Combined impacts of future land-use and climate stressors on water resources and quality in groundwater and surface waterbodies of the upper Thames river basin, UK.

It is widely acknowledged that waterbodies are becoming increasingly affected by a wide range of drivers of change arising from human activity. To illustrate how this can be quantified a linked modelling approach was applied in the Thames river basin in southern UK. Changes to river flows, water temperature, river and reservoir quality were predicted under three contrasting future "storylines"; one an extension of present day rates of economic development, the others representing more extreme and less sustainable visions. Modelling revealed that lower baseflow conditions will arise under all storylines. For the less extreme storyline river water quality is likely to deteriorate but reservoir quality will improve slightly. The two more extreme futures could not be supported by current management strategies to meet water demand. To satisfy these scenarios, transfer of river water from outside the Thames river basin would be necessary. Consequently, some improvement over present day water quality in the river may be seen, and for most indicators conditions would be better than in the less extreme storyline. However, because phosphorus concentrations will rise, the invoked changes in water demand management would not be of a form suitable to prevent a marked deterioration in reservoir water quality.

Identifying multiple stressor controls on phytoplankton dynamics in the River Thames (UK) using high-frequency water quality data.

River phytoplankton blooms can pose a serious risk to water quality and the structure and function of aquatic ecosystems. Developing a greater understanding of the physical and chemical controls on the timing, magnitude and duration of blooms is essential for the effective management of phytoplankton development. Five years of weekly water quality monitoring data along the River Thames, southern England were combined with hourly chlorophyll concentration (a proxy for phytoplankton biomass), flow, temperature and daily sunlight data from the mid-Thames. Weekly chlorophyll data was of insufficient temporal resolution to identify the causes of short term variations in phytoplankton biomass. However, hourly chlorophyll data enabled identification of thresholds in water temperature (between 9 and 19°C) and flow (<30m(3)s(-1)) that explained the development of phytoplankton populations. Analysis showed that periods of high phytoplankton biomass and growth rate only occurred when these flow and temperature conditions were within these thresholds, and coincided with periods of long sunshine duration, indicating multiple stressor controls. Nutrient concentrations appeared to have no impact on the timing or magnitude of phytoplankton bloom development, but severe depletion of dissolved phosphorus and silicon during periods of high phytoplankton biomass may have contributed to some bloom collapses through nutrient limitation. This study indicates that for nutrient enriched rivers such as the Thames, manipulating residence time (through removing impoundments) and light/temperature (by increasing riparian tree shading) may offer more realistic solutions than reducing phosphorus concentrations for controlling excessive phytoplankton biomass.

Emergency physicians accumulate more stress factors than other physicians-results from the French SESMAT study.

INTRODUCTION: France is facing a shortage of available physicians due to a greying population and the lack of a proportional increase in the formation of doctors. Emergency physicians are the medical system's first line of defence. METHODS: The authors prepared a comprehensive questionnaire using established scales measuring various aspects of working conditions, satisfaction and health of salaried physicians and pharmacists. It was made available online, and the two major associations of emergency physicians promoted its use. 3196 physicians filled out the questionnaire. Among them were 538 emergency physicians. To avoid bias, 1924 physicians were randomly selected from the total database to match the demographic characteristics of France's physician population: 42.5% women, 57.5% men, 8.2% < 35 years old, 33.8% 35-44 years old, 34.5% 45-54 years old and 23.6% ≥ 55 years old. The distribution of physicians in the 23 administrative regions and by speciality was also precisely taken into account. This representative sample was used to compare subgroups of physicians by speciality. RESULTS: The outcomes indicate that the intent to leave the profession (ITL) was quite prevalent across French physicians and even more so among emergency physicians (17.4% and 21.4% respectively), and burnout was highly prevalent (42.4% and 51.5%, respectively). Among the representative sample and among emergency physicians, work-family conflict (OR=4.47 and OR=6.14, respectively) and quality of teamwork (OR=2.21 and OR=5.44, respectively) were associated with burnout in a multivariate analysis, and these risk factors were more prevalent among emergency physicians than other types. A serious lack of quality of teamwork appears to be associated with a higher risk of ITL (OR=3.92 among the physicians in the representative sample and OR=4.35 among emergency physicians), and burnout doubled the risk of ITL in multivariate analysis. CONCLUSIONS: In order to prevent the premature departure of French doctors, it is important to improve work-family balance, working processes through collaboration, multidisciplinary teamwork and to develop team training approaches and ward design to facilitate teamwork.

NUDC expression during amphibian development.

To identify gene products important for gastrulation in the amphibian Pleurodeles waltl, a screen for regional differences in new protein expression at the early gastrula stage was performed. A 45 kDa protein whose synthesis was specific for progenitor endodermal cells was identified. Microsequencing and cDNA cloning showed that P45 is highly homologous to rat NUDC, a protein suggested to play a role in nuclear migration. Although PNUDC can be detected in all regions of the embryo, its de novo synthesis is tightly regulated spatially and temporally throughout oogenesis and embryonic development. New PNUDC synthesis in the progenitor endodermal cells depends on induction by the mesodermal cells in the gastrula. During development, PNUDC is localized in the egg cortical cytoplasm, at the cleavage furrow during the first embryonic division, around the nuclei and cortical regions of bottle cells in the gastrula, and at the basal region of polarized tissues in the developing embryo. These results show for the first time the expression and compartmentalization of PNUDC at distinct stages during amphibian development.

Cell-cycle-dependent nuclear translocation of HSP70 in amphibian embryonic cells.

Using immunocytochemical methods, we analyzed the localization of the HSP70 protein constitutively expressed during embryogenesis in the amphibian Pleurodeles waltl. Our results provide evidence for nuclear transfer of the protein during gastrulation, and particularly for predominant nuclear labeling in gastrula internalized cells. Using two inhibitors of DNA replication -hydroxyurea (HUA) and aphidicolin- or/and an inhibitor of transcription -actinomycin D- applied to embryos, we demonstrated that nuclear transfer of HSP70 is related to the transcriptional activity of the cells during the early S phase of the cell cycle.

Conditions for a heat shock response during oogenesis and embryogenesis of the amphibian Pleurodeles waltl.

The optimal conditions capable of inducing an increase in HSP70 neosynthesis during development of the urodele amphibian Pleurodeles waltl were determined in this study. These conditions depend on temperature, heat shock duration and recovery duration. In oocytes, a heat shock response was repeatedly obtained at 37 degrees C for 15 min followed by 1 h recovery. These results provided evidence for heat shock response at every stage considered. An increase in HSP70 synthesis was noted throughout oogenesis, but it did not lead to an increase in the amount of soluble HSP70, except for stage VI oocytes. Such results suggest that from stage II to stage IV oocytes, an equilibrium occurs between the HSP70 used and the HSP70 neosynthesized. In contrast, in stage VI oocytes, heat shock led to overproduction of HSP70. During early development, the heat shock response was repeatedly obtained only from the gastrula stage with a 37 degrees C shock and a 15 min duration of treatment. Surprisingly, during cleavage stage, the soluble HSP70 total amount increased after heat shock at a time when no HSP70 neosynthesis occurred.

Benefit of active compression-decompression cardiopulmonary resuscitation as a prehospital advanced cardiac life support. A randomized multicenter study.

BACKGROUND: We compared short-term prognosis of active compression-decompression (ACD) and standard (STD) cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrests. METHODS AND RESULTS: We randomized advanced cardiac life support (ACLS) with ACD ACLS CPR on odd days and STD ACLS CPR on even days. We measured the rates of return of spontaneous circulation (ROSC), survival at 1 hour (H1), at 24 hours (H24), and at 1 month (D30): hospital discharge (HD); neurological outcome; and complications. Mean times from collapse to basic cardiac life support CPR was 9 minutes and from collapse to ACLS CPR was 21 minutes. Compared with the STD ACLS patients (n = 258), ACD ACLS patients (n = 254) had higher survival rates (ROSC, 44.9% versus 29.8%, P = .0004; H1, 36.6% versus 24.8%, P = .003; H24, 26% versus 13.6%, P = .002; HD without neurological impairment, 5.5% versus 1.9%, P = .03) and a trend for improvement in neurological outcome at D30 (Glasgow-Pittsburgh Outcome Categories = 1.6 +/- 0.8 versus 2.3 +/- 1.1. P = .09). Sternal dislodgements (2.9% versus 0.4%, P = .03) and hemoptysis (5.4% versus 1.3%, P = .01) were more frequent in the ACD ACLS group. CONCLUSIONS: Despite long time intervals, ACD significantly improved short-term survival rates in out-of-hospital cardiac arrests compared with STD CPR.

Does the chaperone heat shock protein hsp70 play a role in the control of developmental processes?

Expression of an hsp70 gene strictly inducible in somatic cells and constitutively expressed during oogenesis was investigated during embryogenesis of the amphibian Pleurodeles waltl. Results from Northern hybridization experiments and RNase protection assays provided evidence for the presence of inducible hsp70 mRNA under normal conditions at every embryonic stage. Immunoblotting of embryo proteins separated by 2D-electrophoresis provided evidence for the presence of a single polypeptide of about 74 kDa likely to be an HSP70-related protein, from unfertilized egg to tailbud stage. Immunocytological analysis showed that HSP70-related proteins were localized in the cytoplasm of all blastomeres. It also pointed out that nuclear transfer of the protein occurs in certain cells, precisely at the time of their invagination and subsequent internalization during normal Pleurodeles development. Such nuclear transfer involves involuting mesodermal cells in the blastopore region at the time of gastrulation. It also involves neurodermic cells at the time of neural tube closure. Interestingly, in exogastrulas nuclear transfer did not occur in cells which could no longer invaginate. Such behavior of HSP70-related proteins led us to suggest that they are involved in the control of nuclear activity associated with important developmental events such as cellular internalization processes. Such a role may be a direct consequence of HSP70-related protein functional properties as molecular chaperones.

c-mpl expression in hematologic disorders.

The c-mpl gene encodes a member of the hematopoietic cytokine receptor superfamily. This gene was discovered through the study of a murine retrovirus which induces an acute myeloproliferative syndrome in mice. MPLV (for myeloproliferative leukemia virus) has transduced a truncated and constitutively activated form of the c-mpl receptor chain. The c-mpl ligand is unknown, but recent data indicate that it could specifically regulate thrombocytopoiesis. This review focuses on the expression of the c-mpl gene in a large series of human hematopoietic pathologies by Northern blot analysis. Barely detectable transcript levels were detected in normal bone marrow (BM) and in BM samples from chronic myeloproliferative disorders, plasmocytoma, Burkitt lymphoma or acute lymphoid leukemia. In contrast, high levels of c-mpl expression were detected in 45% of acute myeloid leukemia (AML). No correlation was found between c-mpl expression and the French-American-British classification subtype of AML. However c-mpl expression correlated with CD34 expression, and unfavorable cytogenetic abnormalities, defining a subgroup of AML with a low rate of complete remission. In myelodysplasia, c-mpl expression was elevated in 44% of chronic myelomonocytic leukemia (CMML), 42% of refractory anemia with excess myeloblasts (RAEB), and RAEB in transformation to acute leukemia (RAEBt), but not in refractory anemia (RA) and RA with ringed sideroblasts (RARS). In CMML, there was no correlation between c-mpl expression and any prognostic factor tested, nor with the course of the disease. The biologic significance of c-mpl expression in RAEB and RAEBt is probably different.(ABSTRACT TRUNCATED AT 250 WORDS)

The determination of thiamin pyrophosphate in blood and other tissues, and its correlation with erythrocyte transketolase activity.

A sensitive method for the specific measurement of thiamin pyrophosphate (TPP) has been developed using the apoenzyme recombination concept. Yeast pyruvic decarboxylase apoenzyme can be reconstituted by the addition of TPP or samples containing TPP, yielding the holoenzyme with activity proportionate to the amount of TPP added. Using this technique, reaction mixtures containing 0.2 to 1.5 ng TPP can be assayed. Normal human erythrocyte TPP ranges from 50 to 150 ng per ml packed cells. When rats are fed a thiamin deficient diet, the erythrocyte TPP level falls more rapidly than the erythrocyte transketolase activity. After 8 days, the level of TPP in the erythrocytes of deficient animals was 10% of the level in pair-fed controls. At this time, however, there was no appreciable decrease in their respective transketolase activities. The level of TPP in the liver also is decreased drastically after 8 days. Therefore it appears that erytyrocyte and liver TPP stores have begun to be depleted and suggest that erythrocyte TPP levels are a more sensitive indicator of thiamin status.