Beneath the surface: DNA barcoding of shark fins in Singapore.

The global decline of shark populations, largely driven by overfishing to supply the shark fin trade, poses a significant threat to marine ecosystems. Southeast Asia, and particularly Singapore, is a key hub for the transit and trade of shark fins that contribute to the exploitation of these apex predators. Through the use of DNA barcoding techniques, this study aimed to determine what species of shark are involved in the Singapore shark fin trade.

Wallace's line structures seagrass microbiota and is a potential barrier to the dispersal of marine bacteria.

Background: The processes that shape microbial biogeography are not well understood, and concepts that apply to macroorganisms, like dispersal barriers, may not affect microorganisms in the same predictable ways. To better understand how known macro-scale biogeographic processes can be applied at micro-scales, we examined seagrass associated microbiota on either side of Wallace's line to determine the influence of this cryptic dispersal boundary on the community structure of microorganisms. Communities were examined from twelve locations throughout Indonesia on either side of this theoretical line.

DNA barcoding continues to identify endangered species of shark sold as food in a globally significant shark fin trade hub.

Shark fins are a delicacy consumed throughout Southeast Asia. The life history characteristics of sharks and the challenges associated with regulating fisheries and the fin trade make sharks particularly susceptible to overfishing. Here, we used DNA barcoding techniques to investigate the composition of the shark fin trade in Singapore, a globally significant trade hub.

Analysis of Toxic Metals Found in Shark Fins Collected from a Global Trade Hub.

As human activities release increasingly more fossil fuel-derived emissions directly into the atmosphere, terrestrial, aquatic, or marine ecosystems, the biomagnification and bioaccumulation of toxic metals in seafood is an ever more pressing concern. As apex predators, sharks are particularly susceptible to biomagnification and bioaccumulation. The consumption of shark fin is frequent throughout Asia, and their ingestion represents a pathway through which human exposure to potentially unsafe levels of toxic metals can occur.

Influence of native and exotic plant diet on the gut microbiome of the Gray's Malayan stick insect, .

Herbivorous insects require an active lignocellulolytic microbiome to process their diet. Stick insects (phasmids) are common in the tropics and display a cosmopolitan host plant feeding preference. The microbiomes of social insects are vertically transmitted to offspring, while for solitary species, such as phasmids, it has been assumed that microbiomes are acquired from their diet.

The core mangrove microbiome reveals shared taxa potentially involved in nutrient cycling and promoting host survival.

Background: Microbes have fundamental roles underpinning the functioning of our planet, they are involved in global carbon and nutrient cycling, and support the existence of multicellular life. The mangrove ecosystem is nutrient limited and if not for microbial cycling of nutrients, life in this harsh environment would likely not exist. The mangroves of Southeast Asia are the oldest and most biodiverse on the planet, and serve vital roles helping to prevent shoreline erosion, act as nursery grounds for many marine species and sequester carbon.

Bacterial and Fungal Co-Occurrence in the Nudibranch, .

Despite the increasing recognition and importance surrounding bacterial and fungal interactions, and their critical contributions to ecosystem functioning and host fitness, studies examining their co-occurrence remain in their infancy. Similarly, studies have yet to characterise the bacterial and fungal communities associated with nudibranchs or their core microbial members. Doing this can advance our understanding of how the microbiome helps a host adapt and persist in its environment.

Erratum: Author Correction: The influence of HLA genotype on the development of metal hypersensitivity following joint replacement.

[This corrects the article DOI: 10.1038/s43856-022-00137-0.].

The influence of HLA genotype on the development of metal hypersensitivity following joint replacement.

Background: Over five million joint replacements are performed across the world each year. Cobalt chrome (CoCr) components are used in most of these procedures. Some patients develop delayed-type hypersensitivity (DTH) responses to CoCr implants, resulting in tissue damage and revision surgery.

What Is in Your Shark Fin Soup? Probably an Endangered Shark Species and a Bit of Mercury.

Shark fin soup, consumed by Asian communities throughout the world, is one of the principal drivers of the demand of shark fins. This near USD 1 billion global industry has contributed to a shark population declines of up to 70%. In an effort to arrest these declines, the trade in several species of sharks is regulated under the auspices of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Diversity and Distribution of Microbial Communities Associated with Reef Corals of the Malay Peninsula.

Coral-associated bacteria play critical roles in the regulation of coral health and function. Environmental perturbations that alter the bacterial community structure can render the coral holobiont more susceptible and less resilient to disease. Understanding the natural variation of the coral microbiome across space and host species provides a baseline that can be used to distinguish shifts in community structure.

Barriers and corridors of gene flow in an urbanized tropical reef system.

Information about the distribution of alleles among marine populations is critical for determining patterns of genetic connectivity that are essential in modern conservation planning. To estimate population connectivity in Singapore's urbanized equatorial reef system, we analysed single nucleotide polymorphisms (SNPs) from two species of reef-building corals with distinct life histories. For sp.

Seeing through sedimented waters: environmental DNA reduces the phantom diversity of sharks and rays in turbid marine habitats.

Background: Sharks and rays are some of the most threatened marine taxa due to the high levels of bycatch and significant demand for meat and fin-related products in many Asian communities. At least 25% of shark and ray species are considered to be threatened with extinction. In particular, the density of reef sharks in the Pacific has declined to 3-10% of pre-human levels.

Biogeographic structure of fungal communities in seagrass Halophilia ovalis across the Malay Peninsula.

Distributed across both the tropical Atlantic and Pacific oceans, the seagrass Halophilia ovalis stabilizes coastal sediment, thereby preventing shoreline erosion and is also an important food source for megaherbivores such as dugongs. However, seagrass meadows globally are under severe duress due to both climate change and anthropogenic activities. We characterized the mycobiome of Halophilia ovalis at seven sites in the Malay Peninsula using ITS1 rDNA amplicon sequences and investigated differences in fungal community structure.

The Microbiome of the Reef Macroalga in Singapore.

The large canopy-forming macroalga, , provides shelter and food for numerous coral reef species, but it can also be detrimental at high abundances where it outcompetes other benthic organisms for light and space. Here, we investigate the microbial communities associated with in Singapore, where it is an abundant and important member of coral reef communities. We collected eight complete thalli from eight island locations along an approximate 14 km east-to-west transect.

Distinct fungal communities associated with different organs of the mangrove in the Malay Peninsula.

Mangrove forests are key tropical marine ecosystems that are rich in fungi, but our understanding of fungal communities associated with mangrove trees and their various organs remains limited because much of the diversity lies within the microbiome. In this study, we investigated the fungal communities associated with the mangrove tree throughout Peninsular Malaysia and Singapore. At each sampling location, we collected leaves, fruits, pneumatophores and sediment samples and performed amplicon sequencing of the ribosomal internal transcribed spacer 1 to characterise the associated communities.

Electrocardiographic QT Intervals in Infants Exposed to Hydroxychloroquine Throughout Gestation.

Background: Based on inhibition of viral replication and limited reports on clinical efficacy, hydroxychloroquine is being considered as prophylaxis and treatment of coronavirus disease-19 (COVID-19). Although hydroxychloroquine is generally considered safe during pregnancy based on studies in patients with systemic lupus erythematosus and other rheumatic conditions, there may still be reluctance to institute this antimalarial during pregnancy for the sole purpose of antiviral therapy.

Methods: To provide data regarding any potential fetal/neonatal cardiotoxicity, we leveraged a unique opportunity in which neonatal ECGs and hydroxychloroquine blood levels were available in a recently completed study evaluating the efficacy of hydroxychloroquine 400 mg daily to prevent the recurrence of congenital heart block associated with anti-SSA/Ro (anti-Sjögren's Syndrome A/Ro) antibodies.

Homogenization of Endosymbiont Communities Hosted by Equatorial Corals during the 2016 Mass Bleaching Event.

Thermal stress drives the bleaching of reef corals, during which the endosymbiotic relationship between Symbiodiniaceae microalgae and the host breaks down. The endosymbiont communities are known to shift in response to environmental disturbances, but how they respond within and between colonies during and following bleaching events remains unclear. In 2016, a major global-scale bleaching event hit countless tropical reefs.

Host age is not a consistent predictor of microbial diversity in the coral Porites lutea.

Corals harbour diverse microbial communities that can change in composition as the host grows in age and size. Larger and older colonies have been shown to host a higher diversity of microbial taxa and this has been suggested to be a consequence of their more numerous, complex and varied micro-niches available. However, the effects of host age on community structure and diversity of microbial associates remain equivocal in the few studies performed to date.

Hydroxychloroquine to Prevent Recurrent Congenital Heart Block in Fetuses of Anti-SSA/Ro-Positive Mothers.

Background: Experimental and clinical evidence support the role of macrophage Toll-like receptor signaling in maternal anti-SSA/Ro-mediated congenital heart block (CHB).

Objectives: Hydroxychloroquine (HCQ), an orally administered Toll-like receptor antagonist widely used in lupus including during pregnancy, was evaluated for efficacy in reducing the historical 18% recurrence rate of CHB.

Methods: This multicenter, open-label, single-arm, 2-stage clinical trial was designed using Simon's optimal approach.

Air mass source determines airborne microbial diversity at the ocean-atmosphere interface of the Great Barrier Reef marine ecosystem.

The atmosphere is the least understood biome on Earth despite its critical role as a microbial transport medium. The influence of surface cover on composition of airborne microbial communities above marine systems is unclear. Here we report evidence for a dynamic microbial presence at the ocean-atmosphere interface of a major marine ecosystem, the Great Barrier Reef, and identify that recent air mass trajectory over an oceanic or continental surface associated with observed shifts in airborne bacterial and fungal diversity.

Mangrove-Associated Fungal Communities Are Differentiated by Geographic Location and Host Structure.

Marine fungi on the whole remain understudied, especially in the highly diverse Southeast Asian region. We investigated the fungal communities associated with the mangrove tree throughout Singapore and Peninsular Malaysia. At each sampling location, we examined ten individual trees, collecting leaves, fruits, pneumatophores, and an adjacent sediment sample from each plant.

Autoimmune-mediated congenital heart block.

Autoimmune-mediated congenital heart block (CHB) is a severe manifestation of neonatal lupus in which conduction tissues of the fetal heart are damaged. This occurs due to passive transference of maternal anti-SSA/Ro and anti-SSB/La autoantibodies and subsequent inflammation and fibrosis of the atrioventricular (AV) node. Notably, the disease manifests after the fetal heart has structurally developed, ruling out other anatomical abnormalities that could otherwise contribute to the block of conduction.