Conducted in subtropical coastal waters of eastern Hong Kong, this study provides information on species compositions of juvenile fish communities in several mangrove and non-mangrove habitats, and ...evaluated the influences of water temperature, salinity, turbidity, sediment organic matter (SOM), water depth, and sediment grain size on fish assemblages. In total, 85,427 fish belonging to 76 species from more than 29 families were collected. Fish densities were higher in mangrove mudflats than in non-mangrove habitats, but only a few of the dominant species were significantly more abundant in mangrove than in non-mangrove habitats. Fish assemblages in mangrove and non-mangrove mudflats were quite similar. Fish compositions were influenced by environmental factors including the SOM and water depth, but not by the presence of mangroves. The present study suggests that the nursery function of mangroves is both site- and species-specific. Compared to shallow mudflats with and without mangroves, deep-water sandy beaches may be less suitable for juvenile fish because of their low SOM content and high piscivorous fish abundances. More studies need to be conducted before definitive conclusions can be made on the nursery function of mangroves in Hong Kong and subtropical Asia.
Studies have suggested that patients with chronic hepatitis B, either co- or superinfected, have more aggressive liver disease progression than those with the HDV. This systematic literature review ...and meta-analysis examined whether HDV RNA status is associated with increased risk of advanced liver disease events in patients who are HBsAg and HDV antibody positive.
A total of 12 publications were included. Relative rates of progression to advanced liver disease event for HDV RNA+/detectable versus HDV RNA-/undetectable were extracted for analysis. Reported OR and HRs with 95% CI were pooled using the Hartung-Knapp-Sidik-Jonkman method for random-effects models. The presence of HDV RNA+ was associated with an increased risk of any advanced liver disease event random effect (95% CI): risk ratio: 1.48 (0.93, 2.33); HR: 2.62 (1.55, 4.44). When compared to the patients with HDV RNA- status, HDV RNA+ was associated with a significantly higher risk of progressing to compensated cirrhosis risk ratio: 1.74 (1.24, 2.45) decompensated cirrhosis HR: 3.82 (1.60, 9.10), HCC HR: 2.97 (1.87, 4.70), liver transplantation HR: 7.07 (1.61, 30.99), and liver-related mortality HR: 3.78 (2.18, 6.56).
The patients with HDV RNA+ status have a significantly greater risk of liver disease progression than the patients who are HDV RNA-. These findings highlight the need for improved HDV screening and linkage to treatment to reduce the risk of liver-related morbidity and mortality.
The swimming behavior of males and females of the seldom studied sub-tropical copepod Oncaea venusta was studied using scale-dependent (swimming speed and net-to-gross displacement ratio) and ...scale-independent (fractal dimension) metrics. The scale-dependent metrics were characterized by: (1) a considerable intra- and inter-individual variability that prevented the identification of any specific behavior and (2) a strong dependence on the number of data points available in each individual path. Conversely, the scale-independent metric (fractal dimensional) resolved reduced intra- and inter-individual variability and independence from the length of the swimming paths, leading to the identification of 4 groups of distinct swimming patterns. While additional behavioral experiments are needed to ensure the relevance and the generality of the present results, behavioral fractal analysis nevertheless demonstrates a promising ability to elucidate the complexity of zooplankton behavior.
HDV leads to the most severe form of viral hepatitis; however, the prevalence of HDV is not well understood. Using real-world data from the All-Payer Claims Database, this study estimates the ...prevalence of HBV/HDV infection among the chronic HBV population and describes patient/clinical characteristics for adults with HBV/HDV infection in the United States.
Adults (≥18 years) with ≥1 inpatient claim or ≥2 outpatient claims for HDV infection or HBV in the All-Payer Claims Database from January 1, 2014, to December 31, 2020, were identified. HDV prevalence was calculated as the proportion of patients with HBV/HDV infection among total patients with HBV infection. Patient characteristics, socioeconomic status, advanced liver complications (eg, cirrhosis, HCC), and comorbidities were assessed. A total of 6719 patients were diagnosed with HBV/HDV among 144,975 with HBV and 12 months of continuous data, for a prevalence of 4.6%. At diagnosis, 31.7% of patients with HBV/HDV had advanced liver complications, including compensated cirrhosis (16.3%) and decompensated cirrhosis (10.4%). Diabetes (50.5%), hypertension (49.8%), and HIV infection (30.9%) were the top 3 comorbidities.
In a large database capturing approximately 80% of the US-insured population, HBV/HDV infection prevalence was 4.6% among adults infected with HBV. Patients infected with HDV had high rates of baseline liver complications and other comorbidities at the time of diagnosis, suggesting potentially delayed diagnosis and/or treatment. Earlier identification of HBV/HDV infection among the population with HBV may provide opportunities to improve linkage to care and treatment, thereby reducing the risk of liver-related morbidity and mortality.
Picoeukaryotes (<2 to 3 km) are important components of aquatic ecosystems. The genetic diversity and seasonal variability of marine picoeukaryotes were compared between a semi-enclosed harbour and ...the adjacent open sea off the subtropical coast in the western Pacific Ocean based on 18S rRNA clone library analysis. Examination of 733 clones revealed 186 different restriction fragment length polymorphism (RFLP) patterns, representing 186 operational taxonomic units (OTUs). At least 19 high-level taxonomic groups of picoeukaryotes were recorded. Alveolates group II, ciliates and stramenopiles comprising 37, 17 and 11% of the picoeukaryotes, respectively, were the most dominant groups. Phototrophs such as prasinophytes, cryptophytes and haptophytes were retrieved occasionally. Members from the 2 newly defined phyla, picobiliphytes and Telonemia, were also obtained. A differential spatial distribution of OTUs was observed between samples collected from the 2 sampling sites. Seasonal variations in picoeukaryote composition were more pronounced in the open sea libraries than in the semi- enclosed harbour libraries.
Spatial and seasonal characteristics of phytoplankton in Tolo Harbour, Hong Kong, were studied by microscopic observation of phytoplankton samples and HPLC analysis of chemotaxonomic pigments. ...Diatoms dominated the phytoplankton. Common diatoms included Skeletonema costatum and species of Cerataulina, Leptocylindrus, Pseudo-nitzschia and Thalassiosira. Dinoflagellates occurred sporadically and mainly in the inner part of the harbour. The dinoflagellate Scrippsiella trochoidea was the causative organism for the red tide occurrences in March, April and September 2001. Significant positive correlations between fucoxanthin and diatoms and between peridinin and dinoflagellates suggested that fucoxanthin and peridinin were valuable chemotaxonomic markers for diatoms and dinoflagellates, respectively. Analysis of pigment ratios revealed that red tide events caused by dinoflagellates were marked by increase in the value of PERI:chl a and decrease in the value of FUCO:chl a. Increase in the value of FUCO:chl a also revealed the presence of a dense population of Pseudo-nitzschia that was not indicated by increase in chlorophyll a and fucoxanthin concentrations. Pigment analysis also revealed the presence of cyanobacteria, silicoflagellates, cryptophytes and green algae in the surface waters of Tolo Harbour.
A bloom of the dinoflagellate
Scrippsiella trochoidea
was detected for the first time in inner Tolo Harbor, Hong Kong in 2 000. Water samples were collected at eight stations along a transect passing ...through a red tide patch for microscopic analysis of phytoplankton composition and high-performance liquid chromatography (HPLC) analysis of phytoplankton pigments. During the bloom, the density of dinoflagellates was 1.1×10
6
cells L
−1
within the patch and 8.6×10
5
cells L
−1
outside the patch where the phytoplankton community was dominated by diatoms. After the bloom the
S. trochoidea
began to decrease in density and was replaced by diatoms as the dominating bloom-causing organisms at all stations, and the density of dinoflagellates at most stations was less than 1.0 × 10
6
cells L
−1
. The status of
S. trochoidea
as the causative species of the bloom was indicated by the presence of peridinin, the marker pigment for dinoflagellates. The shift from dinoflagellates to diatoms was marked by the decline of peridinin and the prevalence of fucoxanthin. Phytoplankton pigment markers also revealed the presence of other minor phytoplankton assemblages such as cryptomonads and blue-green algal.
Shallow-water hydrothermal vents (HTVs) are an ecologically important habitat with a geographic origin similar to that of deep-sea HTVs. Studies on shallow-water HTVs have not only facilitated ...understanding of the influences of vents on local ecosystems but also helped to extend the knowledge on deep-sea vents. In this study, the diversity of bacterial communities in the sediments of shallow-water HTVs off Kueishan Island, Taiwan, was investigated by examining the 16S ribosomal RNA gene as well as key functional genes involved in chemoautotrophic carbon fixation (aclB, cbbL and cbbM). In the vent area, Sulfurovum and Sulfurimonas of Epsilonproteobacteria appeared to dominate the benthic bacterial community. Results of aclB gene analysis also suggested involvement of these bacteria in carbon fixation using the reductive tricarboxylic acid (rTCA) cycle. Analysis of the cbbM gene showed that Alphaproteobac terial members such as the purple non-sulfur bacteria were the major chemoautotrophic bacteria involving in carbon fixation via the Calvin–Benson–Bassham (CBB) cycle. However, they only accounted for <2% of the total bacterial community in the vent area. These findings suggest that the rTCA cycle is the major chemoautotrophic carbon fixation pathway in sediments of the shallow-water HTVs off Kueishan Island.
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