Improving the efficiency of Y-chromosome detection and the quality of STR typing in forensic casework with an in-house made qPCR and HRM system based on SYTO™ 9 chemistry

DNA quantification prior to STR amplification is a crucial step in forensic casework. Obtaining good-quality genetic STR profiles depends mainly on the amount and integrity of the DNA input in the PCR. In addition, the detection of male trace DNA provides key information for forensic investigation.

AIM

To evaluate the correlation between the quantification results obtained with the previously developed Amel-Y system, and its ability to detect Y-chromosome DNA by HRM, with the resulting STR profiles, and to ultimately show that Amel-Y can be routinely used in forensic casework to improve STR and Y-STR results.

MATERIAL & METHODS

Biological samples derived from forensic casework (85 reference and 391 evidence samples) were quantified by the Amel-Y system (a duplex qPCR/HRM based on SYTO™ 9 chemistry) using Rotor-Gene 6000. STRs were amplified and analyzed with GeneAmp™ PCR System 9700 or Veriti™ Thermal Cyclers and ABI 3500 Genetic Analyzer, respectively.

RESULTS

After DNA normalization, a total of 386 STR profiles were obtained (305 full and 81 partial). Sex typing by HRM was 100% successful in reference samples. Male DNA was detected by HRM in 210 evidence samples. 80/201 were mixed with an excess of female DNA. In addition, Amel-Y was able to detect Y-chromosome DNA in mixed samples that did not amplify the Y-variant of Amelogenin marker with commercial STR kits. The reproducibility and precision of the Amel-Y system were demonstrated (CVCt% ≤ 9.55) within the dynamic range analyzed (0.016-50 ng/µL; 41 independent runs). Amel-Y also proved to be compatible with other real-time PCR platforms.

CONCLUSION

We demonstrated that Amel-Y is a robust quantification system that can be routinely used in forensic casework to obtain reliable autosomal STR profiles and can be suitable as a predictor for Y-STR typing success when male DNA is detected. HRM can be used as a rapid screening tool for male DNA detection in mixed samples. Alternative designs like Amel-Y offer independence from commercial quantification kits in forensic labs.

Three mutations at a Y-STR haplotype defy a paternal half-brothers kinship case analysis

This work presents the results of a DNA test aimed to determine a possible biological link of paternal half brotherhood of two males. The combined use of biparentally inherited markers (autosomal STRs) and a panel of 27 Y-STRs allowed us to determine the existence of a biological relationship of kinship, even after detecting three mutations at their Y-STR haplotypes along the analyses, constituting an infrequent multiple mutation situation. This case is an example illustrating the importance of having different analytical markers sets and strategies for clarifying complex kinship cases where mutations occur.

Clinical presentation and prognosis of COVID-19 in older adults with hypothyroidism: data from the GeroCovid observational study

BACKGROUND

The prevalence of hypothyroidism among older patients hospitalized for COVID-19 and its association with mortality is unclear. This study aims to investigate the prevalence of hypothyroidism in older COVID-19 inpatients and verify if this comorbidity is associated with a specific pattern of onset symptoms and a worse prognosis.

METHODS

COVID-19 inpatients aged ≥ 60 years, participating in the GeroCovid acute wards cohort, were included. The history of hypothyroidism was derived from medical records and the use of thyroid hormones. Sociodemographic data, comorbidities, symptoms/signs at the disease onset and inflammatory markers at ward admission were compared between people with vs without history of hypothyroidism. The association between hypothyroidism and in-hospital mortality was tested through Cox regression.

RESULTS

Of the 1245 patients included, 8.5% had a history of hypothyroidism. These patients were more likely to present arterial hypertension and obesity compared with those without an history of hypothyroidism. Concerning COVID-19 clinical presentation, patients with hypothyroidism had less frequently low oxygen saturation and anorexia but reported muscle pain and loss of smell more commonly than those without hypothyroidism. Among the inflammatory markers, patients with hypothyroidism had higher lymphocytes values. At Cox regression, hypothyroidism was associated with reduced in-hospital mortality only in the univariable model (HR = 0.66, 95% CI 0.45-0.96, p = 0.03); conversely, no significant result were observed after adjusting for potential confounders (HR = 0.69, 95% CI 0.47-1.03, p = 0.07).

CONCLUSIONS

Hypothyroidism does not seem to substantially influence the prognosis of COVID-19 in older people, although it may be associated with peculiar clinical and biochemical features at the disease onset.

Highly selective recovery of Ni(II) in neutral and acidic media using a novel Ni(II)-ion imprinted polymer

In this work, an original ion-imprinted polymer (IIP) was synthetized for the highly selective removal of Ni(II) ions in neutral and acidic media. First a novel functional monomer (AMP-MMA) was synthetized through the amidation of 2-(aminomethyl)pyridine (AMP) with methacryloylchloride. Following Ni(II)/AMP-MMA complex formation study, the Ni(II)-IIP was produced via inverse suspension polymerization (DMSO in mineral oil) and characterized with solid state ¹³C CPMAS NMR, FT-IR, SEM and nitrogen adsorption/desorption experiments. The Ni(II)-IIP was then used in solid-phase extraction of Ni(II) exploring a wide range of pH (from neutral to strongly acidic solution), several initial concentrations of Ni(II) (from 0.02 to 1 g/L), and the presence of competitive ions (Co(II), Cu(II), Cd(II), Mn(II), and Mg(II)). The maximum Ni(II) adsorption capacity at pH 2 and pH 7 reached values of 138.9 mg/g and 169.5 mg/g, that are among the best reported in literature. The selectivity coefficients toward Cd(II), Mn(II), Co(II), Mg(II) and Cu(II) are also very high, with values up to 38.6, 32.9, 25.2, 23.1 and 15.0, respectively. The Ni(II)-IIP showed good reusability of up to 5 cycles both with acidic and basic Ni(II) eluents.

Abstract 2266: Host genetic susceptibility to COVID-19 and pandemic -associated stressors

Background: Single nucleotide polymorphisms (SNPs) in IL-6, IL-1β, and IL-10 genes have been reported to impact infectious disease outcomes and are associated with altered emotional states. High levels of these cytokines, which have a role in regulating inflammation, have been detected among individuals with severe COVID-19 disease. The objective of this study was to examine if pro-inflammatory SNPs in the promoter region of IL-6, IL-1β, and IL-10 genes are associated with more severe COVID-19 disease and/or increased anxiety/stress levels in response to pandemic-associated stressors in a vulnerable Hispanic population that is part of the Puerto Rico Colorectal Cancer Registry.

Methods: TaqMan® SNP Genotyping Assays (ThermoFisher Scientific) for IL-1β (rs1143627), IL-6 (rs1800795), and IL-10 (rs1800871) were performed according to the manufacturer’s recommendations in individuals between the ages of 21 to 75 (n=136). We assessed their anxiety and stress levels using the Generalized Anxiety Disorder Questionnaire (GAD-7) and the Perceived Stress Scale (PSS). Of these individuals, we evaluated those that had been previously infected with COVID-19 (n=38) for their symptom severity through a questionnaire. Chi-Square tests and Multivariate Logistic Regressions were used to calculate associations and ORs.

Results: Preliminary analysis showed an association between having the homozygous IL-1β pro-inflammatory SNP and reporting fever as a symptom (OR=2.50, p-value=0.05). Individuals with the homozygous IL-10 pro-inflammatory SNP had higher odds of reporting difficulty breathing (OR= 4.51, p-value = 0.02), shortness of breath (OR=7.82, p-value=0.006), and fatigue as symptoms (OR=4.43, p-value=0.020. Further analysis also showed an association between having the homozygous IL-10 pro-inflammatory SNP and reporting at least 1 severe COVID-19 symptom (OR=3.38, p-value=0.046). Those with the homozygous or heterozygous IL-6 pro-inflammatory allele were less likely to report higher anxiety levels than those with the wild-type allele (OR=0.1447, p-value=0.04). We also observed that individuals between the ages of 21 to 49 were more likely to report changes in diet (OR=1.65, p-value=0.059) and constantly disinfecting as a pandemic-related stressor (OR=1.87, p-value=0.04) compared to individuals between the ages of 50 to 79.

Conclusions: Pro-inflammatory IL-1β and IL-10 SNPs were associated with reporting fever and more severe symptoms of COVID-19, respectively. Data analysis using a larger sample size is warranted and is currently underway. Studies focused on examining that factors that contribute to more severe COVID-19 symptoms and how pandemic-associated stressors promote higher inflammation levels as a result of increased stress/anxiety are needed to fully understand the long-term effects the pandemic on public health, including possible increases in cancer incidence due to chronic inflammation.

Citation Format: Maria Gonzalez-Pons, Valeria Valentin, Ingrid Montes-Rodriguez, Maria J. Sanchez, Fabiola M. Morales, Ibis R. Vera-Urbina, Valerie Maldonado-Pino, Estefania I. Ayala, Ediel Rodriguez, Hilmaris Centeno-Girona, Belisa Suarez, Leslie Casiano, Ana Sala, Marcia Cruz-Correa. Host genetic susceptibility to COVID-19 and pandemic -associated stressors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2266.

Ancestral genetic legacy of the extant population of Argentina as predicted by autosomal and X-chromosomal DIPs

Aiming to determine their ancestry diagnostic potential, we selected two sets of nuclear deletion/insertion polymorphisms (DIPs), including 30 located on autosomal chromosomes and 33 on the X chromosome. We analysed over 200 unrelated Argentinean individuals living in urban areas of Argentina. As in most American countries, the extant Argentinean population is the result of tricontinental genetic admixture. The peopling process within the continent was characterised by mating bias involving Native American and enslaved African females and European males. Differential results were detected between autosomal DIPs and X-DIPs. The former showed that the European component was the largest (77.8%), followed by the Native American (17.9%) and African (4.2%) components, in good agreement with the previously published results. In contrast, X-DIPs showed that the European genetic contribution was also predominant but much smaller (52.9%) and considerably larger Native American and African contributions (39.6% and 7.5%, respectively). Genetic analysis revealed continental genetic contributions whose associated phenotypic traits have been mostly lost. The observed differences between the estimated continental genetic contribution proportions based on autosomal DIPs and X-DIPs reflect the effects of autosome and X-chromosome transmission behaviour and their different recombination patterns. This work shows the ability of the tested DIP panels to infer ancestry and confirm mating bias. To the best of our knowledge, this is the first study focusing on ancestry-informative autosomal DIP and X-DIP comparisons performed in a sample representing the entire Argentinean population.

Prognostic value of pre-operative atrial fibrillation in patients with heart failure and secondary mitral regurgitation undergoing percutaneous mitral valve repair with MitraClip

Background

Limited data are available regarding the independent prognostic role of atrial fibrillation (AF) after transcatheter mitral valve repair with MitraClip.

Aims

We sought to evaluate the real impact of pre-operative AF in a wide series of patients with heart failure (HF) and secondary mitral regurgitation (MR) after MitraClip treatment.

Methods

The study included 605 patients with severe secondary MR from a multicenter international registry. Patients were stratified into two groups according to the presence or absence of pre-operative AF. The overall prevalence of pre-operative AF was 44%. Primary endpoint was 5-year overall death, secondary endpoints were 5–year cardiac death and first re-hospitalization for acute HF.

Results

At 5-year Kaplan-Meier (KM) analysis conducted in the entire study cohort, compared to patients without AF those with AF had significantly more adverse events in term of overall death (67% vs. 43%; p<0.001) (KM curve A) and cardiac death (65% vs. 37%; p=0.001) (KM curve B) and, moderately more re-hospitalization for acute HF (64% vs. 50%; p=0.048) (KM curve C). To account for baseline differences, patients were propensity score matched 1:1. After matching, 342 adequately matched patients were identified: compared to patients without AF, those with AF had higher rates of death and cardiac mortality but similar rates of re-hospitalization for acute HF.

Conclusion

In this large 5-year analysis of patients with HF undergoing MitraClip treatment for severe secondary MR, AF is common and associated with higher rates of both overall- and cardiac-death. However, AF doesn't seem to affect the benefit of the procedure in term of re-hospitalization for HF.

Funding Acknowledgement

Type of funding source: None

Smart Hydrogels for the Augmentation of Bone Regeneration by Endogenous Mesenchymal Progenitor Cell Recruitment

The treatment of bone defects with recombinant bone morphogenetic protein-2 (BMP-2) requires high doses precluding broad clinical application. Here, a bioengineering approach is presented that strongly improves low-dose BMP-2-based bone regeneration by mobilizing healing-associated mesenchymal progenitor cells (MPCs). Smart synthetic hydrogels are used to trap and study endogenous MPCs trafficking to bone defects. Hydrogel-trapped and prospectively isolated MPCs differentiate into multiple lineages in vitro and form bone in vivo. In vitro screenings reveal that platelet-derived growth factor BB (PDGF-BB) strongly recruits prospective MPCs making it a promising candidate for the engineering of hydrogels that enrich endogenous MPCs in vivo. However, PDGF-BB inhibits BMP-2-mediated osteogenesis both in vitro and in vivo. In contrast, smart two-way dynamic release hydrogels with fast-release of PDGF-BB and sustained delivery of BMP-2 beneficially promote the healing of bone defects. Collectively, it is shown that modulating the dynamics of endogenous progenitor cells in vivo by smart synthetic hydrogels significantly improves bone healing and holds great potential for other advanced applications in regenerative medicine.

Absorption and diffusion of a 645 nm diode laser beam in the bone. An ex vivo study

The present preliminary ex vivo study aims to assess the possible interaction between complex biological systems and laser light, through irradiation of different hard tissue samples. A 645 nm wavelength diode laser was adopted to perform the present evaluation. Due to known similarities to human tissues, swine tissue samples were used. Two samples of cortical bone measuring 4.4 mm and 4.7 mm of thickness and 2 samples of spongeous bone measuring 2.45 mm and 2.9 mm were harvested for the analysis of hard tissues. Mean absorption values were as follows: 128.82 mW standard deviation 8.74 for 2.45 mm spongeous bone sample; 132.34 mW standard deviation 7.66 for 2.9 mm spongeous bone sample; 140.59 mW standard deviation 5.97 for 4.4 mm cortical bone sample and 152.20 mW standard deviation 3.36 for 4.7 mm mucosa and cortical bone sample. Red-light laser with 645nm wavelength has the ability to reach cells in each layer of measured tissues.

National Health Care Network for children with oral clefts: organization, functioning, and preliminary outcomes

INTRODUCTION

Oral clefts are major congenital anomalies that may affect the lip and/or palate, and that may also involve the nose and nostrils. In Argentina, their prevalence is approximately 15 per 10 000 births. In 2015, the Ministry of Health of Argentina created a national health care network for children with oral clefts in Argentina through the joint work with the National Registry of Congenital Anomalies (Red Nacional de Anomalías Congénitas, RENAC) (coordinating center for the national network) and the SUMAR Program. The objective of this study was to describe the health care network and its preliminary outcomes.

POPULATION AND METHODS

A total of 61 centers that provided a comprehensive treatment for oral clefts or in collaboration with other centers were identified and accredited. Maternity centers were connected with treating centers grouped in health care network nodes.

RESULTS

In the period between March 2015 and February 2016, 550 newborn infants who were exclusively covered by the public health care system were identified. Among these, 18% had a cleft lip; 62%, cleft lip and palate; and 20%, cleft palate only; 75% were isolated cases and 25%, in association with other congenital anomalies.

CONCLUSION

Approximately 70% of children were assessed by a certified treating institution and are receiving treatment. The network seeks to improve data systematization, include the largest number of centers possible, strengthen interdisciplinary team work, and promote high-quality standards for treatments.

Human DNA degradation assessment and male DNA detection by quantitative-PCR followed by high-resolution melting analysis

We developed a q-PCR technique that simultaneously evaluates the extent of degradation and determines the gender of a human DNA donor. QYDEG HRM is a triplex real-time PCR whose products are analysed by high-resolution melting (HRM). The system produces three amplicons: (1) transducin (beta)-like 1, Y-linked (TBL1Y) (84bp); (2) large-target sequence (DGlt) (244bp); and (3) small-target sequence (DGst) (152bp). After HRM analysis, three melting peaks are detected in male DNA samples and two in female DNA samples. An imbalance between the DGst and DGlt melting peak heights allows for the estimation of the extent of DNA degradation. For sensitivity assessment, triplicate aliquots of 0.0032 to 50ng/μL DNA were tested, denoting good linearity and reproducibility. The results also showed the analysis to be precise and accurate in the DNA range of 0.04-5ng/μL. Diverse types of DNA samples were tested: experimentally heat-degraded DNA; crime scene samples derived from casework and highly degraded samples with partial STR profiles from corpse material and mass disaster events. The results were compared with those obtained from the Plexor^® and PowerQuant^® commercial kits. Additionally, the quantification results of the QYDEG HRM triplex correlate well with the STR amplification that was subsequently obtained. The method is simple, cost-effective and helpful for determining the DNA integrity and the sex of a sample donor in any field where human DNA quantification is required.

Primary mediastinal large B-cell lymphoma: Outcome of a series of pediatric patients treated with high-dose methotrexate and cytarabine plus anti-CD20

Between 2007 and 2013, 13 children diagnosed with primary mediastinal large B-cell lymphoma (PMLBL) were treated according to a modified version of AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica) LNH-97 protocol based on high-dose methotrexate, anthracyclines, and addition of anti-CD20. Ten patients achieved a continuous complete remission with front-line therapy. The overall 5-year survival was 91.7%, and event-free survival was 83.9%, with only one patient dying of progressive disease. Despite the few cases, these results demonstrate that this therapy, which includes anti-CD20, given in a multicenter setting, is feasible with acceptable toxicity in children with PMLBL.

Non-canonical WNT/PCP signalling in cancer: Fzd6 takes centre stage

Frizzled receptors are the mediators of the wnt canonical and non-canonical pathways, which play fundamental roles in cell differentiation and organism development. A large body of work indicates that dysregulation of wnt signalling is a feature of oncogenic transformation, but most of the studies published so far focus on the assessment of the consequences of aberrations of the canonical pathway in human cancer. In this review, we discuss the emerging role of the wnt non-canonical pathway regulated by frizzled receptor 6 (Fzd6) in the pathogenesis of different types of human malignancies. The function played by Fzd6 in the physiology of normal and cancer cells has been highlighted in the view that an increased knowledge of the signalling pathways upstream and downstream of this receptor could ultimately result in the identification of new targets for cancer therapy.

Analysis of uni and bi-parental markers in mixture samples: Lessons from the 22nd GHEP-ISFG Intercomparison Exercise

Since 1992, the Spanish and Portuguese-Speaking Working Group of the ISFG (GHEP-ISFG) has been organizing annual Intercomparison Exercises (IEs) coordinated by the Quality Service at the National Institute of Toxicology and Forensic Sciences (INTCF) from Madrid, aiming to provide proficiency tests for forensic DNA laboratories. Each annual exercise comprises a Basic (recently accredited under ISO/IEC 17043: 2010) and an Advanced Level, both including a kinship and a forensic module. Here, we show the results for both autosomal and sex-chromosomal STRs, and for mitochondrial DNA (mtDNA) in two samples included in the forensic modules, namely a mixture 2:1 (v/v) saliva/blood (M4) and a mixture 4:1 (v/v) saliva/semen (M8) out of the five items provided in the 2014 GHEP-ISFG IE. Discrepancies, other than typos or nomenclature errors (over the total allele calls), represented 6.5% (M4) and 4.7% (M8) for autosomal STRs, 15.4% (M4) and 7.8% (M8) for X-STRs, and 1.2% (M4) and 0.0% (M8) for Y-STRs. Drop-out and drop-in alleles were the main cause of errors, with laboratories using different criteria regarding inclusion of minor peaks and stutter bands. Commonly used commercial kits yielded different results for a micro-variant detected at locus D12S391. In addition, the analysis of electropherograms revealed that the proportions of the contributors detected in the mixtures varied among the participants. In regards to mtDNA analysis, besides important discrepancies in reporting heteroplasmies, there was no agreement for the results of sample M4. Thus, while some laboratories documented a single control region haplotype, a few reported unexpected profiles (suggesting contamination problems). For M8, most laboratories detected only the haplotype corresponding to the saliva. Although the GHEP-ISFG has already a large experience in IEs, the present multi-centric study revealed challenges that still exist related to DNA mixtures interpretation. Overall, the results emphasize the need for further research and training actions in order to improve the analysis of mixtures among the forensic practitioners.

Qualitative and quantitative analysis of antibody response against IFNβ in patients with multiple sclerosis

To date, inter-and intra-laboratory consistency of binding assays for measuring anti-interferon (IFN)β antibodies has not been assessed. In this investigation, two independent laboratories tested a library of 80 serum specimens obtained from multiple sclerosis (MS) patients treated with IFNβ. For binding antibodies (BAbs) evaluations, each laboratory used both a capture-ELISA (cELISA) and an enzyme-immuno-assay (EIA), which is commercially available. Samples were also tested for neutralizing antibodies (NAbs). Data demonstrated good intra-laboratory reliability (rpearson≥0.86), and a good overall agreement between the results obtained from the two centers, using both the cELISA (69/80 of observed agreements) and the EIA (67/80). Accordingly, kappa coefficients (K) showed good concurrence (K ≥ 0.651). There was also substantial agreement between cELISA and EIA measurements, as performed in both centers (Orbassano, 66/80, K = 0.631; Basel, 70/80, K = 0.717). However, by comparing NAbs and BAbs titers obtained with both assays, we found that a high degree of BAb-negative samples were positive in NAb-assay. Thus, our study does not support the usefulness of ELISA-based BAb assays as a screening tool for NAbs. Otherwise, BAb-assays can be used as a confirmation test, indicating that the decrease of the biological effects is due to antibodies. In this context, both ELISA-based assays are equally reliable techniques.

Lower-limb MRI in the staging and re-staging of osteonecrosis in paediatric patients affected by acute lymphoblastic leukaemia after therapy

PURPOSE

To assess the diagnostic value of MRI examination in detecting and monitoring osteonecrotic lesions (ON) in childhood acute lymphoblastic leukaemia (ALL) after chemotherapy (CHT) and/or bone marrow transplantation (BMT).

METHODS AND MATERIALS

Seventy-three patients (37 males, mean age 12.4 years old) with ALL after treatment underwent a lower-limb MR examination between November 2006 and March 2012. In 47 there was clinical suspicion of ON, 26 were asymptomatic. Studies were performed with a 1 T and a 1.5 T scanner, acquiring short tau inversion recovery (STIR) and T1-weighted sequences in coronal plane from the hips to the ankles. The average acquisition time was 18 min. Considering baseline and follow-up examinations, the overall number of MRI studies was 195.

RESULTS

Fifty-four of 73 patients showed ON at MRI study, with an overall number of 323 ON (89 involving articular surface, 24 with joint deformity, JD). Twenty-five of 47 symptomatic patients showed subchondral ON lesions, 11 developed JD. Three of 26 asymptomatic patients showed subchondral bone ON at baseline examination but no JD at follow-up. Twenty-two of 28 BMT, 32/45 CHT patients developed ON.

CONCLUSION

Our MRI protocol proved to be feasible in evaluating ON in paediatric patients. Studies should be addressed only to symptomatic patients.

Strategies to increase the hygienic and economic value of fresh fish: Biopreservation using lactic acid bacteria of marine origin

In this work we describe the development of a biopreservation strategy for fresh fish based on the use of bacteriocinogenic LAB of marine origin. For this purpose, two multibacteriocinogenic LAB strains, Lactobacillus curvatus BCS35 and Enterococcus faecium BNM58, previously isolated from fish and fish products were selected owing to their capability to inhibit the growth of several fish-spoilage and food-borne pathogenic bacteria. Two commercially important fish species were chosen, young hake (Merluccius merluccius) and megrim (Lepidorhombus boscii), and the specimens were acquired at the Marín (Pontevedra, Spain) retail fish market, after one night in the chilled hold of a near-shore fishing vessel. The biopreservation potential and the application strategies of these two LAB strains were first tested at a laboratory scale, where several batches of fresh fish were inoculated with: (i) the multibacteriocinogenic LAB culture(s) as protective culture(s); and/or (ii) their cell-free culture supernatant(s) as food ingredient(s), and (iii) the lyophilized bacteriocin preparation(s) as lyophilized food ingredient(s). All batches were stored in polystyrene boxes, permanently filled with ice at 0-2 °C, for 14 days. Microbiological analyses, as well as sensorial analyses, were carried out during the biopreservation trials. Subsequently, Lb. curvatus BCS35 was selected to up-scale the trials, and combinations of the three application methods were assayed. For this purpose, this strain was grown in a semi-industrial scale fermentor (150l) in modified MRS broth, and three batches of fresh fish were inoculated with the protective culture and/or food ingredient, and stored on ice in a chilled chamber at 0-2 °C at the Marín retail fish market for 14 days. Microbiological analyses were carried out during the storage period, showing that when Lb. curvatus BCS35 culture or the corresponding cell-free culture supernatant was used as protective culture or food ingredient, respectively, bacterial counts were significantly lower than those of the untreated control batches, both for young hake and megrim. In addition, the presence of Listeria spp. in megrim was inhibited in both analyses. The effect of protective culture or food ingredient on the sensory characteristics of fish was evaluated by an official fish appraiser from the Marín retail fish market, who concluded that all the biopreserved batches were worth a higher price in the fish market than the respective control batches, demonstrating that the multibacteriocinogenic strain of marine origin Lb. curvatus BCS35 may be considered as a suitable candidate for its application as fresh fish biopreservative.

Arsenic levels in immigrant children from countries at risk of consuming arsenic polluted water compared to children from Barcelona

Arsenic is a highly toxic element that pollutes groundwater, being a major environmental problem worldwide, especially in the Bengal Basin. About 40% of patients in our outpatient clinics come from those countries, and there is no published data about their arsenic exposure. This study compares arsenic exposure between immigrant and native children. A total of 114 children (57 natives, 57 immigrants), aged 2 months to 16 years, were recruited and sociodemographic and environmental exposure data were recorded. Total arsenic in urine, hair, and nails and arsenic-speciated compounds in urine were determined. We did not find significant differences in total and inorganic arsenic levels in urine and hair, but in organic arsenic monomethylarsenic acid (MMA) and dimethylarsinous acid (DMA) in urine and in total arsenic in nails. However, these values were not in the toxic range. There were significant differences between longer than 5 years exposure and less than 5 years exposure (consumption of water from tube wells), with respect to inorganic and organic MMA arsenic in urine and total arsenic in nails. There was partial correlation between the duration of exposure and inorganic arsenic levels in urine. Immigrant children have higher arsenic levels than native children, but they are not toxic. At present, there is no need for specific arsenic screening or follow-up in immigrant children recently arrived in Spain from exposure high-risk countries.

The bottom-up growth of edge specific graphene nanoribbons

The discovery of ballistic transport in graphene grown on SiC(0001) sidewall trenches has sparked an intense effort to uncover the origin of this exceptional conductivity. How a ribbon's edge termination, width, and topography influence its transport is not yet understood. This work presents the first structural and electronic comparison of sidewall graphene grown with different edge terminations. We show that armchair and zigzag terminated ribbons, grown from SiC, have very different topographies and interact differently with the substrate, properties that are critical to device architecture in sidewall ribbon electronics.

Cathode lens spectromicroscopy: methodology and applications

The implementation of imaging techniques with low-energy electrons at synchrotron laboratories allowed for significant advancement in the field of spectromicroscopy. The spectroscopic photoemission and low energy electron microscope, SPELEEM, is a notable example. We summarize the multitechnique capabilities of the SPELEEM instrument, reporting on the instrumental aspects and the latest developments on the technical side. We briefly review applications, which are grouped into two main scientific fields. The first one covers different aspects of graphene physics. In particular, we highlight the recent work on graphene/Ir(100). Here, SPELEEM was employed to monitor the changes in the electronic structure that occur for different film morphologies and during the intercalation of Au. The Au monolayer, which creeps under graphene from the film edges, efficiently decouples the graphene from the substrate lowering the Dirac energy from 0.42 eV to 0.1 eV. The second field combines magnetism studies at the mesoscopic length scale with self-organized systems featuring ordered nanostructures. This example highlights the possibility to monitor growth processes in real time and combine chemical characterization with X-ray magnetic circular dichroism-photoemission electron microscopy (XMCD-PEEM) magnetic imaging by using the variable photon polarization and energy available at the synchrotron source.

Effects of natalizumab on oligoclonal bands in the cerebrospinal fluid of multiple sclerosis patients: a longitudinal study

Retrospective studies show that natalizumab modifies oligoclonal immunoglobulin (IgG) bands (OCBs) in the cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients. In this study, we prospectively analyzed both serum and CSF samples from 24 MS patients, before and after 2 years of natalizumab-based therapy. Our results showed complete (55%) or partial (27%) disappearance of the OCBs in CSF samples that were taken after 2 years of therapy. Intrathecal IgG production, represented by the IgG index and IgGLoc, was also quantitatively reduced. Our data showed that natalizumab substantially modulates both intrathecal polyclonal and oligoclonal IgG production: This effect was much more potent than was previously reported.

Economic evaluation of treatment for acute lymphoblastic leukaemia in childhood

Berlin-Frankfurt-Munster (BFM) and Dana-Farber Cancer Institute (DFCI) consortia's treatment strategies for acute lymphoblastic leukaemia (ALL) in children are widely used. We compared the health effects and monetary costs of hospital treatments for these two strategies. Parents of children treated at seven centres in Canada, Italy and the USA completed health-related quality of life (HRQL) assessments during four active treatment phases and at 2 years after treatment. Mean HRQL scores were used to calculate quality-adjusted life years (QALYs) for a period of 5 years following diagnosis. Total costs of treatment were determined from variables in administrative databases in a universally accessible and publicly funded healthcare system. Valid HRQL assessments (n = 1200) were collected for 307 BFM and 317 DFCI patients, with costs measured for 66 BFM and 28 DFCI patients. QALYs per patient were <1.0% greater for BFM than DFCI. Median HRQL scores revealed no difference in QALYs. The difference in mean total costs for BFM (US$88 480) and DFCI (US$93 026) was not significant (P = 0.600). This study provides no evidence of superiority for one treatment strategy over the other. Current BFM or DFCI strategies should represent conventional management for the next economic evaluation of treatments for ALL in childhood.

Fuzzy systems evaluation: The inference error approach

An inference method based on an equation image of a rule-base and the minimization of a cost index (inference error) is presented. The method has several advantages: it has intuitive insight, allows more powerful rules, and also presents an interesting algebraic (minimum distance) and functional (subsethood) formulation of the meaning of inference. Analysis of internal quality and completeness of a fuzzy rule-base and validity checks of inference methods can be expressed as numeric indexes. This is applied to logical verification of common structures widely used in PID fuzzy controllers.

MicroRNA 143-145 deficiency impairs vascular function

MicroRNAs are required for vascular smooth muscle growth, differentiation and function. MiR143-145 modulates cytoskeletal dynamics and acquisition of the contractile phenotype by smooth muscle cells. Lack of this miRNA cluster results in decreased blood pressure and reduced vasocontraction. As all these observations point to a key role for miR143-145 in the vasculature, we investigated whether miR143-145 deficiency is associated with impaired vascular tone. Vasocontraction was assessed in isolated aortic rings from miR143-145 KO and wild type animals incubated with increasing concentrations of phenylephrine (10(-9)M to 10(-5)M) or KCl 0.3M. In both cases, aortic vessel contraction was dramatically reduced in miR143-145 KO animals compared to controls. Next, aortic rings were pre-contracted with phenylephrine (EC60: 10(-7)M) and concentration responses for acetylcholine were obtained. A significantly reduced vasodilation was observed in miR143-145 KO animals compared to controls and similar results were obtained when an exogenous donor of nitric oxide (sodium nitroprusside) was used. Endothelial nitric oxide synthase or guanylate cyclase mRNA expression were not different between the animal groups thus suggesting to investigate the effect of other vasodilators. Isoprenaline mediated vasodilation was significantly reduced in miR143-145 KO animals compared to controls in the absence or in the presence of the guanylate cyclase inhibitor ODQ (10(-4)M), suggesting that also beta adrenergic vasodilation is impaired following miR143-145 deficiency. Finally, the effect of a stable mimetic prostacyclin, namely iloprost, was investigated and again a reduced vasodilation was observed in miR143-145 KO animals. MiR143-145 deficiency is associated not only with altered vasocontraction but also with impaired vasodilation, which probably reflects the impaired VSMC differentiation phenotype reported in miR143-145 KO animals.

The pulmonary pharmacology of [4-methoxy-N1-(4-trans-nitrooxycyclohexyl)-N3-(3-pyridinylmethyl)-1,3-benzenedicarboxamide] (2NTX-99), an anti-atherotrombotic compound with therapeutic potential in pathological conditions that target lung vasculature

The pharmacological activity of 2NTX-99 ([4-methoxy-N1-(4-trans-nitrooxycyclohexyl)-N3-(3-pyridinylmethyl)-1,3-benzenedicarboxamide]) was investigated in vitro in the intact, rat pulmonary vasculature and in guinea pig airways. Rat lungs were perfused at constant flow and changes in vascular tone recorded. Challenge with the TXA₂ analogue 9,11-dideoxy-9α11α-methanoepoxy ProstaglandinF₂ (U46619, 0.5 μM) increased vessel tone (32.48±1.5 vs 13.13±0.56 mmHg; n=12). 2NTX-99 (0.1-100 μM; n=5), caused a concentration-dependent relaxation, prevented by 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ, 10 μM, n=4), an inhibitor of soluble guanylate cyclase. Acetylcholine (0.1-10 μM; n=3) and a reference NO-donor, isosorbide-5-mononitrate (5-100 μM; n=4), were ineffective. Intraluminal perfusion of washed human platelets (2 × 10⁸ cells/ml) increased intravascular pressure after challenge with arachidonic acid (AA, 2 μM; n=5), an increase abolished by acetylsalicylic acid and significantly reduced by 2NTX-99 (40 μM; n=5). TXB₂ in the lung perfusate was detected after platelet activation, 2NTX-99 inhibited TXA₂ synthesis (6.45±0.6 and 1.10±0.2 ng/ml, respectively). 2NTX-99 did not alter central or peripheral airway responsiveness to Histamine (0.001-300 μM; n=6), U46619 (0.001-3 μM, n=3) or LTD₄ (1 pM-1 μM; n=6). 2NTX-99 vasodilates the pulmonary vasculature via the release of nitric oxide (NO) and reduces intraluminal, AA-induced, TXA₂ formation. The combined activity of 2NTX-99 as an NO-donor and a TXA₂-synthesis inhibitor provides strong support for its potential therapeutic use in pathologies of the pulmonary vascular bed (e.g. pulmonary hypertension).

Engineering 3D cell instructive microenvironments by rational assembly of artificial extracellular matrices and cell patterning

Engineered artificial microenvironments hold enormous potential as models to study developmental, physiological, pathological, and regenerative processes under highly defined conditions. Such platforms aim at bridging the gap between traditional in vitro 2D culture systems and animal models. By dissecting the biological complexity into an amenable number of parameters, systemic manipulation and study in controllable environments closely resembling the in vivo situation is possible. Novel strategies that address the evaluation of either ECM components, growth factors or cell-cell interactions on cellular behaviour are being developed. However, reliable methods that simultaneously recapitulate the natural instructive microenvironments in terms of cell and matrix composition, biological cues, heterogeneity and geometry are not yet available. Such spatially-defined microenvironments may be necessary to initiate and guide the formation of artificial tissues by morphogenetic processes. In this work, we introduce a flexible strategy that relies on the combination of artificial extracellular matrices with patterning techniques as well as a layer-by-layer approach to mimic rationally-designed instructive milieus. By a rational arrangement of cells and defined biochemical and biophysical extracellular cues, we report control of cell migration and generation of an artificial vascularized bone tissue-like construct.

Elucidating the role of matrix stiffness in 3D cell migration and remodeling

Reductionist in vitro model systems which mimic specific extracellular matrix functions in a highly controlled manner, termed artificial extracellular matrices (aECM), have increasingly been used to elucidate the role of cell-ECM interactions in regulating cell fate. To better understand the interplay of biophysical and biochemical effectors in controlling three-dimensional cell migration, a poly(ethylene glycol)-based aECM platform was used in this study to explore the influence of matrix cross-linking density, represented here by stiffness, on cell migration in vitro and in vivo. In vitro, the migration behavior of single preosteoblastic cells within hydrogels of varying stiffness and susceptibilities to degradation by matrix metalloproteases was assessed by time-lapse microscopy. Migration behavior was seen to be strongly dependent on matrix stiffness, with two regimes identified: a nonproteolytic migration mode dominating at relatively low matrix stiffness and proteolytic migration at higher stiffness. Subsequent in vivo experiments revealed a similar stiffness dependence of matrix remodeling, albeit less sensitive to the matrix metalloprotease sensitivity. Therefore, our aECM model system is well suited to unveil the role of biophysical and biochemical determinants of physiologically relevant cell migration phenomena.

Enzyme mediated site-specific surface modification

Stable tethering of bioactive peptides like RGD to surfaces can be achieved via chemical bonding, biotin streptavidin interaction, or photocross-linking. More challenging is the immobilization of proteins, since methods applied to immobilize peptides are either not specific or versatile enough or might even compromise the protein's bioactivity. To overcome this limitation, we have employed a scheme that by enzymatic (transglutaminase) reaction allows the site-directed and site-specific coupling of growth factors and other molecules to nonfouling poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) coated surfaces under physiological conditions. By our modular and flexible design principle, we are able to functionalize these surfaces directly with peptides and growth factors or precisely position poly(ethylene glycol) (PEG)-like hydrogels for the presentation of growth factors as exemplified with vascular endothelial growth factor (VEGF).

Functionalized self-assembling peptide hydrogel enhance maintenance of hepatocyte activity in vitro

There is a major challenge in maintaining functional hepatocytes in vivo as these cells rapidly lose their metabolic properties in culture. In this work we have developed a bioengineered platform that replaces the use of the collagen I--in the traditional culture sandwich technique--by a defined extracellular matrix analogue, the self-assembling peptide hydrogel RAD16-I functionalized with biologically active motifs. Thus, after examining side by side the two culture systems we have found that in both cases hepatocytes acquired similar parenchymal morphology, presence of functional bile canaliculi structures, CYP3A2 induction by dexamethasone, urea production, secretion of proteins such as apolipoprotein (class A1, E, J), alpha(1)-microglobulin, alpha(1)-macroglobulin, retinol binding protein, fibronectin, alpha(1)-inhibitor III and biotin-dependent carboxylases. Interestingly, by assessing in more detail some other hepatic markers, one of the functionalized matrix analogues--carrying the 67 kD laminin receptor ligand--enhanced the gene expression of albumin, HNF4-alpha, MDR2 and tyrosine aminotransferase. We conclude that the use of a synthetic culture system with designed matrix functionalization has the advantage in controlling specific cellular responses.

The effect of sympathy on discriminatory attitudes toward persons living with HIV/AIDS in Puerto Rico: a hierarchical analysis of women living in public housing

As the number of persons living with HIV/AIDS (PLWHA) continues to increase in Puerto Rico, it becomes increasingly important to address the issues of stigma and other discriminatory attitudes. Therefore, the objective of the present study is to examine the attitudes toward PLWHA of a large sample of women living in public housing in Puerto Rico, including sympathy and support for PLWHA in the workplace and in school. A total of 1138 women completed a self-administered 218-item survey made up of questions that measured HIV-related knowledge, attitudes and behaviors. Levels of sympathy varied depending upon the target group, with HIV-infected drug users receiving the least sympathy. Most women reported that HIV-positive teachers should be allowed to teach and that HIV-positive children should be allowed to attend school. However, a significantly lower percentage reported that HIV-infected nurses should be allowed to continue working. Women who were more sympathetic toward PLWHA were more tolerant of PLWHA in the workplace and school, while those with inaccurate knowledge concerning HIV transmission were less tolerant. Also, those who knew a PLWHA were more tolerant. Levels of discriminatory attitudes in Puerto Rico are high and warrant both individual- and societal-level interventions.