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Background: This study aimed to comprehensively analyze the overall congenital heart disease (CHD) prevalence in live births and children in Iran, along with evaluating the spatial distribution of CHD birth prevalence across various geographical regions within the country. Methods: A Bayesian hierarchical meta-analysis (PROSPERO 2022: CRD42022331281) was performed to determine the pooled prevalence. A systematic search was conducted using Web of Science, ScienceDirect, PubMed, Iranian Research Institute for Information Science and Technology (IranDoc), Scientific Information Database (SID), and Magiran until October 4, 2023. Cross-sectional and cohort studies in both English and Persian languages, focusing on the age range of 0-10 years, were considered for the study population. The study quality was evaluated using the Agency for Healthcare Research and Quality (AHRQ) Risk of Bias tool. Heterogeneity was assessed by I2 and t2 statistics, and publication bias by Egger's and Begg's tests. Results: The meta-analysis included 62 studies, revealing an overall CHD prevalence of 2.5 per 1000 births. Over time, CHD birth prevalence in Iran has consistently increased. Spatial distribution analysis, including spatial autocorrelation and local spatial autocorrelation, indicated no spatial clustering (P = .46) or aggregation (P = .65) among Iran's provinces. Geographic disparities were significant (P = .000), with the northern and eastern regions showing the highest and lowest CHD prevalence, respectively. Conclusion: The overall CHD prevalence in Iran is lower than global rates, but it continues to rise. Furthermore, there are variations in birth prevalence among different regions of Iran. Environmental, genetic, socioeconomic, and diagnostic accessibility differences are possibly involved in regional variation. The limitations like heterogeneity among studies, the potential inaccuracy of reports due to limited use of accurate diagnostic methods in some studies, and the absence of population-based models to investigate prevalence, underscore the urgent need for standardized diagnostic approaches, and the utilization of population-wide birth defect registries to accurately assess CHD prevalence in Iran. [ABSTRACT FROM AUTHOR]

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is an important tool for detecting subtle kinetic changes in cancerous tissue. Quantitative analysis of DCE-MRI typically involves the convolution of an arterial input function (AIF) with a nonlinear pharmacokinetic model of the contrast agent concentration. Parameters of the kinetic model are biologically meaningful, but the optimization of the nonlinear model has significant computational issues. In practice, convergence of the optimization algorithm is not guaranteed and the accuracy of the model fitting may be compromised. To overcome these problems, this paper proposes a semi-parametric penalized spline smoothing approach, where the AIF is convolved with a set of B-splines to produce a design matrix using locally adaptive smoothing parameters based on Bayesian penalized spline models (P-splines). It has been shown that kinetic parameter estimation can be obtained from the resulting deconvolved response function, which also includes the onset of contrast enhancement. Detailed validation of the method, both with simulated and in vivo data, is provided. Index Terms--Bayesian hierarchical modeling, dynamic contrast-enhanced magnetic resonance imaging, onset time, penalty splines, pharmacokinetic models, semi-parametric models.

This paper proposes a new method for estimating kinetic parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on adaptive Gaussian Markov random fields. Kinetic parameter estimates using neighboring voxels reduce the observed variability in local tumor regions while preserving sharp transitions between heterogeneous tissue boundaries. Asymptotic results for standard errors from likelihood-based nonlinear regression are compared with those derived from the posterior distribution using Bayesian estimation with and without neighborhood information. Application of the method to the analysis of breast tumors based on kinetic parameters has shown that the use of Bayesian analysis combined with adaptive Gaussian Markov random fields provides improved convergence behavior and more consistent morphological and functional statistics. Index Terms--Adaptive smoothing, Bayesian hierarchical modeling, dynamic contrast-enhanced magnetic resonance imaging, Gaussian Markov random fields, oncology, pharmacokinetic models.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.01.012 Byline: Tsuyoshi Momose, Volker Schmid Keywords: Axis determination; Endoderm; Determinant; Podocoryne carnea; Cnidaria Abstract: Cnidarians, in contrast with bilaterians, are generally considered to exhibit radial symmetry around a single body axis (oral-aboral) throughout their life-cycles. We have investigated how the oral-aboral axis is established in the hydrozoan jellyfish Podocoryne carnea. Vital labeling experiments showed that the oral end of the blastula derives from the animal pole region of the egg as has been demonstrated for other cnidarian species. Gastrulation is restricted to the oral pole such that the oral 20% of blastula cells give rise to endoderm. Unexpectedly, bisection experiments at the 8-cell stage showed that animal regions are able to develop into normally polarized larvae, but that vegetal (aboral) blastomeres completely fail to develop endoderm or to elongate. These vegetal-derived larvae also failed to polarize, as indicated by a lack of oral-specific RFamide-positive nerve cells and a disorganized tyrosinated tubulin-positive nerve net. A different result was obtained following bisection of the late blastula stage: aboral halves still lacked the capacity to develop endoderm but retained features of axial polarity including elongation of the larva and directional swimming. These results demonstrate for the first time in a cnidarian the presence of localized determinants responsible for axis determination and endoderm formation at the animal pole of the egg. They also show that axial polarity and endoderm formation are controlled by separable pathways after the blastula stage. Author Affiliation: Institute of Zoology, University of Basel, Biocenter/Pharmacenter, Klingelbergstrasse 50/70, 4056 Basel, Switzerland Article History: Received 20 November 2005; Revised 11 January 2006; Accepted 12 January 2006

The larval and polyp stages of extant Cnidaria are bi-layered with an absence of mesoderm and its differentiation products. This anatomy originally prompted the diploblast classification of the cnidarian phylum. The medusa stage, or jellyfish, however, has a more complex anatomy characterized by a swimming bell with a well-developed striated muscle layer. Based on developmental histology of the hydrozoan medusa this muscle derives from the entocodon, a mesoderm-like third cell layer established at the onset of medusa formation. According to recent molecular studies cnidarian homologs to bilaterian mesoderm and myogenic regulators are expressed in the larval and polyp stages as well as in the entocodon and derived striated muscle. Moreover striated and smooth muscle cells may have evolved directly and independently from non-muscle cells as indicated by phylogenetic analysis of myosin heavy chain genes (MHC class II). To accommodate all evidences we propose that striated muscle-based locomotion coevolved with the nervous and digestive systems in a basic metazoan Bauplan from which the ancestors of the Ctenophora (comb jellyfish), Cnidaria (jellyfish and polyps), as well as the Bilateria are derived. We argue for a motile tri-layered cnidarian ancestor and a monophyletic descent of striated muscle in Cnidaria and Bilateria. As a consequence, diploblasty evolved secondarily in cnidarian larvae and polyps. Keywords: Basic Bauplan; bHLH gene; Cnidaria; Entocodon; Hydrozoan jellyfish; Medusa; Mesoderm; Metazoan evolution; Monophyletic descent; Origin of triploblasty; Prebilaterian ancestor; Striated muscle; Zootype

The development of visual organs is regulated in Bilateria by a network of genes where members of the Six and Pax gene families play a central role. To investigate the molecular aspects of eye evolution, we analyzed the structure and expression patterns of cognate members of the Six family genes in jellyfish (Cnidaria, Hydrozoa), representatives of a basal, non-bilaterian phylum where complex lens eyes with spherical lens, an epidermal cornea, and a retina appear for the first time in evolution. In the jellyfish Cladonema radiatum, a species with well-developed lens eyes in the tentacle bulbs, Six1/2-Cr and Six3/6-Cr, are expressed in the eye cup. Six4/5-Cr is mainly expressed in the manubrium, the feeding, and sex organ. All three Six genes are expressed in different subsets of epidermal nerve cells, possibly of the RFamide type which are part of a net connecting the different eyes with each other and the effector organs. Furthermore, expression is found in other tissues, notably in the striated muscle. During eye regeneration, expression of Six1/2-Cr and Six3/6-Cr is upregulated, but not of Six4/5-Cr. In Podoeoryne carnea, a jellyfish without eyes, Six1/2-Pc and Six3/6-Pc are also expressed in the tentacle bulbs, Six1/2-Pc additionally in the manubrium and striated muscle, and Six3/6-Pc in the mechanosensory nematocytes of the tentacle. The conserved gene structure and expression patterns of all Cladonema Six genes suggest broad conservation of upstream regulatory mechanisms in eye development. Keywords: Six genes; Eye development; Eye regeneration; Jellyfish; Evolution

The close functional link of nerve and muscle cells in neuromuscular units has led to the hypothesis of a common evolutionary origin of both cell types. Jellyfish are well suited to evaluate this theory since they represent the most basal extant organisms featuring both striated muscle and a nervous system. Here we describe the structure and expression of two novel genes for basic helix loop--helix (bHLH) transcription factors, the Achaete-scute B family member Ash2 and the Atonal-like gene Atl1, in the hydrozoan jellyfish Podocoryne carnea. Ash2 is expressed exclusively in larval and adult endoderm cells and may be involved in differentiation of secretory cells. Atl1 expression is more widespread and includes the developing striated muscle as well as mechanosensory and nerve cell precursors in the medusa tentacles. Moreover, Atl1 expression is upregulated in proliferating nerve cell precursors arising from adult striated muscle cells by transdifferentiation in vitro. Likewise, the neuronal marker gene NP coding for the RFamide neuropeptide is expressed not only in mature nerve cells but also transiently in the developing muscle. The molecular evidence is concurrent to the hypothesis that muscle and nerve cells are closely linked in evolution and derive from a common myoepithelial precursor. Keywords: Achaete-scute; Atonal; Basic helix-loop helix; Cnidaria; Evolution; Muscle; Nerve; Neuropeptide; Podocoryne carnea; Transdifferentiation

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