Interleukin-7 deficiency in rheumatoid arthritis: consequences for therapy-induced lymphopenia

We previously demonstrated prolonged, profound CD4⁺ T-lymphopenia in rheumatoid arthritis (RA) patients following lymphocyte-depleting therapy. Poor reconstitution could result either from reduced de novo T-cell production through the thymus or from poor peripheral expansion of residual T-cells. Interleukin-7 (IL-7) is known to stimulate the thymus to produce new T-cells and to allow circulating mature T-cells to expand, thereby playing a critical role in T-cell homeostasis. In the present study we demonstrated reduced levels of circulating IL-7 in a cross-section of RA patients. IL-7 production by bone marrow stromal cell cultures was also compromised in RA. To investigate whether such an IL-7 deficiency could account for the prolonged lymphopenia observed in RA following therapeutic lymphodepletion, we compared RA patients and patients with solid cancers treated with high-dose chemotherapy and autologous progenitor cell rescue. Chemotherapy rendered all patients similarly lymphopenic, but this was sustained in RA patients at 12 months, as compared with the reconstitution that occurred in cancer patients by 3–4 months. Both cohorts produced naïve T-cells containing T-cell receptor excision circles. The main distinguishing feature between the groups was a failure to expand peripheral T-cells in RA, particularly memory cells during the first 3 months after treatment. Most importantly, there was no increase in serum IL-7 levels in RA, as compared with a fourfold rise in non-RA control individuals at the time of lymphopenia. Our data therefore suggest that RA patients are relatively IL-7 deficient and that this deficiency is likely to be an important contributing factor to poor early T-cell reconstitution in RA following therapeutic lymphodepletion. Furthermore, in RA patients with stable, well controlled disease, IL-7 levels were positively correlated with the T-cell receptor excision circle content of CD4⁺ T-cells, demonstrating a direct effect of IL-7 on thymic activity in this cohort.     

Randomised controlled trial assessing the impact of a nurse delivered,flow monitored protocol for optimisation of circulatory status after cardiac surgery

Objective To assess whether a nurse led, flow monitored protocol for optimising circulatory status in patients after cardiac surgery reduces complications and shortens stay in intensive care and hospital.Design Randomised controlled trial.Setting Intensive care unit and cardiothoracic unit of a university teaching hospital.Participants 174 patients who underwent cardiac surgery between April 2000 and January 2003.Interventions Patients were allocated to conventional haemodynamic management or to an algorithm guided by oesophageal Doppler flowmetry to maintain a stroke index above 35 ml/m².Results 26 control patients had postoperative complications (two deaths) compared with 17 (four deaths) protocol patients (P = 0.08). Duration of hospital stay in the protocol group was significantly reduced from a median of nine (interquartile range 7-12) days to seven (7-10) days (P = 0.02). The mean duration of hospital stay was reduced from 13.9 to 11.4 days, a saving in hospital bed days of 18% (95% confidence interval -12% to 47%). Usage of intensive care beds was reduced by 23% (-8% to 59%).Conclusion A nurse delivered protocol for optimising circulatory status in the early postoperative period after cardiac surgery may significantly shorten hospital stay.     

Delivering interventions for depression by using the internet: randomised controlled trial

Objective To evaluate the efficacy of two internet interventions for community-dwelling individuals with symptoms of depression—a psychoeducation website offering information about depression and an interactive website offering cognitive behaviour therapy.Design Randomised controlled trial.Setting Internet users in the community, in Canberra, Australia.Participants 525 individuals with increased depressive symptoms recruited by survey and randomly allocated to a website offering information about depression (n = 166) or a cognitive behaviour therapy website (n = 182), or a control intervention using an attention placebo (n = 178).Main outcome measures Change in depression, dysfunctional thoughts; knowledge of medical, psychological, and lifestyle treatments; and knowledge of cognitive behaviour therapy.Results Intention to treat analyses indicated that information about depression and interventions that used cognitive behaviour therapy and were delivered via the internet were more effective than a credible control intervention in reducing symptoms of depression in a community sample. For the intervention that delivered cognitive behaviour therapy the reduction in score on the depression scale of the Center for Epidemiologic Studies was 3.2 (95% confidence interval 0.9 to 5.4). For the “depression literacy” site (BluePages), the reduction was 3.0 (95% confidence interval 0.6 to 5.2). Cognitive behaviour therapy (MoodGYM) reduced dysfunctional thinking and increased knowledge of cognitive behaviour therapy. Depression literacy (BluePages) significantly improved participants'' understanding of effective evidence based treatments for depression (P < 0.05).Conclusions Both cognitive behaviour therapy and psychoeducation delivered via the internet are effective in reducing symptoms of depression.     

Total RNA isolation from<Emphasis Type="Italic">Picea mariana</Emphasis> dry seed

Isolating RNA from dry conifer seeds can be difficult because of a number of interfering compounds present in seeds. We describe a protocol for total RNA isolation from black spruce dry seeds, which is an adaptation of a method used for mouse myeloma tissues. The extraction relies on selective precipitation of RNA by using lithium chloride.     

Resistance of Solid-Phase U(VI) to Microbial Reduction during In Situ Bioremediation of Uranium-Contaminated Groundwater

Speciation of solid-phase uranium in uranium-contaminated subsurface sediments undergoing uranium bioremediation demonstrated that although microbial reduction of soluble U(VI) readily immobilized uranium as U(IV), a substantial portion of the U(VI) in the aquifer was strongly associated with the sediments and was not microbially reducible. These results have important implications for in situ uranium bioremediation strategies.     

Alterations in osteoclast morphology following long-term 17beta-estradiol administration in the mouse

Background  

Although the role of the osteoclast in bone resorption is becoming better understood, much remains to be learned about osteoclastogenesis and the exact mechanism of action of anti-resorbing agents such as 17β-estradiol. This study investigated bone and morphologic osteoclast alterations following long-term estrogen administration to the B6D2F1 mouse. B6D2F1 mice aged 4-5 weeks were exposed to high levels of estrogen via implanted silastic tubing for at least 12 weeks; controls received empty tubing. Femurs of control and treated mice were assessed with radiology, quantitative histomorphometry and transmission electron microscopy.     

In Vacuo Esterification of Carboxyl Groups in Lyophilized Proteins

A new method is described for the esterification of carboxyl groups in proteins by reaction of the lyophilized protein in vacuo with gaseous alcohol and HCI catalyst. Carboxyl groups are rapidly esterified with no protein degradation. 13C-Methyl or 13C-ethyl esters of the alpha-, gamma- and delta-carboxyl groups could be distinguished by the distinct chemical shifts of their resonances. Within the class of gamma- or delta-esters, the chemical shifts have little variation; however, the chemical shift of a C-terminal esterified alpha-carboxyl group shows a strong dependence on the nature of the C-terminal amino acid and sequence. Iodomethane reacts with deprotonated carboxyl groups in lyophilized proteins to form methyl esters, but unlike the reaction with gaseous methanol/HCI, it does not selectively methylate carboxyl groups. The procedure permits the cost-effective incorporation of isotopic labels and provides a new approach using 13C-NMR spectroscopy for determining the number of different C-termini present in a protein preparation.     

The role of zooplankton grazing in the formation of `clear water phase' in a shallow charophyte-dominated lake

In Chara-dominated shallow eutrophic Lake Prossa (Estonia), the collapse of spring phytoplankton community occurred in late May after which both primary production (PP) and phytoplankton biomass (B&pinf;) stayed at a very low level. By mid-June the Secchi depth had increased up to 2.6 m indicating the achievement of the `clear water phase', which persisted thoughout the rest of the vegetation period. The biomass of `edible' phytoplankton formed on average 53% of the total phytoplankton biomass, and the share of herbivorous zooplankton was on average 61% of the total zooplankton biomass. In spring zooplankton removed daily 27% of the total B&pinf; and 29% of PP by grazing while in summer these values rarely exceeded 5%. Zooplankton grazing was responsible for the decrease of `edible' (<31 μm) phytoplankton after its spring peak as well as for maintaining its biomass at a very low level during the whole vegetation period. Depletion of mineral forms of nitrogen and phosphorus that occurred most probably because of the development of charophytes by the end of May supported the collapse of the whole phytoplankton community and kept the water clear throughout the summer and autumn.