South China Sea Isopycnal-Surface Circulation

This paper investigates the seasonal variabilities of the South China Sea isopycnal-surface circulations and of the Kuroshio intrusion through the Luzon Strait using the U.S. Navy’s climatological temperature and salinity dataset (public domain) with ½8 3 ½8 resolution by the P-vector method. The representative pattern is a persistent basin-scale cyclonic circulation away from the surface, and a seasonally varying circulation with a weak anticylonic gyre in the summer and a strong cyclonic gyre in the winter near the surface. This pattern is consistent with a classical view of mean cyclonic circulation in large stratified lakes and semienclosed marginal seas by Emery and Csanady and with a recent numerical simulation using the navy’s Layered Ocean Model by Metzger and Hurlburt. The computed monthly volume transport through the Luzon Strait is negative (inflow) all year round with a minimum value of 213.7 Sv in February (strongest intrusion) and a maximum value of 21.4 Sv in September (weakest intrusion). The annual mean transport is 26.5 Sv (intrusion).Office of Naval Research NOMP ProgramNaval Oceanographic OfficeNaval Postgraduate SchoolChinese National Science Foundatio

South China Sea Isopycnal-Surface Circulation

This paper investigates the seasonal variabilities of the South China Sea isopycnal-surface circulations and of the Kuroshio intrusion through the Luzon Strait using the U.S. Navy’s climatological temperature and salinity dataset (public domain) with ½° x ½° resolution by the P-vector method. The representative pattern is a persistent basin-scale cyclonic circulation away from the surface, and a seasonally varying circulation with a weak anticylonic gyre in the summer and a strong cyclonic gyre in the winter near the surface. This pattern is consistent with a classical view of mean cyclonic circulation in large stratified lakes and semienclosed marginal seas by Emery and Csanady and with a recent numerical simulation using the navy’s Layered Ocean Model by Metzger and Hurlburt. The computed monthly volume transport through the Luzon Strait is negative (inflow) all year round with a minimum value of 213.7 Sv in February (strongest intrusion) and a maximum value of 21.4 Sv in September (weakest intrusion). The annual mean transport is 26.5 Sv (intrusion).Office of Naval Research NOMP ProgramNaval Oceanographic OfficeNaval Postgraduate Schoo

Cholesterol-directed nanoparticle assemblies based on single amino acid peptide mutations activate cellular uptake and decrease tumor volume.

Peptide drugs have been difficult to translate into effective therapies due to their low in vivo stability. Here, we report a strategy to develop peptide-based therapeutic nanoparticles by screening a peptide library differing by single-site amino acid mutations of lysine-modified cholesterol. Certain cholesterol-modified peptides are found to promote and stabilize peptide α-helix formation, resulting in selectively cell-permeable peptides. One cholesterol-modified peptide self-assembles into stable nanoparticles with considerable α-helix propensity stabilized by intermolecular van der Waals interactions between inter-peptide cholesterol molecules, and shows 68.3% stability after incubation with serum for 16 h. The nanoparticles in turn interact with cell membrane cholesterols that are disproportionately present in cancer cell membranes, inducing lipid raft-mediated endocytosis and cancer cell death. Our results introduce a strategy to identify peptide nanoparticles that can effectively reduce tumor volumes when administered to in in vivo mice models. Our results also provide a simple platform for developing peptide-based anticancer drugs

Ubiquitin C-terminal hydrolase-activity is involved in sperm acrosomal function and anti-polyspermy defense during porcine fertilization

The 26S proteasome, which is a multi-subunit protease with specificity for substrate proteins that are postranslationally modified by ubiquitination, has been implicated in acrosomal function and sperm-zona pellucida (ZP) penetration during mammalian fertilization. Ubiquitin C-terminal hydrolases (UCHs) are responsible for the removal of polyubiquitin chains during substrate priming for proteasomal proteolysis. The inhibition of deubiquitination increases the rate of proteasomal proteolysis. Consequently, we have hypothesized that inhibition of sperm acrosome-borne UCHs increases the rate of sperm-ZP penetration and polyspermy during porcine in vitro fertilization (IVF). Ubiquitin aldehyde (UA), which is a specific nonpermeating UCH inhibitor, significantly (P < 0.05) increased polyspermy during porcine IVF and reduced (P < 0.05) UCH enzymatic activity measured in motile boar spermatozoa using a specific fluorometric UCH substrate, ubiquitin-AMC. Antibodies against two closely related UCHs, UCHL1 and UCHL3, detected these UCHs in the oocyte cortex and on the sperm acrosome, respectively, and increased the rate of polyspermy during IVF, consistent with the UA-induced polyspermy surge. In the oocyte, UCHL3 was primarily associated with the meiotic spindle. Sperm-borne UCHL3 was localized to the acrosomal surface and coimmunoprecipitated with a peripheral acrosomal membrane protein, spermadhesin AQN1. Recombinant UCHs, UCHL3, and isopeptidase T reduced polyspermy when added to the fertilization medium. UCHL1 was detected in the oocyte cortex but not on the sperm surface, and was partially degraded 6-8 h after fertilization. Enucleated oocyte-somatic cell electrofusion caused polarized redistribution of cortical UCHL1. We conclude that sperm-acrosomal UCHs are involved in sperm-ZP interactions and antipolyspermy defense. Modulation of UCH activity could facilitate the management of polyspermy during IVF and provide insights into male infertility

Interspecific hybridization with African marigold (Tagetes erecta) can improve flower-related performance in French marigold (T. patula)

The present research was intended for interspecific hybridization between two male sterile African marigold lines and six self-lines of French marigolds. The results show that as indicated by the full seed number per capitulum, the pollen amount of French marigold pollen influenced the authentic compatibilities reckoned for the 10 cross combinations configured to some amount. Based on the field performance of these interspecific hybrids, it is known that the parental French marigold’s single-petaled and silvery flower type may well be improved to a heavy-petaled type while the flower colour remains the same or changes to a lighter version with the same hue. Furthermore, the progeny of certain crossings exceeded the male parents in terms of growth, leaf, and flower-related features, particularly plant height, crown breadth, flower number per plant, and ligulate flower quantity. The most remarkable finding was that, compared to the parental French marigold, most of the hybrid combinations' progeny could blossom 0-11 days earlier. Finally, we identified two excellent hybrid combinations that may be used as a reference for future breeding and commercialization of new marigold varieties

Generation of cloned transgenic pigs rich in omega-3 fatty acids

Meat products are generally low in omega-3 (n-3) fatty acids, which are beneficial to human health. We describe the generation of cloned pigs that express a humanized Caenorhabditis elegans gene, fat-1, encoding an n-3 fatty acid desaturase. The hfat-1 transgenic pigs produce high levels of n-3 fatty acids from n-6 analogs, and their tissues have a significantly reduced ratio of n-6/n-3 fatty acids (P < 0.001). © 2006 Nature Publishing Group

Increased Inhibition of the Amygdala by the mPFC may Reflect a Resilience Factor in Post-traumatic Stress Disorder: A Resting-State fMRI Granger Causality Analysis

Purpose: To determine whether effective connectivity of the amygdala is altered in traumatized subjects with and without post-traumatic stress disorder (PTSD).Materials and Methods: Resting-state functional MRI data were obtained for 27 patients with typhoon-related PTSD, 33 trauma-exposed controls (TEC), and 30 healthy controls (HC). Effective connectivity of the bilateral amygdala was examined with Granger causality analysis and then compared between groups by conducting an analysis of variance.Results: Compared to the HC group, both the PTSD group and the TEC group showed increased effective connectivity from the amygdala to the medial prefrontal cortex (mPFC). The TEC group showed increased effective connectivity from the mPFC to the amygdala relative to the HC group. Compared to the TEC group, the PTSD group showed increased effective connectivity from the amygdala to the supplementary motor area (SMA), whereas decreased effective connectivity was detected from the SMA to the amygdala. Both the PTSD group and the TEC group showed decreased effective connectivity from the superior temporal gyrus (STG) to the amygdala relative to the HC group. Compared to the HC group, the TEC group showed increased effective connectivity from the amygdala to the dorsolateral prefrontal cortex (dlPFC), while both the PTSD group and the TEC group showed decreased effective connectivity from the dlPFC to the amygdala. The PTSD group showed decreased effective connectivity from the precuneus to the amygdala relative to both control groups, but increased effective connectivity from the amygdala to the precuneus relative to the HC group.Conclusion: Trauma leads to an increased down-top excitation from the amygdala to the mPFC and less regulation of the amygdala by the dlPFC. The results suggest that increased inhibition of the amygdala by the mPFC may reflect a resilience factor, and altered amygdala-SMA and amygdala-STG effective connectivity may reflect compensatory mechanisms of brain function. These data raise the possibility that insufficient inhibition of the amygdala by the mPFC might lead to PTSD in those who have been exposed to traumatic incidents, and may inform future therapeutic interventions