Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Int J Cosmet Sci ; 44(6): 672-684, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35924329

RESUMO

OBJECTIVE: Scalp hair is among the most exposed parts of the human body, yet the impact of visible and UV light on hair lipids, an important structural component of hair, is poorly researched. We have used lipidomics, a broad-based approach to measure lipids in samples, which has hitherto not been applied to UV-exposed hair in the published literature, and could allow for a wider understanding of how UV light impacts on specific hair lipids. METHODS: Mixed blonde Caucasian hair switches were divided into two groups of five, with half of the hair switches exposed to UV and visible light mimicking normal daytime exposure and half left unexposed. LC-MS lipidomics was used to profile the lipids in the hair samples. RESULTS: A total of 791 lipids and 32 lipid classes with tentative identifications were detected in the hair samples. Nineteen lipid classes and 397 lipids differed between UV-treated and non-treated hair. The main lipid classes that differed were vitamin A fatty acid esters, sterol esters, several ceramides, mono-, di- and triglycerides, phosphatidylethanolamines (all decreased in UV-exposed hair) and bismonoacylglycerolphosphates, acylcarnitines and acylglycines (all increased in UV-exposed hair). Most detected lipids were decreased in UV-exposed hair, supporting earlier work that has found that UV exposure causes oxidation of lipids which would result in a decrease in most lipid classes. CONCLUSION: Light exposure to hair has a widespread impact on the hair lipidome. This study also adds to the emerging literature on the hair lipidome, broadening the range of lipid classes reported in hair.


OBJECTIF: Le cuir chevelu est l'une des parties les plus exposées de l'organisme. Cependant, l'impact de la lumière visible et des UV sur les lipides capillaires, un composant structurel important des cheveux, reste mal étudié. Nous avons utilisé la lipidomique, une approche large pour mesurer les lipides présents dans les échantillons de cheveux, qui n'a jusqu'ici pas été appliquée aux cheveux exposés aux UV dans la littérature publiée. Cette approche pourrait permettre de mieux comprendre l'impact de la lumière UV sur des lipides spécifiques des cheveux. MÉTHODES: Les mèches de cheveux caucasiens blonds mélangés ont été divisées en deux groupes de cinq, la moitié des mèches de cheveux étant exposées aux UV et à une lumière visible imitant l'exposition diurne normale tandis que l'autre moitié est restée non exposée. Le profil lipidique des échantillons de cheveux a été établi grâce à la lipidomique de la LC-MS. RÉSULTATS: Au total, 791 lipides et 32 classes de lipides avec des identifications provisoires ont été détectés dans les échantillons de cheveux. Entre les cheveux traités par UV et les cheveux non traités, dix-neuf classes de lipides et 397 lipides se sont avérés différents. Les principales classes de lipides qui différaient étaient les esters d'acides gras de la vitamine A, les esters de stérols, plusieurs céramides, les monoglycérides, diglycérides et triglycérides, les phosphatidyléthanolamines (tous diminués dans les cheveux exposés aux UV) et les bismonoacylglycérolphosphates, acylcarnitines et acylglycines (tous augmentés dans les cheveux exposés aux UV). La plupart des lipides détectés dans les cheveux exposés aux UV n'étaient présents qu'à taux réduit, soit un résultat cohérent avec une étude antérieure ayant montré que l'exposition aux UV provoque l'oxydation des lipides, ce qui entraînerait une diminution de la plupart des classes de lipides. CONCLUSION: L'exposition des cheveux à la lumière entraîne un impact généralisé sur leur lipidome. Cette étude vient également compléter la littérature émergente sur le lipidome capillaire, élargissant ainsi la gamme de classes lipidiques rapportées dans les cheveux.


Assuntos
Lipidômica , Raios Ultravioleta , Humanos , Lipídeos/química , Cromatografia Líquida , Cabelo
2.
Methods Mol Biol ; 2452: 131-146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35554905

RESUMO

A number of viral quantification methods are used to measure the concentration of infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While the traditional plaque-based assay allows for direct enumeration of replication competent lytic virions and remains the gold standard for the quantification of infectious virus, the 50% tissue culture infectious dose (TCID50) endpoint dilution assay allows for a more rapid, large-scale analysis of experimental samples. In this chapter, we describe a well-established TCID50 assay protocol to measure the SARS-CoV-2 infectious titer in viral stocks, in vitro cell or organoid models, and animal tissue. We also present alternative assays for scoring the cytopathic effect of SARS-CoV-2 in cell culture and comparable methods to calculate the 50% endpoint by serial dilution.


Assuntos
COVID-19 , Doenças Transmissíveis , Animais , Bioensaio/métodos , Efeito Citopatogênico Viral , SARS-CoV-2
3.
Commun Biol ; 5(1): 242, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35304580

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has incited a global health crisis. Currently, there are limited therapeutic options for the prevention and treatment of SARS-CoV-2 infections. We evaluated the antiviral activity of sulforaphane (SFN), the principal biologically active phytochemical derived from glucoraphanin, the naturally occurring precursor present in high concentrations in cruciferous vegetables. SFN inhibited in vitro replication of six strains of SARS-CoV-2, including Delta and Omicron, as well as that of the seasonal coronavirus HCoV-OC43. Further, SFN and remdesivir interacted synergistically to inhibit coronavirus infection in vitro. Prophylactic administration of SFN to K18-hACE2 mice prior to intranasal SARS-CoV-2 infection significantly decreased the viral load in the lungs and upper respiratory tract and reduced lung injury and pulmonary pathology compared to untreated infected mice. SFN treatment diminished immune cell activation in the lungs, including significantly lower recruitment of myeloid cells and a reduction in T cell activation and cytokine production. Our results suggest that SFN should be explored as a potential agent for the prevention or treatment of coronavirus infections.


Assuntos
Antivirais/uso terapêutico , Resfriado Comum/tratamento farmacológico , Infecções por Coronavirus/tratamento farmacológico , Coronavirus Humano OC43 , Isotiocianatos/uso terapêutico , SARS-CoV-2 , Sulfóxidos/uso terapêutico , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Alanina/análogos & derivados , Alanina/uso terapêutico , Animais , Células CACO-2 , Chlorocebus aethiops , Resfriado Comum/virologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Citocinas/imunologia , Sinergismo Farmacológico , Humanos , Pulmão/imunologia , Pulmão/virologia , Macrófagos Alveolares/imunologia , Masculino , Camundongos Transgênicos , Baço/imunologia , Linfócitos T/imunologia , Células Vero , Carga Viral , Tratamento Farmacológico da COVID-19
4.
J Cosmet Dermatol ; 21(5): 2246-2254, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34416057

RESUMO

BACKGROUND: Damage to hair by UV is relevant to most people, and for many, it is a major source of hair damage. Prevention of UV damage is of high interest to cosmetic companies. OBJECTIVES: Describe UV damage mechanisms and link these mechanisms to measurable changes in hair protein composition and color changes resulting from breakdown of yellow-colored kynurenines. Test the power of botanical antioxidants, specifically Camellia sinensis (tea) extracts to prevent this protein damage and color change. Link specific phytochemistry of extract samples to hair performance. METHODS: Camellia sinensis (tea) extracts were analyzed by LC-MS to identify the key composition chemistries. ORAC (Oxygen Radical Antioxidant Capacity) was used to measure ability of the extract to react with a peroxyl radical via a hydrogen abstraction mechanism. Hair protein structural damage was measured by quantification of a biomarker peptide that is specific to UV-induced damage and hair color changes were measured with a spectrophotometer. RESULTS: Levels of key phytochemistry in the extracts, specifically the catechins, correlated with prevention of UV-induced protein damage and prevention of color changes due to kynurenine breakdown. Extracts with higher phytochemistry levels also had higher ORAC scores indicating that they were more effective antioxidants. CONCLUSIONS: Camellia sinensis (tea) extracts can be used as effective protective treatments for hair protection but this efficacy is linked to extract concentrations of key chemistries (catechins).


Assuntos
Camellia sinensis , Catequina , Antioxidantes/farmacologia , Camellia sinensis/química , Catequina/química , Cabelo/metabolismo , Humanos , Extratos Vegetais/farmacologia , Chá/química
5.
Int J Cosmet Sci ; 44(1): 82-90, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34860415

RESUMO

OBJECTIVE: Human hair is regularly subjected to chemical and physical insults, such as heat, UV-irradiation and alkaline hair care products. These insults result in molecular modifications at the hair protein level that underpin mechanical and sensory property changes in the fibres. These changes can manifest itself in reduced hair quality and performance attributes observable to the consumer. In this work, changes in protein modification as a result of heat and alkaline treatments are determined. METHODS: Redox proteomic profiling using high-resolution mass spectrometry was applied to map and evaluate amino acid residue modifications in human hair exposed to a combination of thermal treatments and alkali exposure with the aim to understand the underlying chemical processes. RESULTS: Our results show that an increase in redox-related modifications is associated with exposure to higher levels of hydrothermal and alkaline insult. Post-translational modification profiling at the protein primary structural level delivered some further insights into the site-specificity of these modifications, with a clear increase in the number of cysteic acid modifications noticed in samples subjected to more extreme insults. CONCLUSION: Pinpointing modification sides within proteins and the hair shaft proteome can be used as a basis for employing mitigation or repair strategies of hair protein damage caused by environmental or hair treatment-related insults.


OBJECTIF: Les cheveux humains sont sujet à de nombreuses agressions physiques et chimiques telles que la chaleur, les radiations ultra-violettes et les produits alcalins d'entretien des cheveux. Ces agressions entrainent des modifications moléculaires dans les protéines constituant les cheveux et elles conduisent aussi à des changements mécaniques et sensoriels des fibres capillaires. Les manifestations possibles de ces transformations sont une baisse, visible pour le consommateur, de la qualité et des indicateurs de performance des cheveux. Lors de cette étude, nous mettons en évidence les changements au niveau protéique liés à la chaleur et aux traitements alcalins. MÉTHODES: Les méthodes de profilage d'oxydoréduction protéomique utilisant des spectromètres de masses à haute résolution ont été utilisées afin d'évaluer les modifications des amino-acides dans les cheveux humains après exposition à plusieurs combinaisons de traitements thermiques et alcalins dans le but de comprendre les processus chimiques impliqués. RÉSULTATS: Nos résultats montrent que l'augmentation des modifications d'oxydoréduction est associée à des niveaux élevés d'exposition aux traitements thermiques et/ou alcalins. Le profilage des modifications post-translationnelles des structures primaires des protéines ont permis de mieux comprendre les spécificités de ces modifications ; notamment une augmentation nette du nombre des modifications des acides cystéiques liée aux traitements les plus agressifs. CONCLUSION: Ce travail d'identification des modifications engendrées par les agressions liées aux traitements capillaires ou environnementales peut désormais servir de base pour évaluer et mettre en place des techniques de réduction des risques, protection et de réparation des protéines des cheveux.


Assuntos
Proteínas , Proteômica , Cabelo/química , Humanos , Espectrometria de Massas , Oxirredução , Proteínas/análise , Proteômica/métodos
6.
bioRxiv ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33791708

RESUMO

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), has incited a global health crisis. Currently, there are no orally available medications for prophylaxis for those exposed to SARS-CoV-2 and limited therapeutic options for those who develop COVID-19. We evaluated the antiviral activity of sulforaphane (SFN), a naturally occurring, orally available, well-tolerated, nutritional supplement present in high concentrations in cruciferous vegetables with limited side effects. SFN inhibited in vitro replication of four strains of SARS-CoV-2 as well as that of the seasonal coronavirus HCoV-OC43. Further, SFN and remdesivir interacted synergistically to inhibit coronavirus infection in vitro. Prophylactic administration of SFN to K18-hACE2 mice prior to intranasal SARS-CoV-2 infection significantly decreased the viral load in the lungs and upper respiratory tract and reduced lung injury and pulmonary pathology compared to untreated infected mice. SFN treatment diminished immune cell activation in the lungs, including significantly lower recruitment of myeloid cells and a reduction in T cell activation and cytokine production. Our results suggest that SFN is a promising treatment for prevention of coronavirus infection or treatment of early disease.

7.
Am J Health Syst Pharm ; 76(18): 1413-1419, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31372630

RESUMO

PURPOSE: Inhaled epoprostenol and inhaled nitric oxide are pulmonary vasodilators commonly used in the management of acute respiratory distress syndrome and right ventricular failure; however, they have vastly different cost profiles. The purpose of the project was to transition from nitric oxide to epoprostenol as the inhaled pulmonary vasodilator (IPV) of choice in adult critically ill patients and evaluate the effect of the transition on associated usage and costs. METHODS: A single-center, prospective, before and after quality improvement project including adult patients receiving inhaled nitric oxide, inhaled epoprostenol, or both was conducted in 7 adult intensive care units, operating rooms, and postanesthesia care units of a tertiary care academic medical center. The total number of patients, hours of therapy, and costs for each agent were compared between stages of protocol implementation and annually. RESULTS: Seven hundred twenty-nine patients received inhaled nitric oxide, inhaled epoprostenol, or both during the study period. The monthly inhaled nitric oxide use in number of patients, hours, and cost decreased during all stages of the project (p < 0.01). The monthly inhaled epoprostenol use in number of patients, hours, and cost increased during all stages (p < 0.01). Overall, total IPV use increased during the study. However, despite this increase in usage, there was a 47% reduction in total IPV cost. CONCLUSION: Implementation of a staged protocol to introduce and expand inhaled epoprostenol use in adult critically ill patients resulted in decreased use and cost of inhaled nitric oxide. The total cost of all IPV was decreased by 47% despite increased IPV use.


Assuntos
Epoprostenol/administração & dosagem , Óxido Nítrico/administração & dosagem , Melhoria de Qualidade/organização & administração , Síndrome do Desconforto Respiratório/tratamento farmacológico , Vasodilatadores/administração & dosagem , Administração por Inalação , Adulto , Redução de Custos/economia , Redução de Custos/estatística & dados numéricos , Estado Terminal/terapia , Custos de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/economia , Uso de Medicamentos/estatística & dados numéricos , Epoprostenol/economia , Implementação de Plano de Saúde , Humanos , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Óxido Nítrico/economia , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Melhoria de Qualidade/economia , Melhoria de Qualidade/estatística & dados numéricos , Síndrome do Desconforto Respiratório/economia
8.
Pharmacotherapy ; 36(2): 166-73, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26799442

RESUMO

STUDY OBJECTIVES: To determine whether intraoperative continuous-infusion (CI) cefazolin reduces the incidence of surgical site infections (SSIs) compared with intermittent (INT) cefazolin dosing in patients undergoing coronary artery bypass grafting (CABG) on cardiopulmonary bypass (CPB); safety end points and protocol adherence comparing the two dosing strategies were also explored. DESIGN: Retrospective quasi-experimental (pre-post intervention) cohort study. SETTING: Large academic medical center. PATIENTS: A total of 516 adults who underwent CABG on CPB and received cefazolin intraoperatively between June 1, 2013, and December 31, 2014, were included. The INT cohort included 284 patients who underwent CABG from June 2013 to February 2014. The CI cohort included 232 patients who underwent CABG from April to December 2014, after an intraoperative CI cefazolin protocol for cardiac surgery patients undergoing CPB was adopted in March 2014. MEASUREMENTS AND MAIN RESULTS: The primary end point was incidence of SSIs, and safety end points of renal dysfunction and seizures were evaluated. Multivariable logistic regression analysis was used to determine the impact on SSIs when controlling for other risk factors. A subgroup analysis for this study included 2 months within each time period to evaluate protocol adherence. The overall incidence of SSIs was decreased in patients receiving CI cefazolin, although this did not reach statistical significance (4.6% in the INT cohort vs 1.7% in the CI cohort, p=0.116). Superficial SSIs were significantly reduced in the CI cohort (2.8% in the INT cohort vs 0.4% in the CI cohort, p=0.039). In the regression analysis, CI cefazolin decreased the odds of SSI by 66%, although it did not reach statistical significance (p=0.077). Safety end points were not significantly different between groups. Overall protocol adherence did not differ significantly between the cohorts: 77% in the INT cohort and 67% in the CI cohort (p=0.212). CONCLUSION: CI cefazolin significantly decreased the incidence of superficial SSIs compared with INT cefazolin in patients undergoing CABG on CPB, without increasing the risk for adverse effects. As this study was underpowered to detect a significant difference in overall SSIs, larger, randomized studies are required to validate the superiority of CI cefazolin.


Assuntos
Antibacterianos/administração & dosagem , Antibioticoprofilaxia , Cefazolina/administração & dosagem , Ponte de Artéria Coronária/efeitos adversos , Cuidados Intraoperatórios , Infecção da Ferida Cirúrgica/prevenção & controle , Centros Médicos Acadêmicos , Idoso , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/efeitos adversos , Baltimore/epidemiologia , Cefazolina/efeitos adversos , Cefazolina/uso terapêutico , Estudos de Coortes , Feminino , Humanos , Incidência , Infusões Intravenosas , Cuidados Intraoperatórios/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/fisiopatologia
9.
Pharmacotherapy ; 35(11): 1016-25, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26598094

RESUMO

Clostridium difficile infection (CDI) is the most common cause of nosocomial diarrhea and is associated with an increased risk of mortality. The use of probiotics and fecal microbiota transplantation (FMT) has been studied to reduce the incidence and severity of this infection, but variable efficacy and safety data have been reported. Probiotics are hypothesized to be effective in the management of CDI through a number of mechanisms that include maintenance of normal gastrointestinal flora, antimicrobial and antitoxin properties, and immunomodulatory effects. Despite promising results in small trials and meta-analyses, prospective, randomized, controlled trials have not demonstrated probiotics to be effective in the primary prevention of C. difficile-associated diarrhea (CDAD). Probiotics may be effective for secondary prevention in patients with recurrent CDI, but guidelines acknowledge the lack of compelling evidence. Trials are limited by the use of varying types of strains, numbers of strains, and doses of probiotics, as well the definitions of CDI and CDAD. FMT has been proposed as a method for restoring gut microbiota and has been shown to significantly increase the rate of cure in patients with recurrent CDI. Current studies have demonstrated minimal adverse effects, with no reports of transmission of infectious diseases; however, the optimal delivery method, sample preparation, and donor selection remain unclear. In this review, findings from recent literature are highlighted, and guideline recommendations for the use of these agents in the primary and secondary prevention of CDI are summarized.


Assuntos
Clostridioides difficile/crescimento & desenvolvimento , Infecção Hospitalar/terapia , Diarreia/terapia , Transplante de Microbiota Fecal , Prevenção Primária/métodos , Probióticos/uso terapêutico , Prevenção Secundária/métodos , Infecção Hospitalar/dietoterapia , Infecção Hospitalar/prevenção & controle , Diarreia/dietoterapia , Diarreia/prevenção & controle , Humanos , Guias de Prática Clínica como Assunto , Recidiva
10.
J Infect Dis ; 205(4): 595-602, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22198962

RESUMO

BACKGROUND: Preclinical evaluation of tuberculosis drugs is generally limited to mice. However, necrosis and hypoxia, key features of human tuberculosis lesions, are lacking in conventional mouse strains. METHODS: We used C3HeB/FeJ mice, which develop necrotic lesions in response to Mycobacterium tuberculosis infection. Positron emission tomography in live infected animals, postmortem pimonidazole immunohistochemistry, and bacterial gene expression analyses were used to assess whether tuberculosis lesions in C3HeB/FeJ are hypoxic. Efficacy of combination drug treatment, including PA-824, active against M. tuberculosis under hypoxic conditions, was also evaluated. RESULTS: Tuberculosis lesions in C3HeB/FeJ (but not BALB/c) were found to be hypoxic and associated with up-regulation of known hypoxia-associated bacterial genes (P < .001). Contrary to sustained activity reported elsewhere in BALB/c mice, moxifloxacin and pyrazinamide (MZ) combination was not bactericidal beyond 3 weeks in C3HeB/FeJ. Although PA-824 added significant activity, the novel combination of PA-824 and MZ was less effective than the standard first-line regimen in C3HeB/FeJ. CONCLUSIONS: We demonstrate that tuberculosis lesions in C3HeB/FeJ are hypoxic. Activities of some key tuberculosis drug regimens in development are represented differently in C3HeB/FeJ versus BALB/c mice. Because C3HeB/FeJ display key features of human tuberculosis, this strain warrants evaluation as a more pathologically relevant model for preclinical studies.


Assuntos
Granuloma/complicações , Granuloma/patologia , Hipóxia/patologia , Mycobacterium tuberculosis/patogenicidade , Tuberculose/patologia , Animais , Antituberculosos/administração & dosagem , Compostos Aza/administração & dosagem , Modelos Animais de Doenças , Fluoroquinolonas , Perfilação da Expressão Gênica , Genes Bacterianos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C3H , Moxifloxacina , Nitroimidazóis/administração & dosagem , Tomografia por Emissão de Pósitrons , Pirazinamida/administração & dosagem , Quinolinas/administração & dosagem , Resultado do Tratamento , Tuberculose/tratamento farmacológico
11.
Antimicrob Agents Chemother ; 53(11): 4879-84, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19738022

RESUMO

Tools for monitoring response to tuberculosis (TB) treatment are time-consuming and resource intensive. Noninvasive biomarkers have the potential to accelerate TB drug development, but to date, little progress has been made in utilizing imaging technologies. Therefore, in this study, we used noninvasive imaging to monitor response to TB treatment. BALB/c and C3HeB/FeJ mice were aerosol infected with Mycobacterium tuberculosis and administered bactericidal (standard and highly active) or bacteriostatic TB drug regimens. Serial pulmonary [(18)F]-2-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET) was compared with standard microbiologic methods to monitor the response to treatment. [(18)F]FDG-PET correctly identified the bactericidal activity of the drug regimens. Imaging required fewer animals; was available in real time, as opposed to having CFU counts 4 weeks later; and could also detect TB relapse in a time frame similar to that of the standard method. Lesion-specific [(18)F]FDG-PET activity also broadly correlated with TB treatment in C3HeB/FeJ mice that develop caseating lesions. These studies demonstrate the application of noninvasive imaging to monitor TB treatment response. By reducing animal numbers, these biomarkers will allow cost-effective studies of more expensive animal models of TB. Validated markers may also be useful as "point-of-care" methods to monitor TB treatment in humans.


Assuntos
Antituberculosos/farmacologia , Fluordesoxiglucose F18 , Pulmão/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tuberculose/tratamento farmacológico , Animais , Feminino , Granuloma/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Recidiva , Tuberculose/diagnóstico por imagem
12.
PLoS One ; 4(7): e6297, 2009 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-19606217

RESUMO

BACKGROUND: Bacteria can be selectively imaged in experimentally-infected animals using exogenously administered 1-(2'deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-[(125)I]-iodouracil ([(125)I]-FIAU), a nucleoside analog substrate for bacterial thymidine kinase (TK). Our goal was to use this reporter and develop non-invasive methods to detect and localize Mycobacterium tuberculosis. METHODOLOGY/PRINCIPAL FINDINGS: We engineered a M. tuberculosis strain with chromosomally integrated bacterial TK under the control of hsp60 -- a strong constitutive mycobacterial promoter. [(125)I]FIAU uptake, antimicrobial susceptibilities and in vivo growth characteristics were evaluated for this strain. Using single photon emission computed tomography (SPECT), M. tuberculosis P(hsp60) TK strain was evaluated in experimentally-infected BALB/c and C3HeB/FeJ mice using the thigh inoculation or low-dose aerosol infection models. M. tuberculosis P(hsp60) TK strain actively accumulated [(125)I]FIAU in vitro. Growth characteristics of the TK strain and susceptibility to common anti-tuberculous drugs were similar to the wild-type parent strain. M. tuberculosis P(hsp60) TK strain was stable in vivo and SPECT imaging could detect and localize this strain in both animal models tested. CONCLUSION: We have developed a novel tool for non-invasive assessment of M. tuberculosis in live experimentally-infected animals. This tool will allow real-time pathogenesis studies in animal models of TB and has the potential to simplify preclinical studies and accelerate TB research.


Assuntos
Mycobacterium tuberculosis/enzimologia , Timidina Quinase/metabolismo , Animais , Arabinofuranosiluracila/administração & dosagem , Arabinofuranosiluracila/análogos & derivados , Cromossomos Bacterianos , Feminino , Radioisótopos do Iodo/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Regiões Promotoras Genéticas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA