Diversity and Distribution of Fiddler Crabs (Crustacea: Brachyura: Ocypodidae) in Vietnam.

Based on recently collected material and records in the literature, 14 species of fiddler crabs (Crustacea: Ocypodidae: Gelasiminae) are reported from Vietnam. DNA barcoding analyses using the mitochondrial gene COI (cytochrome c oxidase subunit I) was performed to identify examined materials and their precise distributional range. Thirteen species-level taxa are identified and, with the exception of Galsimus borealis and G. vocans, have minimum interspcific divergences of at least 7.27%. The identified species include seven species of Tubuca Bott, 1973, three of Austruca Bott, 1973 and three of Gelasimus Latreille, 1817, and one Paraleptuca Bott, 1973. Two new records of Vietnam are herein reported: Tubuca rhizophorae and T. dussumieri. The southernmost distribution limits of East Asian G. borealis, T. acuta and T. arcuata are in northern Vietnam, A. lactea in central Vietnam, whereas northernmost limit of Southeast Asian T. rhizophorae and T. forcipata in southern Vietnam. A dichotomous key to identify the 14 Vietnamese species is provided.

Long-term in vitro degradation and in vivo evaluation of resorbable bioceramics.

An essential criterion for the selection of resorbable bioceramics is their ability to degrade inside human body within a reasonable time frame. Furthermore, if the bioceramic can release beneficial ions, such as strontium, as it degrades, recovery time might be shortened. The present study demonstrates that strontium-containing calcium sulfate (Sr,Ca)SO4 can fulfill these criteria. A long-term in vitro degradation analysis for 12 weeks using sintered (Sr,Ca)SO4 discs in phosphate buffered solution (PBS) was conducted. The sintered (Sr,Ca)SO4 disc was then implanted into defects in the distal femur of rats. The degradation rate of (Sr,Ca)SO4 discs showed a strong dependence on the Sr content. Similar results were observed between the long-term in vitro degradation analysis and the in vivo evaluation. The sintered (3.8%Sr,Ca)SO4 disc lost more than 80% of its initial weight after soaking in PBS with shaking at 37 °C for 12 weeks. After 12 weeks in vivo, the remaining volume of the (3.8%Sr,Ca)SO4 disc within the bone defect was ~25%. Over the same time period, new bone was formed at a relative volume of 40%. This study demonstrates the potential of (Sr,Ca)SO4 bioceramic, and the benefits of using a long-term degradation test during the evaluation of resorbable bioceramics.

A head-to-head comparison of the degradation rate of resorbable bioceramics.

Resorbable bioceramics offer advantages in healing bone defects due to their degradation capability. Degradation rates differ significantly from one bioceramic to another; nevertheless, the degradation rate should match the growth rate of new bone. In the present study, a head-to-head comparison of the degradation rate of calcium sulfate and tricalcium phosphate is conducted. First, the degradation behaviors of calcium sulfate and tricalcium phosphate are evaluated separately. The comparison indicates that the degradation rate of calcium sulfate is one order of magnitude faster than that of tricalcium phosphate. Along with a fast degradation rate, the formation of calcium phosphate on the surface of calcium sulfate pellets is also faster. A core-shell roll composed of a calcium sulfate core and a tricalcium phosphate shell is also prepared. After soaking the core-shell roll in phosphate buffered saline solution for 24 h, calcium phosphate precipitates form only on the surface of core, the part containing calcium sulfate anhydrite.

Manipulation of the degradation behavior of calcium sulfate by the addition of bioglass.

A bioactive calcium sulfate/glass composite was prepared using a sintering technique, and Ca-P-Si glass particles were prepared by spray pyrolysis. The glass exhibited bioactivity in terms of its ability to form apatite in a simulated body fluid. The glass was transformed into two crystallized phases, i.e., calcium phosphate and calcium silicate, respectively, during the heating stage. The presence of the crystallized phases retarded the densification of calcium sulfate. A high sintering temperature of 1200 °C was needed to prepare the composite. The increased addition of glass enhanced the strength and decreases the degradation rate of calcium sulfate. The new composite is not only degradable but also bioactive.

The Synonymy of the Supratidal Crab Species Parasesarma cognatum Rahayu & Li, 2013 with P. liho Koller, Liu & Schubart, 2010 (Decapoda: Brachyura: Sesarmidae) Based on Morphological and Molecular Evidence, with a Note on P. paucitorum Rahayu & Ng, 2009.

Parasesarma liho Koller, Liu & Schubart, 2010 and P. cognatum Rahayu & Li, 2013 from East and Southeast Asia are similar species that have been confused in several studies. Here, we re-examined the type specimens of both species and found identical main characters, which is supported by the molecular identity of the mitochondrial cytochrome oxidase subunit I gene. As a result, we treat P. cognatum as a junior subjective synonym of P. liho. We also show that the male paratype of P. paucitorum Rahayu & Ng, 2009 is conspecific with P. liho, although P. paucitorum s. str. remains a distinct but allied species. The distribution of P. liho is updated to include Japan (Ryukyus), Taiwan, Philippines (Cebu) and Indonesia (Sulawesi).

Peroxinectin gene transcription of the giant freshwater prawn Macrobrachium rosenbergii under intrinsic, immunostimulant, and chemotherapeutant influences.

Peroxinectin (PE) gene expressions were determined using real-time PCR in the giant freshwater prawn Macrobrachium rosenbergii based on moulting; prawns were fed diets containing different concentrations of sodium alginate, and were exposed to different concentrations of copper sulphate, benzalkonium chloride (BKC), and trichlorfon. Results showed that PE mRNA expression of prawns was the highest in stage A, significantly decreased in stage B, and reached the lowest level in stages D0/D1. The PE transcript was significantly higher in prawns fed the 1.0 gkg(-1) sodium alginate-containing diet than those fed the 2.0 gkg(-1) sodium alginate-containing diet and those fed the control diet. PE transcripts significantly decreased in prawns exposed to 0.1-0.4 mgL(-1) copper sulphate after 96 h, 0.3-1.0 mgL(-1) BKC after 96 h, and 0.2-0.4 mgL(-1) trichlorfon after 48 h. It was concluded that the status of PE gene expression was seriously affected by the moult cycle, immunostimulant, and chemotherapeutants.