Summary
The development of efficient probiotic application protocols for use in marine larviculture relies on comprehensive understanding of pathogen–probiont–host interactions. The probiont ...combination of Pseudoalteromonas sp. PP107 and Vibrio sp. PP05 provides additive protection against vectored Vibrio owensii DY05 infection in larvae (phyllosomas) of ornate spiny lobster, Panulirus ornatus. Here, fluorescently tagged strains were used to demonstrate niche specialization of these probionts in both the live feed vector organism Artemia and in phyllosomas. The pathogen was vulnerable to direct interaction with PP05 in the bacterioplankton as well as in the Artemia gut and the phyllosoma foregut and midgut gland. In contrast, PP107 was localized on external surfaces of Artemia and phyllosomas, and direct interaction with the pathogen was limited to the bacterioplankton. While PP107 was the overall dominant ectobiont on the phyllosoma cephalothorax and inner leg segments, PP05 was the primary colonizer of outer leg segments, nutrient‐rich locales that may promote ingestion during feeding. This study shows that niche specialization can contribute to the additive probiotic effect of a probiotic mixture and highlights that probiotic enrichment of Artemia cultures can intercept the infection cycle of V. owensii DY05 in early‐stage P. ornatus phyllosomas.
Net uptake of carbon dioxide (CO2) measured by eddy covariance in a 60- to 80-year-old forest averaged 2.0 ± 0.4 megagrams of carbon per hectare per year during 1993 to 2000, with interannual ...variations exceeding 50%. Biometry indicated storage of 1.6 ± 0.4 megagrams of carbon per hectare per year over 8 years, 60% in live biomass and the balance in coarse woody debris and soils, confirming eddy-covariance results. Weather and seasonal climate (e.g., variations in growing-season length or cloudiness) regulated seasonal and interannual fluctuations of carbon uptake. Legacies of prior disturbance and management, especially stand age and composition, controlled carbon uptake on the decadal time scale, implying that eastern forests could be managed for sequestration of carbon.
Net uptake of carbon dioxide (CO
2
) measured by eddy covariance in a 60- to 80-year-old forest averaged 2.0 ± 0.4 megagrams of carbon per hectare per year during 1993 to 2000, with interannual ...variations exceeding 50%. Biometry indicated storage of 1.6 ± 0.4 megagrams of carbon per hectare per year over 8 years, 60% in live biomass and the balance in coarse woody debris and soils, confirming eddy-covariance results. Weather and seasonal climate (e.g., variations in growing-season length or cloudiness) regulated seasonal and interannual fluctuations of carbon uptake. Legacies of prior disturbance and management, especially stand age and composition, controlled carbon uptake on the decadal time scale, implying that eastern forests could be managed for sequestration of carbon.
Net uptake of carbon dioxide (CO.sub.2) measured by eddy covariance in a 60- to 80-year-old forest averaged 2.0 + or - 0.4 megagrams of carbon per hectare per year during 1993 to 2000, with ...interannual variations exceeding 50%. Biometry indicated storage of 1.6 + o r - 0.4 megagrams of carbon per hectare per year over 8 years, 60% in rive biomass and the batance in coarse woody debris and soils, confirming eddy-covariance results. Weather and seasonal climate (e.g., variations in growing-season length or cloudiness) regulated seasonal and interannual fluctuations of carbon uptake. Legacies of prior disturbance and management, especially stand age and composition, controlled carbon uptake on the decadal time scale, implying that eastern forests could be managed for sequestration of carbon.
Continuous measurements of whole canopy isoprene emissions over an entire growing season are reported from Harvard Forest (42 degree 32 theta N, 72 degree 11 theta W). Emissions were calculated from ...the ratio of observed CO sub(2) flux and gradient multiplied by the observed hydrocarbon gradients. In summer 1995, 24-hour average emissions of isoprene from June 1 through October 31 were 32.7 x 10 super(10) molecules cm super(-2) s super(-1) (mg C m super(-2) h super(-1) = 2.8 x 10 super(11) molecules cm super(-2) s super(-1)), and the mean midday mixing ratio was 4.4 ppbv at 24 m. Isoprene emissions were zero at night, increased through the morning with increasing air temperature and light, reached a peak in the afternoon between the peaks in air temperature and light, and then declined with light. Isoprene emissions were observed over a shorter seasonal period than photosynthetic carbon uptake. The normalized emission rate remained constant for approximately 65 days, then decreased steadily through September and into October. Measured isoprene emissions were higher than the Biogenic Emission Inventory System-II model by at least 40% at midday and showed distinctly different diurnal and seasonal emission patterns. Seasonal adjustment factors (in addition to the light and temperature factors) should be incorporated into future empirical models of isoprene emissions.
We have analysed the behaviour of minimal residual disease (MRD) after allogeneic bone marrow transplantation (allo-BMT) in 71 children with acute lymphoblastic leukaemia (ALL). The method relied on ...PCR of IgH, TCRdelta and/or TCRgamma gene rearrangements followed by electrophoretic size resolution and allele-specific oligoprobing. Patients were similarly conditioned; 55 received marrow from unrelated donors and 16 from related donors. MRD was assessed at various time-points up to 24 months after BMT. Three children were not evaluable due to transplant-related mortality. MRD was detected in 28/32 patients (88%) who relapsed post-BMT; 16 were positive at all times and 12 were initially negative but became positive at a median of 3 months (range 1.5-11) prior to relapse. In contrast, only eight of 36 (22%) patients who remained in continuing complete remission (CCR) (median follow-up 43 months, range 20-94) showed MRD at any time after BMT (P<0.0001). In these eight patients MRD was found up to 9 months after transplant and at low levels (0.01-0.001%). All eight (median follow-up 39 months, range 24-87) had at least two MRD-negative samples tested subsequently and five of the eight had evidence of grade I-II acute graft-versus-host disease (GvHD), raising the possibility of a graft-versus-leukaemia effect. In general, any evidence of MRD after allo-BMT is a poor prognostic sign. However, if immunotherapy were to be targeted towards patients with evidence of persisting MRD after BMT, the method described would expose only a small proportion of patients to unnecessary additional toxicity.
Vibrio owensii DY05 is a serious pathogen causing epizootics in the larviculture of ornate spiny lobster Panulirus ornatus. In the present study a multi-tiered probiotic screening strategy was used ...to identify a probiotic combination capable of protecting P. ornatus larvae (phyllosomas) from experimental V. owensii DY05 infection. From a pool of more than 500 marine bacterial isolates, 91 showed definitive in vitro antagonistic activity towards the pathogen. Antagonistic candidates were shortlisted based on phylogeny, strength of antagonistic activity, and isolate origin. Miniaturized assays used a green fluorescent protein labelled transconjugant of V. owensii DY05 to assess pathogen growth and biofilm formation in the presence of shortlisted candidates. This approach enabled rapid processing and selection of candidates to be tested in a phyllosoma infection model. When used in combination, strains Vibrio sp. PP05 and Pseudoalteromonas sp. PP107 significantly and reproducibly protected P. ornatus phyllosomas during vectored challenge with V. owensii DY05, with survival not differing significantly from unchallenged controls. The present study has shown the value of multispecies probiotic treatment and demonstrated that natural microbial communities associated with wild phyllosomas and zooplankton prey support antagonistic bacteria capable of in vivo suppression of a pathogen causing epizootics in phyllosoma culture systems.
A strategy for the solid phase synthesis of
18Flabelled peptides has been developed. The peptides were prepared on solid support and acylated with 4-
18Ffluorobenzoic acid using HATU within 3 min ...and the labelled peptide was released from the solid support within 7 min. The
18Flabelled peptides were produced in good purity with a specific activity of 20–25 GBq/μmol.
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