Aims: To isolate and characterize phosphate-solubilizing strains from a constrained environment such as the Salado River Basin and to assess their phosphate-solubilizing mechanisms, to further ...selection of the most promising strains to inoculate and improve the implantation and persistence of Lotus tenuis in the most important area devoted to meat-cow production in Argentina. Methods and Results: Fifty isolates were obtained and through BOX-PCR analysis, 17 non-redundant strains were identified. Subsequently, they were found to be related to Pantoea, Erwinia, Pseudomonas, Rhizobium and Enterobacter genera, via 16S rRNA gene sequence analysis. This was in agreement with the clusters obtained by antibiotic resistance analysis. All isolates were tested for their phosphate-solubilizing activity and selected strains were inoculated onto L. tenuis plants. The most efficient isolate, was identified as Pantoea eucalypti, a novel species in terms of plant growth-promoting rhizobacteria. Conclusions: The isolates obtained in this study showed a significant in vitro plant-growth promoting activity onto Lotus tenuis and the best of them solubilizes phosphate mainly via induction of the metabolism through secretion and oxidation of gluconic acid. Singnificance and Impact of the Study: The use of these bacteria as bioinoculants, alone or in combination with nitrogen-fixing micro-organisms, could be a sustainable practice to facilitate the nutrient supply to Lotus tenuis plants and preventing negative side-effects such as eutrophication.
En este trabajo se estudia el crecimiento de cepas de Bradyrllizobium y Rhizobium, en sistema batch con el propósito de obtener suspensiones de muy alta concentración celular. Para tal fin se ...considera la influencia de la aeración y de los constituyentes del medio de cultivo. Las experiencias fueron realizadas en frascos er1enmeyersen un agitador rotatorio y en fermentador con agitación mec41nica.La evolución del crecimiento celular fue determinada en base a medidas de densidad óptica, recuento de células viables, y peso seco. Usando el medio seleccionado y las cepas de Rhizobium meliloti B 36, B 399, Rhizobium trifolii A 113, Rhizobium Ioti LL 22, Rhizobium leguminoserum O 70 Y Bradyrhizobium japonicum E 109, E 110 Y E 45 fue posible obtener concentraciones de microorganismos de 6 x 1010 a 1 x 1011 células viables/mi en 48 y 96 horas de proceso, que corresponden a valores de peso seco del orden de 10 a 12 gil. Además, se determinaron valores de presión osmótica del orden de 300 miliosmoles. Por último, es de destacar que las cepas desarrolladas en los nuevos medios seleccionados mantienen su capacidad fisiológica.
Aims: To isolate and characterize phosphate-solubilizing strains from a constrained environment such as the Salado River Basin and to assess their phosphate-solubilizing mechanisms, to further ...selection of the most promising strains to inoculate and improve the implantation and persistence of Lotus tenuis in the most important area devoted to meat-cow production in Argentina. Methods and Results: Fifty isolates were obtained and through BOX-PCR analysis, 17 non-redundant strains were identified. Subsequently, they were found to be related to Pantoea, Erwinia, Pseudomonas, Rhizobium and Enterobacter genera, via 16S rRNA gene sequence analysis. This was in agreement with the clusters obtained by antibiotic resistance analysis. All isolates were tested for their phosphate-solubilizing activity and selected strains were inoculated onto L. tenuis plants. The most efficient isolate, was identified as Pantoea eucalypti, a novel species in terms of plant growth-promoting rhizobacteria. Conclusions: The isolates obtained in this study showed a significant in vitro plant-growth promoting activity onto Lotus tenuis and the best of them solubilizes phosphate mainly via induction of the metabolism through secretion and oxidation of gluconic acid. Singnificance and Impact of the Study: The use of these bacteria as bioinoculants, alone or in combination with nitrogen-fixing micro-organisms, could be a sustainable practice to facilitate the nutrient supply to Lotus tenuis plants and preventing negative side-effects such as eutrophication.
The explosive and explodibility parameters of a new organic nitrate drug, ITF 296, have been studied. ITF 296 does not possess explosive properties, as determined by European Community standard ...testing methods (heat, impact and friction tests). The decomposition and auto-ignition temperature, determined by differential scanning calorimetry, are substantially higher than the working temperature which can be achieved with this compound. However, the explodibility properties of ITF 296, as determined by a hot-wire ignition method (Hartmann modified apparatus) and a heat oven auto-ignition method, place ITF 296 in Dust Hazard Class I. The addition of anhydrous dibasic calcium phosphate strongly attenuates the explodability properties of ITF 296 and, consequently, the need for expensive anti-explosion measures in the development and production environment.
The growth rate of different strains of Bradyrhizobium and Rhizobium was studied in media containing amaranth seed meal instead of yeast extract. Results obtained in erlenmeyer flasks and stirred ...fermenters show that both Bradyrhizobium japonicum strains E109, E110, 5019, 587 and Rhizobium meliloti strains B36, B323, B399, Lq sub(22), Lq sub(42), Lq sub(51) and U sub(322), grow satisfactorily in amaranth seed meal medium. Cell count obtained for the strains tested was greater than 4 x 10 super(10) viable cells.ml super(-1). Amaranth seed meal (4 g.l super(-1)) is a suitable component for culture media that can be used instead of yeast extract.
The growth rate of different strains of Bradyrhizobium and Rhizobium was studied in media containing amaranth seed meal instead of yeast extract. Results obtained in erlenmeyer flasks and stirred ...fermenters show that both Bradyrhizobium japonicum strains E109, E110, 5019, 587 and Rhizobium melilotistrains B36, B323, B399, Lq^sub 22^, Lq^sub 42^, Lq^sub 51^ and U^sub 322^, grow satisfactorily in amaranth seed meal medium. Cell count obtained for the strains tested was greater than 4 × 10^sup 10^ viable cells.ml^sup -1^. Amaranth seed meal (4 g.l^sup -1^) is a suitable component for culture media that can be used instead of yeast extract.PUBLICATION ABSTRACT
We studied alpha-amylase production by Bacillus subtilis strain NRRL 3411, the effect of heat shock, concentration and nature of the growth factors, carbon and nitrogen source. We also considered the ...stability of the cell-free enzymatic culture by using spores heat shocked at 100 degrees C for 10 minutes in media containing lactose, casein, yeast extract and minerals. We achieved a final value of 1400 units of alpha-amylase after 72 h of process. It was also found that by adding 20% glycerol and 1% sodium benzoate, cultures were stable at 20 degrees C for 30 days.
Severe streptococcal complications in varicella Héraud, M C; Loriette, Y; Grassano, A ...
Archives de pédiatrie : organe officiel de la Société française de pédiatrie
4, Številka:
5
Journal Article
Recenzirano
An increase in the incidence of group A beta hemolytic streptococcal (GABHS) infections in children has been recently noted with a frequent association with varicella.
Two children, 3 and 4.5 years ...old, developed varicella. The first one was febrile and presented a phlyctene on his left foot. Few hours after his admission, he presented a septic shock; GABHS was isolated from blood. Despite immediate adapted antibiotherapy, he developed a right tibial osteomyelitis with abscess. The second child also developed varicella and was hospitalized because of fever, bad general condition, right cervical adenitis and edema on the left wrist. Edema rapidly extended to the hand and upper arm. One purulent lesion was noted on the upper arm from whom Staphylococcus aureus and GABHS were isolated. Blood samples were sterile. The clinical course was favorable with adapted antibiotherapy. A cutaneous desquamation was observed on the 9th day and we concluded that it was a GABHS cellulitis.
These two cases confirm the recent report of increase in GABHS infections associated with varicella. Such complications must be looked for in patients with varicella remaining abnormally febrile and/or presenting unusual manifestations.
Depuis quelques années, il est décrit une augmentation de l'incidence des infections graves à streptocoque bêta-hémolytique de groupe A (SBHGA) chez l'enfant, ainsi que la fréquence de leur ...association avec la varicelle.
Observations.
— Deux enfants âgés de 3 ans et 4 ans et demi, présentant une varicelle, ont été hospitalisés en mai-juin 1996. Le premier, très fébrile, présentait une éruption, d'importance moyenne, avec une lésion phlycténulaire au niveau du pied gauche associée à une boiterie droite. Quelques heures après son arrivée, survient un choc septique avec isolement d'un SBHGA dans l'hémoculture. Malgré la mise en route rapide d'une antibiothérapie adaptée avec amélioration rapide de l'état clinique, il va développer une ostéomyélite tibiale droite avec abcès sous-périosté. Le second enfant est hospitalisé pour fièvre importante, altération de l'état général, adénite cervicale droite et œdème du poignet gauche. L'éruption varicelleuse est importante. L'œdème du poignet va rapidement s'étendre à l'ensemble de la main et gagner l'avant-bras. Une lésion varicelleuse purulente est alors observée au niveau de l'avant-bras et un prélèvement retrouvera un staphylocoque coagulase négative et un SBHGA. Les hémocultures sont restées négatives. L'évolution sera favorable sous antibiothérapie adaptée. La survenue au 9
e jour d'évolution d'une desquamation cutanée généralisée a permis de conclure à une cellulite à streptocoque.
Conclusion.
— Ces deux observations confirment l'augmentation des complications à SBHGA lors de la varicelle. Il paraît donc licite d'évoquer, de rechercher et de traiter une telle complication chez un enfant présentant une varicelle, dont la fièvre persiste de façon anormale et/ou chez lequel on observe des symptômes inhabituels associés à l'éruption.
Background. — An increase in the incidence of group A beta hemolytic streptococcal (GABHS) infections in children has been recently noted with a frequent association with varicella.
Case reports. — Two children, 3 and 4.5 years old, developed varicella. The first one was febrile and presented a phlyctene on his left foot. Few hours after his admission, he presented a septic shock; GABHS was isolated from blood. Despite immediate adapted antibiotherapy, he developped a right tibial osteomyelitis with abcess. The second child also developed varicella and was hospitalized because of fever, bad general condition, right cervical adenitis and edema on the left wrist. Edema rapidly extended to the hand and upper arm. One purulent lesion was noted on the upper arm from whom
Staphylococus aureus and GABHS were isolated. Blood samples were sterile. The clinical course was favorable with adapted antibiotherapy. A cutaneous desquamation was observed on the 9th day and we concluded that it was a GABHS cellulitis.
Conclusion. — These two cases confirm the recent report of increase in GABHS infections associated with varicella. Such complications must be looked for in patients with varicella remaining abnormaly febrile and/or presenting unusual manifestations.
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