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In eukaryotes, the cell has the ability to modulate the size of the nucleus depending on the surrounding environment, to enable nuclear functions such as DNA replication and transcription. From previous analyses of nuclear size scaling in various cell types and species, it has been found that eukaryotic cells have a conserved scaling rule, in which the nuclear size correlates with both cell size and genomic content. However, there are few studies that have focused on a certain cell type and systematically analyzed the size scaling properties in individual species (intra-species) and among species (inter-species), and thus, the difference in the scaling rules among cell types and species is not well understood. In the present study, we analyzed the size scaling relationship among three parameters, nuclear size, cell size, and genomic content, in our measured datasets of terminally differentiated erythrocytes of five Anura frogs and collected datasets of different species classes from published papers. In the datasets of isolated erythrocytes from individual frogs, we found a very weak correlation between the measured nuclear and cell cross-sectional areas. Within the erythrocytes of individual species, the correlation of the nuclear area with the cell area showed a very low hypoallometric relationship, in which the relative nuclear size decreased when the cell size increased. These scaling trends in intra-species erythrocytes are not comparable to the known general correlation in other cell types. When comparing parameters across species, the nuclear areas correlated with both cell areas and genomic contents among the five frogs and the collected datasets in each species class. However, the contribution of genomic content to nuclear size determination was smaller than that of the cell area in all species classes. In particular, the estimated degree of the contribution of genomic content was greater in the amphibian class than in other classes. Together with our imaging analysis of structural components in nuclear membranes, we hypothesized that the observed specific features in nuclear size scaling are achieved by the weak interaction of the chromatin with the nuclear membrane seen in frog erythrocytes.

Objective: This study was performed to evaluate the application of fetal middle cerebral artery peak systolic velocity (MCA-PSV) for prediction of newborn anemia with umbilical cord blood hemoglobin concentration at birth (UCB-Hb) 1.5 was defined as a positive MCA-PSV test result. Results: The MCA-PSV test was applied 2309 times (313 and 1996 times during second and third trimesters, respectively) in 699 women. The results were positive in 4.4% (102/2309) of tests and at least once in 9.9% (69/699) of women. Anemic infants were born to one (1.4%) and six (1.0%) of 69 and 630 women with and without at least one positive test result, respectively. MoM determined 4, 3, and 2 weeks before birth showed significant weak negative correlations with UCB-Hb at birth (correlation coefficient: 0.298–0.325). Conclusions: Among unselected women giving birth at or near term, the MCA-PSV test was unsatisfactory for prediction of newborn anemia in this retrospective observational study. Keywords: Antenatal care, Fetal echocardiography, Middle cerebral artery peak systolic velocity, Newborn anemia, Prenatal diagnosis

Objectives: To investigate the possibility of nephrinuria as a screening tool for the risk of pre-eclampsia (PE). Design: Prospective observational study. Setting: A single university hospital. Changes in urinary nephrin:creatinine ratio (NCR, ng/mg) and protein:creatinine ratio (PCR, mg/mg) in pregnancy were determined. Significant proteinuria in pregnancy (SPIP) was defined as PCR>0.27. PE was diagnosed in women with both SPIP and hypertension. Participants: 89 pregnant women in whom neither hypertension nor SPIP was present at enrolment, providing 31, 125 and 93 random urine samples during first, second and third trimesters, respectively. Results: PE developed in 14 of the 89 women. NCR increased with increasing PCR in 14 women with PE (correlation coefficient, 0.862; p<0.0001). In contrast, NCR did not change significantly despite significant increases in PCR in 75 women with normotensive pregnancies defined as neither SPIP nor hypertension, indicating that there was little increase in nephrinuria over the physiological range of proteinuria in pregnancy. Relative risk of later development of PE among asymptomatic second and third trimester women with NCR (ng/mg) >122 (95th centile value for 75 women with normotensive pregnancies) was 5.93 (95% CI 2.59 to 13.6; 60% (6/10) vs 10% (8/79)) and 13.5 (95% CI 3.31 to 55.0; 75% (6/8) vs 5.5% (2/36)), respectively, compared with women with NCR=122 at that time. Conclusions: Nephrinuria was unlikely to increase in normal pregnancy. A certain NCR cut-off may efficiently differentiate women at higher risk of PE. [ABSTRACT FROM AUTHOR]