Size structure of phytoplankton carbon and primary production in the Southern Ocean south of Australia during the summer of 1983-84

The size structure of phytoplankton carbon content and primary production were examined in the upper 125-m water column in the Southern Ocean south of Australia during the summer of 1983-84. At the surface, total phytoplankton carbon was 13.8±1.6μg/l in the Subantarctic Ocean and 45.6±27.4μg/l in the Antarctic Ocean. Phytoplankton in the 8 to 16-μm size class accounted for a large portion of phytoplankton carbon in the Subantarctic Ocean, whereas >64-μm forms were dominant in the Antarctic Ocean. The mean primary production was 0.952mgC/m^3/h in the Subantarctic Ocean and 0.400 in the Antarctic Ocean; the >20-μm fraction accounted for a major part of the total production in both areas. Geographically, both phytoplankton carbon and primary production in the small cell size classes (16 and >5μm, respectively) which were composed mainly of diatoms varied largely, determining the magnitude of the total values. Such large variation of biomass in netplankton as found in the surface water was also found down to the 125-m depth at all stations investigated. The importance of netplankton as primary producers in the Southern Ocean was discussed

Systemic neutrophil migration and rapid consumption of neutrophils in the spleen

The systemic migration of neutrophils is not fully understood. In this study, we purified neutrophils from rat peripheral blood and labeled them with [51Cr] sodium chromate. The labeled cells were injected into the tail veins of rats, and were traced. Neutrophils were rapidly trapped in the liver and the spleen within 6 h. The migration ratios of neutrophils in the lung and the gut were lower compared with those in the liver and the spleen. Interestingly, migrated cells into the spleen were rapidly phagocytosed by monocytes/macrophages. Therefore, accumulation of intact neutrophils in the spleen may be difficult to measure

National trends in the outcomes of subarachnoid haemorrhage and the prognostic influence of stroke centre capability in Japan: retrospective cohort study

Objectives To examine the national, 6-year trends in in-hospital clinical outcomes of patients with subarachnoid haemorrhage (SAH) who underwent clipping or coiling and the prognostic influence of temporal trends in the Comprehensive Stroke Center (CSC) capabilities on patient outcomes in Japan.Design Retrospective study.Setting Six hundred and thirty-one primary care institutions in Japan.Participants Forty-five thousand and eleven patients with SAH who were urgently hospitalised, identified using the J-ASPECT Diagnosis Procedure Combination database.Primary and secondary outcome measures Annual number of patients with SAH who remained untreated, or who received clipping or coiling, in-hospital mortality and poor functional outcomes (modified Rankin Scale: 3–6) at discharge. Each CSC was assessed using a validated scoring system (CSC score: 1–25 points).Results In the overall cohort, in-hospital mortality decreased (year for trend, OR (95% CI): 0.97 (0.96 to 0.99)), while the proportion of poor functional outcomes remained unchanged (1.00 (0.98 to 1.02)). The proportion of patients who underwent clipping gradually decreased from 46.6% to 38.5%, while that of those who received coiling and those left untreated gradually increased from 16.9% to 22.6% and 35.4% to 38%, respectively. In-hospital mortality of coiled (0.94 (0.89 to 0.98)) and untreated (0.93 (0.90 to 0.96)) patients decreased, whereas that of clipped patients remained stable. CSC score improvement was associated with increased use of coiling (per 1-point increase, 1.14 (1.08 to 1.20)) but not with short-term patient outcomes regardless of treatment modality.Conclusions The 6-year trends indicated lower in-hospital mortality for patients with SAH (attributable to better outcomes), increased use of coiling and multidisciplinary care for untreated patients. Further increasing CSC capabilities may improve overall outcomes, mainly by increasing the use of coiling. Additional studies are necessary to determine the effect of confounders such as aneurysm complexity on outcomes of clipped patients in the modern endovascular era