Specificity of Nuclear Size Scaling in Frog Erythrocytes.

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.

Fetal middle cerebral artery peak systolic velocity as a predictor of fetal anemia in unselected women giving birth at or near term.

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) < 10.0 g/dL among infants born at gestational week (GW) ≥ 36 to unselected women. MATERIALS AND METHODS: We reviewed the medical charts of 699 women giving birth to singleton infants at GW ≥ 36 with available data on MCA-PSV measured at GW ≥ 25 at the discretion of the attending physician. Multiple of the median (MoM) MCA-PSV (MCA-PSV MoM) > 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.

Liver dysfunction in women with pregnancy-induced antithrombin deficiency.

AIM: The aim of this study was to determine whether women with pregnancy-induced antithrombin deficiency (PIATD) had higher risk of liver dysfunction in the absence of thrombocytopenia. METHODS: We carried out a retrospective observational study at five centers in all 129 women with incidentally found PIATD among 5249 maternities and 129 control women without PIATD matched for number of fetuses and gestational week at delivery. PIATD was diagnosed in women with antenatal antithrombin (AT) activities of ≤75% followed by a further decrease to ≤65% peripartum. Liver dysfunction was defined as serum aspartate aminotransferase >  45 IU/L concomitant with lactate dehydrogenase >  400 IU/L. Thrombocytopenia was defined as platelet count < 120 × 109 /L. RESULTS: Thrombocytopenia (22% [28/129] vs 5.4% [7/129], P =  0.0001) and liver dysfunction (16% [20/129] vs 0.0% [0/129], P =  0.0000) occurred significantly more often in PIATD than in control women. Of the 20 women with liver dysfunction, 15 (75%) had PIATD, but not thrombocytopenia. Thus, even in the absence of thrombocytopenia, liver dysfunction occurred significantly more often in PIATD than in control women (15% [15/101] vs 0.0% [0/122], respectively, P =  0.0000). The relative risk (95% confidence interval) of liver dysfunction was 28.6 (1.64-500) for women with AT activity of 60-65% and 52.4 (3.17-865) for women with AT activity of <60%, compared to women with AT activity ≥66%. CONCLUSION: PIATD can occur in the absence of thrombocytopenia and PIATD women had higher risk of liver dysfunction even in the absence of thrombocytopenia.

Feasibility of nephrinuria as a screening tool for the risk of pre-eclampsia: prospective observational study.

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.

Isolated gestational proteinuria preceding the diagnosis of preeclampsia - an observational study.

INTRODUCTION: Some pregnant women develop significant proteinuria in the absence of hypertension. However, clinical significance of isolated gestational proteinuria (IGP) is not well understood. This study aimed to determine the prevalence of IGP in singleton pregnancies and the proportion of women with IGP who subsequently developed preeclampsia (IGP-PE) among all PE cases. MATERIAL AND METHODS: This was an observational study of 6819 women with singleton pregnancies at 12 centers, including 938 women with at least once determination of protein-to-creatinine ratio (P/Cr). Significant proteinuria in pregnancy (SPIP) was defined as P/Cr (mg/mg) level >0.27. IGP was defined as SPIP in the absence of hypertension. Gestational hypertension (GH) preceding preeclampsia (GH-PE) was defined as preeclampsia (PE) in which GH preceded SPIP. Simultaneous PE (S-PE) was defined as PE in which both SPIP and hypertension occurred simultaneously. RESULTS: IGP and PE were diagnosed in 130 (1.9%) and 158 (2.3%) of 6819 women, respectively. Of 130 women with IGP, 32 (25%) progressed to PE and accounted for 20% of all women with PE. Hence, women with IGP had a relative risk of 13.1 (95% CI; 9.2-18.5) for developing PE compared with those without IGP [25% (32/130) vs. 1.9% (126/6689)]. At diagnosis of SPIP, P/Cr levels already exceeded 1.0 more often in women with S-PE than in those with IGP-PE [67% (33/49) vs. 44% (14/32), respectively, p = 0.031]. CONCLUSIONS: IGP is a risk factor for PE, and IGP-PE accounts for a considerable proportion (20%) of all PE.

Isolated pregnancy-induced anti-thrombin deficiency in a woman with twin pregnancy.

A woman with twin pregnancy had a gradual decline in anti-thrombin (AT) activity from 72% at gestational week (GW) 29-3/7 , to 53% at GW31-2/7 , and to 41% at GW32-2/7 , at which time hypertension (148/90 mmHg) and proteinuria (protein-to-creatinine ratio [P/Cr], 0.79 mg/mg) developed in the presence of normal platelet count (159 × 109 /L) and serum aspartate aminotransferase/lactate dehydrogenase (22/164 IU/L). AT product was given three times to maintain AT activity >50% and blood pressure was maintained below 155/95 mmHg with no treatment, but generalized edema with a weekly weight gain of 4.9 kg and increased proteinuria (to P/Cr, 7.6 mg/mg) required cesarean section at GW33-3/7 . This case highlights the occurrence of pregnancy-induced AT deficiency alone in the absence of any other abnormality, including hypertension, proteinuria, or thrombocytopenia. Measurement of AT activity was considered helpful for determination of the appropriate time for delivery in this patient.

Urinary protein-to-creatinine ratio in pregnant women after dipstick testing: prospective observational study.

BACKGROUND: The dipstick test is widely used as a primary screening test for detection of significant proteinuria in pregnancy (SPIP). However, it often shows a false positive test result. This study was performed to determine which pregnant women should be recommended to undergo determination of urinary protein-to-creatinine ratio (mg/mg, P/Cr test) after dipstick test for confirmation of SPIP. METHODS: This was a multicenter, prospective, and observational study of 2212 urine specimens from 1033 pregnant women who underwent simultaneous dipstick and P/Cr tests in the same spot urine samples at least once. SPIP was defined as P/Cr > 0.27. Preeclampsia was diagnosed in women with both hypertension and SPIP. RESULTS: Preeclampsia, hypertension alone, and SPIP alone developed in 202 (20 %), 73 (7.1 %), and 120 (12 %) women, respectively. Creatinine concentration [Cr] varied greatly, ranging from 8.1 to 831 mg/dL in the 2212 urine samples. Rate of positive dipstick test results increased with increasing [Cr], while SPIP prevalence rate was lower in urine samples with higher [Cr], yielding higher false positive rates in samples with higher [Cr]. Postpartum urine samples had significantly lower [Cr] compared to those obtained antepartum (60 [8.7-297] vs. 100 [10-401] mg/dL, respectively). At the first P/Cr test among women with similar dipstick test results, the risk of having SPIP was consistently and significantly higher for hypertensive women than for normotensive women at any dipstick test result: 18 % (14/77) vs. 3.2 % (8/251), 47 % (26/55) vs. 8.7 % (37/425), 91 % (82/90) vs. 59 % (44/75) for negative/equivocal, 1+, and ≥ 2+ test results, respectively. The risk of SPIP was 16 % (9/55) for normotensive women when two successive antenatal urine samples showed a dipstick test result of 1 + . CONCLUSIONS: For prediction of SPIP, the dipstick test was more likely to show a false positive result in concentrated urine samples with higher [Cr]. Hypertensive women with ≥ 1+ as well as normotensive women with ≥ 2+ on dipstick test should be advised to undergo the P/Cr test.