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Background: Echocardiography and B-type natriuretic peptide (BNP) are diagnostic tests for congestive heart failure (CHF), but an emergency diagnosis can be difficult. Objective: To assess the diagnostic performance of BNP testing and echocardiographic assessment of left ventricular systolic function, separately and combined, for the identification of CHF in patients with acute dyspnea. Design: Prospective, multinational, multicenter study. Setting: Patients presenting to emergency departments in seven hospitals between June 1999 and December 2000. Patients: A total of 1,586 patients with acute dyspnea. Main Outcome Measures: Echocardiographic determination of ejection fraction (EF) and point-of care BNP measurement for the diagnosis of CHF. Results: Seven hundred nine of the 1,586 patients underwent echocardiography; 492 patients (69.4%) had a final diagnosis of CHF. Patients with CHF were older (68.5 years vs 61.6 years, p < 0.0001), had a lower EF (39.5% vs 56.1%, p < 0.0001), and a higher BNP (683 pg/mL vs 129 pg/mL, p < 0.0001) than patients without CHF. Area under the receiver operating characteristic (ROC) curve for the diagnosis of CHF was significantly higher for BNP (0.89) than for EF (0.78; area under the ROC curve difference, 0.12; p < 0.0001). The sensitivity of BNP > or = 100 pg/mL for the diagnosis of CHF was 89%, and specificity was 73%. Values for EF < or = 50% had a sensitivity of 70% and a specificity of 77%. Multivariate logistic regression analysis showed that, in combination with clinical, ECG, and chest radiograph data, BNP > or = 100 pg/mL and EF < or = 50% remained independent predictors of CHF (odds ratios, 32.1 and 6.2, respectively). The proportions of patients who were correctly classified were 67% for BNP alone, 55% for EF alone, 82% for the two variables together, and 97.3% when clinical, ECG, and chest radiograph data were added. Conclusion: BNP measurement was superior to two-dimensional echocardiographic determination of EF in identifying CHF, regardless of the threshold value. The two methods combined have marked additive diagnostic value. [ABSTRACT FROM AUTHOR]

In cyanobacteria, the D1 protein of photosystem II (PSII) is encoded by the psbA multigene family. In most freshwater strains, a D1:1 isoform of this protein is exchanged for a D1:2 isoform in response to various stresses, thereby altering PSII photochemistry. To investigate PSII responses to stress in marine Synechococcus, we acclimated cultures of the WH7803 strain to different growth irradiances and then exposed them to high light (HL) or ultraviolet (UV) radiation. Measurement of PSII quantum yield and quantitation of the D1 protein pool showed that HL-acclimated cells were more resistant to UV light than were low light- (LL) or medium light- (ML) acclimated cells. Both UV and HL induced the expression of psbA genes encoding D1:2 and the repression of the psbA gene encoding D1:1. Although three psbA genes encode identical D1:2 isoforms in Synechococcus sp. WH7803, only one was strongly stress responsive in our treatment conditions. Examination of 11 marine Synechococcus genomic sequences identified up to six psbA copies per genome, with always a single gene encoding D1:1. In phylogenetic analyses, marine Synechococcus genes encoding D1:1 clustered together, while the genes encoding D1:2 grouped by genome into subclusters. Moreover, examination of the genomic environment of psbA genes suggests that the D1:2 genes are hotspots for DNA recombination. Collectively, our observations suggest that while all psbA genes follow a concerted evolution within each genome, D1:2 coding genes are subject to intragenome homogenization most probably mediated by gene conversion.

The marine picocyanobacterium Synechococcus sp. WH8102 was submitted to ultraviolet (UV-A and B) radiations and the effects of this stress on reaction center II and phycobilisome integrity were studied using a combination of biochemical, biophysical and molecular biology techniques. Under the UV conditions that were applied (4.3 W m(-2) UV-A and 0.86 W m(-2) UV-B), no significant cell mortality and little chlorophyll degradation occurred during the 5 h time course experiment. However, pulse amplitude modulated (PAM) fluorimetry analyses revealed a rapid photoinactivation of reaction centers II. Indeed, a dramatic decrease of the D1 protein amount was observed, despite a large and rapid increase in the expression level of the psbA gene pool. Our results suggest that D1 protein degradation was accompanied (or followed) by the disruption of the N-terminal domain of the anchor linker polypeptide LCM, which in turn led to the disconnection of the phycobilisome complex from the thylakoid membrane. Furthermore, time course analyses of in vivo fluorescence emission spectra suggested a partial dismantling of phycobilisome rods. This was confirmed by characterization of isolated antenna complexes by SDS-PAGE and immunoblotting analyses which allowed us to locate the disruption site of the rods near the phycoerythrin I-phycoerythrin II junction. In addition, genes encoding phycobilisome components, including alpha-subunits of all phycobiliproteins and phycoerythrin linker polypeptides were all down regulated in response to UV stress. Phycobilisome alteration could be the consequence of direct UV-induced photodamages and/or the result of a protease-mediated process.

Objective: The purpose of this study was to build a nomogram of normal fetal lung volumes throughout gestational age estimated by 3-dimensional ultrasonography using the rotational technique (Virtual Organ Computer-Aided Analysis [VOCAL]; GE Healthcare, Kretztechnik, Zipf, Austria)., Methods: Fetal lung volume was assessed in 146 healthy fetuses by 3-dimensional ultrasonography using the technique of rotation of the multiplanar imaging (VOCAL). Inclusion criteria were healthy women with singleton normal pregnancies, normal fetal morphologic ultrasonographic findings, reliable dating established by dates and by ultrasonographic measurement of the crown-lump length in the first trimester, and gestational age from 20 to 37 weeks. Exclusion criteria were discordance between clinical and ultrasonographic dating, patients lost to follow-up, and birth weight disorders. Each patient was scanned once during pregnancy., Results: The right, left, and total mean pulmonary volumes ranged, respectively, from 5.37, 4.66, and 9.95 cm3 at 20 weeks to 46.06, 37.34, and 84.35 cm3 at 37 weeks. The logistic transformation analysis yielded the following formulas: right lung volume = exp(4.07/[1 + exp(21.90 - gestational age/5.44)]); left lung volume = exp(3.82/(1 + exp[22.03 - gestational age/5.17)]); and, total lung volume = exp(4.72/[1 + exp(20.30 - gestational age/6.05)])., Conclusions: A new nomogram of fetal lung (right, left, and total) volumes throughout gestational age using the rotational technique (VOCAL) is described, and reference values have been generated.

Objective: To evaluate the feasibility of prenatal power Doppler imaging of pulmonary arteries in congenital diaphragmatic hernia and to study its potential to predict outcome., Methods: A prospective observational study was conducted. Forty-two cases of congenital diaphragmatic hernia (32 left and 10 right) without associated anomalies were analyzed. Qualitative evaluation of pulmonary vasculature was based on power Doppler imaging performed at 26 to 38 weeks. The pulmonary arteries were studied in the lung contralateral to the hernia. Pulmonary Doppler angiography was considered satisfactory when 3 levels of bifurcation defining 3 distinct segments of the pulmonary arteries were imaged and was otherwise considered poor. We also recorded the gestational age at diagnosis, side of the hernia, abdominal circumference below the third percentile, amniotic fluid volume, lung/thoracic area ratio, left/right ventricle ratio, and, in left-sided hernias, stomach position, and we carried out a multivariate analysis to determine the contribution of each factor to predict neonatal mortality., Results: More than 3 divisions of the fetal pulmonary arteries were imaged in 20 cases; 1 or 2 divisions or none were imaged in 22. Neonatal mortality was significantly greater when fewer than 3 divisions of the pulmonary arteries were imaged (18 [82%] of 22) than when 3 divisions could be identified on power Doppler imaging (5 [25%] of 20; P = .0005). However, the lung/thoracic area ratio was the only factor that remained significantly associated with mortality in the multivariate analysis., Conclusions: An altered pulmonary power Doppler image is associated with neonatal mortality, but estimation of the lung area remains the best predictor of neonatal outcome.

Objective: To evaluate the potential of three-dimensional ultrasound to predict outcome in congenital diaphragmatic hernia., Design: Prospective observational study., Setting: Tertiary care centre., Population: Twelve cases of isolated congenital diaphragmatic hernia (11 left-sided, 1 right-sided) and 109 controls., Methods: Fetal lung volume was assessed by three-dimensional ultrasound using the technique of rotation of the multiplanar imaging. In the control fetuses, a logistic transformation was performed to correlate fetal lung volume with gestational age, and the confidence interval was obtained with a bootstrap resampling. A mathematical equation was then obtained allowing calculation of the expected fetal lung volume as a function of gestational age. In fetuses with congenital diaphragmatic hernia, the observed/expected lung volume ratio was compared with postnatal outcome., Main Outcome Measures: Neonatal mortality and pulmonary hypoplasia, which was defined as lung/body weight ratios less than 0.012., Results: The expected fetal lung volume was derived from the mathematical equation: Fetal lung volume (mL) = exp (4.72/(1 + exp ((20.32 - gestational age in weeks)/6.05))). The observed/expected fetal lung volume ratio was significantly lower in the congenital diaphragmatic hernia group (median: 0.34, range: 0.16-0.66), than in the control group (median: 1.02, range: 0.62-1.97, P < 0.0001). The distribution of this ratio was significantly downshifted in the infants with congenital diaphragmatic hernia who died (median: 0.19, range: 0.18-0.66) compared with survivors (median: 0.44, range: 0.36-0.66, P= 0.04). The observed/expected fetal lung volume ratio was also correlated with the postmortem lung/body weight ratio., Conclusion: In isolated congenital diaphragmatic hernia, fetal lung volume measurement by three-dimensional ultrasound is a potential predictor for pulmonary hypoplasia and postnatal outcome.

Objective: To assess the agreement of 3-dimensional ultrasonography and magnetic resonance imaging in estimating fetal lung volume in cases with isolated congenital diaphragmatic hernia., Methods: Fetal lung volume was measured in 11 cases of congenital diaphragmatic hernia (10 left and 1 right) by 3-dimensional ultrasonography and magnetic resonance imaging. These examinations were performed during the same week. The operators were blinded to each other's results. Intraclass correlation was used to evaluate the agreement between 3-dimensional ultrasonography and magnetic resonance imaging estimations of the ipsilateral, contralateral, and total fetal lung volume. A Bland-Altman graph was plotted to detect possible discordant observations., Results: The global intraclass correlation coefficient between magnetic resonance imaging and 3-dimensional ultrasonographic measurement of fetal lung volume was 0.94 (95% confidence interval, 0.78-0.98) with no outliers observed on the Bland-Altman plot., Conclusions: There is a good agreement between 3-dimensional ultrasonography and magnetic resonance imaging for fetal lung volume estimation in cases with congenital diaphragmatic hernia.