Local diagnostic reference levels for paediatric non-cardiac interventional radiology procedures

PurposeTo establish local diagnostic reference levels (DRLs) for non-cardiac interventional procedures in paediatrics.MethodsThe type of procedure, the patient’s weight and age and dose-related data from 279 interventions was recorded in a database completed by interventional radiologists, radiographers and technicians of the Medical Physics department. These procedures were classified into 14 categories and 6 weight ranges. Local DRLs were proposed for those ranges in which a sample of at least 15 patients could be gathered and were calculated as the third quartile (Q3) of the air kerma-area product (P_KA) values. The Q3 of the fluoroscopy time (FT) and number of digital subtraction angiography (DSA) images were also obtained. Finally, the correlation between P_KA and weight was analysed.ResultsLocal DRLs are proposed for three types of procedures: hepatic/biliary interventions (5–15 kg, 1304 cGy·cm²; 15–30 kg, 2121 cGy·cm²), sclerotherapy procedures (15–30 kg, 704 cGy·cm²; 30–50 kg, 4049 cGy·cm²; 50–80 kg, 3734 cGy·cm²) and central venous catheter (CVC) procedures (5–15 kg, 84 cGy·cm²). Hepatic/biliary interventions showed a moderate correlation (r = 0.61), while sclerotherapy procedures presented a poor correlation (r = 0.34) between P_KA and weight, possibly due to the P_KA dependence on the complexity level. Regarding CVC procedures, a clearly higher correlation was found when the fluoroscopy P_KA value was normalised to the FT (r = 0.85 vs r = 0.35).ConclusionsThe results support the feasibility of establishing DRLs for the most common procedures (sclerotherapy, hepatic/biliary and CVC interventions) despite the small number of paediatric interventions.     

Growth and adaptation to phototrophic conditions of Rhodospirillum rubrum and Rhodopseudomonas sphaeroides at different temperatures

The influence of temperature on yields of cell protein and bacteriochlorophyll as well as on the rates of growth and bacteriochlorophyll synthesis was studied with Rhodospirillum rubrum and Rhodopseudomonas sphaeroides. Under chemotrophic conditions net cell-protein production increased in cultures of both species along with temperature from 14°C up to the optimum at 33°C. Under phototrophic conditions cell-protein yields were largely constant within the range from 21°C to 33°C. At temperatures below 21°C and above 33°C yields decreased. These results are interpreted in terms of coupling between energy yielding or redox equivalent providing metabolisms and cell biosynthesis. Upon adaptation from chemotrophic to phototrophic conditions a direct relationship between temperature increase and bacteriochlorophyll level was observed. Arrhenius plots of both, specific growth rates and rates of bacteriochlorophyll synthesis, revealed discontinuities at about 20°C. Temperature coefficients either above or below those discontinuities were similar in both species. In R. rubrum temperature coefficients of the synthesis of total bacteriochlorophyll were also representative of the synthesis of photochemical reaction center and light harvesting bacteriochlorophylls. But in R. sphaeroides significant differences were observed between temperature coefficients of the syntheses of bacteriochlorophylls of the costantly composed reaction centerlight harvesting complex on one hand and of both, total and the quantitatively variable light harvesting bacteriochlorophylls on the other. The results are interpreted in light of hypotheses on the regulation (a) of cellular bacteriochlorophyll levels as well as (b) of the ratio of functionally different bacteriochlorophylls in the photosynthetic apparatus.Abbreviation Bchl bacteriochlorophyll     

Functional genotypes are associated with commensal Escherichia coli strain abundance within‐host individuals and populations

The selective pressures that determine genotype abundance and distribution frequently vary between ecological levels. Thus, it is often unclear whether the same functional genotypes will become abundant at different levels and how selection acting at these different scales is linked. In this study, we examined whether particular functional genotypes, defined by the presence or absence of 34 genes, of commensal Escherichia coli strains were associated with within‐host abundance and/or host population abundance in a wild population of 54 adult mountain brushtail possums (Trichosurus cunninghami). Our results revealed that there was a positive correlation between a strain's relative abundance within individuals and the strain's abundance in the host population. We also found that strain abundance at both ecological levels was predicted by the same group of functional genes (agn43, focH, micH47, iroN, ygiL, ompT, kspmT2 and K1) that had associated patterns of occurrence. We propose that direct selection on the same functional genes at both levels may in part be responsible for the observed correlation between the ecological levels. However, a potential link between abundance within the host and excretion rate may also contribute.     

The effect of selected basic dyes on the blood cells,in particular,the basophils,of the Pacific oyster,Crassostrea gigas

It was determined by means of light and electron microscopy that the granular blood cells of Pacific oysters could absorb basic dyes from dye-coated plastic beads injected into the mantles of oysters; in doing so, the granular blood cells became altered morphologically and behaviorally. In addition, it was observed that oysters could absorb the basic dye, toluidine blue O, in low concentration from sea water. It was shown that the absorption of toluidine blue O caused a shift in the blood cell levels of oysters, and it was suggested that this shift was occasioned by the absorption of toluidine blue O by granulocytes.     

Opportunities to advance the synthesis of ecology and evolution

Despite decades of research on the interactions between ecology and evolution, opportunities still remain to further integrate the two disciplines, especially when considering multispecies systems. Here, we discuss two such opportunities. First, the traditional emphasis on the distinction between evolutionary and ecological processes should be further relaxed as it is particularly unhelpful in the study of microbial communities, where the very notion of species is hard to define. Second, key processes of evolutionary theory such as adaptation should be exported to hierarchical levels higher than populations to make sense of biodiversity dynamics. Together, we argue that broadening our perspective of eco-evolutionary dynamics to be more inclusive of all biodiversity, both phylogenetically and hierarchically, will open up fertile new research directions and help us to address one of the major scientific challenges of our time, that is, to understand and predict changes in biodiversity in the face of rapid environmental change.     

成人脂肪肝与体重指数和血脂水平的关系研究

目的:研究成人脂肪肝与体重指数(BMI)和血脂水平的关系。方法:选取2012年1月到2014年11月我社区成年人800例,检测所有入选者的体重和身高,并计算BMI,检测入选者的血脂水平和脂肪肝情况,应用Logistic回归分析来分析脂肪肝与BMI和血脂之间的关系。结果:共检测出脂肪肝376例,占47.0%,肥胖者532例,占66.5%;肥胖者伴随脂肪肝的发生率64.7%,显著高于非肥胖者脂肪肝的发生率11.9%,两者比较差异具有统计学意义(P0.05);脂肪肝者总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)显著高于非脂肪肝者,而高密度脂蛋白(HDL-C)显著低于非脂肪肝者,两者比较差异具有统计学意义(P0.05);Logistic回归分析显示:脂肪肝与BMI和血脂之间存在相关关系(P0.05)。结论:BMI和血脂水平与成人脂肪肝存在较大关系,应该注意控制体重,进而降低脂肪肝的发生率,改善脂肪肝的情况。     

Evaluation of the level of anthropogenic transformation of vegetative cover in mountainous areas

A technique for the evaluation of anthropogenic transformation of vegetative cover at the local, subregional, and regional levels is considered. It includes compilation of phytoecological maps based on the revealed spatial and temporal nonuniformity of vegetative cover and analysis of its relationship with the environment.     

Studies on osmotic balance and its control in the freshwater mollusc parreysia corrugata

Percent increase in body weight of 48 hours cerebralactomized mussels in tap water was significantly higher than in control mussels. 48 hours cerebralactomized mussels, injected with cerebral ganglia homogenate, restored their body weight to the normal level in tap water. 48 hours cerebralactomized mussels injected with saline solution did not show any significant increase in weight.The aminoacid levels were studied by introducing the mussels in different salinities. There was an increase in the amino acid content as the percent salinity increased. Thus it may be inferred that osmotic balance in Parreysia corrugata is controlled both by cerebral neurosecretion and by amino acid levels.     

Plasmodium chabaudi: relationship between the occurrence of recrudescent parasitaemias in mice and the effective levels of acquired immunity

In NIH inbred mice infected with the $\text{A}\text{S}$ strain of Plasmodium chabaudi the erythrocytic infection shows an acute primary parasitaemia which becomes subpatent after about 2 weeks. A period (7–10 days) of subpatency follows before a short-lasting patent recrudescence appears. The appearance of the recrudescent parasitaemia was examined in relation to (1) the level of antiplasmodial antibody detected by the indirect fluorescent antibody (IFA) test, (2) the antiparasite activity of the serum measured by the passive protection test, and (3) the ability of the mice to control and eliminate a large intravenous challenge infection. In the period between the primary parasitaemia becoming subpatent and the onset of the recrudescence there was a slight drop in the IFA levels, and a steep decline in passive protective levels and in the ability of the mice to control a large intravenous challenge infection. It is suggested that a decline in the effector arm in the immune response contributes to emergence of the recrudescent parasitaemias.     

Students’ conceptions of the carbon cycle: identifying and interrelating components of the carbon cycle and tracing carbon atoms across the levels of biological organisation

This study investigates students’ conceptions of the carbon cycle with regard to the components they believe to be relevant to the carbon cycle, how they interrelate these components, the ways in which they trace carbon atoms, and the different levels of biological organisation they consider when doing so. A total of 142 students aged 13–16 years (grades 8–10) participated in the study. A total of 130 students completed the diagnostic task, and an additional 12 students completed both the diagnostic task and were interviewed. The primary results show that the students identified few components of the carbon cycle, tended to trace carbon atoms exclusively at the level of the organism, and had difficulties identifying organic carbon compounds, especially during processes in which carbon compounds are transformed. Considering the main educational implications, we recommend using an instructional strategy that traces carbon atoms across the different levels of biological organisation whilst connecting fragmented knowledge by integrating knowledge from physiology, biochemistry and ecology when teaching the carbon cycle.