78 research outputs found
Molecular Cloning and Copy Number Variation of a Ferritin Subunit (Fth1) and Its Association with Growth in Freshwater Pearl Mussel Hyriopsis cumingii
Iron is one of the most important minor elements in the shells of bivalves. This study was designed to investigate the involvement of ferritin, the principal protein for iron storage, in shell growth. A novel ferritin subunit (Fth1) cDNA from the freshwater pearl mussel (Hyriopsis cumingii) was isolated and characterized. The complete cDNA contained 822 bp, with an open reading frame (ORF) of 525 bp, a 153 bp 5′ untranslated region (UTR) and a 144 bp 3′ UTR. The complete genomic DNA was 4125 bp, containing four exons and three introns. The ORF encoded a protein of 174 amino acids without a signal sequence. The deduced ferritin contained a highly conserved motif for the ferroxidase center comprising seven residues of a typical vertebrate heavy-chain ferritin. It contained one conserved iron associated residue (Try27) and iron-binding region signature 1 residues. The mRNA contained a 27 bp iron-responsive element with a typical stem-loop structure in the 5′-UTR position. Copy number variants (CNVs) of Fth1 in two populations (PY and JH) were detected using quantitative real-time PCR. Associations between CNVs and growth were also analyzed. The results showed that the copy number of the ferritin gene of in the diploid genome ranged from two to 12 in PY, and from two to six in JH. The copy number variation in PY was higher than that in JH. In terms of shell length, mussels with four copies of the ferritin gene grew faster than those with three copies (P<0.05), suggesting that CNVs in the ferritin gene are associated with growth in shell length and might be a useful molecular marker in selective breeding of H. cumingii
Testicular Dysgenesis Syndrome and the Estrogen Hypothesis: A Quantitative Meta-Analysis
BACKGROUND: Male reproductive tract abnormalities such as hypospadias and cryptorchidism, and testicular cancer have been proposed to comprise a common syndrome together with impaired spermatogenesis with a common etiology resulting from the disruption of gonadal development during fetal life, the testicular dysgenesis syndrome (TDS). The hypothesis that in utero exposure to estrogenic agents could induce these disorders was first proposed in 1993. The only quantitative summary estimate of the association between prenatal exposure to estrogenic agents and testicular cancer was published over 10 years ago, and other systematic reviews of the association between estrogenic compounds, other than the potent pharmaceutical estrogen diethylstilbestrol (DES), and
TDS end points have remained inconclusive.
OBJECTIVES: We conducted a quantitative meta-analysis of the association between the end points related to TDS and prenatal exposure to estrogenic agents. Inclusion in this analysis was based on mechanistic criteria, and the plausibility of an estrogen receptor (ER)-–mediated mode of action was specifically explored.
RESULTS: We included in this meta-analysis eight studies investigating the etiology of hypospadias and/or cryptorchidism that had not been identified in previous systematic reviews. Four additional studies of pharmaceutical estrogens yielded a statistically significant updated summary estimate for testicular cancer.
CONCLUSIONS: The doubling of the risk ratios for all three end points investigated after DES exposure is consistent with a shared etiology and the TDS hypothesis but does not constitute evidence of an estrogenic mode of action. Results of the subset analyses point to the existence of unidentified sources of heterogeneity between studies or within the study population
PRIMARY HYPOTHYROIDISM, GROWTH HORMONE DEFICIENCY AND CONGENITAL MALFORMATIONS IN A CHILD WITH THE KARYOTYPE 46, XY, del(l)(q25q32)
Factors that influence the decision to perform a Karyotype in suspected disorders of sex development : lessons from the Scottish genital anomaly network register
Although a karyotype represents the first objective evidence of investigating a case of suspected disorder of sex development (DSD), the factors that influence the clinician's decision to initiate investigations are unclear. Cases of suspected DSD in Scotland were identified through the Scottish Genital Anomaly Network (SGAN) Register. The timing as well as other factors that influence the decision to perform a karyotype were subsequently studied. Results: Out of the 572 cases on the register, 383 (67%) were classified as having a non-specific disorder of under-masculinisation. In 463 (81%) cases, the sex of rearing was male, in 71 (12%) female, and in 38 (7%) cases data regarding sex of rearing were unavailable. A karyotype was reported to have been performed in 153/572 (27%) cases. Infants in Scotland with suspected DSD are more likely to have a karyotype performed in the presence of a low external masculinisation score, bilateral impalpable testes, proximal hypospadias, or associated malformations. These data represent the first attempt at benchmarking the decision to check a karyotype and investigate infants with suspected DSD. Whilst this decision may be related to the complexity of the genital anomaly, there are other factors that may influence this decision, and these require further exploration through more rigorous systems for data collection
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