Three-dimensional scaffolds of fetal decellularized hearts exhibit enhanced potential to support cardiac cells in comparison to the adult

A main challenge in cardiac tissue engineering is the limited data on microenvironmental cues that sustain survival, proliferation and functional proficiency of cardiac cells. The aim of our study was to evaluate the potential of fetal (E18) and adult myocardial extracellular matrix (ECM) to support cardiac cells. Acellular three-dimensional (3D) bioscaffolds were obtained by parallel decellularization of fetal- and adult-heart explants thereby ensuring reliable comparison. Acellular scaffolds retained main constituents of the cardiac ECM including distinctive biochemical and structural meshwork features of the native equivalents. In vitro, fetal and adult ECM-matrices supported 3D culture of heart-derived Sca-1(+) progenitors and of neonatal cardiomyocytes, which migrated toward the center of the scaffold and displayed elongated morphology and excellent viability. At the culture end-point, more Sca-1(+) cells and cardiomyocytes were found adhered and inside fetal bioscaffolds, compared to the adult. Higher repopulation yields of Sca-1(+) cells on fetal ECM relied on β1-integrin independent mitogenic signals. Sca-1(+) cells on fetal bioscaffolds showed a gene expression profile that anticipates the synthesis of a permissive microenvironment for cardiomyogenesis. Our findings demonstrate the superior potential of the 3D fetal microenvironment to support and instruct cardiac cells. This knowledge should be integrated in the design of next-generation biomimetic materials for heart repair.

O Tabagismo em Terceira Mão: Um Conceito a (Re)Lembrar!

<strong>Keywords:</strong> Tobacco Smoke Pollution; Smoking.

Alpha-1 antitrypsin deficiency caused by a novel mutation (p.Leu263Pro): Pi*ZQ0gaia - Q0gaia allele

Severe alpha-1 antitrypsin deficiency (AATD) is generally associated with PI*ZZ genotype and less often with combinations of PI*Z, PI*S, and other rarer deficiency or null (Q0) alleles. Severe AATD predisposes patients to various diseases, including pulmonary emphysema. Presented here is a case report of a young man with COPD and AATD. The investigation of the AATD showed a novel mutation p.Leu263Pro (c.860T>C), which was named Q0gaia (Pi*ZQ0gaia). Q0gaia is associated with very low or no detectable serum concentrations of AAT.

Hiperplasia Congénita da Suprarrenal por Deficiência de 21-Hidroxílase: Correlação Genótipo-Fenótipo

<strong>Introduction:</strong> Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is one of the most frequent inborn conditions. It is caused by distinct mutations in the CYP21A2 gene and in the majority of cases the disease’s severity correlates with CYP21A2 allelic variation Our aim was to describe the mutational spectrum of CYP21A2 and evaluate genotype-phenotype correlation in a cohort of portuguese patients with 21-hydroxylase deficiency.<br /><strong>Material and Methods</strong>: Retrospective study of 22 patients with clinical diagnosis of 21-hydroxylase deficiency. Molecular analysis of CYP21A2 was performed and genotype-phenotype correlation was then established.<br /><strong>Results</strong>: Genotyping was performed in 22 unrelated patients: 5 with classic salt-wasting (average age of diagnosis 10,2 days; minimum 1, maximum 20 days), 7 with classic simple virilizing (average age of diagnosis 3,5 years; minimum 0 days, maximum 7 years) and 10 with nonclassical form (average age of diagnosis 5,7 years; minimum 4 years, maximum 8 years). The most frequent genetic defects in the classic forms were I2 splice (24%) and I172N (24%), followed by Q318X (16%) and gene deletions (16%) and in the nonclassical form, the V281L (80%). The overall concordance between genotype and phenotype was 81,8%. Genotype accurately predicted phenotype in 83,3%, 100% and 90% of patients with classic salt-wasting, classic simple virilizing and nonclassical mutations, respectively.<br /><strong>Discussion</strong>: The frequency of genetic defects in our patients was comparable to similar studies. In most cases there was a good correlation between genotype and phenotype.<br /><strong>Conclusions</strong>: Molecular analysis of CYP21A2 provides useful information in terms of prediction of disease severity, genetic and prenatal counseling.<br /><strong>Keywords</strong>: Adrenal Hyperplasia, Congenital; Genotype; Phenotype; Steroid 21-Hydroxylase.

[Congenital adrenal hyperplasia due to 21-hydroxylase deficiency: genotype-phenotype correlation]

INTRODUCTION

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is one of the most frequent inborn conditions. It is caused by distinct mutations in the CYP21A2 gene and in the majority of cases the disease's severity correlates with CYP21A2 allelic variation Our aim was to describe the mutational spectrum of CYP21A2 and evaluate genotype-phenotype correlation in a cohort of portuguese patients with 21-hydroxylase deficiency.

MATERIAL AND METHODS

Retrospective study of 22 patients with clinical diagnosis of 21-hydroxylase deficiency. Molecular analysis of CYP21A2 was performed and genotype-phenotype correlation was then established.

RESULTS

Genotyping was performed in 22 unrelated patients: 5 with classic salt-wasting (average age of diagnosis 10,2 days; minimum 1, maximum 20 days), 7 with classic simple virilizing (average age of diagnosis 3,5 years; minimum 0 days, maximum 7 years) and 10 with nonclassical form (average age of diagnosis 5,7 years; minimum 4 years, maximum 8 years). The most frequent genetic defects in the classic forms were I2 splice (24%) and I172N (24%), followed by Q318X (16%) and gene deletions (16%) and in the nonclassical form, the V281L (80%). The overall concordance between genotype and phenotype was 81,8%. Genotype accurately predicted phenotype in 83,3%, 100% and 90% of patients with classic salt-wasting, classic simple virilizing and nonclassical mutations, respectively.

DISCUSSION

The frequency of genetic defects in our patients was comparable to similar studies. In most cases there was a good correlation between genotype and phenotype.

CONCLUSIONS

Molecular analysis of CYP21A2 provides useful information in terms of prediction of disease severity, genetic and prenatal counseling.

Industrial noise and tooth wear - experimental study

Tooth wear is a complex multifactorial process that involves the loss of hard dental tissue. Parafunctional habits have been mentioned as a self-destructive process caused by stress, which results in hyperactivity of masticatory muscles. Stress manifests itself through teeth grinding, leading to progressive teeth wear. The effects of continuous exposure to industrial noise, a "stressor" agent, cannot be ignored and its effects on the teeth must be evaluated.

AIMS

The aim of this study was to ascertain the effects of industrial noise on dental wear over time, by identifying and quantifying crown area loss.

MATERIAL AND METHODS

39 Wistar rats were used. Thirty rats were divided in 3 experimental groups of 10 animals each. Animals were exposed to industrial noise, rich in LFN components, for 1, 4 and 7 months, with an average weekly exposure of 40 hours (8h/day, 5 days/week with the weekends in silence). The remaining 9 animals were kept in silence. The areas of the three main cusps of the molars were measured under light microscopy.

STATISTICAL ANALYSIS USED

A two-way ANOVA model was applied at significance level of 5%.

RESULTS

The average area of the molar cusps was significantly different between exposed and non-exposed animals. The most remarkable differences occurred between month 1 and 4. The total crown loss from month 1 to month 7 was 17.3% in the control group, and 46.5% in the exposed group, and the differences between these variations were significant (p<0.001).

CONCLUSIONS

Our data suggest that industrial noise is an important factor in the pathogenesis of tooth wear.

[Provocative tests in the diagnosis of childhood onset growth hormone insufficiency]

INTRODUCTION

The incidence of short stature associated with growth hormone deficiency has been estimated to be about 1:4000 to 1:10000. It is the main indication for treatment with recombinant growth hormone.

OBJECTIVES

The aims of the study were to evaluate the results of growth hormone stimulation tests and identify the growth hormone deficiency predictors.

MATERIAL AND METHODS

A cross-sectional, analytical and observational study was conducted. We studied all the children and adolescents submitted to growth hormone pharmacological stimulation tests between January 2008 and May 2012. Growth hormone deficiency diagnosis was confirmed by two negatives growth hormone stimulation tests (growth hormone peak < 7 ng/ml). The statistical analysis was performed using student t-test, chi-square, Pearson correlation and logistic regression. Statistical significance determined at the 5% level (p ≤ 0.05).

RESULTS

Pharmacological stimulation tests were performed in 89 patients, with a median age of 10 [3-17] years. Clonidine (n = 85) and insulin tolerance test (n = 4) were the first growth hormone stimulation tests performed. Growth hormone deficiency was confirmed in 22 cases. In cases with two growth hormone stimulation tests, the growth hormone peak showed a moderate correlation (r = 0.593, p = 0.01). In logistic regression model height (z-score) and the growth hormone peak in first stimulation test were predictors of growth hormone deficiency diagnosis (each one unit increase in z-score decrease the growth hormone deficiency probability).

DISCUSSION

Measurement of IGF-1 cannot be used in diagnosing growth hormone deficiency.

CONCLUSION

Auxological criteria associated with a positive test seems to be a reliable diagnostic tool for growth hormone deficiency.

Effects of industrial noise on circumpulpar dentin--a field emission scanning electron microscopy and energy dispersive spectroscopy analysis

Chronic exposure to Industrial Noise (IN), rich in Low Frequency Noise (LFN), causes systemic fibrotic transformation and sustained stress. Dental wear, significantly increased with exposure to LFN, affects the teeth particularly through the circumpulpar dentin. Our goal is to understand the consequences of IN exposure on the circumpulpar dentin of Wistar rats. 10 Wistar rats were exposed to IN for 4 months, according to an occupationally simulated time schedule and 10 animals were used as age-matched controls. The first and the second upper and lower molars of each animal were processed for observation by Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive Spectroscopy (EDS) analysis was performed. In exposed animals FESEM showed a 2.0 to 6.0 μm-dense mineral band between dentin and the pulp with no regular continuity with the tubules. This structure had a few tubules where the odontoblasts processes could be observed embedded within the band and collagen fibers were trapped inside. EDS analysis revealed that it was hydroxyapatite similar to dentin, with a higher carbon content. FESEM results show that the band may be tertiary reparative dentin formed by odontoblast-like cells, but the increased amount of carbon (EDS) could mean that it is sclerotic dentin. IN should be acknowledge as a strong stimulus, able to cause an injury to odontoblasts and to the formation of reparative tertiary dentin, in a process that may accelerate the aging of the teeth, either by direct impact of acoustic pressure pulsations or by increased stress and dental wear.

Iodo e Tiróide: O que o Clínico Deve Saber

The World Health Organization considers iodine deficiency as a major worldwide cause of mental and development diseases, estimating that about 13% of the world population is affected by diseases caused by iodine deficiency. Iodine is a trace element necessary for the synthesis of thyroid hormones which, since it cannot be formed by the organism, must be taken regularly with food. Fish and shellfish are generally a good source, because the ocean contains a considerable amount of iodine. On the contrary, plants which grow in iodine-deficient soils are poor in this element, as well as meat and other animal products fed in plants low in iodine. Salt is the best way for iodine supplementation. Cooking the food with iodized salt is a desirable practice because it guarantees the presence of this element. There are also other methods to provide iodine to the general population, such as adding iodine to drinking water or taking supplements of iodine. In pregnancy is recommended iodine supplementation, except in patients with known thyroid disorders. Iodine is an essential component of thyroid hormones (T4 and T3). Inadequate iodine intake leads to inadequate thyroid hormone production. The most important consequences of iodine deficiency, in the general population are goiter and hypothyroidism, and in the severe cases, mental retardation, cretinism and increased neo-natal and infant mortality. The International Council for the Control of Iodine Deficiency Disorders (ICCIDD) formed in 1985, with the only aim of achieving optimal iodine nutrition in the world, in cooperation with UNICEF and WHO. In Portugal, recent studies show significant deficiencies in pregnancy and The Portuguese Society of Endocrinology Diabetes and Metabolism, in partnership with General Directorate of Health, proposed an iodine supplementation during pregnancy with 150-200μg/day.

[Iodine and thyroid: what a clinic should know]

The World Health Organization considers iodine deficiency as a major worldwide cause of mental and development diseases, estimating that about 13% of the world population is affected by diseases caused by iodine deficiency. Iodine is a trace element necessary for the synthesis of thyroid hormones which, since it cannot be formed by the organism, must be taken regularly with food. Fish and shellfish are generally a good source, because the ocean contains a considerable amount of iodine. On the contrary, plants which grow in iodine-deficient soils are poor in this element, as well as meat and other animal products fed in plants low in iodine. Salt is the best way for iodine supplementation. Cooking the food with iodized salt is a desirable practice because it guarantees the presence of this element. There are also other methods to provide iodine to the general population, such as adding iodine to drinking water or taking supplements of iodine. In pregnancy is recommended iodine supplementation, except in patients with known thyroid disorders. Iodine is an essential component of thyroid hormones (T4 and T3). Inadequate iodine intake leads to inadequate thyroid hormone production. The most important consequences of iodine deficiency, in the general population are goiter and hypothyroidism, and in the severe cases, mental retardation, cretinism and increased neo-natal and infant mortality. The International Council for the Control of Iodine Deficiency Disorders (ICCIDD) formed in 1985, with the only aim of achieving optimal iodine nutrition in the world, in cooperation with UNICEF and WHO. In Portugal, recent studies show significant deficiencies in pregnancy and The Portuguese Society of Endocrinology Diabetes and Metabolism, in partnership with General Directorate of Health, proposed an iodine supplementation during pregnancy with 150-200µg/day.

[Iodine intake in Portuguese school children]

OBJECTIVE

The aim of the present study was to evaluate iodine intake in portuguese school children in order to inform health authorities of eventual measures to be implemented.

INTRODUCTION

Iodine is the key element for thyroid hormone synthesis and its deficiency even mild, as found in other European countries, may have deleterious effects in pregnancy resulting in cognitive problems of offsprings. In Portugal there are no recent data on iodine intake in schoolchildren.

POPULATION AND METHODS

3680 children aged 6-12 years of both sexes, from 78 different schools were studied. Iodine intake was evaluated trough urine iodine (UI) determinations using a colorimetic method.

RESULTS

The global median UI value was 105.5 µg/L; the percentage of children with UI <100 µg/L was 47.1%, corresponding to 41% of the studied schools. The percentage of values <50 µg/L was 11.8%. The male gender, the south region of the country and the distribution of milk in school were significantly linked with a higher iodine elimination.

DISCUSSION

Our global results point to a borderline/ mildly insufficient iodine intake in the portuguese school population. However 47% of the children had UI under 100 µg /L. The comparison of our results with the available data from 30 years ago, point to a considerable improvement, due to silent prophylaxis. Male gender, geographical area and milk distribution influenced positively iodine intake.The importance of milk has been referred in numerous papers.

CONCLUSIONS

The study of UI in the Portuguese school population points to a borderline iodine intake. However, in 47% of children iodine intake was inadequate. Compared with data from the eighties, a considerable increase in iodine elimination was found. Taking into account the potencial deleterious effects of inadequate iodine intake, a global prophylaxis with salt iodization has to be considered.

Iodine intake in Portuguese pregnant women: results of a countrywide study

BACKGROUND

Iodine is the key element for thyroid hormone synthesis, and its deficiency, even moderate, is harmful in pregnancy, when needs are increased, because of its potential deleterious effects on fetal brain development. In Portugal, no recent data on iodine intake exists. The objective of this countrywide study was to analyze iodine status in pregnant Portuguese women in order to propose adequate measures to the health authorities.

SUBJECTS AND METHODS

Using a fast colorimetric method, urine iodine concentration (UIC) was evaluated in 3631 pregnant women followed in 17 maternity hospitals from hinterland and coastal areas in Continental Portugal and the Portuguese islands of Açores and Madeira.

RESULTS

Median UIC value was 84.9 μg/l (range 67.6-124.1) in Continental Portugal, 69.5 μg/l in Madeira, and 50.0 μg/l in Açores. The percentage of satisfactory values (>150 μg/l) was 16.8, ranging from 8.8 to 34.1 in the Continent, and being 8.2 in Madeira and 2.3 in Açores. The percentage of values below 50 μg/l was 23.7, ranging from 14.0 to 37.4 in the Continent, 33.7 in Madeira, and 50.0 in Açores.

CONCLUSIONS

Our results point to an inadequate iodine intake in pregnant women assisted in most Portuguese maternity hospitals. Considering the potential deleterious effects of inadequate iodine supply in pregnancy, iodine supplementation is strongly recommended in this period of life.

In vivo formation and binding of SeHg complexes to the erythrocyte surface

The in vivo dynamics of selenium (Se) and mercury (Hg) interaction was studied in mouse tissues using direct visualization of individual Se, Hg, and SeHg particles on the surface of circulating erythrocytes. This high-resolution detection of Se and Hg was obtained by scanning electron microscopy coupled to X-ray microanalysis. BALB/c mice were injected in the peritoneal cavity with Se and Hg salts, and the animals were sacrificed 3 min after the Hg injection. Only a minority (9%) of the metal dots seen on mouse liver erythrocytes were SeHg complexes when Se and Hg salts were mixed together before injection. In contrast, the majority (73%) of metal dots on liver erythrocytes were SeHg complexes if Se was injected at least 5 min before Hg injection. All metal dots on liver erythrocytes were of SeHg complexes if Se was injected 9 or 12 min before the Hg injection. We conclude that the formation of stable in vivo SeHg complexes requires preliminary interaction of Se with a putative serum factor before complexes between Se and Hg are formed and are bound to the erythrocyte cell surface.