Fluorescência , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Nitrogênio/química , Prótons , Piridinas/química , Solubilidade , Espectrometria de Fluorescência
20.
Saudi Pharm J ; 19(4): 273-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23960769

RESUMO

BACKGROUND AND OBJECTIVES: Accidental and intentional poisonings or drug overdoses constitute a significant source of aggregate morbidity, mortality, and health care expenditure. Studies evaluating drug related hospitalization have estimated that approximately 5-10% of all hospital admissions are drug related. The present study was carried out to investigate type, nature and incidence of drug related admissions in our hospital settings. METHOD: A hospital based retrospective study was conducted in 575 cases of drug related admissions. The case records of patients admitted in various clinical departments of Amrita Institute of Medical Sciences (AIMS) Hospital during last 8 years (January 2002-December 2009) were collected and analyzed. RESULTS: During the retrospective study, the total number of drug related cases reported were 575. Out of these, 35.5% cases were induced by central nervous system (CNS) drugs, 19.8% were by cardiovascular system (CVS) drugs, 12.3% were by NSAIDs, 11.3% were by antibiotics and 9.9% were by anticoagulants, 11.3% by other drugs which includes hormones, cytotoxic drugs, hypolipidemics, etc. Four hundred and forty cases were admitted to emergency department. Common drug related problems resulting in hospital visits were due to intentional, accidental and overdose. The incidence of drug related hospital admissions was found to be 0.20%. CONCLUSION: The most of the accidental and suicidal cases were reported are by CNS drugs. Psychiatric patients intentionally taking medicines as suicidal attempt and as a part of their illness. As drug related problems are so significant, increased awareness and enhanced collaborative efforts among patients, physicians, pharmacists and caregivers within community and hospital have the potential to minimize the impact of this problem.

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