Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Mais filtros

Base de dados
Intervalo de ano de publicação
Biosens Bioelectron ; 24(11): 3299-305, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19450964


A semi-automated bacterial spore detection system (BSDS) was developed to detect biological threat agents (e.g., Bacillus anthracis) on-site. The system comprised an aerosol sampler, micro-fluidic chip-A (for spore germination and cell lysis), micro-fluidic chip-B (for extraction and detection of genomic DNA) and an analyzer. An aerosol with bacterial spores was first collected in the collection chamber of chip-A with a velocity of 300 l/min, and the chip-A was taken off from the aerosol sampler and loaded into the analyzer. Reagents packaged in the chip-A were sequentially applied into the chamber. The genomic DNA extract from spore lyzate was manually transferred from chip-A to chip-B and loaded into the analyzer. Genomic DNA in chip-B was first trapped on a glass bead column, washed with various reagents, and eluted to the detection chamber by sequential auto-dispensing. Isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) with fluorescent measurement was adopted to amplify and detect target DNA. Bacillus subtilis was the stimulant of biological warfare agent in this experiment. Pretreatment conditions were optimized by examining bacterial target DNA recovery in the respective steps (aerosol collection, spore germination, cell lysis, and DNA extraction), by an off-chip experiment using a real-time polymerase chain reaction quantification method. Without the germination step, B. subtilis spores did not demonstrate amplification of target DNA. The detection of 10(4) spores was achieved within 2h throughout the micro-fluidic process.

Aerossóis/análise , Bacillus anthracis/genética , Bacillus anthracis/isolamento & purificação , Técnicas Biossensoriais/instrumentação , DNA Bacteriano/análise , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Microbiologia do Ar , Algoritmos , DNA Bacteriano/genética , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Técnicas de Amplificação de Ácido Nucleico/métodos , Esporos Bacterianos/genética , Esporos Bacterianos/isolamento & purificação
Birth Defects Res C Embryo Today ; 81(1): 41-50, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17539012


In this treatise we will examine complexities in the development and function of cells of the musculoskeletal system. Specifically, the role of chondrocytes and their ontogeny and osteoblasts and their ontogeny will be discussed as they regulate cartilage and bone formation. This background information will provide the foundation for evaluating the effects of environmental toxicants on skeletal development. A number of agents such as heavy metals (i.e. lead) and polycyclic aromatic hydrocarbons (i.e. pesticides and cigarette smoke) interact with cells of the skeletal system and adversely affect development. These agents have not been of major research interest, nevertheless, given changes in the environmental profile of the United States and other developed countries, it is important that we understand their effects in bone and cartilage. Research in this area will identify strategies that may be used to help prevent musculoskeletal diseases due to toxicant exposure.

Desenvolvimento Ósseo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Animais , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Humanos , Intoxicação por Chumbo/complicações , Intoxicação por Chumbo/patologia , Metais Pesados/toxicidade , Osteoartrite/etiologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo
Steroids ; 68(7-8): 693-703, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12957675


A method is described for the preparation of two types of multi-labeled 6 beta-hydroxycortisol containing either five deuterium atoms at C-19 methyl and C-1 methylene or four 13C atoms at C-1, C-2, C-4, and C-19 in addition to the five deuterium atoms for use as analytical internal standards for gas chromatography-mass spectrometry (GC-MS). BMD derivatives of [1,1,19,19,19-2H(5)]cortisone and [1,2,4,19-13C(4),1,1,19,19,19-2H(5)]cortisone (cortisone-2H(5)-BMD and cortisone-13C(4),2H(5)-BMD) were first synthesized via indan synthon method starting from optical active 11-oxoindanylpropionic acid and labeled isopropenyl anion ([1,1,3,3,3-2H(5)]- or [1,3-13C(2),1,1,3,3,3-2H(5)]isopropenyl anion). The labeled isopropenyl anion was prepared from commercially available [1,1,1,3,3,3-2H(6)]- or [1,3-13C(2),1,1,1,3,3,3-2H(6)]acetone. Ultraviolet (UV) irradiated autoxidation at C-6 position of 3-ethyl-3,5-dienol ether derivatives of the labeled cortisone-BMDs gave 6 beta-hydroxy-[1,1,19,19,19-2H(5)]cortisone-BMD and 6 beta-hydroxy-[1,2,4,19-13C(4),1,1,19,19,19-2H(5)]cortisone-BMD, respectively, as a mixture of 6 beta- and 6 alpha-epimers in a ratio of 4:1. Separation of 6 beta- and 6 alpha-epimers by thin-layer chromatography (TLC) and subsequent hydrolysis of the BMD group at C-17 gave pure labeled 6 beta-hydroxycortisone. After protecting the keto group at C-3 of the labeled 6 beta-hydroxycortisone-BMD as semicarbazone, reduction of 11-keto group with NaBH(4) and subsequent removal of the C-3 and C-17 protecting groups gave 6beta-hydroxy-[1,1,19,19,19-2H(5)]cortisol (6 beta-hydroxycortisol-2H(5)) and 6 beta-hydroxy-[1,2,4,19-13C(4),1,1,19,19,19-2H(5)]cortisol (6 beta-hydroxycortisol-13C(4),2H(5)), respectively, as a mixture of 6 beta- and 6 alpha-epimers (6 beta:6 alpha=4.4:1). The isotopic compositions of 6 beta-hydroxycortisol-2H(5) and 6 beta-hydroxycortisol-13C(4),2H(5) were 90.9 and 92.1 at.%, respectively. Furthermore, 6 beta-hydroxy-[1 alpha,16,16,17 alpha-2H(4)]testosterone was synthesized by the UV irradiated autoxidation at C-6 position of 3-ethyl-3,5-dienol ether derivative of deuterium-labeled testosterone ([1 alpha,16,16,17 alpha-2H(4)]testosterone) obtained by using catalytic deuteration and hydrogen-deuterium exchange reactions.

Cortisona/síntese química , Hidrocortisona/análogos & derivados , Hidrocortisona/síntese química , Hidroxitestosteronas/síntese química , Marcação por Isótopo/métodos , Isótopos de Carbono , Cortisona/análogos & derivados , Deutério , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxirredução/efeitos da radiação , Raios Ultravioleta