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BACKGROUND: Despite the breadth of data supporting evidence-based practice for sepsis care in high-resource settings, there are relatively few data to guide the management of sepsis in low-resource settings, particularly in areas where HIV and tuberculosis (TB) are prevalent. Furthermore, few studies had broadened sepsis parameters to include all patients with acute infectious illness or followed patients up after hospital discharge. Understanding the epidemiology and outcomes of acute infections in a local context is the critical first step to developing locally informed targeted management strategies. OBJECTIVES: To quantify and describe the incidence of and risk factors for mortality in a cohort of patients with undifferentiated acute infectious illnesses who presented to an emergency department (ED) in the Eastern Cape region of South Africa (SA). METHODS: In this prospective cohort study, patients with suspected acute infectious illness were enrolled at a district casualty ward in Mthatha, SA, between 1 July and 1 September 2017. Demographic data, interventions, diagnostic studies and disposition were prospectively collected during the initial encounter and during the hospital stay. Follow-up was conducted both in hospital and via phone interviews 30 days after the index visit. RESULTS: A total of 301 patients presented to the ED with acute infectious illness during the study period, of whom 54.8% had complete 30-day follow-up. Of the study population, only 5.7% had a complete set of vital signs (heart rate, respiratory rate, blood pressure and temperature) documented. Of the cohort, 51.8% had HIV and 32.9% active or treated TB; 25.2% of patients died within 30 days. Accounting for medical history, diagnosis and ED interventions, risk of mortality was independently associated with age (odds ratio (OR) 1.03; 95% confidence interval (CI) 1.00 - 1.06), HIV-positive status (OR 4.10; 95% CI 1.44 - 11.67) and Quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) score (OR 1.90; 95% CI 1.14 - 3.19) in an adjusted model. No ED interventions were protective for mortality, with intravenous fluid administration associated with increased 30-day mortality in this cohort (OR 3.65; 95% CI 1.38 - 9.62). CONCLUSIONS: Among adults with suspected acute infectious illness in Mthatha, SA, 30-day mortality was concerningly high. Mortality was highest in patients with concomitant HIV infection. In particular, vital sign assessment to identify possible sepsis in this cohort is crucial, as it affects mortality to a meaningful extent, yet is often unavailable. Future research is needed on the management of sepsis in low-resource settings, particularly in HIV-positive individuals.
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Enfermedad Crítica/mortalidad , Infecciones por VIH/mortalidad , Afecciones Crónicas Múltiples/mortalidad , Sepsis/mortalidad , Adulto , Anciano , Estudios de Cohortes , Comorbilidad , Servicio de Urgencia en Hospital/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , SudáfricaRESUMEN
BACKGROUND: Symptomatic hyperlactataemia and lactic acidosis (SHLA) are potentially life-threatening complications associated with stavudine (d4T), an antiretroviral therapy (ART) drug widely used in developing countries. METHODS: Cases comprised all symptomatic patients with measured lactates >or= 5 mmol/L referred to a South African hospital between August 2003 and November 2005. Matched controls were selected according to facility and duration on ART. RESULTS: Seventy-one cases and 142 controls were included in the study. The majority of cases presented between 6 and 18 months on ART. Female sex [adjusted odds ratio (AOR) 23.4; 95% confidence interval (CI) 4.0-136.6], a baseline weight between 60 and 75 kg (AOR 4.5; 95% CI 1.4-14.1) or, in particular, >or= 75 kg (AOR 19.4; 95% CI 4.1-82.5) at ART initiation and gaining >or= 6 kg in the first 3 months on therapy (AOR 3.5; 95% CI 1.3-9.5) were independent risk factors identifying patients who may subsequently develop SHLA. Weight loss of >or= 2 kg (AOR 6.1; 95% CI 2.0-18.3), a rise in alanine aminotransferase (ALT) >or= 10 U/L (AOR 3.1; 95% CI 1.1-8.9), the presence of at least one of three major symptoms (vomiting, nausea and abdominal pains) of SHLA (AOR 12.6; 95% CI 3.3-47.2) and peripheral neuropathy (AOR 3.4; 95% CI 1.1-9.8) were the clinical parameters that were most able to identify patients with early manifestations of SHLA. CONCLUSIONS: This is the first case-control study for SHLA in Southern Africa. Given these findings, we advise that stavudine is avoided in overweight women. Weight loss, a rise in ALT, peripheral neuropathy and/or gastrointestinal symptoms should prompt healthcare workers to assess for SHLA, especially at between 6 and 18 months on ART.
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Acidosis Láctica/inducido químicamente , Fármacos Anti-VIH/efectos adversos , Inhibidores de la Transcriptasa Inversa/efectos adversos , Estavudina/efectos adversos , Acidosis Láctica/sangre , Adulto , Alanina Transaminasa/metabolismo , Fármacos Anti-VIH/administración & dosificación , Países en Desarrollo , Esquema de Medicación , Métodos Epidemiológicos , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Sobrepeso/complicaciones , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Embarazo , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Sudáfrica , Estavudina/administración & dosificación , Pérdida de PesoRESUMEN
PCR-amplification has been used to screen 75 isolates of the Burkholderia cepacia complex for the cblA pilin gene. PCR-amplified products of the correct size (664 bp) were cloned and sequenced and the sequences compared. Apart from in the control, epidemic cystic fibrosis (CF)-associated B. cepacia lineage we also identified, for the first time, cblA genes in a unique, non-CF clinical isolate from France and a plant (onion) pathogenic isolate from Italy. The sequence of the cblA gene amplified from the clinical isolate was more diverged from the epidemic lineage than that amplified from the onion pathogenic isolate.
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Burkholderia cepacia/genética , Burkholderia/genética , Genes Bacterianos , Proteínas de la Membrana/genética , Secuencia de Aminoácidos , Burkholderia/aislamiento & purificación , Infecciones por Burkholderia/microbiología , Burkholderia cepacia/aislamiento & purificación , Clonación Molecular , Fibrosis Quística/microbiología , Escherichia coli/genética , Proteínas Fimbrias , Humanos , Proteínas de la Membrana/química , Datos de Secuencia Molecular , Cebollas/microbiología , Operón , Filogenia , Plantas/microbiología , Reacción en Cadena de la Polimerasa , Salmonella typhimurium/genéticaRESUMEN
The genus Burkholderia comprises over 28 species and species-specific, recA-based polymerase chain reaction (PCR) tests are available for several species, but not for some soil-inhabiting species including B. fungorum. Previous analysis of several novel rhizospheric, environmental isolates belonging to the B. cepacia complex suggested they may be closely related to B. fungorum. To discover any relationship between these isolates and B. fungorum we set out to clone and sequence a portion of the B. fungorum recA gene in order to design species-specific primer pairs for use in a recA-based PCR assay. Using a similar procedure we extended the recA-based PCR assay to identify B. sacchari and B. caledonica, two additional soil-inhabiting Burkholderia spp.
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Burkholderia/genética , Reacción en Cadena de la Polimerasa/métodos , Rec A Recombinasas/genética , Burkholderia/clasificación , Burkholderia/aislamiento & purificación , Filogenia , Microbiología del Suelo , Especificidad de la EspecieRESUMEN
A reversed-phase HPLC method previously developed for the analysis of progesterone and its major metabolites has been transferred successfully to a capillary electrochromatography (CEC) system. Procedures for fabricating packed capillaries and the modifications made to the capillary electropherograph which allow operation in the CEC mode without pressurisation are described. The dependence of electroosmotic flow on electric field strength, pH and organic modifier content is discussed. Direct comparison with HPLC shows that CEC provides useful gains in efficiency and speed of analysis and requires vastly reduced amounts of both chromatographic phases and material for analysis. On-line concentration is described which allows the lower sensitivity of CEC to be offset by injecting analytes from a non-eluting solution. Examination of steroids in plasma demonstrates that the superior separation by CEC is maintained in a complex biological matrix.
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Cromatografía Líquida de Alta Presión , Cromatografía/métodos , Esteroides/sangre , 17-alfa-Hidroxiprogesterona/sangre , 20-alfa-Dihidroprogesterona/sangre , Acetonitrilos , Androstenodiona/sangre , Concentración de Iones de Hidrógeno , Metanol , Noretindrona/sangre , Progesterona/sangre , Sensibilidad y Especificidad , Solventes , Testosterona/sangreRESUMEN
Fatty acid profiling was used to study variation amongst strains of Xanthomonas campestris pv. vasculorum (Xcv). They could be divided into five groups using cellular fatty acid profiles. Group A strains represent a new and little known taxon and all came from plants of broom bamboo (Thysanolaena maxima) from Mauritius. Group B strains included the Xcv pathotype reference strain and were from palms, broom bamboo and sugarcane from Mauritius, Reunion and Australia. Group C contained southern African and Malagasy strains from sugarcane and maize, together with X. campestris pv. holcicola strain. No Mascarene strains fell into this group. Group D strains isolated from sugarcane, maize and royal palm (Roystonea regia) were from Mauritius and Reunion, the earliest known strains coming from Réunion. These groups represented in the Mascarene Islands possibly belong to three different Xanthomonas species. A further Group E comprised one Xcv strain (NCPPB 182) from Puerto Rico, one X. vasicola pv. holcicola strain plus 6 other unclassified Xanthomonas strains causing red stripe disease symptoms in sugarcane. Three of these groups occur on Mauritius and two occur on Réunion. Group B strains originally caused serious problems in noble canes. As resistant interspecific hybrids were introduced, group D strains appeared in Mauritius possibly being introduced from Reunion but having similar host ranges within the Gramineae and Palmae. The findings that 3 of these groups (A, B, D) can cause gumming disease in a grass species (T. maxima) and that 2 of them (B, D) also cause gumming disease in sugar cane (Gramineae) and palms (Palmae) is unusual.
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Ácidos Grasos/análisis , Enfermedades de las Plantas/microbiología , Plantas Comestibles/microbiología , Xanthomonas campestris/química , Xanthomonas campestris/clasificación , Islas del Oceano Índico , Mauricio , ReuniónRESUMEN
ABSTRACT In a recent Letter to the Editor of Phytopathology, proposals were made for endorsement and for rejection of selected names of plant pathogenic Pseudomonas spp. and Xanthomonas spp. We believe that support for, and rejection of, several names was based on misconceptions concerning the Approved Lists of Bacterial Names and entails misinterpretations of several Rules of the International Code of Nomenclature of Bacteria. This letter aims to clarify those misconceptions and misinterpretations.
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The naturally occurring complex organic acids, chlorogenic acid, gallic acid and quinic acid, at concentrations of 100, 500 and 1000 mg l-1 were evaluated for effects on the growth of three spoilage strains of Lactobacillus collinoides and one of Lact. brevis in acid tomato broth containing 5% (v/v) ethanol at pH 4.8. During early stages of growth, all the complex acids at each concentration stimulated growth of Lact. collinoides but not of Lact. brevis. During stationary phase, chlorogenic and gallic acids produced greater cell densities of all strains, whereas quinic acid generally had less effect. The presence of these complex acids in fruit products may increase the requirement for added preservative in order to prevent spoilage by certain strains of lactic acid bacteria.
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The clarification of milk by addition of solutions of Triton X-100 and EDTA after digestion of added Hide Powder Azure (HPA) was found to provide a simple method of determining the extracellular proteinase activity of Gram-negative psychrotrophic bacteria in pasteurized whole milk. The light absorbance of the clarified HPA digestion product was measured directly, after a brief incubation period, and was stable to storage of samples in diffuse daylight for at least 2 d. Proteinase produced by growth in refrigerated whole milk of as few as 2.5 X 10(6) cfu ml-1 of Pseudomonas fluorescens AR11 was detected.
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Endopeptidasas/análisis , Leche/enzimología , Pseudomonas fluorescens/enzimología , Animales , Bovinos , Técnicas In VitroRESUMEN
Three strains of psychrotrophic Pseudomonas spp., each with different lipolytic and proteolytic phenotypes (including a proteinase-deficient mutant), were cultured separately in whole milk at 7 degrees C. Growth rates were the same during logarithmic growth phase, but during early stationary phase the cell densities were related to the activities of lipase and proteinase in the cultures. Only one strain underwent pronounced death phase. Proteinase activity was not detected in the culture of the proteinase-deficient mutant, but in those of the other strains it increased to a plateau, or continued to increase linearly. Lipase activity of the culture of each strain reached a peak in early stationary phase; in late stationary phase activity was highest for the proteinase-deficient mutant strain where degradation of lipase by bacterial proteinase would have been least. The ability of psychrotrophic bacteria both to survive for long periods and to produce high levels of proteinases and lipases on prolonged incubation in milk emphasizes the spoilage potential arising from psychrotrophic bacteria in inadequately cleaned dairy equipment.
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Endopeptidasas/metabolismo , Lipasa/metabolismo , Leche/microbiología , Pseudomonas/enzimología , Animales , Técnicas In Vitro , Leche/enzimología , Pseudomonas/crecimiento & desarrollo , Pseudomonas fluorescens/enzimología , Pseudomonas fluorescens/crecimiento & desarrolloRESUMEN
Hydroxycinnamic acids and their derivatives occur widely in plants, fruits and wine. The effect of the common hydroxycinnamic acids (caffeic, coumaric and ferulic acids), at concentrations of 100 and 500 mg l-1, on growth of 11 strains of spoilage yeasts was measured spectrophotometrically and compared with that of potassium sorbate. Ferulic acid was the most generally inhibitory hydroxycinnamic acid. At 500 mg l-1 it appreciably inhibited Pichia anomala, Debaryomyces hansenii and Saccharomyces cerevisiae and prevented detectable growth of one strain each of P. anomala and D. hansenii. Caffeic acid was the least inhibitory compound and coumaric acid had an intermediate effect. The more resistant strains of yeast were P. membranaefaciens, Saccharomycodes ludwigii and Zygosaccharomyces bailii. Sensitivity to hydroxycinnamic acid was, in general, associated with sensitivity to potassium sorbate; at a given concentration potassium sorbate was more inhibitory than were any of the hydroxycinnamic acids.
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Bebidas Alcohólicas/microbiología , Cinamatos/farmacología , Conservantes de Alimentos/farmacología , Ácido Sórbico/farmacología , Levaduras/efectos de los fármacos , Ácidos Cafeicos/farmacología , Ácidos Cumáricos/farmacología , Relación Dosis-Respuesta a Droga , Especificidad de la EspecieRESUMEN
The aminoglycosides are a large and diverse class of antibiotics that characteristically contain two or more aminosugars linked by glycosidic bonds to an aminocyclitol component. Structures are presented for over 30 of the most important members of this family of compounds. The use of aminoglycosides in clinical and veterinary medicine and in agriculture is described. Qualitative methods for aminoglycoside analysis include X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). The major part of this article comprises a comprehensive review of quantitative methods for the determination of aminoglycosides. These are microbiological assay, radiochemical assay, radioimmunoassay, enzyme immunoassay, fluoroimmunoassay and other immunoassays, spectrophotometric and other non-separative methods, gas chromatography (GC), thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), and capillary electrophoresis (CE). Simple spectrophotometric methods may be adequate for the assay of bulk pharmaceuticals and their formulations. Microbiological assays make useful semi-quantitative screening tests for the analysis of veterinary drug residues in food, but rapid enzyme immunoassays are more suitable for accurate measurements of aminoglycosides in complex matrices. Automated immunoassays are the most appropriate methods for serum aminoglycoside determinations during therapeutic drug monitoring. HPLC techniques provide the specificity and sensitivity required for pharmacokinetic and other research studies, while HPLC-MS is employed for the confirmation of veterinary drug residues. The potential for further development of chromatographic and CE methods for the analysis of biological samples is outlined.
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Aminoglicósidos/análisis , Cromatografía/métodos , Análisis EspectralRESUMEN
The lipids from Arthrobacter crystallopoietes, A. pascens, and A. globiformis were investigated. Each strain contained three glycolipids, a monogalactosyl diglyceride, a digalactosyl diglyceride, and a dimannosyl diglyceride, and traces of triand tetraglycosyl diglycerides. The phospholipids in all three strains consisted of bisphosphatidylglycerol, phosphatidylglycerol, and phosphatidylmyoinositol. No evidence could be obtained for the occurrence of mannophosphoinositides. Analysis of the fatty acids by gas-liquid chromatography showed that they are predominantly C(15:0)anteiso and C(17:0)anteiso compounds. No significant differences were observed in the composition of lipids extracted from homogeneous cell preparations of the rod and sphere forms of A. crystallopoietes.
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Arthrobacter/análisis , Ácidos Grasos/análisis , Glucolípidos/análisis , Fosfolípidos/análisis , Arthrobacter/citología , Cromatografía de Gases , Cromatografía en Papel , Cromatografía en Capa Delgada , Liofilización , Galactosa/análisis , Glicéridos/análisis , Glicerol/análisis , Manosa/análisis , Fosfatidilinositoles/análisis , Dióxido de Silicio , Solventes , Especificidad de la Especie , EspectrofotometríaRESUMEN
Four classes of bovine serum lipoproteins were isolated by precipitation with dextran sulfate, ultracentrifugation, and preparative electrophoresis on polyacrylamide gel. Very low density lipoprotein (d less than 1.019 g/ml) was related immunologically to low density lipoprotein-two (d 1.039 to 1.060 g/ml) and high density lipoprotein (d 1.060 to 1.210 g/ml) was related immunologically to low density lipoprotein-one (d 1.019 to 1.039 g/ml), but the two pairs were immunologically distinct. The major N-terminal amino acid of both high density lipoprotein and low density lipoprotein-one was aspartic acid, and that of low density lipoprotein-two was glutamic acid. Very low density lipoprotein had both aspartic acid and glutamic acid as the major N-terminal amino acids. None of the lipoproteins was identical with any other with respect to amino acid composition, but high density lipoprotein and low density lipoprotein-one were similar to each other and different from low density lipoprotein-two. Very low density lipoprotein was similar to both low density lipoprotein-one and low density lipoprotein-two. It is concluded that the proteins of high density lipoprotein and of low density lipoprotein-one are related and are different from that of low density lipoprotein-two. The protein of very low density lipoprotein is related to that of low density lipoprotein-two but may contain polypeptides of high density lipoprotein or low density lipoprotein-one.
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Lipoproteínas , Aminoácidos/sangre , Animales , Apoproteínas/sangre , Bovinos , Femenino , Lipoproteínas/sangre , Lipoproteínas/inmunología , Lipoproteínas HDL/sangre , Lipoproteínas HDL/inmunología , Lipoproteínas LDL/sangre , Lipoproteínas LDL/inmunología , Lipoproteínas VLDL/sangre , Lipoproteínas VLDL/inmunologíaRESUMEN
Pure samples of low density lipoprotein-one (d 1.019 to 1.039 g/ml), low density lipoprotein-two (d 1.039 to 1.060 g/ml), and high density lipoprotein (d 1.060 to 1.210 g/ml) were isolated from bovine serum and their properties studied in the analytical ultracentrifuge. Approach-to-equilibrium experiments indicated that the lipoprotein classes were homogeneous. Molecular weights of the lipoproteins given by this method (low density lipoprotein-one, 1.14 x 10(6); low density lipoprotein-two, 2.37 x 10(6); high density lipoprotein, .576 x 10(6)) agreed well with those obtained by a high-speed-equilibrium method (1.03 x 10(6), 2.15 x 10(6), and .567 x 10(6)). Linear plots of flotation rate (corrected for viscosity) against the density of the medium were obtained in sedimentation velocity experiments and on extrapolation gave values for the hydrated density of 1.032 g/ml for low density lipoprotein-one, 1.044 g/ml for low density lipoprotein-two, and 1.071 g/ml for high density lipoprotein. The density of the material which would have to be added to high density lipoprotein to give it the physical properties of low density lipoprotein one was less than 1 g/ml, which suggested that it was predominantly lipid.
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Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Animales , Bovinos , Femenino , Peso Molecular , UltracentrifugaciónRESUMEN
The four classes of lipoproteins (one of very low density, two of low density, and one of high density) were isolated from the serum of a lactating Friesian cow. The proportions of protein and of the different lipid classes were determined in each lipoprotein. Triglycerides predominated in the very low density lipoprotein, and cholesteryl esters and phospholipids in the others. The triglycerides of the very low density lipoprotein were richer in oleic acid than were those of the low density lipoproteins, but its cholesteryl esters were relatively poorer in linoleic and linolenic acid than were those of any of the others. Phytanic acid (3, 7, 11, 15-tetramethylhexadecan-1-oic acid) was in all lipoproteins except those of very low density; it was not in cholesteryl esters but was abundant in triglycerides, particularly in those of the low density lipoproteins. Hydrolysis of the triglycerides of very low density lipoprotein with pancreatic lipase showed that 82% of their stearic acid was esterified to the 1- and 3-positions of glycerol and that 64% of their palmitic acid was esterified to the 2-position.
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Bovinos/sangre , Lípidos/sangre , Lipoproteínas/sangre , Animales , Colesterol/sangre , Ésteres/sangre , Femenino , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lipoproteínas VLDL/sangre , Fosfolípidos/sangre , Triglicéridos/sangreRESUMEN
We demonstrated that oxidative stress plays a role in freeze-thaw-induced killing of Campylobacter coli following analysis of mutants deficient in key antioxidant functions. Superoxide anions, but not H(2)O(2), were formed during the freeze-thaw process. However, a failure to detoxify superoxide anions may lead to spontaneous disproportionation of the radicals to H(2)O(2).
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Campylobacter coli/enzimología , Campylobacter coli/fisiología , Catalasa/metabolismo , Congelación , Superóxido Dismutasa/metabolismo , Campylobacter coli/genética , Catalasa/genética , Recuento de Colonia Microbiana , Mutación , Superóxido Dismutasa/genéticaRESUMEN
Following the development of a sensitive high-performance liquid chromatographic (HPLC) assay for gentamicin in biological matrices, the utility of this assay for the determination of other clinically important aminoglycosides (neomycin, netilmicin and sisomicin) in bacterial culture media or plasma is demonstrated. The high sensitivity of the assay enables direct measurement of the aminoglycoside content of bacterial cells cultured in the presence of unlabelled drug.
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Antibacterianos/análisis , Enterococcus faecalis/metabolismo , Neomicina/análisis , Netilmicina/análisis , Sisomicina/análisis , Antibacterianos/sangre , Cromatografía Líquida de Alta Presión , Humanos , Neomicina/sangre , Netilmicina/sangre , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sisomicina/sangreRESUMEN
AIMS: The development of a fluorogenic, 5' nuclease, TaqMan PCR assay for the detection of Ri-plasmids from root mat inducing Agrobacterium biovar 1 strains. METHODS AND RESULTS: A TaqMan probe and primer set were designed within the T-DNA sequence of a known root mat inducing Agrobacterium strain. One hundred and ten Agrobacterium and closely related bacteria were tested using this novel PCR and compared with results from a conventional PCR which detects Ti and Ri-plasmids. The Agrobacterium selective media, Medium 1A was modified into broth form for use as an enrichment of the pathogen from samples prior to the TaqMan PCR. CONCLUSIONS: The root mat pathogen was detected successfully from a range of sample types using the enriched fluorogenic PCR assay, negating the need for complex DNA extraction procedures and post-PCR processing techniques such as gel electrophoresis. The technique is therefore a rapid and cost-effective detection method. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first known report of a fluorogenic, 5' nuclease, TaqMan assay designed to detect an Agrobacterium plant pathogen. The method can be used as a model system for the detection of other Agrobacterium pathogens.