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1.
Environ Monit Assess ; 193(6): 324, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33948733

RESUMO

Aerosol optical depth (AOD) and Ångström exponent (AE) are observed to be important parameters in understanding the status of ambient aerosol concentration over a particular location and depend not only upon the local but also on the large-scale dynamics of the atmosphere. The present article analyses the AOD and AE parameters retrieved with Moderate Resolution Imaging Spectrometer (MODIS) and Multi-angle Imaging Spectro-Radiometer (MISR) instruments onboard satellites, for the upper (Chamoli) and foothill (Dehradun) regions of Garhwal Himalaya in Uttarakhand, India, from 2006 to 2015. Aerosol properties are investigated at monthly, seasonal, and annual scales. The monthly mean values of MODIS-derived AOD and AE were observed to be 0.18 (± 0.14) and 1.05 (± 0.43) respectively over the Dehradun region. The seasonal maximums in AOD with MODIS and MISR were observed as 0.23 ± 0.06 and 0.29 ± 0.07 respectively in the pre-monsoon season, and the minimum values (0.099 ± 0.02) were observed in the post-monsoon season, over the Dehradun region. In contrast, in the Chamoli region, the maximum AOD (MODIS) was 0.21 ± 0.06 observed in the monsoon season and the minimum was 0.036 ± 0.007 in the post-monsoon season. Over a decade, the AE for Chamoli and Dehradun was found to vary from 0.07 to 0.17 and from 0.14 to 0.20 respectively. The median AE for Chamoli and Dehradun was found to be 1.49 and 1.47 respectively, marking the dominance of fine mode particles of anthropogenic origin. Observations show the presence of dust and polluted dust resulting from the long-range transport from the west. The comparison of AOD values from the two sensors shows a significant correlation (0.73) with slightly higher values from MISR over the year. The results obtained are important in understanding the climatic implications due to the atmospheric aerosols over the abovementioned Himalayan region of Uttarakhand, India.


Assuntos
Atmosfera , Monitoramento Ambiental , Aerossóis/análise , Poeira/análise , Índia
2.
Mitochondrial DNA B Resour ; 3(2): 707-712, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-33490532

RESUMO

In the present study, we sequenced the individuals of the Danaus chrysippus from the different altitudinal ranges in the western Himalayan state of Uttarakhand, India and compared with other global published data across its distribution range using the cytochrome oxidase c subunit-I (COI). Among the sequences generated in this study, we observed total six haplotypes with intra-species sequence divergence of 0.001-0.009. Whereas the combined data generated a total of 24 haplotypes. The genetic diversity and neutrality test indices suggested overall population expansion of the species. This has also been supported by the MJ Network as it shows the star-like topology and formation of one core haplotype with maximum frequency distribution to the multiple locations. Whereas, the phylogenetic tree shows mixing of the haplotype from the different locations to the same clade. Haplotype arrangement in both phylogenetic tree and MJ Network is not clustered as per their geographic affinity, which suggests incomplete lineage shorting and recent population expansion or colonizations to the new area.

3.
Indian J Pharmacol ; 49(6): 419-431, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29674796

RESUMO

OBJECTIVE: The objective of the study was to explore the prescribing practices, knowledge, and attitudes of primary care doctors and community pharmacists, regarding antibiotic use in acute upper respiratory tract infections (URTI) and diarrhea in children to better understand causes of misuse and identify provider suggestions to change such behavior. MATERIALS AND METHODS: Two focus group discussions (FGDs) each were conducted with primary care government doctors (GDs), private general practitioners (GPs), pediatricians, and community pharmacists in Delhi. Each FGD had 8-12 participants and lasted 2 h. Furthermore, 22 individual face-to-face semi-structured interviews were conducted with providers of varying type and experience at their workplaces. Thematic and summative qualitative content analysis was done. RESULTS: All groups admitted to overusing antibiotics, GPs appearing to use more antibiotics than GDs and pediatricians for URTI and diarrhea in children. Pharmacists copy the prescribing of neighborhood doctors. Antimicrobial resistance (AMR) knowledge was poor for all stakeholders except pediatricians. Causes for prescribing antibiotics were patient pressure, profit motive, lack of follow-up and in addition for GDs, workload, no diagnostic facility, and pressure to use near-expiry medicines. Knowledge was gained through self-experience, copying others, information from pharmaceutical companies, and for some, training, continuous medical education/conferences. All groups blamed other professional groups/quacks for antibiotic overuse. Interventions suggested were sensitizing and empowering prescribers through training of providers and the public about the appropriate antibiotic use and AMR and implementing stricter regulations. CONCLUSIONS: A package of interventions targeting providers and consumers is urgently needed for awareness and change in behavior to reduce inappropriate community antibiotic use.


Assuntos
Antibacterianos/uso terapêutico , Diarreia/tratamento farmacológico , Prescrição Inadequada/prevenção & controle , Farmacêuticos/tendências , Padrões de Prática Médica/tendências , Uso Indevido de Medicamentos sob Prescrição/prevenção & controle , Infecções Respiratórias/tratamento farmacológico , Doença Aguda , Antibacterianos/administração & dosagem , Criança , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Prescrição Inadequada/estatística & dados numéricos , Índia , Uso Indevido de Medicamentos sob Prescrição/estatística & dados numéricos , Pesquisa Qualitativa , Inquéritos e Questionários
4.
Indian J Pharmacol ; 48(4): 365-371, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27756945

RESUMO

OBJECTIVE: To explore the perceptions and knowledge of school teachers and students about antibiotic use, resistance, and suggestions for practical interventions for the rational use of antibiotics. METHODOLOGY: Five focus group discussions (FGDs) with high school students (Class: 9-11) and five with teachers were conducted in two private and three public schools (one teacher and one student FGD per school) in five municipal wards of Delhi. Qualitative data on antibiotic knowledge, resistance, and behaviors with respect to antibiotics use were collected. There were 4-8 persons per teacher FGD and 15-20 persons per student FGD. FGDs were analyzed using "thematic analyses." RESULTS: Students had poor knowledge regarding antibiotics and antibiotic resistance, while only some teachers had a basic understanding. Four broad themes needing attention emerged: definition of antibiotic and antibiotic resistance, antibiotic use behavior, doctor-patient relationship, and interventional strategies suggested to curtail the misuse of antibiotics and to spread awareness. In order to tackle these problems, both groups suggested a multipronged approach including robust public awareness campaigns also involving schools, better doctor-patient relationships, and stronger regulations. CONCLUSIONS: Although students and teachers exhibited poor knowledge about antibiotic use and resistance, they were keen to learn about these issues. School education programs and public education could be used to shape correct perceptions about antibiotic use among all stakeholders including children. This may help in the containment of antibiotic resistance and thus preservation of antibiotics for future generations.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Serviços Comunitários de Farmácia , Farmacorresistência Bacteriana/efeitos dos fármacos , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Antibacterianos/economia , Antibacterianos/provisão & distribuição , Grupos Focais , Humanos , Índia , Uso Indevido de Medicamentos sob Prescrição , Medicamentos sob Prescrição/efeitos adversos , Medicamentos sob Prescrição/economia , Medicamentos sob Prescrição/provisão & distribuição , Medicamentos sob Prescrição/uso terapêutico , Pesquisa Qualitativa , Instituições Acadêmicas , Automedicação/psicologia , Automedicação/estatística & dados numéricos , Estudantes/psicologia , Inquéritos e Questionários
5.
J Biosoc Sci ; 47(4): 554-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26199968

RESUMO

Central obesity has been associated with the risk of cardiovascular and metabolic disease in children. A total of 358 Delhi school girls aged 6­11 years were measured for height, weight, waist circumference and hip circumference. The study demonstrates a linear correlation between body mass index (BMI) and waist and hip circumference and suggests an indirect method of estimating waist and hip circumferences, whose high values may be used for the diagnosis of metabolic syndrome and cardiovascular disease. Further investigations on different groups are needed to substantiate these results and attribute BMI a predictive value in the clinical setting for the risk and diagnosis of childhood obesity-related metabolic disorders.


Assuntos
Índice de Massa Corporal , Circunferência da Cintura , Estatura , Peso Corporal , Criança , Feminino , Humanos , Índia , Obesidade Infantil/complicações , Obesidade Infantil/diagnóstico , Obesidade Infantil/etiologia , Análise de Regressão , Fatores de Risco , Relação Cintura-Quadril
6.
J Clin Pharm Ther ; 37(3): 308-12, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21883328

RESUMO

WHAT IS KNOWN AND OBJECTIVE: The overall volume of antibiotic consumption in the community is one of the foremost causes of antimicrobial resistance. In developing countries like India, pharmacists often dispense 'prescription-only' drugs, like antibiotics, to patients who do not have a prescription. Not much data is available regarding detailed information on behaviour of antibiotic use by community pharmacists which is of particular significance to develop a suitable and sustainable intervention programme to promote rational use of antibiotics. A qualitative study was conducted to understand the dispensing practices and behaviour of community pharmacists to develop policy interventions that would improve the use of antibiotics at the community level. METHODS: Focus group discussions (FGDs) were held for five municipal wards of Delhi with retail pharmacists, public sector pharmacists and the office bearers of pharmacists' associations. Data on antibiotic use and resistance were collected earlier from these five wards. FGDs (n = 3 with 40 pharmacists) were analysed through grounded theory. RESULTS AND DISCUSSION: Four broad themes identified were as follows: prescribing and dispensing behaviour; commercial interests; advisory role; and intervention strategies for rational use of antibiotics. FGDs with pharmacists working in the public sector revealed that, besides the factors listed above, overstock and near-expiry, and under-supply of antibiotics promoted antibiotic misuse. Suggestions for interventions from pharmacists were the following: (i) education to increase awareness of rational use and resistance to antibiotics; (ii) involving pharmacists as partners for creating awareness among communities for rational use and resistance to antibiotics; (iii) developing an easy return policy for near-expiry antibiotics in public sector facilities; and (iv) motivating and showing appreciation for community pharmacists who participate in intervention programmes. WHAT IS NEW AND CONCLUSIONS: Inappropriate antibiotic dispensing and use owing to commercial interests and lack of knowledge about the rational use of antibiotics and antibiotic resistance were the main findings of this in-depth qualitative study. Community pharmacists were willing to participate in educational programme aimed at improving use of antibiotics. Such programmes should be initiated within a multidisciplinary framework including doctors, pharmacists, social scientists, government agencies and non-profit organizations.


Assuntos
Antibacterianos/efeitos adversos , Farmacorresistência Bacteriana/efeitos dos fármacos , Mau Uso de Serviços de Saúde , Farmacêuticos , Papel Profissional , Automedicação/efeitos adversos , Antibacterianos/economia , Antibacterianos/provisão & distribuição , Antibacterianos/uso terapêutico , Serviços Comunitários de Farmácia/economia , Serviços Comunitários de Farmácia/ética , Crime/economia , Crime/etnologia , Países em Desenvolvimento , Educação em Farmácia , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Mau Uso de Serviços de Saúde/economia , Humanos , Índia , Medicamentos sem Prescrição/efeitos adversos , Medicamentos sem Prescrição/economia , Medicamentos sem Prescrição/provisão & distribuição , Medicamentos sem Prescrição/uso terapêutico , Educação de Pacientes como Assunto , Farmacêuticos/ética , Medicamentos sob Prescrição/efeitos adversos , Medicamentos sob Prescrição/economia , Medicamentos sob Prescrição/provisão & distribuição , Medicamentos sob Prescrição/uso terapêutico , Pesquisa Qualitativa , Automedicação/economia , Automedicação/ética , Sociedades Farmacêuticas , População Urbana
7.
Indian J Med Res ; 134: 281-94, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21985810

RESUMO

Antibiotic resistance, a global concern, is particularly pressing in developing nations, including India, where the burden of infectious disease is high and healthcare spending is low. The Global Antibiotic Resistance Partnership (GARP) was established to develop actionable policy recommendations specifically relevant to low- and middle-income countries where suboptimal access to antibiotics - not a major concern in high-income countries - is possibly as severe a problem as is the spread of resistant organisms. This report summarizes the situation as it is known regarding antibiotic use and growing resistance in India and recommends short and long term actions. Recommendations aim at (i) reducing the need for antibiotics; (ii) lowering resistance-enhancing drug pressure through improved antibiotic targeting, and (iii) eliminating antibiotic use for growth promotion in agriculture. The highest priority needs to be given to (i) national surveillance of antibiotic resistance and antibiotic use - better information to underpin decisions on standard treatment guidelines, education and other actions, as well as to monitor changes over time; (ii) increasing the use of diagnostic tests, which necessitates behavioural changes and improvements in microbiology laboratory capacity; (iii) setting up and/or strengthening infection control committees in hospitals; and (iv) restricting the use of antibiotics for non-therapeutic uses in agriculture. These interventions should help to reduce the spread of antibiotic resistance, improve public health directly, benefit the populace and reduce pressure on the healthcare system. Finally, increasing the types and coverage of childhood vaccines offered by the government would reduce the disease burden enormously and spare antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos , Uso de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/tendências , Política de Saúde/legislação & jurisprudência , Infecção Hospitalar/microbiologia , Uso de Medicamentos/legislação & jurisprudência , Índia , Política Pública
8.
Fam Pract ; 27(6): 684-90, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20660529

RESUMO

BACKGROUND: it is necessary to understand physician's prescribing behaviour in order to develop interventions that will effectively improve the use of antibiotics. OBJECTIVE: to explore the factors that influence primary care physicians to prescribe antibiotics and to investigate possible interventions. METHODS: focus group discussions (FGDs) were used to explore the perspectives of primary care physicians in the public and private sectors from five municipal wards (residential localities) of Delhi from where data on antibiotic use and resistance were collected. FGDs (n = 3 with 36 prescribers) were analysed through grounded theory. RESULTS: three broad themes identified were as follows: behavioural characteristics of doctors and patients; laxity in regulation of prescribing and dispensing antibiotics and intervention strategies to decrease misuse of, and resistance to, antibiotics. Important factors identified for antibiotic prescriptions by doctors were diagnostic uncertainty, perceived demand and expectation from the patients, practice sustainability and financial considerations, influence from medical representatives and inadequate knowledge. For public sector doctors, besides the above, overstocked and near-expiry drugs and lack of time were the factors that promoted antibiotic overuse. Doctors also identified certain patient behaviour characteristics and laxity in regulation for prescribing and dispensing of antibiotics as aggravating the problem of antibiotic misuse. Interventions like Continuing Medical Educations for doctors, awareness raising of patients, shared decision making and stricter rules and regulations were suggested to promote rational use of antibiotics in the community. CONCLUSION: exploration of doctors' antibiotic use practices and possible interventions will be helpful in carrying out interventions to promote appropriate use of antibiotics in the community.


Assuntos
Antibacterianos/uso terapêutico , Prescrições de Medicamentos , Relações Médico-Paciente , Médicos de Atenção Primária , Padrões de Prática Médica , Atitude do Pessoal de Saúde , Tomada de Decisões , Humanos , Índia , Incerteza
9.
J Environ Biol ; 30(2): 295-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20121034

RESUMO

Changes in the concentration of different photosynthetic pigments (Chlorophyll and carotenoids) were determined in the leaves of six tree species exposed to air pollution due to vehicular emissions. The six tree species, which are all economically important because of their being fruit bearers, used for timber fodder and as road side trees on the basis of their air pollution tolerance index. These included Mangifera indica L., Tectona grandis Linn.f , Shorea robusta Gaertn.f., Holoptelea integrifolia (Roxb.) Planch, Eucalyptus citridora Hook. Syn. and Mallotus philippinensis Muell-Arg. Reduction in chlorophyll 'a', 'b' and carotenoid was recorded in the leaf samples collected from polluted areas when compared with samples from control areas. The highest reduction in total chlorophyll was observed in Holoptelea integrifolia (Roxb.) (48.73%) Planch whereas, the lowest reduction (17.84 %) was recorded in Mallotus philippinensis Muell-Arg. Similarly in case of carotenoid contents, highest reduction (43.02%) was observed in Eucalyptus citridora, and lowest in Mallotus philippinensis Muell-Arg (19.31%). The data obtained were further analyzed using one-way ANOVA and a significant change was recorded in the studied parameters. These studies clearly indicate that the vehicular induced air pollution reduces the concentration of photosynthetic pigments in the trees exposed to road side pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Fotossíntese , Pigmentos Biológicos/metabolismo , Plantas/efeitos dos fármacos , Plantas/metabolismo , Especificidade da Espécie
10.
Biol Trace Elem Res ; 92(3): 257-74, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12794277

RESUMO

Soil contamination with heavy metals has become a worldwide problem, leading to losses in agricultural yield and hazardous human health effects as they enter the food chain. The present investigation was undertaken to examine the influence of cadmium (Cd2+) on the wheat (Triticum aestivum L.) plant. Cd2+ accumulation and distribution in 3-wk-old seedlings grown in nutrient medium containing varying concentrations of Cd2+ (control, 0.25, 0.50, 1.0, 2.5, and 5.0 mg/L) was monitored. The effect of varying Cd2+ concentrations up to 21 d on biomass productivity, plant growth, photosynthetic pigments, protein, amino acids, starch, soluble sugars, and essential nutrients uptake was studied in detail to explore the level up to which the plant can withstand the stress of heavy metal. Plants treated with 0.5, 1.0, 2.5, and 5.0 mg/L Cd2+ showed symptoms of heavy-metal toxicity as observed by various morphological parameters which were recorded with the growth of plants. The root, shoot-leaf length and the root, shoot-leaf biomass progressively decreased with increasing Cd2+ concentration in the nutrient medium. Cd2+ uptake and accumulation was found to be maximum during the initial growth period. Cd2+ also interfered with the nutrients uptake, especially calcium (Ca2+), magnesium (Mg2+), potassium (K+), iron (Fe2+), zinc (Zn2+), and manganese (Mn2+) from the growth medium. Growth reduction and altered levels of major biochemical constituents such as chlorophyll, protein, free amino acids, starch, and soluble sugars that play a major role in plant metabolism were observed in response to varying concentrations of Cd2+ in the nutrient medium. In the present study, the effects of Cd2+ on growth, biomass productivity, mineral nutrients, chlorophyll biosynthesis, protein, free amino acid, starch, and soluble sugars in wheat plants was estimated to establish an overall picture of the Cd2+ toxicity at structural and functional levels.


Assuntos
Cádmio/metabolismo , Cádmio/toxicidade , Clorofila/biossíntese , Oligoelementos/metabolismo , Triticum/metabolismo , Aminoácidos/metabolismo , Biomassa , Carboidratos/biossíntese , Proteínas de Plantas/biossíntese , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Amido/biossíntese , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
11.
J Environ Monit ; 4(3): 449-51, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12094943

RESUMO

Pentachlorophenol (PCP), a fungicide and insecticide, leaves behind considerable residue in the environment in the form of unreacted molecule, metabolites and photoreduction products. Most of the previously reported photoproducts have resulted from dechlorination of the parent molecule. We have shown that photoreduction of PCP also proceeds by photoreduction of the parent molecule at carbons 2 and 4. These products were identified and characterized as 2-dehydro-2,3,4,5,6-pentachlorocyclohexanone (II) and 2,3,4,5,6-pentachlorocyclohexanone (IV). Both of them display keto-enol tautomerism. Identification and characterization of new photoproducts of PCP is significant for determining its overall environmental impact in the ecosystem.


Assuntos
Poluentes Ambientais/análise , Pentaclorofenol/análise , Monitoramento Ambiental , Isomerismo , Oxirredução , Pentaclorofenol/análogos & derivados , Pentaclorofenol/química , Fotoquímica
12.
Drug Chem Toxicol ; 25(2): 215-25, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12024804

RESUMO

Photosensitization reaction of drugs leading to the formation of reactive oxygen species under ultraviolet radiation (UVR) can cause tissue injury, resulting in damage to various cellular macromolecules. The aim of this study was to determine the singlet oxygen generation potential of some commonly used antibiotics so that due precautions can be exercised to minimize their photosensitizing action and oxidative stress potential. The selected antibiotics were examined for their ability to produce singlet oxygen (1O2) under artificial UVA (320-400 nm). Singlet oxygen generation of various screened antibiotics under UVA is of the following order: Nalidixic acid > Amphotericin-B > Cephradine > Cefazolin > Nafcillin > Cephalothin > Ampicillin > Cephalexin > Puromycin > Kanamycin > Lincomycin > Tetracycline > Nystatin > Gentamicin sulphate. Nalidixic acid, the most potent generator of 1O2 among the screened antibiotics, was selected to carry out further studies. Certain specific quenchers of 1O2 such as beta-carotene, 1,4-diazabicyclo[2.2.2] octane (DABCO), and sodium azide (NaN3) accorded significant inhibition in the production of 1O2. The results suggest that precautions are necessary to avoid ultraviolet radiation after the intake of photoreactive drugs, especially in tropical countries such as India. These findings are significant because UVB radiation is reportedly increasing on earth surface in part due to depletion of stratospheric ozone layer. The selected drugs are commonly used for the treatment of various diseases. Thus, the synergistic action of both can lead to undesirable phototoxic responses.


Assuntos
Antibacterianos/efeitos da radiação , Oxigênio Singlete/química , Relação Dose-Resposta a Droga , Técnicas In Vitro , Fotoquímica , Oxigênio Singlete/análise , Raios Ultravioleta
13.
Drug Chem Toxicol ; 24(2): 191-200, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11360435

RESUMO

Photosensitization reaction of drugs leading to the formation of reactive oxygen species (ROS) cause tissue injury causing damage to various cellular macromolecules. The aim of this study was to determine the superoxide anion (O2-) generation potential of commonly used antibiotics so that due precaution could be exercised to minimize their photosensitizing action and oxidative stress potential. The selected antibiotics were examined for their ability to produce (O2-) under sunlight and artificial UVA (320-400 nm) and UVB (290-320 nm). Lincomycin, cephalothin and erythromycin generated significant amount of O2- under various irradiation conditions. Superoxide dismutase (SOD), an enzymatic quencher of O2- inhibited O2- production in all drugs tested. The results suggest that due precaution are necessary to avoid ultraviolet radiation (UVR) after the intake of photoreactive drugs, especially in tropical and sub tropical countries.


Assuntos
Antibacterianos/efeitos da radiação , Radicais Livres/metabolismo , Cefalotina/metabolismo , Clima , Eritromicina/metabolismo , Humanos , Fotoquímica , Superóxidos/análise , Raios Ultravioleta
14.
Food Chem Toxicol ; 39(1): 11-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11259847

RESUMO

Riboflavin (RF) is a known photoreactive and phototoxic molecule. However, unlike other photosensitizers, it does not induce photohaemolysis of erythrocytes by itself. On the other hand, illuminated RF caused haemolysis but in the presence of serum or plasma. The kinetics of photohaemolysis in the presence of serum/plasma has been studied by monitoring the rate of haemolysis spectrophotometrically and morphological changes at erythrocytes membrane by scanning electron microscopy. We found that the extent of mammalian RBC membrane damage was dependent on the concentration of RF or hematoporphyrin (HP) (0-20 microgram/ml) and dose of sunlight (0-20 min). The RBC membrane-damaging potential of illuminated HP was not affected by the presence of plasma in the reaction system. Furthermore, RF showed a protective role against photohaemolysis caused by photoexcited HP if erythrocytes were preincubated with RF in the absence of serum/plasma. For mechanistic studies, biochemical parameters such as acetylcholinesterase activity (AChE) and formation of TBA-reactive substance (TBA-RS) were analysed in RBC and RBC+plasma under a similar set of experimental conditions. We observed about a 25% decrease in AchE activity as a synergistic action of RF or HP (20 microgram/ml) and sunlight (30 min) in both cases (RBC or RBC+plasma). Interestingly, illuminated RF caused about a 125% increase of TBA-RS in a reaction system consisting of RBC+plasma. On the other hand, an increase in the production of TBA-RS by illuminated RF was not observed in the absence of plasma/serum, in the reaction system. These results suggested that photooxidation of RBC membrane lipids by illuminated RF, under the influence of plasma/serum, may be one of the causes of membrane modification leading to RBC lysis.


Assuntos
Acetilcolinesterase/metabolismo , Membrana Eritrocítica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Riboflavina/farmacologia , Luz Solar , Animais , Membrana Eritrocítica/ultraestrutura , Eritrócitos , Hematoporfirinas , Técnicas In Vitro , Cinética , Peróxidos Lipídicos/sangue , Camundongos , Microscopia Eletrônica de Varredura , Ratos , Dosimetria Termoluminescente , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Ecotoxicol Environ Saf ; 48(2): 219-21, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11161698

RESUMO

The effect of lindane was studied in Cyanobacteria (Anabaena) by estimating its growth pattern, biomass yield, chlorophyll content, and total starch and protein content. The results reveal that exposure of Anabaena with 0.5, 1.0, 1.5, and 2.0 ppm levels of lindane will have drastic effects on biomass production and photosynthetic rate. Since Cyanobacteria are a primary source of aquatic food web and important biofertilizer for rice cultivation, their protection from residual effects of lindane is essential for enriched soil fertility.


Assuntos
Anabaena/fisiologia , Cianobactérias/efeitos dos fármacos , Hexaclorocicloexano/toxicidade , Inseticidas/toxicidade , Proteínas de Algas/metabolismo , Clorofila/metabolismo , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/metabolismo , Amido/metabolismo
16.
J Immunol ; 166(2): 885-91, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11145664

RESUMO

NK cell function is regulated by cytokines and certain biochemical mediators in a positive or negative manner. This study was performed to investigate the suppressive effects of PGE(2) on IL-15-activated human NK cell function. Purified NK cells were cultured with 200 ng/ml IL-15 for 2 days in the presence or absence of 10-200 ng/ml PGE(2). PGE(2) significantly suppressed NK cell-mediated cytotoxicity and IFN-gamma production at the secretional and the transcriptional levels. We also evaluated the effect of PGE(2) on the IL-15R complex that consists of IL-2Rbeta, common gamma-chain (gamma(c)-chain), and a specific chain IL-15Ralpha. Percentage of positive cells and number of binding sites for gamma(c)-chain were significantly increased after IL-15 treatment; however, a substantial decrease was observed with PGE(2) cotreatment. In contrast, constitutive expression of IL-2Rbeta was significantly decreased after IL-15 treatment, with no change detected in the presence of PGE(2.) At the transcriptional level, neither IL-15 nor PGE(2) had significant effects on the expression of beta- or gamma(c)-chains. There was a 3-fold increase in the expression of IL-15Ralpha at the transcriptional level that peaked at 8 h after IL-15 treatment; however, PGE(2) had no significant effect. Suppression of NK function by PGE(2) was not due to the endogenous production of IL-4, IL-10, or TGF-beta(1) by NK cells. These results suggest that down-regulation of surface expression of gamma(c)-chain on NK cells may be one mechanism through which PGE(2) mediates suppression of IL-15-activated NK cell function.


Assuntos
Dinoprostona/farmacologia , Regulação para Baixo/imunologia , Imunossupressores/farmacologia , Interleucina-15/antagonistas & inibidores , Interleucina-15/fisiologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Receptores de Interleucina-7/antagonistas & inibidores , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Interferon gama/antagonistas & inibidores , Interferon gama/biossíntese , Interferon gama/genética , Subunidade gama Comum de Receptores de Interleucina , Ativação Linfocitária/efeitos dos fármacos , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , Receptores de Interleucina-15 , Receptores de Interleucina-2/biossíntese , Receptores de Interleucina-2/genética , Receptores de Interleucina-7/biossíntese , Receptores de Interleucina-7/genética
18.
Res Commun Mol Pathol Pharmacol ; 107(1-2): 13-20, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11334363

RESUMO

Macrophage migration inhibitory factor (MIF) is a pituitary "stress" hormone that plays a critical role in the host immune response. The aims of the study were to determine whether MIF was detectable in the circulation of trauma patients, to assess whether MIF levels were associated with injury severity, days post injury, infection, and to examine concentrations of other pro-inflammatory cytokines in circulation. We collected plasma samples from 35 trauma (multiple injury) patients and 18 healthy controls. Concentrations of MIF, TNF-alpha, IL-1beta, and IL-6 were measured by ELISA. Average MIF concentration in plasma of trauma patients was 14 fold higher than that of healthy controls (19,439+/-2,615 pg/ml in trauma vs 1,337+/-286 pg/ml in control; p=0.0002). There was no correlation between MIF values and injury severity score or days post injury. Average level of IL-6 in trauma patients was 587+/-85 pg/ml but was not correlated with MIF concentration. TNF-alpha and IL-1beta were not detectable in trauma patients or healthy controls. Higher MIF levels were associated with positive cultures (blood, urine, sputum, wound). These data suggest that MIF may be a possible indicator of infection in trauma patients.


Assuntos
Infecções Bacterianas/imunologia , Fatores Inibidores da Migração de Macrófagos/análise , Traumatismo Múltiplo/imunologia , Infecções Bacterianas/microbiologia , Ensaio de Imunoadsorção Enzimática , Humanos , Escala de Gravidade do Ferimento , Interleucina-1/análise , Interleucina-1/imunologia , Interleucina-6/análise , Interleucina-6/imunologia , Fatores Inibidores da Migração de Macrófagos/sangue , Macrófagos/imunologia , Traumatismo Múltiplo/sangue , Traumatismo Múltiplo/complicações , Estatística como Assunto , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/imunologia
19.
J Biomol Struct Dyn ; 17 Suppl 1: 207-10, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-22607426

RESUMO

Abstract Progress towards the laboratory demonstration of the steps in the prebiotic origin of the RNA world is reviewed. Montmorillonite clay catalyzes the formation of RNAs containing 6-14 monomer units from the activated mononucleotides of A, C, G, I and U. The RNAs formed have 3', 5'- and 2', 5'-links, pyrophosphate links and have both linear and cyclic chains. The purine oligonucleotides have more 3', 5'- links while the pyrimidine nucleotides have more 2', 5'-linkages. Template-directed synthesis on the heterogeneous oligo(C)s formed on mont- morillonite yields the corresponding oligo(G)s. The dimer fraction formed in the reaction of a binary mixture of a purine and pyrimidine nucleotide shows sequence selectivity with about a 20 fold excess of the 5'-purine-pyrimidine dimer over that of the 5'-pyrimidine-purine dimer. RNAs as long as 50 mers are formed by the elongation of a decamer bound to montmorillonite by the daily addition of activated monomer to it over a 14-day time period.


Assuntos
Prebióticos , RNA , Bentonita , Catálise , Nucleotídeos , Oligonucleotídeos , Origem da Vida
20.
Food Chem Toxicol ; 37(8): 847-52, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10506008

RESUMO

Vegetables grown in the dry bed field of the River Ganga in Kanpur, an important industrial city of North India, were analysed for the pesticides hexachlorocyclohexane (HCH), dichlorodiphenyl trichloroethane (DDT), their isomers and metabolites at three different sites. Residues of both the pesticides were found in all the samples. Mean levels of 109.35, 136.76 and 145.93 microg HCH/kg and 6.64, 49.3 and 46.70 microg DDT/kg were found in the rural upstream, city and downstream industrial areas, respectively. The mean total HCH and DDT levels were within safe limits as per the Indian Standard but some samples had HCH levels above the WHO/FAO limit. The pesticide residue level in vegetables was several fold higher than their surrounding sandy soil and could pose health problems since these popular vegetables are consumed regularly by the population.


Assuntos
Produtos Agrícolas/química , Resíduos de Praguicidas/análise , Solo/análise , Verduras/química , Produtos Agrícolas/normas , DDT/análise , Dieta , Monitoramento Ambiental , Hexaclorocicloexano/análise , Humanos , Índia , Inseticidas/análise , Risco
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