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1.
Nature ; 534(7606): 222-6, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279216

RESUMO

Quantum mechanics can help to solve complex problems in physics and chemistry, provided they can be programmed in a physical device. In adiabatic quantum computing, a system is slowly evolved from the ground state of a simple initial Hamiltonian to a final Hamiltonian that encodes a computational problem. The appeal of this approach lies in the combination of simplicity and generality; in principle, any problem can be encoded. In practice, applications are restricted by limited connectivity, available interactions and noise. A complementary approach is digital quantum computing, which enables the construction of arbitrary interactions and is compatible with error correction, but uses quantum circuit algorithms that are problem-specific. Here we combine the advantages of both approaches by implementing digitized adiabatic quantum computing in a superconducting system. We tomographically probe the system during the digitized evolution and explore the scaling of errors with system size. We then let the full system find the solution to random instances of the one-dimensional Ising problem as well as problem Hamiltonians that involve more complex interactions. This digital quantum simulation of the adiabatic algorithm consists of up to nine qubits and up to 1,000 quantum logic gates. The demonstration of digitized adiabatic quantum computing in the solid state opens a path to synthesizing long-range correlations and solving complex computational problems. When combined with fault-tolerance, our approach becomes a general-purpose algorithm that is scalable.

2.
Phys Rev Lett ; 118(5): 057702, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211704

RESUMO

By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around 2k_{B}T/h≈1 GHz, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a 1/f power law that matches the magnitude of the 1/f noise near 1 Hz. The antisymmetric component displays a 1/T dependence below 100 mK, providing dynamical evidence for a paramagnetic environment. Extrapolating the two-sided spectrum predicts the linewidth and reorganization energy of incoherent resonant tunneling between flux qubit wells.

3.
Phys Rev Lett ; 112(11): 113601, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702367

RESUMO

Continuous quantum measurement is the backbone of various methods in quantum control, quantum metrology, and quantum information. Here, we present a generalized formulation of dispersive measurement of a complex quantum systems. We describe the complex system as an open quantum system that is strongly coupled to a non-Markovian environment, enabling the treatment of a broad variety of natural or engineered complex systems. The system is monitored via a probe resonator coupled to a broadband (Markovian) reservoir. Based on this model, we derive a formalism of stochastic hierarchy equations of motion describing the decoherence dynamics of the system conditioned on the measurement record. Furthermore, we demonstrate a spectroscopy method based on weak quantum measurement to reveal the non-Markovian nature of the environment, which we term weak spectroscopy.

4.
J Chem Phys ; 140(3): 035102, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25669414

RESUMO

Underlying physical principles for the high efficiency of excitation energy transfer in light-harvesting complexes are not fully understood. Notably, the degree of robustness of these systems for transporting energy is not known considering their realistic interactions with vibrational and radiative environments within the surrounding solvent and scaffold proteins. In this work, we employ an efficient technique to estimate energy transfer efficiency of such complex excitonic systems. We observe that the dynamics of the Fenna-Matthews-Olson (FMO) complex leads to optimal and robust energy transport due to a convergence of energy scales among all important internal and external parameters. In particular, we show that the FMO energy transfer efficiency is optimum and stable with respect to important parameters of environmental interactions including reorganization energy λ, bath frequency cutoff γ, temperature T, and bath spatial correlations. We identify the ratio of kBλT/ℏγ⁢g as a single key parameter governing quantum transport efficiency, where g is the average excitonic energy gap.


Assuntos
Proteínas de Bactérias/química , Chlorobium/química , Complexos de Proteínas Captadores de Luz/química , Transferência de Energia , Modelos Moleculares , Temperatura
5.
Reprod Domest Anim ; 49(2): 210-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24237194

RESUMO

A series of five experiments were conducted to explore suitable conditions for storing of goldfish embryos in a chilled state. The factors studied were embryo stage, storage temperature, physiological saline solutions and goldfish artificial coelomic fluid (GFACF) medium, antibiotics (penicillin and streptomycin), antioxidants (vitamin E, vitamin C), buffer (Hepes, Tris) and BSA (bovine serum albumin). First, goldfish embryos at eight developmental stages were incubated in aerated and dechlorinated tap water at 0 °C for 24 h. Result shows that early developmental stages were most sensitive to chilling. Heartbeat-stage goldfish embryos were chilled at 0, 4 or 8 °C for up to 72 h in water, and chilled storage was possible only for up to 18, 24 and 48 h at 0, 4 and 8 °C, respectively, without a decrease in viability. Chilling of goldfish embryos at 8 °C in GFACF medium and Dettlaff's solution instead of water and other physiological saline solutions prolonged their viability (p < 0.01). Nevertheless, viability of chilled embryos in GFACF medium was slightly, but non-significantly, higher than in Dettlaff's solution. Supplementation of the GFACF medium with antibiotics, Hepes or BSA increased the viability of chilled embryos, but the tested vitamin E analogue Trolox, vitamin C or Tris concentration had no effect on embryo viability. The outcome of this series of experiments shows that heartbeat-stage goldfish embryos could be chilled for 60 h in GFACF supplemented with 25 mm Hepes, 100 U/ml penicillin, 10 µg/l streptomycin and 1 g/l BSA in such a way that embryonic development does not proceed, and viability is not lost.


Assuntos
Temperatura Baixa , Embrião não Mamífero/fisiologia , Carpa Dourada/embriologia , Animais , Embrião não Mamífero/citologia , Feminino , Masculino , Fatores de Tempo
6.
J Chem Phys ; 138(20): 204309, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23742477

RESUMO

We explore various design principles for efficient excitation energy transport in complex quantum systems. We investigate energy transfer efficiency in randomly disordered geometries consisting of up to 20 chromophores to explore spatial and spectral properties of small natural/artificial Light-Harvesting Complexes (LHC). We find significant statistical correlations among highly efficient random structures with respect to ground state properties, excitonic energy gaps, multichromophoric spatial connectivity, and path strengths. These correlations can even exist beyond the optimal regime of environment-assisted quantum transport. For random configurations embedded in spatial dimensions of 30 Å or 50 Å, we observe that the transport efficiency saturates to its maximum value if the systems contain around 7 or 14 chromophores, respectively. Remarkably, these optimum values coincide with the number of chlorophylls in the Fenna-Matthews-Olson protein complex and LHC II monomers, respectively, suggesting a potential natural optimization with respect to chromophoric density.


Assuntos
Teoria Quântica , Transferência de Energia
7.
East Asian Arch Psychiatry ; 32(4): 95-99, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36578184

RESUMO

OBJECTIVES: This study aims to examine the psychometric properties of the Persian version of the Structured Clinical Interview for DSM-5 for personality disorders (SCID-5-PD) among patients referred to psychiatric centres in Iran. METHODS: Between March 2017 and June 2019, 287 outpatients and inpatients aged 16 to 75 years who were referred to three psychiatric centres in Tehran, Iran were invited to participate. Patients were interviewed using the Persian version of the SCID-5-PD by two PhD students in clinical psychology who were blinded to patient records. Face validity and content validity of the Persian version of the SCID-5-PD were assessed by five specialists with ≥2 years of clinical experience. The agreement between the diagnoses made with the Persian version of the SCID-5-PD by the two PhD students in clinical psychology and the gold standard diagnoses made with DSM-5 by psychiatrists was determined, as were sensitivity, specificity, and positive and negative likelihood ratios. 109 (43.6%) patients were interviewed again after an interval of 7 to 10 days for inter-rater reliability and test-retest reliability. RESULTS: A total of 250 patients aged 17 to 74 (mean, 32.56) years were included. Face validity and content validity of the Persian version of SCID-5-PD were acceptable. The agreement between the Persian version of SCID-5-PD and DSM-5 (gold standard) was acceptable (kappa >0.4) for the diagnoses of obsessive-compulsive, paranoid, schizotypal, schizoid, histrionic, narcissistic, borderline, and antisocial personality disorders, whereas the agreement was unacceptable (kappa <0.4) for the diagnoses of avoidant and dependent personality disorders. Sensitivity for all diagnoses was high, except for avoidant (0.66) and dependent (0.66) personality disorders. Specificity for all diagnoses was high, except for avoidant personality disorder (0.66). The positive and negative likelihood ratios showed that the SCID-5-PD was accurate for diagnosing all personality disorders, except for schizoid personality disorder. Inter-rater reliability was good for all personality disorders, except for schizotypal personality disorder (0.531). Test-retest reliability was good for all personality disorders. CONCLUSION: The Persian version of the SCID-5-PD can be used to evaluate those who seek psychotherapy for all personality disorders, except for avoidant, dependent, schizoid, and schizotypal personality disorders.


Assuntos
Transtornos da Personalidade , Humanos , Psicometria , Reprodutibilidade dos Testes , Entrevista Psicológica , Irã (Geográfico) , Transtornos da Personalidade/diagnóstico
8.
Phys Rev Lett ; 106(10): 100401, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21469772

RESUMO

The resources required to characterize the dynamics of engineered quantum systems--such as quantum computers and quantum sensors--grow exponentially with system size. Here we adapt techniques from compressive sensing to exponentially reduce the experimental configurations required for quantum process tomography. Our method is applicable to processes that are nearly sparse in a certain basis and can be implemented using only single-body preparations and measurements. We perform efficient, high-fidelity estimation of process matrices of a photonic two-qubit logic gate. The database is obtained under various decoherence strengths. Our technique is both accurate and noise robust, thus removing a key roadblock to the development and scaling of quantum technologies.


Assuntos
Força Compressiva , Teoria Quântica , Fótons
9.
Artigo em Inglês | MEDLINE | ID: mdl-34211573

RESUMO

Cancer is a leading cause of death and a vital health care challenge in the world. Hence, this work was conducted to determine the in vitro anticancer property and also the molecular mechanism of aqueous and organic extracts of Ipomoea purpurea leaves in three human cancer cell lines, including A-549 (human lung cancer), HepG-2 (human liver cancer), MDA-MB-231 (human breast cancer), and MCF-10A (breast normal cell line). In vitro cytotoxic potential of organic extracts, such as hexane, chloroform, ethyl-acetate, methanol, and aqueous extract was examined using a standard (3-(4,5-dimethylthiazole)-2,5-diphenyltetrazolium bromide) MTT method in both monolayer two-dimensional (2D) and spheroids multicellular three-dimensional (3D) cultures. The MTT assay data showed that methanol and chloroform extracts of I. purpurea leaves had the antiproliferative effect on lung and breast cancer cells with IC50 of 53.62 ± 0.07 and 124.5 ± 0.01 µg/mL, respectively. The results of further examinations, such as dual acridine orange/ethidium bromide, Annexin V-FITC/PI, and caspase-3 colorimetric assay, confirmed that methanol and chloroform extracts of I. purpurea as the most potent cytotoxic extracts might contain a variety of phytochemicals, promoting apoptosis in lung and breast cancer cells. The present research findings suggested that methanolic extract of I. purpurea leaves induced S-phase cell cycle arrest and intrinsic pathway of apoptosis in A-549 lung cancer cells. The study further showed that I. purpurea could be a helpful candidate for cancer treatment.

10.
Poult Sci ; 98(11): 5648-5660, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247644

RESUMO

The present study was designed to investigate the effectiveness of dietary fermented soybean meal (FSBM) in comparison with prebiotic (Xylooligosaccharide; XOS) and probiotic (Lactic acid bacteria-based probiotic; LAC) for prevention of Salmonella Typhimurium (ST) infection in young broiler chickens from 1 to 24 d. The in vitro study revealed that soybean meal (SBM) fermentation increased the number of lactic acid bacteria (LAB) and lactic acid content and inhibited the growth of enterobacteria such as coliforms in SBM. A total of 450 day-old Ross 308 broiler chicks were placed in 30 pens (15 birds/pen) and allocated to 5 experimental treatments that consisted an un-supplemented basal diet and not infected (NC) or infected with ST (IC); IC plus 2 g XOS/kg; IC plus 0.2 g LAC/kg; and IC containing a complete replacement of SBM with FSBM. All birds (except NC) were orally administered with 0.5 mL of the ST solution (1 × 106 CFU/mL) at d 3 post-hatch. The ST challenge decreased body weight gain and feed intake (P < 0.05). The impairment of feed conversion ratio was alleviated by the addition of XOS, LAC, and FSBM in broiler diets compared with IC birds (P < 0.05). The ST infection reduced duodenum and jejunum villus height and increased Salmonella colonization throughout the gut as well as internal organ invasion compared with NC birds (P < 0.05). However, ST-infected broilers fed the XOS, LAC, and FSBM-containing diets showed a significant decrease in gut Salmonella colonization, and internal organ invasion, an increase in LAB counts, and improvement in intestinal mucosa morphology (P < 0.05). The tested feed additives or FSBM reduced heterophil to lymphocyte ratio compared with the IC group (P < 0.05). The results suggest that XOS, LAC, and FSBM improve growth performance, lower Salmonella colonization, and improve intestinal characteristics and immune response in ST-challenged broiler chicks. Therefore, fermented feeds due to having functional ingredients can be considered as an effective strategy to lessen the colonization of gut pathogens in broiler chickens.


Assuntos
Galinhas , Glycine max/química , Doenças das Aves Domésticas/prevenção & controle , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Salmonelose Animal/prevenção & controle , Ração Animal/análise , Animais , Dieta/veterinária , Fermentação , Glucuronatos/administração & dosagem , Lactobacillales/química , Masculino , Oligossacarídeos/administração & dosagem , Doenças das Aves Domésticas/microbiologia , Distribuição Aleatória , Salmonelose Animal/microbiologia , Salmonella typhimurium/fisiologia
11.
Poult Sci ; 98(10): 4909-4918, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31065719

RESUMO

A study was conducted to determine the impacts of dietary inclusion of fish waste silage (FWS) substituting soybean meal (SBM) on the performance, gut microflora, cecal short-chain fatty acid, apparent ileal digestibility (AID), digestive enzyme activity, and excreta noxious gas emission in broiler chickens. A total of 720-day-old male broilers (Cobb 500) were randomly allocated to 3 dietary treatments with 12 replicates each accommodating 20 birds for 42 d. Birds received diets as follows: a corn-SBM-based diet (CON) and 2 diets that replaced SBM with FWS at 60 g/kg (FWS60) and 120 g/kg (FWS120). During the entire period, replacing SBM with FWS60 and FWS120 increased body weight gain and decreased feed conversion ratio (P < 0.05). The lowest pH values in the crop, proventriculus, duodenum, ileum, and ceca were observed in birds fed diets containing FWS60 and FWS120 (P < 0.05). Likewise, birds fed FWS60 and FWS120 had lower numbers of coliform and E. coli and higher Bifidobacterium and Lactobacillus count in the ceca than those fed CON (P < 0.05). Feeding FWS60 and FWS120 diets increased cecal butyrate and lactic acid contents (P < 0.05). Birds fed FWS120 diets had greater intestinal amylase and protease activity than birds fed CON (P < 0.05); however, no significant differences were recorded between the treatment groups for digestive enzymes activity in the pancreas. The use of both levels of FWS in broiler diet increased AID of crude protein and ether extract (P < 0.05). The lowest excreta ammonia concentration was recorded in birds fed FWS120 diet (P < 0.05). In conclusion, the inclusion of FWS in broiler diets could improve the performance by enhancing gut function, derived from the improved digestive enzyme activity and nutrient digestibility, as well as by elevating the population of beneficial bacteria and short-chain fatty acid contents. Therefore, the biological silage can be considered as a promising option for recycling and recovery of fish wastes and effectively be used in broiler diets.


Assuntos
Galinhas/fisiologia , Digestão/efeitos dos fármacos , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Microbioma Gastrointestinal/efeitos dos fármacos , Silagem/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Ceco/microbiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Gases/análise , Masculino , Nutrientes/fisiologia , Glycine max/química
12.
Poult Sci ; 98(12): 6797-6807, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31347672

RESUMO

This study investigated the effects of fermented soybean meal (FSBM) with or without mannan-oligosaccharide (MOS) prebiotic on growth performance, digestive functions, and hepatic IGF-1 gene expression of broiler chicken. A total of 480 day-old male broiler chickens were fed with 4 experimental diets for 6 wk. Experimental diets included corn-soybean meal diet (CON); corn-soybean meal diet + MOS prebiotic [0.2%, ActiveMOS; Biorigin, Brazile]; corn-FSBM diet [soybean meal (SBM) was totally replaced by FSBM]; and corn-FSBM + MOS prebiotic (MIX). Replacing dietary SBM with FSBM with or without MOS improved body weight gain and feed efficiency for the total grow-out period. However, the addition of MOS to the FSBM diet exhibited a greater body weight gain than other experimental diets. Villus height and villus height to crypt depth of the duodenum and jejunum were increased by feeding FSBM, MOS, and MIX diets. The ileal crude protein and energy digestibilities, as well as the activities of intestinal amylase and protease, and pancreatic protease, were improved by replacing SBM with FSBM, with or without MOS. The concentration of plasma 3-methylhistidine was reduced by FSBM and MOS, and synergistically by their combination. The MOS and FSBM diets upregulated the hepatic IGF-1 gene expression. However, there was an evident synergistic effect of FSBM supplemented with MOS in the upregulation of the hepatic IGF-1 gene expression. The outcomes of the current study indicate the FSBM and MOS had the potential to improve growth performance, hepatic IGF-1 expression, and intestinal morphology of broilers. Overall, the fermented products could be considered as functional feed that exhibits probiotic effects and the synergistic effects of prebiotics added to the fermented feeds may further improve the growth performance and gut health and functionality in broiler chicken.


Assuntos
Galinhas/fisiologia , Digestão/fisiologia , Expressão Gênica , Glycine max/química , Fígado/metabolismo , Mananas/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão/efeitos dos fármacos , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Mananas/administração & dosagem , Oligossacarídeos/administração & dosagem , Oligossacarídeos/metabolismo , Distribuição Aleatória
13.
Poult Sci ; 97(6): 2113-2122, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29554364

RESUMO

This study was conducted to investigate and compare the effect of dietary probiotic mixture (PM) and organic acid (OA) mixture with fermented soybean meal (FSBM) on performance, crop, and ceca microbiota, small intestine morphology, and serum lipid profile in Japanese quails. A total of 800 day-old Japanese quails was randomly allotted to 5 treatments with 8 replicate pens of 20 birds each, for 35 days. The experimental diets consisted of a control corn-soybean meal diet and 4 test diets: 1) control diet + 0.1% PM; 2) control diet + 0.2% OA mixture; 3) control diet + the combination of both PM and OA; and 4) an additives-free diet in which the soybean meal in the control diet was replaced with FSBM. The results indicated that in starter and the entire rearing periods, FSBM, PM, and PM+OA diets had significantly lower FCR compared to control or OA diets (P < 0.05). Birds in the FSBM group gained higher weight than control and OA birds (P < 0.05; 1 to 35 d). At d 21 and 35, birds fed the control diet showed significantly lower numbers of lactic acid bacteria in the crop, while coliforms were higher in the cecal content compared to the other diets (P < 0.05). At d 21, the villus height and villus height to crypt depth ratio in the duodenum and jejunum of birds fed PM, PM+OA, and FSBM diets were greater than in other treatments (P < 0.05). The serum concentrations of cholesterol and low-density lipoprotein cholesterol of birds fed PM, PM+OA, and FSBM diets were significantly lower than birds in control and AO groups (P < 0.05). The results obtained herein suggest that FSBM exhibits probiotic properties and, when used in substitution of SBM in Japanese quail diet, can improve growth performance, balance of desirable gastrointestinal microbiota in crop and ceca, small intestinal morphology, and serum lipid profile-likewise, a probiotic supplement.


Assuntos
Coturnix/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Glycine max/química , Lipídeos/sangue , Probióticos/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Fermentação , Trato Gastrointestinal/anatomia & histologia , Masculino , Distribuição Aleatória , Glycine max/metabolismo
14.
J Hazard Mater ; 148(1-2): 446-52, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17418486

RESUMO

A flow injection analysis (FIA) system incorporation a microcolumn of immobilized oxine on surfactant-coated alumina had been devised for performing rapid thallium enrichment/matrix removal in flame atomic absorption spectrometry (FAA). The preconcentration is based on the deposition of thallium(I) on microcolumn and subsequent elution with 500 microl of sodium thiosulfate (1 moll(-1)). In the presence of EDTA, only Tl(I) was retained on the microcolumn. Total thallium was determined after reduction of Tl(III) to Tl(I) by hydroxyl amine hydrochloride. A sample volume of 25 ml resulted in a preconcentration factor of 77. Precision at 30 microgl(-1) was 2.6% RSD (n=10). With 25 ml sampling volume a detection limit of 2.5 microgl(-1) was determined. The effect of potential interfering ions on the determination was studied. The method was applied for the determination of thallium in water, waste water, hair, nail, coal, and standard reference alloys. The accuracy was assessed through recovery experiment, independent analysis by Furnace-AAS, and analysis of certified reference alloys.


Assuntos
Oxiquinolina , Espectrofotometria Atômica/métodos , Tálio/análise , Análise de Injeção de Fluxo , Microquímica/instrumentação , Sistemas On-Line , Reprodutibilidade dos Testes
15.
Appl Radiat Isot ; 115: 289-294, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27451113

RESUMO

In this research gas sealed Multi-Wire Proportional Counter (MWPC) including blades between anode wires and beta particles of (90)Sr with 196keV mean energy were considered. Ten different gases such as Noble gases mixtures with methane and several other pure gases were studied. In this type of detector, by using Garfield and Maxwell codes and for each of the gases, variation of different parameters such as first Townsend, electron attachment coefficients with variable electric field and their effects on pulse height or collected charge and in turn on Signal to Noise Ratio (SNR) were studied. Also the effect of anode voltage and its diameter and the pressure of gas on the pulse height were studied. Results show that Garfield and Maxwell codes can be used to study and improve the design of other gaseous detectors.

17.
Toxicology ; 149(2-3): 109-14, 2000 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-10967408

RESUMO

In this work we have attempted to characterize the programmed cell death (apoptosis) in alveolar macrophages exposed to various concentrations of lead nitrate. It was found that after 3 h of exposure a significant increase in superoxide anion production was observed, i.e. the number of trypan blue - exculding cells, was unchanged (< or = 95%) with any dose of lead employed. Agarose gel electrophoresis and diphenylamin reaction analysis revealed the occurrence of internucleosomal DNA fragmentation evaluated using cytological analysis by fluorescence dyes, suggesting that lead nitrate at low concentrations and short periods of exposure leads macrophages into apoptosis. However, time course studies showed that beyond 3 h, toxicity occurs, which could be attenuated by phosphodiesterase inhibitors, such as caffeine, suggesting a possible mechanism involving cAMP.


Assuntos
Apoptose/efeitos dos fármacos , Chumbo/farmacologia , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nitratos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , DNA/efeitos dos fármacos , DNA/genética , DNA/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Pulmão/citologia , Pulmão/metabolismo , Macrófagos Alveolares/citologia , Macrófagos Alveolares/metabolismo , Ratos , Superóxidos/metabolismo , Fatores de Tempo
18.
Br J Radiol ; 75(896): 689-91, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12153944

RESUMO

A case of a pseudoaneurysm arising from the inferior epigastric artery in a patient presenting with a rectus sheath haematoma is reported. The pseudoaneurysm was successfully treated by percutaneous injection of human thrombin.


Assuntos
Falso Aneurisma/diagnóstico por imagem , Artérias Epigástricas/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Idoso , Falso Aneurisma/tratamento farmacológico , Feminino , Hemostáticos/administração & dosagem , Humanos , Injeções , Trombina/administração & dosagem
19.
Talanta ; 46(6): 1379-86, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18967267

RESUMO

A highly sensitive and selective method is described for the determination of trace amounts of nitrite based on its effect on the oxidation of carminic acid with bromate. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of carminic acid at 490 nm after 3 min of mixing the reagents. The optimum reaction conditions were 1.8x10(-1) mol l(-1) H(2)SO(4), 3.8x10(-3) mol l(-1) KBrO(3), and 1.2x10(-4) mol l(-1) carminic acid at 30 degrees C. By using the recommended procedure, the calibration graph was linear from 0.2 to 14 ng ml(-1) of nitrite; the detection limit was 0.04 ng ml(-1); the R.S.D. for six replicate determinations of 6 ng ml(-1) was 1.7%. The method is mostly free from interference, especially from large amounts of nitrate and ammonium ions. The proposed method was applied to the determination of nitrite in rain and river water.

20.
J Pharm Biomed Anal ; 18(4-5): 877-81, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9919991

RESUMO

A novel spectrophotometric method is described for the determination of epinephrine (EP) and norepinephrine (NE). The method is based on the development of a red colour with sodium bismuthate, as a sensitive chromogenic reagent, in aqueous medium at pH 3. Oxidation of these catecholamines produces aminochrome derivatives which can be measured spectrophotometrically at 486.0 nm. Calibration graphs are linear in the range 4.8-800 (micromol l(-1)) for epinephrine bitartarate and 4.8-600 (micromol l(-1)) for norepinephrine bitartarate with detection limits of 0.26 (micromol l(-1)) and 2.46 (micromol l(-1)) for epinephrine and norepinephrine bitartarate salts, respectively. The method has successfully been applied to determination of these catecholamines in pharmaceutical preparations.


Assuntos
Antioxidantes , Bismuto , Catecolaminas/análise , Compostos Cromogênicos , Espectrofotometria Atômica/métodos , Espectrofotometria Ultravioleta/métodos , Epinefrina/análise , Concentração de Íons de Hidrogênio , Norepinefrina/análise , Temperatura
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