The role of rice fields, fish ponds and water canals for transmission of fish-borne zoonotic trematodes in aquaculture ponds in Nam Dinh Province, Vietnam

BACKGROUND: Fish-borne zoonotic trematodes (FZT), such as Clonorchis sinensis, Opistorchis viverini (Opisthorchiidae) and intestinal trematodes of the family Heterophyidae, constitute a public health hazard in Vietnam and infections with these trematodes has been linked to consumption of raw or undercooked fish from aquaculture. The FZT transmission pathways, however, are more complicated than just the presence of intermediate snail hosts in aquaculture ponds as ponds may exchange water with surrounding habitats such as rice fields and irrigation canals and thereby these surrounding habitats may be a source of snails and cercariae and contribute to FZT infection in cultured fish. METHODS: This is a longitudinal descriptive study on selected farms (n = 30) in Nam Dinh Province which is endemic for FZT. At each farm, we sampled one pond, a small irrigation canal used to supply the pond with water, and a nearby rice field. At each of these three sites, we estimated the density of the FZT intermediate snail hosts and determined their trematode infection status. Comparative analysis was performed for the prevalence and density of FZT infections in fish and snails. RESULTS: Species of the Thiaridae, and most notably Melanoides tuberculata, the most important host species for FZT belonging to the Heterophyidae, were particularly abundant in ponds and small canals, i.e. M. tuberculata was found in 27 ponds and 13 small canals. Bithynia fuchsiana, a potential host for both Heterophyidae and Opisthorchiidae, was rarely found in fish ponds but common in rice fields. A total of 12 types of cercariae were found in the snails and pleurolophocercous cercariae, primarily FZT, constituted about 40 % of all cercarial infections. The fish species cultured were mainly carp species and Haplorchis pumilio was the dominating trematode species infecting fish. Clonorchis spp. were not recorded in any of the ponds. FZT transmission to fish was intense during the summer period (May-June to November) but less intense during the winter months (December-January) partly because cercarial emergence ceases due to the low temperature. CONCLUSION: Our findings highlight the complexity of FZT transmission within aquaculture farm settings and suggest that efforts to control these infections must take a holistic approach using interventions against all stages of the transmission cycle

Variability in the Composition of Pacific Oyster Microbiomes Across Oyster Families Exhibiting Different Levels of Susceptibility to OsHV-1 μvar Disease

Oyster diseases are a major impediment to the profitability and growth of the oyster aquaculture industry. In recent years, geographically widespread outbreaks of disease caused by ostreid herpesvirus-1 microvariant (OsHV-1 μvar) have led to mass mortalities among Crassostrea gigas, the Pacific Oyster. Attempts to minimize the impact of this disease have been largely focused on breeding programs, and although these have shown some success in producing oyster families with reduced mortality, the mechanism(s) behind this protection is poorly understood. One possible factor is modification of the C. gigas microbiome. To explore how breeding for resistance to OsHV-1 μvar affects the oyster microbiome, we used 16S rRNA amplicon sequencing to characterize the bacterial communities associated with 35 C. gigas families, incorporating oysters with different levels of susceptibility to OsHV-1 μvar disease. The microbiomes of disease-susceptible families were significantly different to the microbiomes of disease-resistant families. OTUs assigned to the Photobacterium, Vibrio, Aliivibrio, Streptococcus, and Roseovarius genera were associated with low disease resistance. In partial support of this finding, qPCR identified a statistically significant increase of Vibrio-specific 16S rRNA gene copies in the low disease resistance families, possibly indicative of a reduced host immune response to these pathogens. In addition to these results, examination of the core microbiome revealed that each family possessed a small core community, with OTUs assigned to the Winogradskyella genus and the Bradyrhizobiaceae family consistent members across most disease-resistant families. This study examines patterns in the microbiome of oyster families exhibiting differing levels of OsHV-1 μvar disease resistance and reveals some key bacterial taxa that may provide a protective or detrimental role in OsHV-1 μvar disease outbreaks

Direct Observation of Exceptional Points in Photonic Crystal by Cross-Polarization Imaging in Momentum Space

This study explores exceptional points (EPs) in photonic crystals (PhCs) and introduces a novel method for their single-shot observation. Exceptional points are spectral singularities found in non-Hermitian systems, such as leaky PhC slabs. However, directly observing EPs in PhC systems using regular reflectivity spectroscopy is a considerable challenge due to interference between guided resonances and background signals. In this work, we present a simple, nondestructive technique that employs crossed polarizations to directly observe EPs in momentum-resolved resonant scattering. This approach effectively suppresses the background signal, enabling exclusive probing of the guided resonances where EPs manifest. Our results demonstrate the formation of EPs in both energy-momentum mapping and isofrequency imaging. All experimental findings align seamlessly with numerical simulations and analytical models. Our approach holds great potential as a robust tool for studying non-Hermitian physics in PhC platform

Simulation for Optimizing the Design of Cryogenic Stopping Cell for the IGISOL Facility at ELI-NP

The production of the exotic neutron-rich ion beams from photofission of the actinide targets in an IGISOL facility will be studied via an experimental program that will take place at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility. Geant4 simulation toolkit was used for optimizing the target configuration in order to maximize the rate of released photofission fragments from targets placed in a cell filled with He gas

Farm-Level Risk Factors for Fish-Borne Zoonotic Trematode Infection in Integrated Small-Scale Fish Farms in Northern Vietnam

BACKGROUND: Northern Vietnam is an endemic region for fish-borne zoonotic trematodes (FZT), including liver and intestinal flukes. Humans acquire the FZT infection by eating raw or inadequately cooked fish. The production of FZT-free fish in aquaculture is a key component in establishing a sustainable program to prevent and control the FZT transmission to humans. Interventions in aquaculture should be based on knowledge of the main risk factors associated with FZT transmission. METHODOLOGY/PRINCIPAL FINDINGS: A longitudinal study was carried out from June 2006 to May 2007 in Nam Dinh province, Red River Delta to investigate the development and risk factors of FZT infections in freshwater cultured fish. A total of 3820 fish were sampled six times at two-month intervals from 96 fish farms. Logistic analysis with repeated measurements was used to evaluate potential risk factors based on information collected through questionnaire interviews with 61 fish farm owners. The results showed that the FZT infections significantly increased from first sampling in June to July 2006 (65%) to sixth sampling in April to May, 2007 (76%). The liver fluke, Clonorchis sinensis and different zoonotic intestinal flukes including Haplochis pumilio, H. taichui, H. yokogawai, Centrocestus formosanus and Procerovum varium were found in sampled fish. Duration of fish cultured (sampling times), mebendazole drug self-medication of household members, presence of snails in the pond, and feeding fish with green vegetation collected outside fish farms all had a significant effect on the development of FZT prevalence in the fish. CONCLUSIONS/SIGNIFICANCE: The FZT prevalence in fish increased by 11 percentage points during a one-year culture period and the risk factors for the development of infection were identified. Results also highlight that the young fish are already highly infected when stocked into the grow-out systems. This knowledge should be incorporated into control programs of FZT transmission in integrated small-scale aquaculture nursery and grow-out systems in Vietnam

Surveillance and treatment of primary hepatocellular carcinoma (aka. STOP HCC): protocol for a prospective cohort study of high-risk patients for HCC using GALAD-score.

Vietnam and Saudi Arabia have high disease burden of primary hepatocellular carcinoma (HCC). Early detection in asymptomatic patients at risk for HCC is a strategy to improve survival outcomes in HCC management. GALAD score, a serum-based panel, has demonstrated promising clinical utility in HCC management. However, in order to ascertain its potential role in the surveillance of the early detection of HCC, GALAD needs to be validated prospectively for clinical surveillance of HCC (i.e., phase IV biomarker validation study). Thus, we propose to conduct a phase IV biomarker validation study to prospectively survey a cohort of patients with advanced fibrosis or compensated cirrhosis, irrespective of etiologies, using semi-annual abdominal ultrasound and GALAD score for five years. We plan to recruit a cohort of 1,600 patients, male or female, with advanced fibrosis or cirrhosis (i.e., F3 or F4) and MELD ≤ 15, in Vietnam and Saudi Arabia (n = 800 each). Individuals with a liver mass ≥ 1 cm in diameter, elevated alpha-fetoprotein (AFP) (≥ 9 ng/mL), and/or elevated GALAD score (≥ -0.63) will be scanned with dynamic contrast-enhanced magnetic resonance imaging (MRI), and a diagnosis of HCC will be made by Liver Imaging Reporting and Data System (LiRADS) assessment (LiRADS-5). Additionally, those who do not exhibit abnormal imaging findings, elevated AFP titer, and/or elevated GALAD score will obtain a dynamic contrast-enhanced MRI annually for five years to assess for HCC. Only MRI nearest to the time of GALAD score measurement, ultrasound and/or AFP evaluation will be included in the diagnostic validation analysis. MRI will be replaced with an abdominal computed tomography scan when MRI results are poor due to patient conditions such as movement etc. Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced MRI will not be carried out in study sites in both countries. Bootstrap resampling technique will be used to account for repeated measures to estimate standard errors and confidence intervals. Additionally, we will use the Cox proportional hazards regression model with covariates tailored to the hypothesis under investigation for time-to-HCC data as predicted by time-varying biomarker data. The present work will evaluate the performance of GALAD score in early detection of liver cancer. Furthermore, by leveraging the prospective cohort, we will establish a biorepository of longitudinally collected biospecimens from patients with advanced fibrosis or cirrhosis to be used as a reference set for future research in early detection of HCC in the two countries. Name of the registry: ClinicalTrials.gov Registration date: 22 April 2022 Trial registration number: NCT05342350 URL of trial registry record

Characterisation of the Sydney Rock Oyster microbiota and its association with QX disease

University of Technology Sydney. Faculty of Science.The Sydney rock oyster (SRO; ) is native to Australia and is the most intensively farmed oyster species in the country. However, diseases such as Queensland unknown (QX) disease have caused substantial losses and impeded productivity. The aetiological agent of QX disease is the parasite causing disease seasonally, generally in the late summer and early autumn. QX infection initiates at the palps and gills before migrating into the digestive gland where sporulation occurs causing blockage and eventual starvation and death in the oyster. Emerging evidence suggests that QX disease outbreaks are driven by a series of complex environmental and host factors such as salinity and oyster genetics. To mitigate the impacts of QX disease, the New South Wales Department of Primary Industries (NSW DPI) has led a selective breeding program using both mass selection methods and family-based breeding to create lines that are resistant. Some families have shown approximately 85% survival through one cycle of disease however, the mechanisms that drive this resistance are poorly understood. One potential factor influencing QX disease resistance is the microbiota which is investigated in this thesis. In other oyster species, the microbiota is emerging as a key factor in disease dynamics and studies have begun to unravel the environmental factors that influence its structure such as location, season, genetics and disease state. For the SRO, there is a paucity of studies examining the microbiota and the factors that influence the SRO microbiota composition. Therefore, this thesis aimed to explore the influence of geographic location, season (comparing summer and winter) and genetics (selectively bred SROs with a range of resistance to QX disease) on the SRO microbiota (Chapter 2). It also investigated microbiota dynamics prior to and during a QX disease event (Chapter 3) and, compared the SRO microbiota across families for identifying taxa that could be used as indicators for healthy and QX-infected oysters (Chapter 4). Overall, this thesis provides new knowledge of the SRO microbiota and the factors that influence the SRO microbiota assemblage and contributes valuable information on how the SRO microbiota shifts during a QX disease event and identifies putative key taxa that may be important for health and disease states and/or good indicator taxa of these states. A better understanding of the SRO microbiota, its potential involvement in health and disease may enable effective disease prevention in the future

Chemical constituents and cytotoxicity of Aspidistra letreae

A phytochemical investigation of whole Aspidistra letreae plants led to the isolation of 2H-chromen-2-one (1), α-tocopherol (2), (E)-phytol (3), asparenydiol (4) and (25S)-spirost-1β,3α,5β-triol (5). Their structures were determined on the basis of NMR spectral evidences and in comparison with the reported data. Of these, asparenydiol (4) was isolated from the genus Aspidistra for the first time. This is also the first report on the separation and structural determination of (25S)-spirost-1β,3α,5β-triol (5) as a pure compound. The methanol extract from the whole plants of Aspidistra letreae exhibits moderate cytotoxicity against the LU-1, HeLa, MDA-MB-231, Hep-G2, and MKN-7 human cancer cell lines with IC50 values ranging from 52.58 ± 3.65 to 64.78 ± 4.89 μg/mL

Mortality prognosis of NGAL, NTproBNP, hsTnT, and GRACE score in patients with acute coronary syndrome

Background: NGAL serum concentration have predictive value for cardiovascular events and mortality in patients with acute coronary syndrome (ACS). Objectives: Assessed the all-cause mortarlity prognosis value of serum neutrophil gelatinase-associated lipocalin (NGAL), combination with N-terminal pro B-type natriuretic peptide (NT-proBNP), and hsTnT, and GRACE score in patients with ACS. Materials and methods: We conducted a cross-sectional analysis study used in this study in 58 patients with ACS. Serum NGAL, NT-proBNP, hs-TnT concentration and GRACE score associated with death events (after 3 months of follow-up) were assessed by receiver operating characteristic (ROC) curve. Results: High performance in predicting mortality of NGAL with a cut-off value of 154.55 ng/mL (AUC, 95% CI = 0.96, 0.90 – 1.0; p = 0.001), GRACE score with 140.50 scores (AUC, 95% CI = 0.76, 0.57 – 0.96; p = 0.051). Combination of NTproBNP plus NGAL indicated with the highest value (AUC, 95% CI = 0.96, 0.91 – 1.0; Se = 80.0; Sp = 92.5; p = 0.001). The relative risk assessment indicated a high value in mortality prediction of NGAL with a cut-off value of 154.55 (OR, 95% CI = 49.0, 4.3 – 549.2; p < 0.001), and GRACE score with 140.50 scores (OR, 95% CI = 11.1, 1.1 – 108.4; p = 0.013). Conclusion: NGAL can be employed as a biomarker for the early prediction of mortality events in individuals with ACS. The combination of NGAL, NT-proBNP, hsTnT, and GRACE score showed the higher outcome but not worth mentioning