Latest research on acute hepatopancreatic necrosis disease (AHPND) of penaeid shrimps

Acute hepatopancreatic necrosis disease (AHPND) is caused by unique strains of Vibrio parahaemolyticus (VPAHPND) and V. harveyi that have transferrable plasmid carrying the virulent PirAB-like toxin genes. The genomes of VPAHPND strains and V. harveyi from Thailand and Viet Nam, respectively, have been characterized by our group. The genome of VPAHPND strains from Mexico, Viet Nam, and China have also been studied by other groups. We have developed a conventional polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) methods for the detection of AHPND using a primer set that targets the PirAB-like toxin genes of VPAHPND. We have characterized the toxin genes of VPAHPND strains and also constructed a recombinant plasmid (broad host range) carrying PirAB-like toxin genes. Non-VPAHPND strain N7 which does not carry the plasmid and strain FP11 which is carrying a plasmid not coding for the toxin genes were transformed with the plasmid carrying PirAB-like toxin genes. As a result, the transformed N7 and FP11 strains became virulent and killed whiteleg shrimp (Penaeus vannamei) similar to or at par with the virulence of VPAHPND strain. We then fed the whiteleg shrimp with commercial feed containing the formalin-killed VPAHPND strain. After 2 days of feeding, all of the whiteleg shrimp died. These results clearly indicate that the PirAB-like toxin is the virulence factor of VPAHPND. We have been investigating the virulence mechanism of the PirAB-like toxin produced by VPAHPND strains. First, we calculated the copy number of plasmid encoding the PirAB-like toxin genes of several VPAHPND strains. The copy number of the plasmid varied, ranging from 1 to 36 copies. Interestingly, VPAHPND strains carrying low copy number of plasmid were more virulent than VPAHPND strains carrying high copy number of the plasmid. These results imply that the copy number of toxin genes is not an important factor responsible for the degree of virulence of the VPAHPND strains. We are also studying other factors associated with the virulence of PirAB-like toxin. Likewise, we are developing prevention methods against AHPND including the use of formalin-killed cell vaccine, IgY additive in feed, and nano-bubble treatment of rearing water. This paper summarizes the current R&D on the disease

Shrimp metabolism: The roles of lactate dehydrogenase (c31), glycogen phosphorylase (c34) and protein kinase (PK) as revealed by RNA interference

Abstract only.Energy metabolism is well-studied in vertebrate systems, providing insights on the genes and mechanisms involved in different pathways necessary for the survival of an organism. Yet, such studies are still lacking in invertebrate systems much more in shrimp. An earlier study has showed several contigs from the black tiger shrimp to be homologous to white spot syndrome virus (WSSV), a devastating pathogen in shrimp, including contig 31-WSSVORF82 (c31) and contig 34-WSSVORF21 (c34). This study aims to unveil the roles of three genes: c31, c34 and protein kinase (PK) in the shrimp system and its possible role in WSSV-infection. Rapid amplification of cDNA ends-polymerase chain reaction or RACE-PCR was used to obtain the full-length sequence of c31 and c34, followed by in vivo gene silencing using RNAi technology, and intramuscularly injecting dsRNA to WSSVchallenged Macrobrachium rosenbergii and Penaeus (Marsupenaeus) japonicus. Gene expression followed for healthy shrimps and dsRNA-treated shrimps. Mrc31 was revealed to be the enzyme lactase dehydrogenase (LDH), commonly released during tissue damage and is a marker for disease. The most parsimonious tree pictured Mrc31 to be sister clades to LDH of other shrimp species, Penaeus monodon and P. vannamei, supported with 100% and 72% bootstrap values, respectively. Mrc34 was highly homologous to the glycogen phosphorylase (GP) enzymes of other organisms including that of another shrimp, M. japonicus, bearing a bootstrap value of 99%. For PK, phylogenetic analysis revealed that the three open reading frames (ORFs) from P. monodon, M. rosenbergii and P. japonicus have 30% homology to WSSV-PK supported by a 98% bootstrap value. Mortality data from dsRNA-treated and WSSV-infected shrimps showed that treatment with dsRNA-LDH, GP and PK had significantly higher survival rates compared to that of the controls, Phosphate Buffered Saline (PBS) and Green Fluorescent Protein (GFP). Silencing the three genes in the shrimp has rendered some protective effect against the virus. Gene expression showed that all three genes are present in immune-related organs such as the gills, hepatopancreas and hemocyte. This study is the first to report the possible identities and functions of contigs 31, 34 and PK providing valuable data on the shrimp's genome

Lactoferrin-like Immunoreactivity in Distinct Neuronal Populations in the Mouse Central Nervous System

Lactoferrin (Lf) is an iron-binding glycoprotein mainly found in exocrine secretions and the secondary granules of neutrophils. In the central nervous system (CNS), expression of the Lf protein has been reported in the lesions of some neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, as well as in the aged brain. Lf is primarily considered an iron chelator, protecting cells from potentially toxic iron or iron-requiring microorganisms. Other biological functions of Lf include immunomodulation and transcriptional regulation. However, the roles of Lf in the CNS have yet to be fully clarified. In this study, we raised an antiserum against mouse Lf and investigated the immunohistochemical localization of Lf-like immunoreactivity (Lf-LI) throughout the CNS of adult mice. Lf-LI was found in some neuronal populations throughout the CNS. Intense labeling was found in neurons in the olfactory systems, hypothalamic nuclei, entorhinal cortex, and a variety of brainstem nuclei. This study provides detailed information on the Lf-LI distribution in the CNS, and the findings should promote further understanding of both the physiological and pathological significance of Lf in the CNS

Development of a finger like multi-joint articulated surgical retractor for use in endoscopic surgery

The authors have developed an articulated medical instrument which assists with the movement of and maintenance of the position of such as a lung during surgery to assist providing improved viewability and providing the necessary space required to work efficiently and effectively. Conventionally holding such as, a lung in a given position is achieved by arranging gauze in an appropriate configuration with the aid of a simple shaft like surgical instrument, however for various reasons the gauze requires constant replacement and rearrangement resulting in significant surgical inefficiency. By using an articulated mechanism that mimics the functionality of fingers, we have developed a surgical device that inherently provides greater mechanical stability and does not require the use of gauze, thus enabling more efficient surgery. The prototyping process was assisted with the use of 3D-CAD to simulate static and dynamic conditions and a 3D-printer to confirm the concept and then a working prototype was created. In order to validate the dynamic functionality of this surgical instrument, it was tested on a porcine lung which closely approximates human lungs by a clinical doctor of thoracic surgery. The result was that the developed prototype articulated mechanism was able to stably move and hold the lung in position during surgery thus confirming the dynamic efficacy of the mechanism

Hyper-expansion of large DNA segments in the genome of kuruma shrimp, Marsupenaeus japonicus

<p>Abstract</p> <p>Background</p> <p>Higher crustaceans (class Malacostraca) represent the most species-rich and morphologically diverse group of non-insect arthropods and many of its members are commercially important. Although the crustacean DNA sequence information is growing exponentially, little is known about the genome organization of Malacostraca. Here, we constructed a bacterial artificial chromosome (BAC) library and performed BAC-end sequencing to provide genomic information for kuruma shrimp (<it>Marsupenaeus japonicus</it>), one of the most widely cultured species among crustaceans, and found the presence of a redundant sequence in the BAC library. We examined the BAC clone that includes the redundant sequence to further analyze its length, copy number and location in the kuruma shrimp genome.</p> <p>Results</p> <p>Mj024A04 BAC clone, which includes one redundant sequence, contained 27 putative genes and seemed to display a normal genomic DNA structure. Notably, of the putative genes, 3 genes encode homologous proteins to the inhibitor of apoptosis protein and 7 genes encode homologous proteins to white spot syndrome virus, a virulent pathogen known to affect crustaceans. Colony hybridization and PCR analysis of 381 BAC clones showed that almost half of the BAC clones maintain DNA segments whose sequences are homologous to the representative BAC clone Mj024A04. The Mj024A04 partial sequence was detected multiple times in the kuruma shrimp nuclear genome with a calculated copy number of at least 100. Microsatellites based BAC genotyping clearly showed that Mj024A04 homologous sequences were cloned from at least 48 different chromosomal loci. The absence of micro-syntenic relationships with the available genomic sequences of <it>Daphnia </it>and <it>Drosophila </it>suggests the uniqueness of these fragments in kuruma shrimp from current arthropod genome sequences.</p> <p>Conclusions</p> <p>Our results demonstrate that hyper-expansion of large DNA segments took place in the kuruma shrimp genome. Although we analyzed only a part of the duplicated DNA segments, our result suggested that it is difficult to analyze the shrimp genome following normal analytical methodology. Hence, it is necessary to avoid repetitive sequence (such as segmental duplications) when studying the other unique structures in the shrimp genome.</p

TGF-β regulates isoform switching of FGF receptors and epithelial–mesenchymal transition

Both TGF-β and FGF signalling regulate the epithelial–mesenchymal transition. Here, TGF-β is found to promote myofibroblast differentiation, while concomitant FGF pathway activation instead drives cells towards an invasive mesenchymal fate

Clinical Outcome of Patients with Pelvic and Retroperitoneal Bone and Soft Tissue Sarcoma : A Retrospective Multicenter Study in Japan

This study aimed to retrospectively analyze the clinical outcomes of patients with pelvic and retroperitoneal bone and soft tissue sarcoma (BSTS). Overall, 187 patients with BSTS in the pelvis and retroperitoneal region treated at 19 specialized sarcoma centers in Japan were included. The prognostic factors related to overall survival (OS), local control (LC), and progression-free survival (PFS) were evaluated. The 3-year OS and LC rates in the 187 patients were 71.7% and 79.1%, respectively. The 3-year PFS in 166 patients without any distant metastases at the time of primary tumor diagnosis was 48.6%. Osteosarcoma showed significantly worse OS and PFS than other sarcomas of the pelvis and retroperitoneum. In the univariate analyses, larger primary tumor size, soft tissue tumor, distant metastasis at the time of primary tumor diagnosis, P2 location, chemotherapy, and osteosarcoma were poor prognostic factors correlated with OS. Larger primary tumor size, higher age, soft tissue tumor, chemotherapy, and osteosarcoma were poor prognostic factors correlated with PFS in patients without any metastasis at the initial presentation. Larger primary tumor size was the only poor prognostic factor correlation with LC. This study has clarified the epidemiology and prognosis of patients with pelvic and retroperitoneal BSTS in Japan

Development and research of the application that support recording and transmittting activities of disasters

We developed an assistant tool which adopted AR technology, for town walk activity in a disaster area. We have developed the tool with the aim both to know clearly the past and to pass down stories of the disaster from generation to generation