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1.
Rev Sci Instrum ; 87(3): 033107, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27036758

RESUMO

To clarify the growth mechanism of a protein crystal, it is essential to measure its growth rate with respect to the supersaturation. We developed a compartment (growth cell) for measuring the growth rate (<0.1 nm s(-1)) of the face of a protein crystal at a controlled supersaturation by interferometry over a period of half a year in space. The growth cell mainly consists of quartz glass, in which the growth solution and a seed crystal are enclosed by capillaries, the screw sample holder, and a helical insert. To avoid the destruction of the cell and the evaporation of the water from the solution inside the cell, we selected the materials for these components with care. The equipment was successfully used to examine the growth of a lysozyme crystal at a controlled supersaturation in space, where convection is negligible because of the microgravity environment, thereby advancing our understanding of the mechanism of protein crystal growth from solution. The technique used to develop the growth cell is useful not only for space experiments but also for kinetic studies of materials with very slow growth and dissolution rates (<10(-3) nm s(-1)).


Assuntos
Cristalização/métodos , Meio Ambiente Extraterreno , Proteínas/química , Cinética
2.
Nat Commun ; 7: 10724, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26911442

RESUMO

Increasing atmospheric carbon dioxide (CO2) is the principal driver of anthropogenic climate change. Asia is an important region for the global carbon budget, with 4 of the world's 10 largest national emitters of CO2. Using an ensemble of seven atmospheric inverse systems, we estimated land biosphere fluxes (natural, land-use change and fires) based on atmospheric observations of CO2 concentration. The Asian land biosphere was a net sink of -0.46 (-0.70-0.24) PgC per year (median and range) for 1996-2012 and was mostly located in East Asia, while in South and Southeast Asia the land biosphere was close to carbon neutral. In East Asia, the annual CO2 sink increased between 1996-2001 and 2008-2012 by 0.56 (0.30-0.81) PgC, accounting for ∼35% of the increase in the global land biosphere sink. Uncertainty in the fossil fuel emissions contributes significantly (32%) to the uncertainty in land biosphere sink change.

3.
Chemosphere ; 95: 213-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24075529

RESUMO

Iron (Fe) is one of the vital limiting factors for phytoplankton in vast regions of the contemporary oceans, notably the high nutrient low chlorophyll regions. Therefore, it is apparent to be acquainted with the Fe uptake strategy of marine phytoplankton under Fe-limited condition. In the present study, marine phytoplankton Prymnesium parvum was grown under Fe-deplete (0.0025 µM) and Fe-rich (0.05 µM) conditions, and proteomic responses of the organism to Fe conditions were compared. In sodium dodecyl sulfate (SDS) gel electrophoresis, 7 proteins (16, 18, 32, 34, 75, 82, and 116 kDa) were highly expressed under Fe-deplete condition, while one protein (23 kDa) was highly expressed under Fe-rich condition. These proteins were subjected to 2-dimensional gel electrophoresis (2-D DIGE) to differentiate individual proteins, and were identified by matrix-assisted laser desorption-ionization-time of flight-mass spectrometer (MALDI-TOF-MS) analysis. The results showed that under Fe-deplete condition P. parvum increases the biosynthesis of ATP binding cassette (ABC) transporters, flagellar associated protein (FAP), and Phosphoribosylaminoimidazole-succinocarboxamide synthase. These proteins are assumed to be involved in a number of cellular biochemical processes that facilitate Fe acquisition in phytoplankton. Under Fe-deplete condition, P. parvum increases the synthesis of ribulose biphosphate carboxylase (RuBisCo), malate dehydrogenase, and two Fe-independent oxidative stress response proteins, manganese superoxide dismutase (MnSOD) and Serine threonine kinase (STK). Thus, marine phytoplankton may change their Fe acquisition strategy by altering the biosynthesis of several proteins in order to cope with Fe-limitation.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Aclimatação/fisiologia , Haptófitas/fisiologia , Ferro/metabolismo , Clorofila/metabolismo , Eletroforese em Gel Bidimensional , Oceanos e Mares , Estresse Oxidativo , Proteínas Serina-Treonina Quinases/metabolismo , Proteômica , Superóxido Dismutase/metabolismo , Regulação para Cima
4.
Phys Rev Lett ; 111(1): 012001, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-23862993

RESUMO

The TOTEM collaboration has measured the proton-proton total cross section at √s=8 TeV using a luminosity-independent method. In LHC fills with dedicated beam optics, the Roman pots have been inserted very close to the beam allowing the detection of ~90% of the nuclear elastic scattering events. Simultaneously the inelastic scattering rate has been measured by the T1 and T2 telescopes. By applying the optical theorem, the total proton-proton cross section of (101.7±2.9) mb has been determined, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections: σ(el)=(27.1±1.4) mb; σ(inel)=(74.7±1.7) mb.

5.
Br J Pharmacol ; 170(1): 177-87, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23489295

RESUMO

BACKGROUND AND PURPOSE: Conflicting data have been published on whether histamine is inhibitory to the rewarding effects of abused drugs. The purpose of this study was to clarify the role of neuronal histamine and, in particular, H3 receptors in alcohol dependence-related behaviours, which represent the addictive effects of alcohol. EXPERIMENTAL APPROACH: Alcohol-induced conditioned place preference (alcohol-CPP) was used to measure alcohol reward. Alcohol-induced locomotor stimulation, alcohol consumption and kinetics were also assessed. mRNA levels were quantified using radioactive in situ hybridization. KEY RESULTS: Low doses of H3 receptor antagonists, JNJ-10181457 and JNJ-39220675, inhibited alcohol reward in wild-type (WT) mice. However, these H3 receptor antagonists did not inhibit alcohol reward in histidine decarboxylase knock-out (HDC KO) mice and a lack of histamine did not alter alcohol consumption. Thus H3 receptor antagonists inhibited alcohol reward in a histamine-dependent manner. Furthermore, WT and HDC KO mice were similarly stimulated by alcohol. The expression levels of dopamine D1 and D2 receptors, STEP61 and DARPP-32 mRNA in striatal subregions were unaltered in HDC KO mice. No differences were seen in alcohol kinetics in HDC KO compared to WT control animals. In addition, JNJ-39220675 had no effect on alcohol kinetics in WT mice. CONCLUSIONS AND IMPLICATIONS: These data suggest that histamine is required for the H3 receptor-mediated inhibition of alcohol-CPP and support the hypothesis that the brain histaminergic system has an inhibitory role in alcohol reward. Increasing neuronal histamine release via H3 receptor blockade could therefore be a novel way of treating alcohol dependence.


Assuntos
Etanol/administração & dosagem , Histamina/metabolismo , Histidina Descarboxilase/genética , Receptores Histamínicos H3/metabolismo , Consumo de Bebidas Alcoólicas/metabolismo , Animais , Azepinas/administração & dosagem , Azepinas/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Etanol/farmacocinética , Etanol/farmacologia , Antagonistas dos Receptores Histamínicos H3/administração & dosagem , Antagonistas dos Receptores Histamínicos H3/farmacologia , Liberação de Histamina/fisiologia , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos DBA , Camundongos Knockout , Morfolinas/administração & dosagem , Morfolinas/farmacologia , Atividade Motora/efeitos dos fármacos , Neurônios/metabolismo , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Piridinas/administração & dosagem , Piridinas/farmacologia , RNA Mensageiro/metabolismo , Receptores Histamínicos H3/efeitos dos fármacos , Recompensa
6.
Phys Rev Lett ; 111(26): 262001, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24483791

RESUMO

The first double diffractive cross-section measurement in the very forward region has been carried out by the TOTEM experiment at the LHC with a center-of-mass energy of sqrt[s]=7 TeV. By utilizing the very forward TOTEM tracking detectors T1 and T2, which extend up to |η|=6.5, a clean sample of double diffractive pp events was extracted. From these events, we determined the cross section σDD=(116±25) µb for events where both diffractive systems have 4.7<|η|min<6.5.

7.
Bull Environ Contam Toxicol ; 88(5): 695-702, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22395199

RESUMO

Arsenic (As) contamination is an important environmental consequence in some parts of salinity-affected South (S) and South-East (SE) Asia. In this study, we investigated the individual and combined phytotoxicity of arsenic (As) [arsenate; As(V)] and salinity (NaCl) on early seedling growth (ESG) of saline-tolerant and non-tolerant rice varieties. Germination percentage (GP), germination speed (GS) and vigor index (VI) of both saline-tolerant and non-tolerant rice varieties decreased significantly (p > 0.01) with increasing As(V) and NaCl concentrations. The highest GP (91%) was observed for saline non-tolerant BRRI dhan28 and BRRI dhan49, while the lowest (62%) was for saline-tolerant BRRI dhan47. The ESG parameters, such as weights and relative lengths of plumule and radicle, also decreased significantly (p < 0.01) with increasing As(V) and NaCl concentrations. Relative radicle length was more affected than plumule length by As(V) and NaCl. Although VI of saline-tolerant and non-tolerant rice seedlings showed significant variation (p < 0.05), weights and lengths of plumule and radicle of different rice varieties did not show significant variation for As(V) and NaCl treatments. Results reveal that the combined phytotoxicity of As(V) and NaCl on rice seed germination and ESG are greater than their individual toxicities, and some saline-tolerant rice varieties are more resistant to the combined phytotoxicity of As(V) and NaCl than the saline non-tolerant varieties.


Assuntos
Arseniatos/toxicidade , Oryza/efeitos dos fármacos , Salinidade , Plântula/efeitos dos fármacos , Poluentes do Solo/toxicidade , Agricultura/métodos , Sudeste Asiático , Bangladesh , Conservação dos Recursos Naturais , Germinação/efeitos dos fármacos , Água Subterrânea/química , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Solo/química
8.
Jpn J Nurs Sci ; 8(1): 33-46, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21615696

RESUMO

AIM: The early resignation of newly graduated nurses (NGNs) will become a concern in Japan as the need for nurses increases. The aim of this study was to conduct an investigation using the Effort-Reward Imbalance (ERI) questionnaire to examine the effect of stressful experiences in the work environment and over-commitment on NGNs' intention to leave and to identify the factors that were associated with their intention to leave, clarifying the appropriate times at which to conduct interventions to prevent NGNs from leaving advanced-treatment hospitals. METHODS: Anonymous self-administered questionnaires were distributed to all the NGNs (n = 1364) in 14 advanced-treatment university hospitals. Questionnaires with no missing data were returned by 737 NGNs (54%). For the development of the questionnaire, we designed a framework that consisted of the factors that occur during three stages of the NGNs' transition into the workplace. The questions addressed items for individual attributes, employment and organizational characteristics, the Role Model Scale, the ERI questionnaire, two scale items for health status, and the intention to leave. In order to determine the factors that related to the dependent variables, hierarchical multiple linear regression analyses were carried out. RESULTS: We revealed that effort, subjective health status, role models, and effort were important factors that related to the NGNs' intention to leave, as well as their age and city size. Over-commitment and reward were not significant factors. We also found that three subscales of the Job Readiness Scale independently related to the NGNs' intention to leave. CONCLUSION: These findings can help employers, supervisors, and senior staff of advanced-treatment university hospitals in Japan to improve their work environment in order to benefit NGNs and aid in their retention.


Assuntos
Recursos Humanos de Enfermagem no Hospital/psicologia , Humanos , Japão
9.
Chemosphere ; 84(4): 439-45, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21507453

RESUMO

This study was conducted to investigate the effect of external iron status and arsenic species on chelant-enhanced iron bioavailability and arsenic uptake. Rice seedlings (Oryza sativa L.) were used as model plant, and were grown in artificially contaminated sandy soils irrigated with Murashige and Skoog (MS) culture solution. Arsenate uptake in roots and shoots of rice seedlings were affected significantly (p>0.05) while dimethylarsinic acid (DMAA) was not by the additional iron and chelating ligand treatments. Regardless of iron concentrations in the soil solution, HIDS increased arsenic uptake for roots more than EDTA and EDDS. Chelating ligands and arsenic species also influenced iron uptake in rice roots. Irrespective of arsenic species, HIDS was found to be more effective in the increase of iron bioavailability and uptake in rice roots compared to other chelants. There was a significant positive correlation (r=0.78, p<0.05) between arsenate and iron concentrations in the roots of rice seedlings grown with or without additional iron indicating that arsenate inhibit iron uptake. In contrast, there was no correlation between iron and DMAA uptake in roots. Poor correlation between iron and arsenic in shoots indicated that iron uptake in shoots was neither affected by additional iron nor by arsenic species. Compared to the control, chelating ligands increased iron uptake in shoots of rice seedlings significantly (p<0.05). Regardless of additional iron and arsenic species, iron uptake in rice shoots did not differed among EDTA, EDDS, and HIDS treatments.


Assuntos
Arsênio/metabolismo , Ferro/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Arsênio/análise , Arsênio/química , Ácido Cacodílico/análise , Ácido Cacodílico/química , Ácido Cacodílico/metabolismo , Quelantes/química , Recuperação e Remediação Ambiental/métodos , Ferro/análise , Ferro/química , Raízes de Plantas/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/química
10.
Am J Transplant ; 10(11): 2421-30, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20977633

RESUMO

Ischemia/reperfusion injury and delayed graft function (DGF) following organ transplantation adversely affect graft function and survival. A large animal model has not been characterized. We developed a pig kidney allograft model of DGF and evaluated the cytoprotective effects of inhaled carbon monoxide (CO). We demonstrate that donor warm ischemia time is a critical determinant of DGF as evidenced by a transient (4-6 days) increase in serum creatinine and blood urea nitrogen following transplantation before returning to baseline. CO administered to recipients intraoperatively for 1 h restored kidney function more rapidly versus air-treated controls. CO reduced acute tubular necrosis, apoptosis, tissue factor expression and P-selectin expression and enhanced proliferative repair as measured by phosphorylation of retinol binding protein and histone H3. Gene microarray analyses with confirmatory PCR of biopsy specimens showed that CO blocked proinflammatory gene expression of MCP-1 and heat shock proteins. In vitro in pig renal epithelial cells, CO blocks anoxia-reoxygenation-induced cell death while promoting proliferation. This large animal model of DGF can be utilized for testing therapeutic strategies to reduce or prevent DGF in humans. The efficacy of CO on improving graft function posttransplant validates the model and offers a potentially important therapeutic strategy to improve transplant outcomes.


Assuntos
Monóxido de Carbono/uso terapêutico , Função Retardada do Enxerto/tratamento farmacológico , Transplante de Rim/fisiologia , Animais , Monóxido de Carbono/farmacocinética , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Perfilação da Expressão Gênica , Rejeição de Enxerto/prevenção & controle , Rim/metabolismo , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/imunologia , Traumatismo por Reperfusão/prevenção & controle , Suínos , Tacrolimo/farmacocinética
11.
Br Poult Sci ; 51(3): 409-18, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20680876

RESUMO

1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides. 2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg(-1) karaya saponin and R. capsulatus 200 and 400 mg kg(-1) were used as treatment groups. 3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg(-1)+ R. capsulatus 400 mg kg(-1) exhibited the greatest reduction of serum (325%) and yolk (225%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation. 4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.


Assuntos
Galinhas/metabolismo , Colesterol/metabolismo , Gema de Ovo/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Probióticos/farmacologia , Rhodobacter capsulatus , Saponinas/farmacologia , Sterculia/química , Ração Animal , Animais , Galinhas/sangue , Colesterol/sangue , Dieta/veterinária , Gema de Ovo/metabolismo , Feminino , Óvulo/metabolismo , Saponinas/isolamento & purificação , Triglicerídeos/sangue , Triglicerídeos/metabolismo
12.
Sci Total Environ ; 408(7): 1684-90, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20067851

RESUMO

In this study, the influence of eutrophication on arsenic speciation in lake waters was investigated. Surface water samples (n=1-10) were collected from 18 lakes in Japan during July 2007 and February 2008. The lakes were classified into mesotrophic (7 lakes) and eutrophic (11 lakes) based on the total phosphate (T-P) and chlorophyll-a (Chl-a) concentrations in water column. Inorganic, methylated and ultraviolet-labile fractions of arsenic species were determined by combining hydride generation atomic absorption spectrometry with ultraviolet irradiation. Organoarsenicals (mainly methylated and ultraviolet-labile fractions) comprised 30-60% of the total arsenic in most lakes during summer. On the other hand, inorganic arsenic species (As(III+V)) dominates (about 60-85%) during winter. The occurrence of ultraviolet-labile fractions of arsenic was higher in eutrophic lakes than those in mesotrophic lakes in both seasons. The concentration of dimethyl arsenic (DMAA) was high in eutrophic lakes during winter; and in mesotrophic lakes during summer. The results suggest that the conversion of As(III+V) to more complicated organoarsenicals occurred frequently in eutrophic lakes compared to that in mesotrophic lakes, which is thought to be the influence of biological activity in the water column. The distribution of arsenic species were well correlated with phosphate concentrations than those of Chl-a. This might be due to the competitive uptake of As(V) and phosphate by phytoplankton. The organoarsenicals (OrgAs)/As(V) ratio was higher at low phosphate concentration indicating that conversion of As(V) to OrgAs species was more active in phosphate-exhausted lakes with high phytoplankton density.


Assuntos
Arsênio/química , Eutrofização , Estações do Ano , Água Doce
13.
Transfus Med ; 20(1): 30-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19788506

RESUMO

Descriptive information on platelet (PLT) recipients, particularly during surgery, is limited. A description of the current epidemiology of PLT-transfused patients is required to optimize platelet transfusion care and to follow trends in PLT use. In 2004 and 2005, information was combined from several computerized medical systems. Participating hospitals (9 hospital districts of 21) handled approximately 64% of annual Finnish hospital admissions. A total of 6321 adult patients were transfused with 37,761 PLT products. Most PLT products (43.1%) were transfused to patients suffering from haematological malignancies. Only 1.0% of all surgical patients received PLTs (53.8% of PLT recipients and 35.8% of transfused PLTs). The most common single operation connected with PLT transfusion was coronary artery bypass while 27.1% of surgery-related PLTs were given to patients having an operation involving the digestive system or spleen. Only 36.4% of all PLT-transfused (operated and conservatively treated) patients were discharged directly home; in-hospital mortality was 9.5%. PLTs were given 40 products per 1000 hospital admissions requiring an operation in 2004, and 38 products in 2005. Perioperative PLT use is slightly decreasing in adult patients. As a single-operation type, coronary artery bypass patients receive most of the PLT products and have experienced no decline in PLT use over the years. Overall, PLT recipients have high in-hospital mortality.


Assuntos
Transfusão de Plaquetas/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupos Diagnósticos Relacionados , Feminino , Finlândia/epidemiologia , Mortalidade Hospitalar , Hospitais de Distrito/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Classificação Internacional de Doenças , Cuidados Intraoperatórios/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Transfusão de Plaquetas/tendências , Cuidados Pré-Operatórios/estatística & dados numéricos , Adulto Jovem
14.
Life Sci ; 85(19-20): 678-84, 2009 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-19775596

RESUMO

AIMS: Alcohol abuse is associated with increased frequency of infections attributed to ethanol-induced immune suppression. The precise mechanism of immune suppression is however not known. Mast cells (MC) belong to the innate immune system and they have been implicated in the first line of immune defence against bacteria and parasites. Therefore we studied the effects of ethanol and its first metabolite acetaldehyde on mast cell viability, proliferation and apoptosis. MAIN METHODS: Human mast cell line (HMC)-1 cells, mouse bone marrow derived mast cells (mBMMC) and human peripheral blood derived mast cells (HuMC) were used. Effects of ethanol and acetaldehyde on mast cell proliferation were determined by assessing incorporation of [(3)H]thymidine into cellular DNA and by trypan blue exclusion. Apoptosis was assessed by measuring apoptotic nucleosomes and caspase-3, -8 and -9 activities using ELISA and by using Tunel assay. The expression of anti- and proapoptotic proteins Bcl-2 and Bax was analyzed by RT-PCR and western blot, respectively. KEY FINDINGS: Ethanol, but not acetaldehyde inhibited dose-dependently the proliferation and viability HMC-1 and mBMMC cells. The decreased viability was caused by apoptotic cell death of the MC. Significant apoptosis of HMC-1 cells was observed in the presence of 43mM (2.5 per thousand) ethanol. Induction of apoptosis was associated with clearly increased caspase-3 activity and moderately increased caspase-8 and 9 activities. Ethanol also shifted the Bcl-2/Bax balance towards apoptosis. SIGNIFICANCE: The ethanol-induced reduction of MC viability could contribute to immunosuppression associated with ethanol abuse.


Assuntos
Apoptose/efeitos dos fármacos , Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Mastócitos/efeitos dos fármacos , Acetaldeído/farmacologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína X Associada a bcl-2/biossíntese , Proteína X Associada a bcl-2/genética
15.
Chemosphere ; 77(2): 207-13, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19665755

RESUMO

The influence of biodegradable chelating ligands on arsenic and iron uptake by hydroponically grown rice seedlings (Oryza sativa L.) was investigated. Even though the growth solution contained sufficient Fe, the growth of rice seedlings gradually decreased up to 76% with the increase of pH of the solution from 7 to 11. Iron forms insoluble ferric hydroxide complexes at neutral or alkaline pH in oxic condition. Chelating ligands produce soluble 'Fe-ligand complex' which assist Fe uptake in plants. The biodegradable chelating ligand hydroxyiminodisuccinic acid (HIDS) was more efficient then those of ethylenediaminetetraacetic acid (EDTA), ethylenediaminedisuccinic acid (EDDS), and iminodisuccinic acid (IDS) in the increase of Fe uptake and growth of rice seedling. A total of 79+/-20, 87+/-6, 116+/-15, and 63+/-18mg dry biomass of rice seedlings were produced with the addition of 0.5mM of EDDS, EDTA, HIDS, and IDS in the nutrient solution, respectively. The Fe concentrations in rice tissues were 117+/-15, 82+/-8, 167+/-25, and 118+/-22micromolg(-1) dry weights when 0.25mM of EDDS, EDTA, HIDS, and IDS were added to the nutrient solution, respectively. Most of the Fe accumulated in rice tissues was stored in roots after the addition of chelating ligands in the solution. The results indicate that the HIDS would be a potential alternative to environmentally persistent EDTA for the increase of Fe uptake and plant growth. The HIDS also increased As uptake in rice root though its translocation from root to shoot was not augmented. This study reports HIDS for the first time as a promising chelating ligand for the enhancement of Fe bioavailability and As phytoextraction.


Assuntos
Aminoácidos/metabolismo , Arsênio/metabolismo , Quelantes de Ferro/metabolismo , Ferro/metabolismo , Succinatos/metabolismo , Biodegradação Ambiental , Biomassa , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Hidroponia , Ligantes , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
16.
Anim Genet ; 40(5): 616-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19397510

RESUMO

The relationships between behavioural trait data and the genotype of 15 polymorphisms in eight neurotransmitter-related genes were analysed in 77 dogs of the Shiba Inu breed, an indigenous Japanese dog. The data were obtained from a 26-item questionnaire on the dog's behaviour, distributed to the dog's owners, through veterinary hospitals and the Shiba Inu breed magazine. A factor analysis of the questionnaire items extracted eight factors accounting for 66.8% of the variance. An association analysis between these factors and genetic polymorphisms indicated that the polymorphism of c.471T>C in the solute carrier family 1 (neuronal/epithelial high-affinity glutamate transporter) member 2 (SLC1A2) gene was significantly associated with Factor 1, referred to as 'aggression to strangers'. This association remained stable in separate analyses of data from surveys obtained from the hospitals and those obtained from the magazine. The results suggest that the c.471T>C polymorphism is associated with some types of aggressive behaviour in the Shiba Inu. Further studies using other dog breeds are necessary to extend these findings to dogs in general.


Assuntos
Agressão , Comportamento Animal/fisiologia , Cães/genética , Transportador 2 de Aminoácido Excitatório/genética , Polimorfismo Genético , Animais , Cães/fisiologia , Análise Fatorial , Feminino , Genótipo , Japão , Masculino , Especificidade da Espécie , Inquéritos e Questionários
17.
Anim Genet ; 40(2): 217-24, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19170676

RESUMO

The purpose of this study was to attempt to find related variables of the canine genome with behavioural traits of dogs maintained and tested in a guide dog facility which provided a relatively uniform environment. The study involved 81 Labrador Retrievers that were being trained as guide dogs. Each dog was taken on walk-out sessions in which the trainer weekly recorded observations that were related to behavioural traits. The records were subjected to key-word analysis of 14 behaviour-related words. A factor analysis on the appearance rate of the 14 key words or phrases resulted in the extraction of six factors that accounted for 67.4% of the variance. Factor 1, referred to as aggressiveness, was significantly related to the success or failure of the dog in qualifying as a guide dog, and was also related to the variable of litter identification. Factor 2, referred to as distraction, was related to the variable of trainer. Factor 3, activity level, was related to the variable of sex, and was significantly related to the polymorphisms of c.471T>C in the solute carrier family 1 (neuronal/epithelial high affinity glutamate transporter) member 2 gene and c.216G>A in the catechol-O-methyltransferase gene. The involvement of polymorphisms c.471T>C and c.216G>A in behavioural patterns related to activity level is similar to comparable genetic studies in other mammalian species. These results contribute to a greater understanding of the role of these genes in behaviour.


Assuntos
Comportamento Animal , Cegueira/reabilitação , Cães/genética , Cães/psicologia , Genética Comportamental , Animais , Feminino , Genoma , Humanos , Masculino , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único
18.
Sci Total Environ ; 407(4): 1418-25, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19010517

RESUMO

Effects of eutrophication on arsenic speciation were studied in eutrophic Lake Kiba and mesotrophic Lake Biwa, Japan. By combining hydride generation atomic absorption spectrometry with ultraviolet irradiation, inorganic, methyl and ultraviolet-labile fractions of arsenic were determined. In both Lakes, inorganic species (As(V+III)) dominated over other forms of arsenic all the year round. Most of methylarsenic fraction was dimethylarsinic acid (DMAA), and the concentration of monomethylarsonic acid (MMAA) was below the detection limit. Measurements of size-fractioned arsenic concentrations in water column indicate that most of the DMAA was distributed in truly dissolved fraction (<10 kDa), while ultraviolet-labile fractions were distributed in particulate (>0.45 microm) and colloidal (10 kDa-0.45 microm) fractions. Arsenic speciation in eutrophic Lake Kiba fluctuated greatly with season. The ultraviolet-labile fractions were observed with the increase of DMAA from May to October, and they disappeared with the decrease of DMAA in January. In mesotrophic Lake Biwa, the ultraviolet-labile fractions of arsenic were not influenced as much as those in eutrophic Lake Kiba. On the other hand DMAA concentration was higher in Lake Biwa compared to that in Lake Kiba. The results suggest that the biosynthesis of complex organoarsenicals was enhanced by eutrophication, and the arsenic speciation would be influenced by the balance of biological processes in natural waters.


Assuntos
Arsenicais/análise , Eutrofização , Poluentes Químicos da Água/análise , Água Doce , Estações do Ano , Espectrofotometria Atômica
19.
J Fish Dis ; 31(6): 461-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18471102

RESUMO

The minimum inhibitory concentrations (MICs) of 15 chemotherapeutic agents were tested against 146 Lactococcus garvieae strains isolated from 1999 to 2006 in Japan. The agents used included chloramphenicol, ciprofloxacin, erythromycin (EM), enoxacin, fleroxacin, florfenicol, kanamycin, lincomycin (LCM), norfloxacin, oxolinic acid, orbifloxacin, ofloxacin, benzylpenicillin, streptomycin and tetracycline (TC). Of the tested strains, 46 showed high levels of resistance to EM, LCM and TC. Twelve of these strains were detected to be carrying transferable R-plasmids using a conjugation experiment and, using Southern hybridization, were shown to have the same structure as the R-plasmid. The remaining 34 resistant strains had a similar DNA structure to that of the R-plasmid as confirmed by polymerase chain reaction (PCR) using primers designed from sites in the transferable R-plasmid. The EM and TC resistance genes were classified into the ermB and tetS groups using PCR. We also detected gyrA and/or parC mutants that are highly resistant to old and new generation quinolones. This study revealed that transferable R-plasmids encoding EM, LCM and TC are widely distributed and are conserved regardless of the area and/or time of collection.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/genética , Lactococcus/efeitos dos fármacos , Lactococcus/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Girase/genética , DNA Topoisomerase IV/genética , Enterococcus faecalis/genética , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/isolamento & purificação , Lactococcus/metabolismo , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mutação , Fatores R/genética , Alinhamento de Sequência
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