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1.
Tob Control ; 17 Suppl 1: i10-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18768454

RESUMO

Of the chemicals identified to date in mainstream cigarette smoke with known toxicological properties, the volatile organic compounds (VOCs) are considered the most hazardous group owing to their high abundance and toxicity. In this research we evaluate a recently introduced line of cigarettes that contain charcoal in their filters. The amount of charcoal in these filters ranged from 45 mg to 180 mg and were either dispersed among the filter material or contained in a small cavity in the filter segment. Charcoal has long been used for removing VOCs from both water and air. Our findings indicate that these cigarettes reduce machine generated mainstream smoke deliveries of a wide range of VOCs compared to a similar, non-charcoal filtered, cigarette. However, this reduction is dependent not only on the amount of charcoal present but also on the volume of smoke being drawn through the filter. While a brand with 45 mg charcoal reduces VOC delivery under ISO smoking conditions, charcoal saturation and breakthrough occur under more intense smoking conditions. Breakthrough is minimised for brands with the most charcoal. Overall, the brands with the most charcoal are effective at reducing VOC deliveries under even intense smoking conditions.


Assuntos
Carvão Vegetal/química , Filtração/instrumentação , Nicotiana/química , Fumaça/análise , Compostos Orgânicos Voláteis/análise , Qualidade de Produtos para o Consumidor , Teste de Materiais/métodos , Nicotina/análise , Fumar
2.
Proc Natl Acad Sci U S A ; 100(24): 14281-6, 2003 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-14623959

RESUMO

To eliminate apicomplexan parasites, inhibitory compounds must cross host cell, parasitophorous vacuole, and parasite membranes and cyst walls, making delivery challenging. Here, we show that short oligomers of arginine enter Toxoplasma gondii tachyzoites and encysted bradyzoites. Triclosan, which inhibits enoyl-ACP reductase (ENR), conjugated to arginine oligomers enters extracellular tachyzoites, host cells, tachyzoites inside parasitophorous vacuoles within host cells, extracellular bradyzoites, and bradyzoites within cysts. We identify, clone, and sequence T. gondii enr and produce and characterize enzymatically active, recombinant ENR. This enzyme has the requisite amino acids to bind triclosan. Triclosan released after conjugation to octaarginine via a readily hydrolyzable ester linkage inhibits ENR activity, tachyzoites in vitro, and tachyzoites in mice. Delivery of an inhibitor to a microorganism via conjugation to octaarginine provides an approach to transporting antimicrobials and other small molecules to sequestered parasites, a model system to characterize transport across multiple membrane barriers and structures, a widely applicable paradigm for treatment of active and encysted apicomplexan and other infections, and a generic proof of principle for a mechanism of medicine delivery.


Assuntos
Coccidiostáticos/administração & dosagem , Toxoplasma/efeitos dos fármacos , Sequência de Aminoácidos , Animais , DNA de Protozoário/genética , Sistemas de Liberação de Medicamentos , Enoil-(Proteína de Transporte de Acila) Redutase (NADH) , Inibidores Enzimáticos/farmacologia , Feminino , Genes de Protozoários , Camundongos , Dados de Sequência Molecular , Oxirredutases/antagonistas & inibidores , Oxirredutases/genética , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Homologia de Sequência de Aminoácidos , Toxoplasma/enzimologia , Toxoplasma/genética , Toxoplasmose/tratamento farmacológico , Toxoplasmose/parasitologia , Triclosan/análogos & derivados , Triclosan/farmacologia
3.
Br J Oral Maxillofac Surg ; 25(1): 34-44, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2948542

RESUMO

Cefotetan is a new cephamycin antibiotic characterised by excellent B-lactamase stability and anti-anaerobe activity, coupled with a long half life of 3-4 h which permits twice daily dosage. A clinical trial of cefotetan in the treatment of severe oro-facial infections is presented, together with a detailed analysis of the causative organisms and their sensitivities to eight antibiotics. 50/50 patients achieved clinical cure with a treatment regime comprising cefotetan therapy and incision and drainage, with patients being transferred to oral cephradine for the final phase of therapy. Side effects were minimal and there were no instances of relapse. Significant resistance among alpha-haemolytic streptococci and bacteroides organisms to penicillin was observed. The streptococci were resistant due to mechanisms other than beta-lactamase production. In the light of these findings and the reports of other workers it is suggested that penicillin V may no longer be the most appropriate drug for endocarditis prophylaxis, despite the most recent recommendations of the American Heart Association. Furthermore, if penicillin V is used for this purpose, a penicillin free interval of 6-8 weeks may be inadequate before this drug is used. Cefotetan is not suitable for prophylaxis against endocarditis.


Assuntos
Antibacterianos/uso terapêutico , Cefamicinas/uso terapêutico , Infecção Focal Dentária/tratamento farmacológico , Doença Aguda , Antibacterianos/farmacologia , Bacteroidaceae/efeitos dos fármacos , Bacteroidaceae/isolamento & purificação , Cefotetan , Cefamicinas/farmacologia , Ensaios Clínicos como Assunto , Eritromicina/farmacologia , Eritromicina/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Penicilinas/uso terapêutico , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus/efeitos dos fármacos , Streptococcus/isolamento & purificação
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