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The edible sea urchin, Mesocentrotus nudus, is both an economically important mariculture species and an excellent model for studying reproductive development. The gonads are the only edible parts of sea urchins and increasing market demand for high-quality gonads has prompted increasing amounts of research into the molecular mechanisms of reproduction. Using a high-throughput sequencing technology, we performed transcriptome sequencing on the gonads of females and males, sampled before the spawning season, to identify genes involved in sex determination, sex differentiation and gametogenesis. Through a de novo transcriptome assembly approach, we obtained 104,039 unigenes, of which 40,471 (38.90%) showed homologies with known proteins in public databases. By comparing the expression levels of these unigenes in females and males, 15,368 differentially-expressed unigenes (DEGs) were identified. Compared with males, 9473 were up-regulated and 5895 were down-regulated in females. Multiple candidate genes were identified that may play important roles in spermatogenesis, oogenesis, and germ cell development. Furthermore, we identified and characterized several genes involved in sex determination and sex differentiation, such as dmrt1 and foxl2. The current study provides valuable molecular resources for studying the underlying mechanisms of reproduction in sea urchins.

Sea urchin (Mseocentrotus nudus) is an economically important mariculture species in several Asian countries. The growth rate and immunocompetence differ by sex in this species. However, the mechanisms of sex determination in M. nudus have remain unclear. In the present study, we focus on the dmrt1 gene of M. nudus (Mndmrt1) to investigate its dynamic expression pattern during different developmental stages. Real-time quantitative PCR (RT-qPCR) revealed that Mndmrt1 exhibits testis-specific expression and undetectable during the whole embryogenesis. With the development of ontogenetic, Mndmrt1 transcripts are first detected at 9 months post-fertilization (mpf). In addition, both the transcripts and protein of Mndmrt1 gene were specifically expressed in spermatogonia and spermatocytes, indicating that it might be a male germ cells marker in sea urchin. Significantly, the 1441 bp promoter sequence of Mndmrt1 gene was obtained by DNA walking, and one positive regulatory region at −1197/ −968 in the promoter, as well as one negative regulatory region at −1441/ −1198 have been identified by promoter activity analysis. Moreover, two regulatory regions contain multiple putative binding sites for transcription factors, including Sp1, Egr1, Sox5, CEBP, GATA and SRY. These findings suggest that Mndmrt1 may be related to testis differentiation and spermatogenesis in sea urchin and will provide an insight into understanding the regulatory mechanism of the dmrt1 gene.

Dead end (dnd), vertebrate-specific germ cell marker, had been demonstrated to be essential for primordial germ cell (PGC) migration and survival, and the link between PGC number and sex change had been revealed in some teleost species, but little is known about dnd in hermaphroditic vertebrates. In the present study, a protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides) dnd homologue (Ecdnd) was identified and characterized. Quantitative real-time PCR and in situ hybridization analysis revealed a dynamic and sexually dimorphic expression pattern in PGCs and germ cells of gonads. During sex changing, the Ecdnd transcript sharply increased in early transitional gonad, reached the highest level at late transitional gonad stage, and decreased after testis maturation. Visualization of zebrafish PGCs by injecting with RFP-Ecdnd-3'UTR RNA and GFP-zfnanos3-3'UTR RNA confirmed importance of Ecdnd 3'UTR for the PGC distribution. In addition, knockdown of EcDnd by using antisense morpholinos (MO) caused the ablation of PGCs in orange-spotted grouper. Therefore, the current data indicate that Ecdnd is essential for PGCs survival and may serve as a useful germ cell marker during gametogenesis in hermaphroditic grouper.

Sea urchin (Mesocentrotus nudus) is an economically important mariculture species in China and the gonads are the solely edible parts to human. The molecular mechanisms of gonad development have attracted increasing attention in recent years. Although the nanos2 gene has been identified as a germ cell marker in several invertebrates, little is known about nanos2 in adult sea urchins. Hereinto, we report the characterization of Mnnano2, an M. nudus nanos2 homology gene. Mnnanos2 is a maternal factor and can be detected continuously during embryogenesis and early ontogeny. Real-time quantitative PCR (RT-qPCR) and section in situ hybridization (ISH) analysis revealed a dynamic and sexually dimorphic expression pattern of Mnnano2 in the gonads. Its expression reached the maximal level at Stage 2 along with the gonad development in both ovary and testis. In the ovary, Mnnanos2 is specifically expressed in germ cells. In contrast, Mnnanos2 is expressed in both nutritive phagocytes (NP) cells and male germ cells in testis. Moreover, knocking down of Mnnanos2 by means of RNA interference (RNAi) reduced nanos2 and boule expression but conversely increased the expression of foxl2. Therefore, our data suggest that Mnnanos2 may serve as a female germ cell marker during gametogenesis and provide chances to uncover its function in adult sea urchin.

Nowadays, more and more infants are getting allergic to cow's milk protein, so it is urgent to search for infant formula powder with milk protein alternatives. In the present work, soy protein hydrolysate (SPH) was added to protein-free infant formula powder and the effects of SPH addition on proliferation and metabolism of Streptococcus thermophilus were studied. Compared with commercially available infant formula powder (CK) and protein-free milk powder (BK), the infant formula powder with 20% SPH significantly enhanced the proliferation of S. thermophilus in MRS medium, resulting in a higher cell density and greater viable counts. Moreover, the influence of SPH on the metabolism of S. thermophilus was investigated by analyzing the content of seven organic acids and H2O2 in the medium. The higher content of organic acids and H2O2 is consistent with the stronger antibacterial activity to Escherichia coli. As a consequence, the addition of SPH to infant formula powder can effectively promote the growth of probiotics and SPH may be a promising protein alternative in the infant formula powder.

The sea cucumber (Apostichopus japonicus) is an economically important mariculture species in Asia. However, the genetic breeding of sea cucumbers is difficult because the sexes cannot be identified by appearance. Therefore, studies on sex-related genes are helpful in revealing the mechanisms of sex determination and differentiation in sea cucumbers. P-element induced wimpy testis (piwi) is a germ cell marker involved in gametogenesis in vertebrates; however, the expression pattern and function during gametogenesis remain unclear in sea cucumbers. In this study, we identified a piwi homolog gene in A. japonicus (Ajpiwi1) and investigated its expression pattern, and function. Ajpiwi1 is a maternal factor and is ubiquitously expressed in adult tissues, including the ovary and testis. Ajpiwi1 expression is strong in early oocytes, spermatocytes, and spermatogonia; weak in mature oocytes; and undetected in spermatids and intra-gonadal somatic cells. The knockdown of Ajpiwi1 by RNA interference (RNAi) led to the downregulation of other conserved sex-related genes such as dmrt1, foxl2, and germ cell-less. Therefore, Ajpiwi1 might play a critical role during gametogenesis in A. japonicus. This study creates new possibilities for studying sex-related gene functions in the sea cucumber and builds a gene function research platform based on RNAi for the first time.

Doping different concentration of ZrO2in Mn:Fe:LiNbO3crystals, a series of Zr:Mn:Fe:LiNbO3crystals were grown by the Czochralski method. The infrared transmission spectra and the photo-damage resistant ability of the crystals were measured. The OH-absorption peak of Zr (2mol%):Mn:Fe:LiNbO3crystal shifts to ultraviolet. The photo-damage resistant ability of Zr (3mol%):Mn:Fe:LiNbO3crystal is about three orders of magnitude higher than that of Mn:Fe:LiNbO3crystals. The diffraction efficiency, response time of Zr:Mn:Fe:LiNbO3crystals were measured by two-wave coupling experiment. The response time of Zr (3mol%):Mn:Fe:LiNbO3crystal is only one tenth of that of Mn:Fe:LiNbO3. The mechanism of OH-absorption peak shifting and improvement of holographic storage properties was discussed.

Multiple nanos genes have been characterized in several fishes, but the functional implications of their various expression patterns remain unclear. In this study, we identified and characterized four nanos genes from a hermaphroditic fish orange-spotted grouper, Epinephelus coioides. Ecnanos1a and Ecnanos1b show divergent expression patterns, and the dynamic expression change of Ecnanos1a in pituitaries during sex change is associated with testis differentiation and spermatogenesis. Ecnanos2 and Ecnanos3 might be germline stem cells (GSCs) and primordial germ cells (PGCs)-specific markers, respectively. Significantly, Ecnanos3 3'-untranslated region (UTR) is necessary for PGC specific expression, where a non-canonical "GCACGTTT" sequence is required for miR-430-mediated repression of Ecnanos3 RNA. Furthermore, grouper Dead end (Dnd) can relieve miR-430 repression in PGCs by associating with a 23 bp U-rich region (URR) in Ecnanos3 3'-UTR. The current study revealed the functional association of multiple nanos genes with PGC formation and germ cell development in orange-spotted grouper, and opened up new possibilities for developing biotechnologies through utilizing the associations between Ecnanos3 and PGCs or between Ecnanos2 and GSCs in the hermaphroditic fish.

In this paper, the force, deformation and other factors of vane hydraulic damp dynamic seal are researched, which is used of theoretical, simulation about the lip seals sealing damping performance factors. In order to improve sealing performance vane hydraulic damp life, dynamic lip seal design, optimization and performance study is to provide the basis for the theory and engineering applications. The factors influencing sealing performance are considered, such as initial compressibility, sealing sping stiffness. The finite element analysis method can be effectively used to solve nonlinear material and sealing failure problem for the seal design, optimization and performance analysis, which provide a new approach and theoretical guidance to the rubber seal research.

Background Diabetic hearts are vulnerable to ischemia/reperfusion (I/R) injury. Pretreatment with exogenous calcitonin gene-related peptide (CGRP) exerts a cardioprotective effect against myocardial I/R injury. Our previous study found that the CGRP level was decreased in diabetic hearts. This study aimed to investigate whether up-regulation of CGRP could reduce I/R injury in diabetic hearts. Methods and results Adenovirus encoding the CGRP gene (Ad-CGRP) was injected intramyocardially in mice with or without streptozotocin (STZ) treatment. Three days after injection, the hearts were subjected to in vivo and in vitro I/R. Myocardial infarct size, cardiac function, lactate dehydrogenase (LDH) level in plasma and effluents, and cell mitochondrial function were measured. After ischemia (30min) and reperfusion (24h) in vivo , diabetes mellitus (DM) mice had greater myocardial infarct size than their nondiabetic counterparts, and released more LDH in plasma. However, CGRP gene transfer reduced myocardial infarct size and plasma LDH level in both non-DM and DM hearts. After 30min global ischemia and 40min reperfusion in vitro , the DM hearts demonstrated increased left ventricular end-diastolic pressure (LVEDP) and effluent LDH level, and decreased left ventricular developed pressure (LVDP), coronary flow (CF), as well as cell mitochondrial function, when compared with the non-DM hearts. Again, CGRP gene transfer could protect against I/R injury in both non-DM and DM hearts. Conclusions Adenovirus-mediated up-regulation of CGRP gene expression protects diabetic hearts against I/R injury.

Background: We hypothesized that the transient receptor potential vanilloid type 1 (TRPV1), which is found in the sensory nerve fibers, could modulate the cardiac function, be impaired by diabetes and could contribute to further severe postischemic heart injury. Methods and Results: Diabetes was induced in ICR mice by an intraperitoneal injection of streptozotocin. The expression of both TRPV1 and calcitonin gene-related peptide (CGRP) in diabetes mellitus (DM) hearts was significantly lower, as determined by Western blot and radioimmunoassay, respectively. During the ischemia/reperfusion, the cardiac function was measured by a Medlab system and the lactate dehydrogenase (LDH) in the effluents was measured by an ELISA kit. Compared with the non-DM hearts, the DM hearts demonstrated increased left ventricular end-diastolic pressure and decreased left ventricular developed pressure, heart rate and coronary flow, and also released more LDH in the effluents. Pretreatment with capsaicin attenuated the postischemic injury significantly in non-DM hearts, but not in DM hearts. Pretreatment with CGRP in both non-DM and DM hearts protected hearts against ischemic injury. Conclusions: The alteration of TRPV1 caused by diabetes is related to the poor recovery of cardiac function after myocardial ischemia. (Circ J 2009; 73: 1127-1132)