Optimization of a modified Captiva EMR-lipid method based on micro-matrix solid-phase dispersion coupled with gas chromatography-mass spectrometry for the determination of nine bisphenols in mussel samples.

This work describes a reliable, cheap, easy and fast method for analysis of nine bisphenols in mussel samples by gas chromatography-mass spectrometry after trimethylsilylation. The modified method consisted of miniaturized matrix solid phase dispersion (micro-MSPD) in a glass Pasteur pipette using Captiva EMR (enhanced matrix removal)-lipid as the sorbent. Good linearity was obtained in the work range (1-500 µg L-1) with a correlation coefficient (R2) ≥ 0.998. The method accuracy and precision were determined at two concentration levels. The results show recoveries ranging from 55 to 111%. The precision varied from 1.95 to 11.4% (RSD). The whole quantification limits were between 0.056 and 3.42 µg per kg dry weight. The analytical procedure was applied for the analyses of five mussel samples collected from Galician Rias. The major compound was BPA, and wild mussels from Rías de Ferrol, Vigo and A Coruña had the highest levels. The proposed method is suitable for the analysis of BPA and its analogues in mussel samples.

Spatial distribution and source identification of phthalates and organochlorine compounds in Galician mussels (NW Spain).

The spatial distribution of five phthalate esters (PAEs) and 17 organochlorine compounds (OCs) in wild and raft mussels from Galician littoral collected in 2020, and its relationship with anthropogenic activities was studied in this work. The Rías de Foz and Muros-Noia were the most polluted by PAEs, while the Rías de Ferrol and Barqueiro by PCBs. The highest levels of all contaminants were present in wild mussel, except DEHP that were predominant in raft mussel. The levels of most PAEs were negatively correlated with levels of the lower chlorinated PCBs and OCPs. The spatial distribution of pollutants confirmed by PCA was affected by the proximity to anthropogenic sources, phthalates by urban wastewater and PCBs by industrial inputs, mainly. The study of human exposure assessment suggests that Risk Quotient values were < 1, so the consumption of Galician raft mussels did not pose a risk to human health.

Optimization of micro-QuEChERS extraction coupled with gas chromatography-mass spectrometry for the fast determination of phthalic acid esters in mussel samples.

In this study, a new miniaturized version of the analytical method based on the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) technique using Florisil in the cleanup step for extracting six phthalic acid esters (PAEs) in mussel samples was developed by using a design of experiments. For this purpose, 1.5 mL of ultrapure water and later, 1.5 mL of acetonitrile were added to 0.1 g of the lyophilized sample, followed by 0.3 g of a commercial extraction salt packet (magnesium sulfate, sodium chloride, sodium citrate dihydrate, and sodium hydrogencitrate sesquihydrate). The recovered extract was purified using 0.1 g of Florisil. The final extract was evaporated and reconstituted in 1 mL of hexane. The six phthalates were determined by a GC-MS (SIM) system. The whole method was validated at two concentration levels. Recoveries ranged from 79% to 108%. Reproducibility in terms of coefficients of variation was between 4.9% and 12.1%. The limits of quantification of the whole method were between 0.53 and 38.0 µg per kg dry weight. Five mussel samples coming from the Galician Rías were analysed using this method. Except for three of the five samples where DnOP (di-n-octyl phthalate) was below the limit of quantification, all PAEs were found in concentrations that ranged between 1.99 and 372.7 µg per kg dry weight.

Cross-cutting view of current challenges in paediatric solid organ and haematopoietic stem cell transplantation in Europe: the European Reference Network TransplantChild.

The low prevalence of European paediatric transplanted patients and scarcity of resources and expertise led to the need for a multidisciplinary network able to improve the quality of life of paediatric patients and families requiring a solid organ or haematopoietic stem cell transplantation. The European Reference Network (ERN) TransplantChild is one of the 24 ERNs established in a European legal framework to improve the care of patients with rare diseases. ERN TransplantChild is the only ERN focused on both solid organ and haematopoietic stem cell paediatric transplantation, based on the understanding of paediatric transplantation as a complex and highly specialised process where specific complications appear regardless the organ involved, thus linking the skills and knowledge of different organ disciplines. Gathering European centres of expertise in paediatric transplantation will give access to a correct and timely diagnosis, share expertise and knowledge and collect a critical mass of patients and data that increases the speed and value of clinical research outcomes. Therefore, the ERN TransplantChild aims for a paediatric Pan-European, Pan-transplant approach.

Distribution and trend of organochlorine pesticides in Galicia coast using mussels as bioindicator organisms. Possible relationship to biological parameters.

Contamination of organochlorine pesticides (OCPs) such as DDT and its metabolites (ΣDDs), γ-HCH (hexachlorocyclohexane), HCB (hexachlorobenzene), aldrin, endrin, isodrin and trans-nonachlor were investigated in wild mussels (Mytilus galloprovincialis) collected from Galician Rías (Rías of Ferrol, A Coruña, Muros, Arousa, Pontevedra and Vigo) during the period 1998-2012. Biological parameters, lipid content, shell length and condition index, were also studied. The OCPs levels in the wild mussel were in the order ΣDDs>γ-HCH>HCB. The other pesticides, aldrin, endrin, isodrin and trans-nonachlor, were not detected or were below the analytical detection limit. All concentrations found in these samples were below the allowable limits for human consumption (Regulation (EC) no. 396/2005). Univariate analysis confirmed that levels of some compounds presented significant relation with biological parameters. Multivariate analysis of the OCPs levels revealed significantly differences between studied Rías, samples from Ría of Ferrol had the highest levels of these compounds (values of ΣDDs ranged from 3.9 to 4.2 ng g(-1) ww) and samples from Ría of Arousa, the lowest levels (values of ΣDDs from 1.3 to 2.4 ng g(-1) ww). Temporal trends showed a decrease of OCPs levels along the studied period 1998-2012 in the Galician Rías.

A NMR reverse diffusion filter for the simplification of spectra of complex mixtures and the study of drug receptor interactions.

A reverse diffusion filter NMR experiment (Drev) is proposed for the study of small molecules in binding with macromolecules. The filtering efficiency of Drev to eliminate the signals of the macromolecule is shown to be superior to conventional transverse relaxation filters at least for macromolecules containing a significant fraction of flexible residues. The Drev filter was also a useful complement for ligand-based NMR screening in combination with saturation transfer difference experiments.

Assisted solvent extraction and ion-trap tandem mass spectrometry for the determination of polychlorinated biphenyls in mussels. Comparison with other extraction techniques.

A selective and sensitive analytical method for determination of ten congeners of polychlorinated biphenyls (PCBs 31, 28, 52, 101, 118, 153, 105, 138, 156, and 180) in mussel samples (Mytilus galloprovincialis) based on accelerated solvent extraction (ASE) and gas chromatography-tandem mass spectrometry (GC-MS-MS) is presented in this work. Extraction conditions were optimised using a Plackett-Burman factorial design. The final extracts were analysed after cleanup on alumina columns. The optimised extraction parameters were solvent percentage, sample amount, extraction temperature, pressure, static extraction time, flush percentage, and purge time. The results suggest that PCBs 118, 105, and 180 extractions appeared affected by only one statistically significant factor, pressure, solvent percentage and static extraction time, respectively. Extraction of PCBs 138 and 156 was affected by amount of sample. PCB 138 extraction was also statistically affected by static extraction time and purge time. Quantitative recoveries (64.8-120.3%) were achieved for all PCBs and method precision (RSD < 19%) was satisfactory.

A new general-purpose fully automatic baseline-correction procedure for 1D and 2D NMR data.

A new procedure for automatic baseline correction of NMR data sets is presented. It is based on an improved automatic recognition of signal-free regions that uses a Continuous Wavelet transform derivative calculation, followed by a baseline modelling procedure based on the Whittaker smoother algorithm. The method has been proven to automatically flatten 1D and 2D NMR spectra with large baseline distortions arising from different sources, is tolerant to low signal-to-noise ratio spectra, and to signals of varying widths in a single spectrum. Even though this procedure has so far only been applied to NMR spectra, we believe it to also be applicable to other spectroscopies having relatively narrow peaks (e.g., mass spectrometry), and potentially to those with broad peaks (e.g., near infrared or ultraviolet).

Distribution of aliphatic compounds in bivalve mollusks from Galicia after the Prestige oil spill: spatial and temporal trends.

The content and distribution of n-alkane (C8-C35) and isoprenoid (pristane and phytane) hydrocarbons were investigated in two species of bivalve mollusk, mussel (Mytilus galloprovincialis) and cockle (Cerastoderma edule), collected at different points of the Galicia littoral zone during the period from December 2002 to February 2003 (after the Prestige oil spill). Samples were analyzed by high-resolution gas chromatography equipped with a flame ionization detector. The highest levels were found in mussels and cockles coming from two estuarine bays, Rías de Arousa and Vigo. Hydrocarbons with carbon chain length > 30 were detected and determined in all samples. The abundance of these hydrocarbons in biota could be interpreted with regard to the feeding and living habits. Chemometric techniques have been employed to analyze data and determine the potential source of hydrocarbon contamination. Differences between mussels and cockles were observed in relation to aliphatic content. According to the data analysis, the main source of hydrocarbon contamination of investigated samples seems to be more related to the intense traffic of vessels in these estuarine bays than to the Prestige oil spill.

A two-stage approach to automatic determination of 1H NMR coupling constants.

(1)H NMR scalar coupling constants are a rich source of information on molecular structure, but their extraction from spectra can be less than straightforward. Previous approaches to J extraction include methods proposed by Hoye, Golotvin, and the 'modified J-doubling' method. Here we describe the ACCA method, currently implemented in the NMR package MestReC, which allows a high degree of automation in the extraction of coupling patterns even in the case of complex multiplets with sublinewidth splitting. The new approach is illustrated by application to strychnine, for which it has detected previously unreported couplings.

A homodecoupled diffusion experiment for the analysis of complex mixtures by NMR.

Diffusion ordered spectroscopy (DOSY) relies on differences in translation diffusion as a means to separate components in a solution mixture. However, the analysis of spectra of mixtures can be problematic because spectral overlap. It is the aim of this article to propose a pulse sequence and processing method that leads to a complete 2D homodecoupled-DOSY experiment. This experiment offers several advantages that could extend the range of applications to more complex mixtures by achieving important improvements in both signal dispersion and sensitivity.

Wavelet-based ultra-high compression of multidimensional NMR data sets.

The application of a lossy data compression algorithm based on wavelet transform to 2D NMR spectra is presented. We show that this algorithm affords rapid and extreme compression ratios (e.g., 800:1), providing high quality reconstructed 2D spectra. The algorithm was evaluated to ensure that qualitative and quantitative information are retained in the compressed NMR spectra. Whilst the maximum compression ratio that can be achieved depends on the number of signals and on the difference between the most and the least intense peaks (dynamic range), a compression ratio of 80:1 is affordable even for the challenging case of homonuclear 2D experiments of large biomolecules.

Successful use of tissue plasminogen activator in catheter-related intracardiac thrombus of a premature infant.

The incidence of clinically apparent neonatal thrombosis is about 0.1 to 0.2% in the neonatal intensive care unit (NICU). The optimal treatment modalities for neonates with thromboses are not known. We report on our experience with recombinant tissue type plasminogen activator (rt-PA) in a premature infant with an intracardiac thrombus.

Specifying the antecedents of breast-feeding duration in Peru through a structural equation model.

OBJECTIVE: To examine the effects of socioeconomic status and biocultural variables (planned pregnancy, prenatal care, timing of initiation of breast-feeding and caesarean section delivery) on breast-feeding duration in Peru using structural equation models. DESIGN AND SETTING: Structural equation models were analysed with LISREL using data from the 1991-92 Peruvian Demographic and Health Survey. SUBJECTS: Models were tested among 6,020 women whose last child was born within 5 years of the survey and among 2,711 women whose last child was born 2-5 years preceding the survey. RESULTS: Unplanned pregnancy and socioeconomic status had a negative influence on breast-feeding duration. Prenatal care was positively associated with the timing of breast-feeding initiation in both samples and with breast-feeding duration in the whole sample. The timing of breast-feeding initiation was inversely associated with breast-feeding duration only in the sample of older children. CONCLUSIONS: These results imply that an unplanned pregnancy, a delayed breast-feeding initiation, and higher socioeconomic status are risk factors for an earlier discontinuation of breast-feeding through complex mechanisms involving direct and indirect effects.

Acculturation and low-birthweight infants among Latino women: a reanalysis of HHANES data with structural equation models.

Previous studies have demonstrated that acculturation is associated with negative birth outcomes among mothers in numerous immigrant populations, including Latinas. This study used structural equation models to reanalyze data employed in the 1989 Scribner and Dwyer study on the effect of acculturation (measured through the Cuellar scale) on mothers' low-birthweight status. Data revealed that language components dominate the effects of acculturation on low-birthweight status. Acculturuation appears to affect low-birthweight status indirectly through smoking and dietary intake but not through parity. Acculturation has a persistent direct effect on low-birthweight status, suggesting that other intervening variables are operant.

What predicts breastfeeding intention in Mexican-American and non-Hispanic white women? Evidence from a national survey.

We examined the effects of a series of predictors on the prepartum intention to breastfeed in both Mexican-American and non-Hispanic white women. A national sample included 430 Mexican-American women and 3659 non-Hispanic white women who had a pregnancy in 1988. Prenatal behavioral, sociodemographic, and biomedical information was obtained through the 1988 National Maternal and Infant Health Survey. Two dependent variables were constructed to identify significant predictors of breastfeeding intention: exclusive versus partial and bottle-feeding, and exclusive and partial versus bottle-feeding. Results from the multiple logistic regression models indicated that advice to breastfeed at prenatal care was the strongest predictor of intentions in both Mexican-American (OR = 2.15, OR = 1.86) and non-Hispanic white mothers (OR = 2.29, OR = 3.61). In Mexican-Americans the father's being Hispanic was negatively associated with breastfeeding intention (OR = 0.63). In non-Hispanic whites the advice to formula feed at the Women, Infants, and Children's nutrition program was a significant negative predictor of breastfeeding intention (OR = 0.33, for exclusive and partial breastfeeding vs exclusive bottle-feeding). These results have important implications for public health policy and practice.

Overweight among Mexican Americans and its relationship to life style behavioral risk factors.

The hypothesis positing differences between Mexican Americans and whites regarding attitudes and behaviors concerning obesity and other health issues was tested. A random sample of 1171 whites and 155 Mexican Americans aged 18 to 65 was selected. Two analyses were carried out. First, overweight Mexican Americans were compared with overweight whites. Second, overweight individuals were compared with normal weight counterparts within each ethnic group. Differences between overweight Mexican Americans and overweight whites disappeared after adjusting for the effects of sex, income, educational status, and marital status. Among whites, several factors remained significantly different when comparing overweight with normal weight individuals. Among Mexican Americans, however, all but one of the significant differences between overweight and normal weight individuals disappeared after adjusting for other variables. The implications of these results as they relate to the implementation of public health programs to deal with the prevention and treatment of obesity among Mexican Americans are discussed.

Ethnic enclaves and middleman minorities: alternative strategies of immigrant adaptation?

PIP: This article examines 2 modes or strategies of immigrant adaptation: middleman minorities and ethnic enclaves. Although they have been discussed as if they were disjointed and mutually exclusive, the authors challenge this view. Middleman minorities 1) tend to be self-employed or to work for a coethnic, 2) are usually concentrated in small business, 3) tend to rely on the in-group for resources, and 4) fill a "status gap" in the receiving society. Ethnic enclaves depend on 3 features: 1) recent coethnic arrivals spend a tour of duty at the worst jobs, 2) coethnics provide ethnic entrepreneurs with consumer markets, 3) ethnic businesses rely on each other to supply their operating needs. Ethnic enclaves are concentrated and spatially identifiable. For this study, the authors collected data in a survey of the Cuban exile community of San Juan, Puerto Rico. The sample selection procedure yielded a total of 261 individuals, 220 of whom were interviewed. 10 predictions found in the middleman minority and ethnic enclave perspectives were checked against the researchers' data. 4 of these predictions are hld in common by both approaches: 1) eomployment in an ethnic enterprise increases subsequent chances of self-employment, 2) ethnic firms rely on the in-group for business resources, 3) coethnic workers represent an asset to the ethnic entrepreneur in that they occupy important positions requiring the employer's trust, and 4) there is business competition between locals and minority members. As predicted by the middleman strategy, Cuban businesses in Puerto Rico tend not to be immediately productive and there is no evidence of spatial concentration of these businesses. However, fitting the enclave approach, these firms do not dominate certain business lines, Cuban entrepreneurs do not appear to be sojourners, and they tend to have business backgrounds. The middleman perspective is supported in that some elements of the local elite favor Cuban exiles. Thus, there is no evidence to support treating the middleman minority and ethnic enclave models as disjointed and discordant theoretical models. Neither approach is entirely accurate or inaccurate. The authors suggest that the 2 modes of adaptation are ideal types; therefore, actual ethnic economies exhibit some features found in each one.^ieng