18 research outputs found
Transient or permanent inhabitants : cultured internal microbiota of Cichlidogyrus thurstonae and Scutogyrus longicornis (Monogenea: Ancyrocephalidae) from Oreochromis sp.
Monogeneans, a class of parasitic platyhelminthes, are usually found on the surface of fish. When it feeds on its host, it
harbours bacteria, which can survive in its gut. Occasionally, the monogeneans may cause damages on fish tissue while
feeding and may allow secondary infection. The present study aimed to isolate and identify culturable bacteria obtained
within the gill monogeneans, Cichlidogyrus thurstonae and Scutogyrus longicornis, and gill surface of the tilapia fish,
Oreochromis sp. based on 16S ribosomal RNA gene sequencing. Monogeneans were isolated from the fish gill filaments
and surface disinfected using 70% ethanol before squashed aseptically on Luria Bertani (LB) agar to isolate the internal
microbiota. A total of five bacteria species, namely Burkholderia sp., En terobacter h o rmaechei, Enterobacter sp.,
Ochrobactrum intermedium and Pantoea sp., were found within C. thurstonae, whilst a total of eight bacteria species,
namely Burkholderia contaminans, Pantoea dispersa, Sphingomonas yabuuchiae, Rhizobium pusense, O. intermedium,
Acinetobacter bereziniae, Escherichia hermannii, and Staphylococcus saprophyticus, were found within S. longicornis
in which B. contaminans, P. dispersa, and S. yabuuchiae were also found on the surface of the tilapia fish gill filaments.
Enterobacter bugandensis and Acinetobacter pittii were found solely on the surface of the gill filaments. These bacteria
are also found in the environment and some of them are believed to be pathogenic to fish. We suggest that monogeneans
may serve as potential bacteria reservoirs, which facilitate the transmission of bacteria
Determinants of methicillin-resistant Staphylococcus aureus (MRSA) prevalence in the Asia-Pacific region: A systematic review and meta-analysis.
OBJECTIVES: Published literature on methicillin-resistant Staphylococcus aureus (MRSA) in the Asia-Pacific region was reviewed to document the prevalence of MRSA in the region and to examine the impact of variability in study design on the reported MRSA prevalence data. METHODS: This review included studies reporting MRSA prevalence between 2000 and 2016. Studies were excluded if they did not contain complete information on antimicrobial susceptibility testing (AST) methods. Primary outcomes were the proportion of MRSA among S. aureus isolates (resistance proportion) or among individual samples (prevalence). RESULTS: A total of 229 studies in 19 countries/territories were included in the study. There was substantial heterogeneity in both outcomes (resistance proportion, I2=99.59%; prevalence, I2=99.83%), precluding pooled averages, and meta-regression analyses revealed that these variations were explained by country income status and participant characteristics but not by methodological differences in AST. Also, no significant secular changes in MRSA prevalence or resistance proportions in Asia-Pacific were found. CONCLUSION: The resistance proportions and prevalence of MRSA infections in Asia-Pacific are comparable with those reported in other regions with no significant secular changes in the past decade. Country income status and characteristics of the sample population explained more variation in the reported resistance proportions and prevalence of MRSA than methodological differences in AST across locations in the region
Ultrastructure of head organs (anterior adhesive apparatus) and posterior secretory systems of Caballeria liewi Lim, 1995 (Monogenea, Ancyrocephalidae)
A Framework for Managing Knowledge in Strategic Alliances in the Biotechnology Sector
Biotechnology is a rapidly expanding field of science that has led to the formation of a large number of companies that together form a significant sector within the Australian economy. Even though there has been considerable growth in the Australian biotechnology sector as a whole, a large percentage of Australian biotechnology firms are small and medium sized enterprises (SMEs) that suffer from a lack of funding and expertise. The development and management of effective strategic alliances are critical to the success and development of biotechnology firms as they provide opportunities to share resources and expertise, access funding and develop new ideas. However, developing and managing strategic alliances is fraught with difficulties which are compounded by size and resource asymmetries and the nature of the biotechnology market. In this paper, we identify the difficulties faced by biotechnology firms and examine the importance of knowledge management related to alliance formation and development with special reference to the Australian context. We examine the knowledge and expertise that are required to be effective in developing strategic alliances in the biotechnology sector and provide a framework for managing knowledge related to strategic alliances. We suggest that critical systems approaches, in particular creative holism, are needed to manage the various forms of knowledge associated with strategic alliances
The NLRP3 Inflammasome May Contribute to Pathologic Neovascularization in the Advanced Stages of Diabetic Retinopathy
Diabetic retinopathy (DR) is a retinal microvascular disease characterized by inflammatory and angiogenic pathways. In this study, we evaluated NLRP3 inflammasome in a double transgenic mouse model, Akimba (Ins2 Akita xVEGF+/-), which demonstrates hyperglycemia, vascular hyperpermeability and neovascularization seen in the proliferative DR. Retinal structural integrity, vascular leakage and function were examined by fundus photography, fluorescein angiography, optical coherence tomography, retinal flat mounts, laser speckle flowgraphy (LSFG), and electroretinography in Akimba and its parental strains, Akita (Ins2 Akita ) and Kimba (trVEGF029) mice. Inflammatory mechanisms involving NLRP3 inflammasome were investigated using real time-PCR, immunohistochemistry, ELISA and western blots. We observed an increased vascular leakage, reduced retinal thickness, and function in Akimba retina. Also, Akimba retina depicts decreased relative flow volume measured by LSFG. Most importantly, high levels of IL-1β along with increased NLRP3, ASC, and Caspase-1 at mRNA and protein levels were observed in Akimba retina. However, the in vivo functional role remains undefined. In conclusion, increased activation of macroglia (GFAP), microglia (Iba-1 and OX-42) and perivascular macrophages (F4/80 and CD14) together with pro-inflammatory (IL-1β and IL-6) and pro-angiogenic markers (PECAM-1, ICAM-1, VEGF, Flt-1, and Flk-1), suggested a critical role for NLRP3 inflammasome in the Akimba mouse model depicting advanced stages of DR pathogenesis
Ultrastructure of head organs (anterior adhesive apparatus) and posterior secretory systems of Caballeria liewi Lim, 1995 (Monogenea, Ancyrocephalidae)
Caballeria liewi Lim, 1995, uses adhesive secretions from the head organs and posterior secretory systems to assist in locomotion and attachment. Ultrastructural investigations show that the head organs of C. liewi consist of three pairs of antero-lateral pit-like openings bearing microvilli and ducts leading from two types of uninucleated gland cells (located lateral to the pharynx), one type producing rod-like (S1) bodies with an electron-dense matrix containing less electron-dense vesicles and the second type producing oval (S2) bodies with a homogeneous electron-dense matrix. Interlinking band-like structures are observed between S1 bodies and between S2 bodies. S1 body is synthesised in the granular endoplasmic reticulum, transported to a Golgi complex to be packaged into vesicles and routed into ducts for exudation. The synthesis of the S2 body is unresolved. Haptoral secretions manifested externally as net-like structures are derived from dual electron-dense (DED) secretory body produced in the peduncular gland cells. The DED body consists of a less electron-dense oval core in a homogeneous electron-dense matrix. On exocytosis into the pyriform haptoral reservoir, DED bodies are transformed into a secretion with two types of inclusions (less electron-dense oval and electron-dense spherical inclusions) in an electron-dense matrix. The secretions are further transformed (as small, oval, electron-dense bodies) when transported to the superficial anchor grooves, and on exudation into the gill tissues, the secretions become an electron-dense matrix. Secretory bodies associated with uniciliated structures, anchor sleeves and marginal hooks are also observed.</p
Analysis of clinically relevant variants from ancestrally diverse Asian genomes
Asian populations are under-represented in human genomics research. Here, we characterize clinically significant genetic variation in 9051 genomes representing East Asian, South Asian, and severely under-represented Austronesian-speaking Southeast Asian ancestries. We observe disparate genetic risk burden attributable to ancestry-specific recurrent variants and identify individuals with variants specific to ancestries discordant to their self-reported ethnicity, mostly due to cryptic admixture. About 27% of severe recessive disorder genes with appreciable carrier frequencies in Asians are missed by carrier screening panels, and we estimate 0.5% Asian couples at-risk of having an affected child. Prevalence of medically-actionable variant carriers is 3.4% and a further 1.6% harbour variants with potential for pathogenic classification upon additional clinical/experimental evidence. We profile 23 pharmacogenes with high-confidence gene-drug associations and find 22.4% of Asians at-risk of Centers for Disease Control and Prevention Tier 1 genetic conditions concurrently harbour pharmacogenetic variants with actionable phenotypes, highlighting the benefits of pre-emptive pharmacogenomics. Our findings illuminate the diversity in genetic disease epidemiology and opportunities for precision medicine for a large, diverse Asian population.</p