Nanoscale structural and electronic properties of cellulose/graphene interfaces.

The development of electronic devices based on the functionalization of (nano)cellulose platforms relies upon an atomistic understanding of the structural and electronic properties of a combined system, cellulose/functional element. In this work, we present a theoretical study of the nanocellulose/graphene interfaces (nCL/G) based on first-principles calculations. We find that the binding energies of both hydrophobic/G (nCLphob/G) and hydrophilic/G (nCLphil/G) interfaces are primarily dictated by the van der Waals interactions, and are comparable with those of their 2D interface counterparts. We verify that the energetic preference of nCLphob/G has been reinforced by the inclusion of an aqueous medium via an implicit solvation model. Further structural characterization was carried out using a set of simulations of the carbon K-edge X-ray absorption spectra to identify and distinguish the key absorption features of the nCLphob/G and nCLphil/G interfaces. The electronic structure calculations reveal that the linear energy bands of graphene lie in the band gap of the nCL sheet, while depletion/accumulation charge density regions are observed. We show that external agents, i.e., electric field and mechanical strain, allow for tunability of the Dirac cone and charge density at the interface. The control/maintenance of the Dirac cone states in nCL/G is an important feature for the development of electronic devices based on cellulosic platforms.

A multi-objective optimization approach accurately resolves protein domain architectures.

MOTIVATION: Given a protein sequence and a number of potential domains matching it, what are the domain content and the most likely domain architecture for the sequence? This problem is of fundamental importance in protein annotation, constituting one of the main steps of all predictive annotation strategies. On the other hand, when potential domains are several and in conflict because of overlapping domain boundaries, finding a solution for the problem might become difficult. An accurate prediction of the domain architecture of a multi-domain protein provides important information for function prediction, comparative genomics and molecular evolution. RESULTS: We developed DAMA (Domain Annotation by a Multi-objective Approach), a novel approach that identifies architectures through a multi-objective optimization algorithm combining scores of domain matches, previously observed multi-domain co-occurrence and domain overlapping. DAMA has been validated on a known benchmark dataset based on CATH structural domain assignments and on the set of Plasmodium falciparum proteins. When compared with existing tools on both datasets, it outperforms all of them. AVAILABILITY AND IMPLEMENTATION: DAMA software is implemented in C++ and the source code can be found at http://www.lcqb.upmc.fr/DAMA. CONTACT: juliana.silva_bernardes@upmc.fr or alessandra.carbone@lip6.fr SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Heterosis in hybrids within and between yeast species.

The performance of hybrids relative to their parents is an important factor in speciation research. We measured the growth of 46 Saccharomyces yeast F1 interspecific and intraspecific hybrids, relative to the growth of each of their parents, in pairwise competition assays. We found that the growth of a hybrid relative to the average of its parents, a measure of mid-parent heterosis, correlated with the difference in parental growth relative to their hybrid, a measure of phenotypic divergence, which is consistent with simple complementation of low fitness alleles in one parent by high fitness alleles in the other. Interspecific hybrids showed stronger heterosis than intraspecific hybrids. To manipulate parental phenotypic divergence independently of genotype, we also measured the competitive growth of a single interspecific hybrid relative to its parents in 12 different environments. In these assays, we not only identified a strong relationship between parental phenotypic divergence and mid-parent heterosis as before, but, more tentatively, a weak relationship between phenotypic divergence and best-parent heterosis, suggesting that complementation of deleterious mutations was not the sole cause of interspecific heterosis. Our results show that mating between different species can be beneficial, and demonstrate that competition assays between parents and offspring are a useful way to study the evolutionary consequences of hybridization.

Impact of the introduction of fetal central monitoring on hospital expenses with cardiotocographic paper.

Digital storage of cardiotocographic (CTG) tracings by fetal central monitoring systems (fCMS) obviates the need for printing, or alternatively, the tracings can be printed in regular paper instead of CTG thermal paper. We aimed at evaluating the impact of the introduction of the Omniview-SisPorto(®) system on CTG paper costs in a large university hospital. After introduction of the fCMS, there was an 87% reduction in median annual expenses with CTG paper in the labour ward (p = 0.011) and a 78% decrease in the prenatal clinic (p = 0.017), despite a more than 40% increase in the median number of observed women. Routine use of fCMS may provide an important reduction in hospital expenses associated with the use of thermal CTG paper, thus reducing the investment made in their acquisition and maintenance.

Knowledge of adverse neonatal outcome alters clinicians' interpretation of the intrapartum cardiotocograph.

OBJECTIVE: To evaluate the impact of knowledge of neonatal outcome on clinicians' interpretation of the intrapartum cardiotocograph (CTG). DESIGN: Prospective evaluation of pre-recorded cases. SETTING: Five maternity hospitals. POPULATION: From a database of intrapartum CTGs acquired with a scalp electrode in singleton near-term fetuses, 20 tracings were sequentially selected from cases with newborn umbilical artery pH < 7.05 and 20 from cases with pH > 7.20. METHODS: Five experienced obstetricians practising in different maternity hospitals were asked to analyse the 40 tracings individually, according to the International Federation of Gynaecology and Obstetrics guidelines. In a first round, clinicians were given no information on neonatal outcome. In a second round, carried out 2 months later, clinicians were asked to analyse the same tracings, but the order was randomly altered and information on the newborn's arterial pH was provided. Clinicians were not informed of the purpose of the study or whether the tracings were the same. MAIN OUTCOME MEASURES: The incidence of individual fetal heart rate feature identification and tracing classification, before and after neonatal outcome was made available. RESULTS: In the group with pH < 7.05, repetitive decelerations and reduced variability were more common in the second round (P < 0.001 and P = 0.001, respectively), as was a pathological classification (P = 0.002); variable decelerations were less common (P = 0.008). In the group with normal pH, less tracings in the second round had prolonged decelerations (P = 0.013) and no accelerations (P = 0.013), but more had pronounced decelerations (P = 0.031) and reduced variability (P = 0.007); there was a reduction in pathological classifications, but this difference failed to reach statistical significance (P = 0.051). CONCLUSIONS: A knowledge of adverse neonatal outcome leads to a more severe classification of the intrapartum CTG, which derives mainly from the evaluation of decelerations and variability.

Access to computerised analysis of intrapartum cardiotocographs improves clinicians' prediction of newborn umbilical artery blood pH.

OBJECTIVE: To evaluate the impact of access to computerised cardiotocograph (CTG) analysis on reproducibility and accuracy of clinicians' predictions of umbilical artery blood pH (UAB pH) and 5-minute Apgar score. DESIGN: Prospective evaluation of pre-recorded cases. SETTING: A tertiary-care university hospital. POPULATION: From databases of intrapartum CTGs acquired in singleton term pregnancies, 204 tracings with low signal loss and short time interval to delivery were consecutively selected. METHODS: Tracings were randomly assigned to computer analysis by the Omniview-SisPorto 3.5 system (study group n = 104) or to no analysis (control group n = 100). Three experienced clinicians evaluated all tracing printouts independently and were asked to predict the newborns' UAB pH and 5-minute Apgar scores from them. MAIN OUTCOME MEASURES: Interobserver agreement (measured by the intraclass correlation coefficient [ICC]) and accuracy in prediction of neonatal outcomes with 95% CI. RESULTS: Agreement on prediction of UAB pH was significantly higher in the study group (ICC = 0.70; 95% CI 0.61-0.77) than in the control group (ICC = 0.43; 95% CI 0.21-0.60), and a trend towards better agreement was also seen in estimation of 5-minute Apgar scores (ICC = 0.55; 95% CI 0.38-0.68 versus ICC = 0.43; 95% CI 0.25-0.57). Observers predicted UAB pH values correctly within a 0.10 margin in 70% of cases in the study group (95% CI 0.61-0.79) versus 46% in the control group (95% CI 0.35-0.56). They predicted 5-minute Apgar scores within a margin of one in 81% of cases in the study group (95% CI 0.73-0.88) and in 70% of cases in the control group (95% CI 0.61-0.79). CONCLUSIONS: Prediction of UAB pH is more reproducible and accurate when clinicians have access to computerised analysis of CTGs.

Case report: intra-partum utero-ovarian vessels rupture.

CASE: We report the rare case of a 39-year-old woman who had an intra-partum hemoperitoneum that resulted from spontaneous rupture of the utero-ovarian vessels. During the expulsive efforts, the patient repeatedly complained of bilateral shoulder discomfort and some respiratory difficulty. Because she had hemodynamic instability and an abdomino-pelvic ultrasound revealed the presence of extensive free fluid within the peritoneal cavity, the patient underwent an exploratory laparotomy. The surgery revealed an extensive laceration of the anterior leaf of the left broad ligament and vesico-uterine peritoneum, and active bleeding from the utero-ovarian vessels with no evidence of uterine rupture. CONCLUSION: Intra-partum haemoperitoneum resulting from rupture of the utero-ovarian vessels is a rare obstetrical emergency that needs rapid resuscitation with fluid and/or blood replacement and prompt surgical intervention.

Chitosan nanoparticles for nitric oxide delivery in human skin.

The use of nanoparticle-based transdermal delivery systems is a promising approach to efficiently carry and deliver therapeutic agents for dermal and systemic administration. Nitric oxide (NO) is a key molecule that plays important roles in human skin such as the control of skin homeostasis, skin defense, control of dermal blood flow, and wound healing. In addition, human skin contains stores of NO derivatives that can be mobilized and release free NO upon UV irradiation with beneficial cardiovascular effects, for instance the control of blood pressure. In this work, the NO donor precursor glutathione (GSH) was encapsulated (encapsulation efficiency of 99.60%) into ultra-small chitosan nanoparticles (CS NPs) (hydrodynamic size of 30.65 ± 11.90 nm). GSH-CS NPs have a core-shell structure, as revealed by atomic force microscopy and X-ray photoelectron spectroscopy, in which GSH is protected in the nanoparticle core. Nitrosation of GSH by nitrous acid led to the formation of the NO donor S-nitrosogluthathione (GSNO) into CS NPs. The GSNO release from the CS NPs followed a Fickian diffusion described by the Higuchi mathematical model. Topical application of GSNO-CS NPs in intact human skin significantly increased the levels of NO and its derivatives in the epidermis, as assayed by confocal microscopy, and this effect was further enhanced by skin irradiation with UV light. Therefore, NO-releasing CS NPs are suitable materials for transdermal NO delivery to local and/or systemic therapies.

Neurological damage arising from intrapartum hypoxia/acidosis.

Complications occurring at any level of foetal oxygen supply will result in hypoxaemia, and this may ultimately lead to hypoxia/acidosis and neurological damage. Hypoxic-ischaemic encephalopathy (HIE) is the short-term neurological dysfunction caused by intrapartum hypoxia/acidosis, and this diagnosis requires the presence of a number of findings, including the confirmation of newborn metabolic acidosis, low Apgar scores, early imaging evidence of cerebral oedema and the appearance of clinical signs of neurological dysfunction in the first 48 h of life. Cerebral palsy (CP) consists of a heterogeneous group of nonprogressive movement and posture disorders, frequently accompanied by cognitive and sensory impairments, epilepsy, nutritional deficiencies and secondary musculoskeletal lesions. Although CP is the most common long-term neurological complication associated with intrapartum hypoxia/acidosis, >80% of cases are caused by other phenomena. Data on minor long-term neurological deficits are scarce, but they suggest that less serious intellectual and motor impairments may result from intrapartum hypoxia/acidosis. This chapter focuses on the existing evidence of neurological damage associated with poor foetal oxygenation during labour.

Livedoid vasculopathy - a challenging disease.

We present a rare association of idiopathic livedoid vasculopathy (LV) with peripheral sensory neuropathy successfully treated with intravenous immunoglobulin and warfarin and, after its failure, with rituximab. Although LV aetiology remains incompletely understood, the excellent clinical response observed in our patient suggests that B cells may be key players in its pathogenesis.

Antepartum fetal cerebral hemorrhage not predicted by current surveillance methods in cholestasis of pregnancy.

BACKGROUND: The reason for increased fetal mortality in cholestasis of pregnancy is not completely understood. Intracerebral hemorrhage due to coagulation disorders, similar to those reported in the mother, is a possible explanation. CASE: Antepartum fetal death occurred at 37 weeks in a primigravida with cholestasis of pregnancy. The woman was taking no medication. Autopsy revealed extensive cerebral hemorrhage. A cardiotocogram and biophysical profile performed 24 hours and 5 days, respectively, before fetal death had been normal. CONCLUSION: Antepartum fetal death may occur in patients with mild cholestasis who are taking no medication. Intracerebral hemorrhage is a possible cause, and this may be unpredictable with current methods of fetal surveillance. This possibility constitutes an argument in support of delivering these pregnancies as soon as lung maturity is achieved.

An interactive web site for research on fetal heart rate monitoring.

BACKGROUND: Traditional methods of exchange of research information may not be rapid enough, especially for international multicenter studies or when discussing controversial issues such as the value of fetal monitoring. The Internet is a useful tool that provides numerous opportunities for immediate communication within a large and diverse community of researchers. METHOD: A Web site at http://www.sisporto.med.up.pt was developed for a multicenter research project with interlinked pages on automated fetal heart rate (FHR) monitoring. It includes background knowledge about the subject, detailed information about the project, and a few interactive pages. These pages allow online discussions, simulations of data analysis, and download of data for local FHR analysis. EXPERIENCE: The Web site has been accessed from all over the world. In particular, participating research centers have had easy and fast access to background project information, and a few other clinicians and researchers participated in our online discussions and used the simulation tools or the data provided for analysis of typical FHR patterns. CONCLUSION: Web sites can be useful in multicenter research projects and for scientific information exchange.

Translocation (1;5)(q32;q35) in CD30+ anaplastic large cell non-Hodgkin lymphona of childhood. A case report.

The authors studied cytogenetically a case of CD30+ anaplastic large cell non-Hodgkin lymphoma previously diagnosed as malignant histiocytosis and detected a translocation involving chromosomes 1 and 5, t(1;5)(q32:q35). After comparing their findings with those from reports in the literature, they comment about the importance of breakpoint q35 on chromosome 5 and point out the importance of associating morphologic, immunoperoxidase, and cytogenetic findings to confirm the diagnosis of this tumor.

Semiautomated ultrasonographic measurement of fetal nuchal translucency using a computer software tool.

Nuchal translucency (NT) thickness measurement has been recently proposed as a part of routine ultrasound scanning during the late first trimester of pregnancy, for the early screening of chromosomal abnormalities. Manual determination of NT is currently performed using electronic calipers placed by the operator in the middle of two echogenic lines displayed on the screen. Therefore, intraobserver and interobserver repeatability can be questioned. This paper presents a software tool that has been developed for achieving this goal in a semiautomatic way, improving the reproducibility of the method.

Fetal heart-rate monitoring during maternal hypoglycaemic coma: a case report.

Contradictory descriptions exist concerning the fetal heart-rate (FHR) patterns that appear during maternal hypoglycaemia. We report a case of maternal hypoglycaemic coma during which a FHR tracing was obtained showing a normal type D accelerative pattern.

Monitoring of cardiac-extracardiac haemodynamics and automated fetal heart rate preceding intrauterine death.

A severely growth-retarded fetus was monitored longitudinally for haemodynamic profiles and automated cardiotocogram analysis in the 30 days preceding death. Initially a pattern of hypoxia and moderately deteriorated cardiac function was detected. Later on, signs of progressive heart failure developed, in conjunction with deteriorating fetal heart rate patterns.

Evaluation of interobserver agreement of cardiotocograms.

OBJECTIVE: To evaluate interobserver agreement in visual analysis of each cardiotocographic event. METHODS: Three experts independently divided 16 antepartum and 17 intrapartum cardiotocograms into baseline segments, accelerations and decelerations, according to the FIGO guidelines. Baseline segments were further classified as having normal, reduced or increased variability and decelerations as early, late and variable. Uterine activity was divided into tonus and contractions. Agreement was assessed by the proportions of agreement (pa) with 95% confidence intervals. RESULTS: Reproducibility in assessment of baseline segments with normal variability, accelerations and uterine activity was acceptable (pa = 0.56-0.71) whereas that of other segments was not (pa = 0.14-0.45). CONCLUSIONS: Analysis of most cardiotocographic events is poorly reproducible, even when experts use the FIGO guidelines. This may be explained by some still ambiguous guidelines, by eyeball limitations in evaluation of subtle events, and by the incapacity of busy clinicians to assess complex and multiple cardiotocographic events in a systematic and disciplined fashion.

Objective computerized fetal heart rate analysis.

OBJECTIVE: To assess the validity of a computerized methodology for cardiotocogram analysis based on a recently described reproducible visual estimation of the baseline. METHODS: Forty-two antepartum and 43 intrapartum cardiotocograms (CTGs) acquired by a personal computer were selected. Antepartum tracings were performed in the 48 h that preceded an elective cesarean section, and intrapartum tracings were performed until delivery. FHR baselines were estimated by an expert, according to an objective and reproducible methodology. Using these baselines, automated detection of accelerations and decelerations and estimation of variability was performed by the personal computer. A quantitative adaptation of the FIGO guidelines for fetal monitoring was used to classify tracings. Perinatal outcome was classified according to the Apgar score and umbilical arterial pH. Validity was then assessed by the proportions of agreement (PA), kappa statistic (K), sensitivity and specificity, with 95% confidence intervals (95% CI). Cases showing a disagreement between CTG and perinatal classification were reviewed and an adjustment in baseline definition was tested. RESULTS: The initial overall PA and kappa between CTG and perinatal classification were, respectively, 0.79 (95% CI: 0.69-0.87) and 0.62 (95% CI: 0.41-0.83). The overall PA and K, after baseline adjustment were, respectively, 0.89 (95% CI: 0.81-0.95) and 0.78 (95% CI: 0.58-0.98). Sensitivities and specificities ranged between 79% (95% CI: 60-92%) and 100% (95% CI: 95-100%). CONCLUSIONS: Good clinical prediction may be possible with an objective methodology for cardiotocogram analysis based on a recently described reproducible baseline estimation.