ABSTRACT
OBJECTIVE: To assess the predictive accuracy of the sFlt-1/PlGF ratio cut-off 38 in addition to the standard-of-care spot urine protein/creatinine ratio (PCr) for multiple pregnancies in women with suspected pre-eclampsia. STUDY DESIGN: Post-hoc analysis of a prospective cohort study. MAIN OUTCOME MEASURES: Primary outcome was the occurrence of pre-eclampsia in one and four weeks after presentation with suspected pre-eclampsia. Test characteristics with 95% confidence intervals (CI) were calculated on pre-eclampsia development in one and four weeks. RESULTS: Twenty-three multiple pregnancies with suspected pre-eclampsia between 20 and 37 weeks gestation were included for analysis. Women who eventually developed pre-eclampsia had a significantly higher PCr (34.0 vs. 16.5, p = 0.015), sFlt-1 (17033 vs. 5270 pg/ml, p = 0.047) and sFlt-1/PlGF ratio (99 vs. 25, p = 0.033) at baseline. Furthermore, PCr ≥ 30 and sFlt-1/PlGF ratio > 38 was respectively seen in 1/16 (6.3 %) and 3/16 (18.8 %) of the women who did not develop pre-eclampsia. For predicting pre-eclampsia within one week the sFlt-1/PlGF ratio sensitivity was 75.0 % [95 % CI 19.4-99.4] and the negative predictive value 93.8 % [73.0-98.8], while no pre-eclampsia developed when PCr was < 30. Consequently, the combination of these tests did not lead to an improvement in test characteristics, with non-significant differences in positive predictive value (50.0 % [29.5-70.5] versus 80.0 % [37.3-96.4]) compared to PCr alone for pre-eclampsia development in one week. CONCLUSIONS: In addition to standard-of-care spot urine PCr measurements, this study has not been able to demonstrate that the sFlt-1/PlGF ratio cut-off 38 is of added value in the prediction of pre-eclampsia in multiple pregnancy. TRIAL REGISTRATION: Netherlands Trial Register (NL8308).
Subject(s)
Biomarkers , Creatinine , Placenta Growth Factor , Pre-Eclampsia , Predictive Value of Tests , Vascular Endothelial Growth Factor Receptor-1 , Humans , Female , Pregnancy , Pre-Eclampsia/urine , Pre-Eclampsia/diagnosis , Pre-Eclampsia/blood , Vascular Endothelial Growth Factor Receptor-1/blood , Adult , Biomarkers/urine , Biomarkers/blood , Placenta Growth Factor/blood , Placenta Growth Factor/urine , Creatinine/urine , Creatinine/blood , Prospective Studies , Proteinuria/urineABSTRACT
BACKGROUND: This study investigated the clinical value of adding the sFlt-1/PlGF ratio to the spot urine protein/creatinine ratio (PCr) in women with suspected pre-eclampsia. METHODS: This was a prospective cohort study performed in a tertiary referral centre. Based on the combination of PCr (< 30) and sFlt-1/PlGF (≤38) results, four groups were described: a double negative result, group A-/-; a negative PCr and positive sFlt-1/PlGF, group B-/+; a positive PCr and negative sFlt-1/PlGF, group C+/-; and a double positive result, group D+/+. The primary outcome was the proportion of false negatives of the combined tests in comparison with PCr alone in the first week after baseline. Secondary, a cost analysis comparing the costs and savings of adding the sFlt-1/PlGF ratio was performed for different follow-up scenarios. RESULTS: A total of 199 women were included. Pre-eclampsia in the first week was observed in 2 women (2%) in group A-/-, 12 (26%) in group B-/+, 4 (27%) in group C+/-, and 12 (92%) in group D+/+. The proportion of false negatives of 8.2% [95% CI 4.9-13.3] with the PCr alone was significantly reduced to 1.6% [0.4-5.7] by adding a negative sFlt-1/PlGF ratio. Furthermore, the addition of the sFlt-1/PlGF ratio to the spot urine PCr, with telemonitoring of women at risk, could result in a reduction of 41% admissions and 36% outpatient visits, leading to a cost reduction of 46,- per patient. CONCLUSIONS: Implementation of the sFlt-1/PlGF ratio in addition to the spot urine PCr, may lead to improved selection of women at low risk and a reduction of hospital care for women with suspected pre-eclampsia. TRIAL REGISTRATION: Netherlands Trial Register (NL8308).
Subject(s)
Pre-Eclampsia , Female , Humans , Pre-Eclampsia/diagnosis , Cohort Studies , Prospective Studies , Netherlands , Costs and Cost AnalysisABSTRACT
Therapeutic plasma exchange (TPE) is indicated as a treatment for a wide array of diseases, extensively addressed in the Guidelines of the American Society for Apheresis. In pregnancy, TPE is an uncommon event and application is largely based on extrapolation of efficacy and safety in a non-pregnant population. This review intends to describe the currently available experience of TPE in pregnancy to help clinicians recognise indications during pregnancy and to support current guideline recommendations with literature-based experiences. In order to identify the clinical indications for which TPE is applied in pregnant women, we performed a literature search including studies till November 2019, without a start date restriction. Data extraction included medical indication for TPE and safety of TPE in pregnant women. 279 studies were included for analysis. Nowadays, TPE is predominantly applied for thrombotic microangiopathies, lipid disorders and a variety of autoimmune diseases. The application of TPE during pregnancy remains largely empiric and relies on individual case reports in the absence of high-quality studies and definitive evidence-based guidelines. Safety profile of TPE during pregnancy appears to be comparable to application of TPE in non-pregnant patients. In conclusion, based on the limited evidence that we found in literature with a high risk of publication bias, TPE procedures can be used safely during pregnancy with the appropriate preparation and experience of a multidisciplinary team.
Subject(s)
Autoimmune Diseases , Blood Component Removal , Thrombotic Microangiopathies , Autoimmune Diseases/therapy , Female , Humans , Plasma Exchange , Pregnancy , Retrospective StudiesABSTRACT
OBJECTIVE: Daily use of inhaled corticosteroids (ICS) reduces exercise induced bronchoconstriction (EIB) in asthmatic children. A high single dose of ICS also provided acute protection against EIB. Objective of this study is to investigate whether a low single dose of ICS offers protection against EIB in asthmatic children. METHODS: 31 Mild asthmatic children not currently treated with inhaled corticosteroids, 5-16 years, with EIB (fall in FEV0.5/1 ≥ 13%) were included in a prospective intervention study. They performed two ECT's within 2 weeks. Four hours before the second test children inhaled 200 µg beclomethasone-dipropionate (BDP) with a breath-actuated inhaler (BAI). RESULTS: The median fall in FEV0.5/1 after 200 µg BDP was significantly reduced from 30.9% at baseline to 16.0% (P < 0.001). Twenty children (64.5%) showed a good response to 200 µg BDP (≥ 50% decrease in fall of FEV0.5/1), while 8 children showed a moderate response (25-50%), and three children showed no response at all (< 25%). CONCLUSION: A low single dose ICS offers acute protection against EIB in the majority of asthmatic children not currently treated with inhaled corticosteroids.
Subject(s)
Asthma, Exercise-Induced/prevention & control , Beclomethasone/administration & dosage , Glucocorticoids/administration & dosage , Adolescent , Child , Child, Preschool , Dose-Response Relationship, Drug , Female , Forced Expiratory Volume , Humans , Male , Nebulizers and Vaporizers , Prospective StudiesABSTRACT
Using protons for the treatment of ocular melanoma (especially of posterior pole tumours), the radiation quality of the beam must be precisely assessed to preserve the vision and to minimise the damage to healthy tissue. The radiation quality of a therapeutic proton beam at the Centre Antoine Lacassagne in Nice (France) was measured using microdosimetric techniques, i.e. a miniaturised version of a tissue-equivalent proportional counter. Measurements were performed in a 1-µm site at different depths in a Lucite phantom. Experimental data showed a significant increase in the beam quality at the distal edge of the spread-out Bragg peak (SOBP). In this paper, the numerical simulation of the experimental setup is done with the FLUKA Monte Carlo radiation transport code. The calculated microdosimetric spectra are compared with the measured ones at different depths in tissue for a monoenergetic proton beam (E=62 MeV) and for a modulated SOBP. Numerically and experimentally predicted relative biological effectiveness values are in good agreement. The calculated frequency-averaged and dose-averaged lineal energy mean values are consistent with measured data.
Subject(s)
Eye Neoplasms/physiopathology , Eye Neoplasms/radiotherapy , Melanoma/physiopathology , Melanoma/radiotherapy , Models, Biological , Radiotherapy, Computer-Assisted/methods , Radiotherapy, Conformal/methods , Computer Simulation , Humans , Proton Therapy , Treatment OutcomeABSTRACT
OBJECTIVE: To investigate potential personal, social and physical environmental predictors of daily fruit intake and daily vegetable intake in 11-year-old boys and girls in nine European countries. SUBJECTS: The total sample size was 13 305 (90.4% participation rate). RESULTS: Overall, 43.2% of the children reported to eat fruit every day, 46.1% reported to eat vegetables every day. Daily fruit intake and daily vegetable intake was mainly associated with knowledge of the national recommendations, positive self-efficacy, positive liking and preference, parental modeling and demand and bringing fruit to school (odds ratio between 1.40 and 2.42, P<0.02). These factors were associated fairly consistently with daily fruit intake across all nine European countries, implying that a rather uniform intervention strategy to promote fruit can be used across Europe. For vegetables, the pattern was, however, less consistent. Differences between countries in cooking and preparing vegetables might be responsible for this larger diversity. CONCLUSIONS: This study showed that especially a combination of personal and social factors is related to daily fruit and vegetable intake in schoolchildren. This shows that a comprehensive multilevel intervention strategy based upon a series of individual and social correlates will be most promising in the promotion of daily fruit and vegetable intake in children.
Subject(s)
Child Nutritional Physiological Phenomena/physiology , Diet , Fruit , Self Efficacy , Vegetables , Attitude to Health , Child , Cross-Cultural Comparison , Cross-Sectional Studies , Diet/psychology , Diet/trends , Europe , Feeding Behavior/psychology , Female , Food Preferences/psychology , Health Knowledge, Attitudes, Practice , Health Promotion/methods , Humans , Male , Nutrition Surveys , Parent-Child Relations , Predictive Value of Tests , Surveys and QuestionnairesABSTRACT
The purpose was to investigate the degree of implementation and appreciation of a comprehensive school-randomized fruit and vegetable intervention program and to what extent these factors were associated with changes in reported fruit and vegetable intake. The study was conducted among 10- to 13-year old children exposed to the intervention during the school year 2003-04 in Norway, Spain and the Netherlands. Children, parents and teachers completed questionnaires regarding (i) the implementation of the school curriculum, (ii) parental involvement, (iii) distribution of fruit and vegetables at school, (iv) children's appreciation of the project and (v) children's intake levels. Univariate analyses of covariance and multilevel multivariate regression analyses indicated that teacher-reported level of implementation of the school curriculum and schoolchildren's appreciation of the project were important determinants of changes in intake. The results point to the importance of optimal implementation of an attractive school curriculum.
Subject(s)
Diet , Dietary Services/methods , Feeding Behavior , Schools , Adolescent , Child , Child Nutrition Sciences , Female , Fruit , Humans , School Health Services , VegetablesABSTRACT
The objective of the present study was to evaluate the effects of the Pro Children intervention on schoolchildren's fruit and vegetable (FV) intake after 1 and 2 years of follow-up. The intervention combined a FV curriculum with efforts to improve FV availability at schools and at home. Effects were examined in a group-randomised trial among 1,472 10-11-year-old children from sixty-two schools in Norway, the Netherlands and Spain. FV intake was assessed by means of validated self-administered questionnaires completed before the intervention (September 2003), immediately after the first year of the intervention (May 2004) and 1 year later (May 2005). Data were analysed using multilevel linear regression analyses with age and sex as covariates. Significant intervention effects for FV intake were found at first follow-up in the total sample. The adjusted FV intake reported by the children from intervention schools was 20 % higher than FV intake reported by children from control schools. At 1 year later, a significant impact was only observed in Norway. Positive intervention effects on FV intake occurred both at school and outside school. We conclude that the Pro Children intervention is a promising means to promote European schoolchildren's FV intakes, but mainly fruit intake, in the short term. As shown in Norway, where the intervention was best implemented, the intervention might also result in longer-term effects. Further strategies need to be developed that can improve implementation, have an impact on vegetable intake and can secure sustained effects.
Subject(s)
Feeding Behavior , Food Preferences , Fruit , Health Promotion , School Health Services , Vegetables , Case-Control Studies , Child , Family Health , Follow-Up Studies , Humans , Linear Models , Netherlands , Norway , SpainABSTRACT
OBJECTIVES: To investigate the internal consistency of the scales and the test-retest reliability and predictive validity of behaviour theory-based constructs measuring personal, social and environmental correlates of fruit and vegetable intake in 10-11-year-old children. DESIGN: Test-retest with one-week interval. SETTING: Five European countries: Norway, Spain, Denmark, Portugal, Belgium. SUBJECTS: Three hundred and twenty-six children completed the questionnaire during class hours. RESULTS: For the total sample across all countries, the test-retest reliability was good to very good (intra-class correlation coefficient (ICC) >0.60) for 12 out of the 15 fruit constructs and also for 12 out of the 15 vegetable constructs. Acceptable ICCs, ranging between 0.50 and 0.59, were found for the remaining constructs. Test-retest reliability was comparable across countries. Only in Portugal were some significantly lower ICCs found for some constructs (knowledge and barriers related to fruit, general self-efficacy related to fruit and vegetables) compared with the other countries. Cronbach's alpha values were moderate to high (range 0.52 to 0.89) with the exception of the general self-efficacy scale, which had a value below 0.50 for both fruit (alpha=0.42) and vegetables (alpha=0.49). Spearman correlations with intake ranged between -0.16 and 0.54 for personal determinants and between 0.05 and 0.38 for environmental determinants. Compared with other studies, predictive validity can be considered moderate to good. CONCLUSIONS: The questionnaire provides a reliable, valid and easy-to-administer tool for assessing personal, social and environmental factors of potential influence on fruit and vegetable intake in 10-11-year-olds.
Subject(s)
Feeding Behavior/psychology , Fruit , Self Efficacy , Surveys and Questionnaires/standards , Vegetables , Attitude to Health , Child , Child Nutritional Physiological Phenomena , Diet Surveys , Environment , Female , Humans , Male , Nutrition Assessment , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
The local, temperature dependent structure of poly-(ethylmethacrylate) was studied with wide-angle x-ray scattering. The results were set into context to recent wide-angle neutron scattering results as well as to the results from a multitude of studies of the dynamics of this polymer. The temperature dependence of the wide angle x-ray results point to the development of local order which is backed by the neutron scattering results and which is connected to characteristic temperatures of the relaxation dynamic T(g) and T(c). The poly-(ethylmethacrylate) was studied in its predominantly syndiotactic as well as predominantly isotactic state displaying vastly different local structures as manifested in the x-ray results.
ABSTRACT
Available population data suggest that a high proportion of European children and young people eat less fruit and vegetables than desirable. School based health promotion strategies fostering healthy eating practices and regular physical activity has the potential for a major impact on health and wellbeing during childhood and later stages in life. The aim of Pro-Children project is to estimate the consumption of fruit and vegetables as well as its main determinants among 11 year old European children and their families. It also aims to develop and assess the effectiveness of a school-based intervention program to promote adequate consumption levels of fruit and vegetables among school children. In the first phase of the project, cross-sectional studies were carried out on random population samples in nine European countries. The study protocol included assessment of fruit and vegetable consumption and a questionnaire to ascertain key determinants. A school-based intervention program was designed based on the Attitude, Social Influence and Self-Efficacy model (ASE). Theoretically similar but culturally relevant interventions were designed to be tested in Norway, The Netherlands and Spain during two school years. Each intervention site follows-up 10 intervention schools implementing the program and 10 control schools. Intervention planning and design followed an intervention mapping procedure. Key behaviours and determinants to be addressed through the intervention were identified in order to develop a matrix of educational objectives. The provision of fruit and vegetables in the school is an outstanding element. Program activities include guided classroom activities, computer tailored messages for children, activities to be completed at home with the family and family targeted specific actions. Additionally, optional components for community reinforcement include mass media, school health services participation and implication of grocery stores in the project. Despite cultural and social diversity, common school-based strategies to increase fruit and vegetable consumption among children are feasible across Europe. Understanding specific situations will enhance implementation and gain support.
Subject(s)
Diet , Fruit , Health Promotion , Nutritional Sciences/education , School Health Services , Vegetables , Child , Cross-Sectional Studies , Europe , Feeding Behavior , Health Planning , HumansABSTRACT
Quality assurance is an important aspect in therapeutic drug monitoring (TDM). Capillary electrophoresis (CE) assays for determination of (i) ethosuximide via direct injection of serum or plasma, (ii) lamotrigine after protein precipitation by acetonitrile and analysis of an aliquot of the acidified supernatant, and (iii) carbamazepine and carbamazepine-10,11-epoxide after solute extraction followed by analysis of the reconstituted extract are characterized via analysis of a large number of commercial quality control sera containing up to 14 analytes (9 of them are anticonvulsants) in sub-therapeutic, therapeutic and toxicologic concentration levels. CE data obtained in single determinations are shown to compare well with the spike values and the mean of data determined in other laboratories using immunoassays and/or high-performance liquid chromatography, values that are reported by the external quality control scheme. Carbamazepine and ethosuximide drug levels are also shown to agree well with those determined in our departmental drug assay laboratory using automated immunoassays. The presented data reveal the effectiveness of assay assessment via analysis of quality control sera and confirm the robustness of the assays for TDM in a routine setting.
Subject(s)
Anticonvulsants/blood , Drug Monitoring/methods , Electrophoresis, Capillary/methods , Quality Control , Calibration , Humans , Reference StandardsABSTRACT
Capillary liquid chromatography (muLC) interfaced to inductively coupled plasma mass spectrometry (ICPMS) is introduced as a new micromethod to determine the phosphorylation degree in phosphoproteins and phosphopeptides containing cysteine and/or methionine residues. The stoichiometric phosphorus to sulfur (31P to 32S) ratio is experimentally determined by muLC-ICPMS and converted into the degree of phosphorylation using protein/ peptide sequence information. The method is applied to the phosphoproteins beta-casein, beta-casein, and recombinant protein kinase A catalytic subunit and to synthetic phosphopeptides. The accurate data obtained by muLC-ICPMS allow quantitative assessment of the compound-specific discrimination of the electrospray ionization process between nonphosphorylated and phosphorylated proteins and peptides.
Subject(s)
Chromatography, Liquid/methods , Mass Spectrometry/methods , Phosphoproteins/metabolism , Amino Acid Sequence , Catalytic Domain , Molecular Sequence Data , Phosphoproteins/chemistry , PhosphorylationABSTRACT
A method for phosphopeptide identification by capillary liquid chromatography (muLC) interfaced alternatively to element mass spectrometry (inductively coupled plasma mass spectrometry, ICPMS) and to electrospray ionization mass spectrometry (ESI-MS) is described. ICPMS is used for 31P detection and ESI-MS provides the corresponding molecular weight information. Alignment of the two separate muLC runs is performed using the baseline distortion at the elution front, which shows up in both muLC-ICPMS and muLC-ESI-MS. Both a quadrupole and a magnetic sector field mass analyzer were used in combination with ICP. The detection limit achieved for the muLC-ICP-HRMS runs is approximately 0.1 pmol of phosphopeptide injected. Without any further precautions, contamination by phosphate-containing compounds at this level was found to be uncritical. The method is demonstrated for the analysis of a complex mixture of synthetic phosphopeptides and a set of tryptic digests of three phosphoproteins. These include beta-casein, activated human MAP kinase ERK1, and protein kinase A catalytic subunit. The tryptic phosphopeptides of these proteins could all be detected and identified by our new strategy. Analysis of three fractions of protein kinase A catalytic subunit with different phosphorylation status gives direct access to the order in which the phosphorylation of the four phosphorylation sites occurs. The two most important aspects of using muLC-ICPMS with 31P detection for phosphopeptide identification are (i) that a high selectivity is achieved and (ii) that the signal intensity is independent of the chemical form of phosphorus and directly proportional to the molar amount of 31P in the muLC eluate. Thus, muLC-ICPMS with 31P detection is introduced as a new, robust, and specific method in phosphoproteomics.
Subject(s)
Proteins/chemistry , Amino Acid Sequence , Caseins/chemistry , Electrophoresis, Capillary , Mass Spectrometry , Molecular Sequence Data , Phosphorus Isotopes , Phosphorylation , Spectrometry, Mass, Electrospray IonizationABSTRACT
Separation of the enantiomers of chlorpheniramine and methadone in acidic buffers containing carboxymethyl-betacyclodextrin (CMCD) as chiral selector was investigated by capillary zone electrophoresis. For a range of pH and CMCD concentrations, the mobility difference and resolution of the enantiomers were determined. Then, conditions known to provide well resolved enantiomers and optimized chiral separation were applied to chiral continuous flow electrophoresis. In that approach, a thin film of fluid flowing between two parallel plates is employed as carrier for electrophoresis. The electrolytes and the sample are continuously admitted at one end of the electrophoresis chamber and are fractionated by an array of outlet tubes at the other. The number of pure enantiomeric fractions obtained by chiral continuous flow electrophoresis was found to be directly dependent on the enantiomeric mobility difference. For racemic chlorpheniramine separated in a betaine-acetic acid buffer at a total throughput of 5 mg/h, complete enantiomeric separation is shown to require a mobility difference of about 3 x 10(-9) m2/V s. Furthermore, compared to the previous investigations with hydroxypropyl-beta-cyclodextrin, CMCD was found to permit improved fractionation of methadone enantiomers. With a total racemic drug throughput of about 15 mg/h, continuous flow zone electrophoresis processing with CMCD as chiral selector is shown to have the potential of providing pure enantiomers on a mg/h scale. The results indicate that chiral capillary zone electrophoresis data can be employed as predictor for preparative scale chiral separations based upon continuous flow zone electrophoresis.
Subject(s)
Chlorpheniramine/isolation & purification , Electrophoresis, Capillary/methods , Methadone/isolation & purification , Chlorpheniramine/chemistry , Methadone/chemistry , StereoisomerismABSTRACT
RNA chain elongation by RNA polymerase II (pol II) is a complex and regulated process which is coordinated with capping, splicing, and polyadenylation of the primary transcript. Numerous elongation factors that enable pol II to transcribe faster and/or more efficiently have been purified. SII is one such factor. It helps pol II bypass specific blocks to elongation that are encountered during transcript elongation. SII was first identified biochemically on the basis of its ability to enable pol II to synthesize long transcripts. ((1)) Both the high resolution structure of SII and the details of its novel mechanism of action have been refined through mutagenesis and sophisticated in vitro assays. SII engages transcribing pol II and assists it in bypassing blocks to elongation by stimulating a cryptic, nascent RNA cleavage activity intrinsic to RNA polymerase. The nuclease activity can also result in removal of misincorporated bases from RNA. Molecular genetic experiments in yeast suggest that SII is generally involved in mRNA synthesis in vivo and that it is one type of a growing collection of elongation factors that regulate pol II. In vertebrates, a family of related SII genes has been identified; some of its members are expressed in a tissue-specific manner. The principal challenge now is to understand the isoform-specific functional differences and the biology of regulation exerted by the SII family of proteins on target genes, particularly in multicellular organisms.
Subject(s)
Transcription Factors, General , Transcription Factors/physiology , Transcriptional Elongation Factors , Animals , Humans , Protein Conformation , Protein Isoforms , Transcription Factors/chemistry , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
OBJECTIVES: To identify and assess dangers associated with placing children younger than 2 years to sleep in adult beds. This article focuses on overlying, wedging, and strangulation hazards and the relationship of these hazards to children's sleeping environments. DESIGN: A retrospective review and analysis of data collected by the US Consumer Product Safety Commission on deaths of children younger than 2 years in standard adult beds, daybeds, and waterbeds. The review included incident data from January 1990 through December 1997. RESULTS: The 8-year records showed a total of 515 deaths of children younger than 2 years who were placed to sleep on adult beds. Of these deaths, 121 were reported to be due to overlying of the child by a parent, other adult, or sibling sleeping in bed with the child and 394 were due to entrapment in the bed structure. Most of these deaths seem to have resulted from suffocation or strangulation caused by entrapment of the child's head in various structures of the bed. CONCLUSIONS: Placing children younger than 2 years to sleep in adult beds exposes them to potentially fatal hazards that are generally not recognized by the parent or caregiver. These hazards include overlying by a parent, sibling, or other adult sharing the bed; entrapment or wedging of the child between the mattress and another object; head entrapment in bed railings; and suffocation on waterbeds. Parents and caregivers should be alerted to these avoidable hazards.
Subject(s)
Asphyxia/etiology , Beds/adverse effects , Adult , Asphyxia/mortality , Asphyxia/prevention & control , Equipment Design , Female , Humans , Infant , Infant, Newborn , Parenting , Retrospective Studies , United States/epidemiologyABSTRACT
Elongation factor SII interacts with RNA polymerase II and enables it to transcribe through arrest sites in vitro. The set of genes dependent upon SII function in vivo and the effects on RNA levels of mutations in different components of the elongation machinery are poorly understood. Using yeast lacking SII and bearing a conditional allele of RPB2, the gene encoding the second largest subunit of RNA polymerase II, we describe a genetic interaction between SII and RPB2. An SII gene disruption or the rpb2-10 mutation, which yields an arrest-prone enzyme in vitro, confers sensitivity to 6-azauracil (6AU), a drug that depresses cellular nucleoside triphosphates. Cells with both mutations had reduced levels of total poly(A)+ RNA and specific mRNAs and displayed a synergistic level of drug hypersensitivity. In cells in which the SII gene was inactivated, rpb2-10 became dominant, as if template-associated mutant RNA polymerase II hindered the ability of wild-type polymerase to transcribe. Interestingly, while 6AU depressed RNA levels in both wild-type and mutant cells, wild-type cells reestablished normal RNA levels, whereas double-mutant cells could not. This work shows the importance of an optimally functioning elongation machinery for in vivo RNA synthesis and identifies an initial set of candidate genes with which SII-dependent transcription can be studied.
Subject(s)
RNA Polymerase II/genetics , RNA, Fungal/metabolism , Saccharomyces cerevisiae/genetics , Transcription Factors, General , Transcription Factors/genetics , Transcriptional Elongation Factors , Cell Division/drug effects , Mutation , RNA Polymerase II/metabolism , RNA, Messenger , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Time Factors , Transcription Factors/metabolism , Uracil/analogs & derivatives , Uracil/pharmacologyABSTRACT
A number of digital imaging techniques in medicine require the combination of multiple images. Using these techniques, it is essential that the images be adequately aligned and registered prior to addition, subtraction, or any other combination of the images. This paper describes an alignment routine developed to register an image of a fixed object containing a global offset error, rotation error, and magnification error relative to a second image. The described routine uses sparsely sampled regional correlation in a novel way to reduce computation time and avoid the use of markers and human interaction. The result is a fast, robust, and automatic alignment algorithm, with accuracy better than about 0.2 pixel in a test with clinical computed radiography images.