Mislabeling of seafood is a global phenomenon that can misrepresent the status and level of consumption of wild fish stocks while concealing the use of many other wild species or those originating ...from aquaculture and sold as substitutes. We conducted a DNA barcoding study in three cities within Mexico (Mazatlan, Mexico City and Cancun) and sequenced the COI gene in 376 fish samples sold as 48 distinct commercial names at fish markets, grocery stores, and restaurants. Our goal was to identify the main species sold, their mislabeling rates and the species most used as substitutes. Overall, the study-wide mislabeling rate was 30.8% (95% CI 26.4-35.6). Half of the samples collected belonged to five species traded globally (yellowfin tuna, Atlantic salmon, mahi, swai, and tilapia), most of them with important aquaculture or ranching production levels. These species were commonly used as substitutes for other species and showed low mislabeling rates themselves (≤ 11%, except mahi mahi with 39% mislabeling). The other half of the samples revealed nearly 100 species targeted by small-scale fishers in Mexico and sold under 42 distinct commercial names. Popular local commercial names (dorado, marlin, mero, robalo, mojarra, huachinango, pargo, sierra) showed the highest mislabeling rates (36.3% to 94.4%) and served to sell many of the 53 species identified as substitutes in our study. We discuss the observed patterns in relation to landing and import data showing differences in availability of commercial species and the links to explain observed mislabeling rates and the use of a species as a substitute for other species. We also outline some of the implications of establishing a labeling and traceability standard as an alternative to improve transparency in the trade of seafood products in Mexico.
Seafood mislabeling has the potential to mask changes in the supply of species due to overfishing, while also preventing consumers from making informed choices about the origin, quality and ...sustainability of their food. Thus, there is a need to understand mislabeling and analyze the potential causes behind it to propose solutions. We conducted a COI DNA barcoding study in La Paz, Baja California Sur, Mexico, with 74 samples from fish markets and 50 samples from restaurants. We identified 38 species sold under 19 commercial names, from which at least ∼80% came from local small-scale fisheries. Overall, 49 samples, representing 40% (95% CI 31.4-48.3) were considered mislabeled in our samples. Based on analyses where species were assigned to three price categories, economic incentives were associated with approximately half of the mislabeling events observed, suggesting that other motivating factors might simultaneously be at play. Using a network approach to describe both mislabeling (when species are mislabeled as the focal species) and substitution (when the focal species is used as substitute for others), we calculated proxies for the net availability of each species in the market. We found that local fish landings were a significant predictor of the net availability of the 10 most important commercial species at retail, but this true availability was masked to the eyes of the final consumer by both mislabeling and substitution. We hypothesize that the level of supply of each species could help explain mislabeling and substitution rates, where species in low supply and high demand could show higher mislabeling rates and rarely be used as substitutes, while species in high supply and low demand could be used as substitutes for the preferred species. Other factors affecting mislabeling include national regulations that restrict the fishing or commercialization of certain species and local and global campaigns that discourage specific patterns of consumption. We discuss how these factors might influence mislabeling and propose some solutions related to communication and education efforts to this local and global challenge.
We characterized a set of new hypervariable microsatellite loci for the barred sand-bass (
Paralabrax nebulifer
), a marine fish that supports important recreational and artisanal fisheries in ...California, USA and the west coast of the Baja California Peninsula, Mexico. We performed a shotgun genome sequencing with the 454 XL titanium chemistry and used bioinformatics to search for microsatellite loci with perfect repeats. We selected 40 primer pairs that were synthesized and genotyped in an ABI PRISM 3730XL DNA sequencer in 32 individuals from San Juanico, Baja California Sur. We estimated levels of genetic diversity, deviations from linkage and Hardy–Weinberg equilibrium, the frequency of null alleles and the probability of individual identity for the new markers. We successfully scored 24 microsatellite loci (13 tetranucleotides and 11 dinucleotides). The average number of alleles per locus was 12.5 (range 4–23). The average observed and expected heterozygosities were 0.779 (range 0.313–0.969) and 0.774 (range 0.350–0.939), respectively. We detected significant linkage disequilibrium in two pairs of loci. Genotype frequencies at seven loci showed significant deviations from the expectations of Hardy–Weinberg equilibrium and had estimated null allele frequencies ≥10%. The probability of individual identity for the new loci was 8.5
−36
. The new markers will be useful for investigating patterns of fine-scale genetic structure and diversity to estimate larval dispersal and assess metapopulation dynamics, information necessary for the sustainable management of
P. nebulifer
fisheries at the west coast of the Baja California Peninsula.
The fishery for octopus in Northwest Mexico has increased to over 2,000 tons annually, but to date the specific composition of the catch has been ignored. With at least three main species targeted by ...artisanal fisheries in the region with distinct life histories, the lack of basic biological information about the distribution, metapopulation size and structure of each species could impede effective fisheries management to avoid overexploitation. We tested if different life histories of three species of octopus could help predict observed patterns of genetic diversity, population dynamics, structure and connectivity and how this information could be relevant to the sustainable management of the fishery. We sequenced two mitochondrial genes and genotyped seven nuclear microsatellite loci to identify the distribution of each species in 20 locations from the Gulf of California and the west coast of the Baja California peninsula. We tested five hypotheses derived from population genetic theory based on differences in the fecundity and dispersal potential for each species. We discovered that
with low fecundity and direct development (without a planktonic phase) had lower average effective population size and genetic diversity, but higher levels of kinship, population structure, and richness of private alleles, than the other two species. These features indicated limited dispersal and high local recruitment. In contrast,
and
with higher fecundity and planktonic phase as paralarvae had higher effective population size and genetic diversity, and overall lower kinship and population structure than
. These observations supported higher levels of gene flow over a larger geographical scale.
with the longest planktonic paralarval duration and therefore larger dispersal potential had differences in the calculated parameters possibly associated with increased connectivity. We propose
is more susceptible to over exploitation of small, isolated populations and could have longer recovery times than the other two species. This species may benefit from distinct fishery management within each local population.
and
may benefit from fishery management that takes into account metapopulation structure over larger geographic scales and the directionality and magnitude of larval dispersal driven by ocean currents and population connectivity among individuals of each locality. The distribution of each species and variations in their reproductive phenology is also important to consider when establishing marine reserves or seasonal fishing closures.
Mislabeling of seafood is a global phenomenon that can misrepresent the status and level of consumption of wild fish stocks while concealing the use of many other wild species or those originating ...from aquaculture and sold as substitutes. We conducted a DNA barcoding study in three cities within Mexico (Mazatlan, Mexico City and Cancun) and sequenced the COI gene in 376 fish samples sold as 48 distinct commercial names at fish markets, grocery stores, and restaurants. Our goal was to identify the main species sold, their mislabeling rates and the species most used as substitutes. Overall, the study-wide mislabeling rate was 30.8% (95% CI 26.4–35.6). Half of the samples collected belonged to five species traded globally (yellowfin tuna, Atlantic salmon, mahi, swai, and tilapia), most of them with important aquaculture or ranching production levels. These species were commonly used as substitutes for other species and showed low mislabeling rates themselves (≤ 11%, except mahi mahi with 39% mislabeling). The other half of the samples revealed nearly 100 species targeted by small-scale fishers in Mexico and sold under 42 distinct commercial names. Popular local commercial names (dorado, marlin, mero, robalo, mojarra, huachinango, pargo, sierra) showed the highest mislabeling rates (36.3% to 94.4%) and served to sell many of the 53 species identified as substitutes in our study. We discuss the observed patterns in relation to landing and import data showing differences in availability of commercial species and the links to explain observed mislabeling rates and the use of a species as a substitute for other species. We also outline some of the implications of establishing a labeling and traceability standard as an alternative to improve transparency in the trade of seafood products in Mexico.
The microbiome of uncontacted Amerindians Clemente, Jose C; Pehrsson, Erica C; Blaser, Martin J ...
Science advances,
2015-Apr-03, Letnik:
1, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Most studies of the human microbiome have focused on westernized people with life-style practices that decrease microbial survival and transmission, or on traditional societies that are currently in ...transition to westernization. We characterize the fecal, oral, and skin bacterial microbiome and resistome of members of an isolated Yanomami Amerindian village with no documented previous contact with Western people. These Yanomami harbor a microbiome with the highest diversity of bacteria and genetic functions ever reported in a human group. Despite their isolation, presumably for >11,000 years since their ancestors arrived in South America, and no known exposure to antibiotics, they harbor bacteria that carry functional antibiotic resistance (AR) genes, including those that confer resistance to synthetic antibiotics and are syntenic with mobilization elements. These results suggest that westernization significantly affects human microbiome diversity and that functional AR genes appear to be a feature of the human microbiome even in the absence of exposure to commercial antibiotics. AR genes are likely poised for mobilization and enrichment upon exposure to pharmacological levels of antibiotics. Our findings emphasize the need for extensive characterization of the function of the microbiome and resistome in remote nonwesternized populations before globalization of modern practices affects potentially beneficial bacteria harbored in the human body.
Sediment supply in rivers is the dominant material source for ecosystems, which have been undergoing large variations globally. The objective of this research was to study the spatial distribution of ...runoff and sediment load in river Quito (Choco, Colombia), which is affected by extreme gold mining practices. Long-term daily mean discharge data from gauging stations were analyzed. The runoff values of 297, 210 and 141 m3/s have exceeded (in %) 50, 70 and 90 during 2001–2011 in the river Quito. In river Atrato 976, 706 and 500 m3/s have occurred (in %) 50, 75 and 90 during 1984–2015. Suspended sediment concentrations were measured using a linear equation derived from the results obtained from laboratory analysis of field samples and acoustic doppler current profiler. Minimum and maximum flow discharge (Q) observed using ADCP instrument was 0.59 m3/s at the tributary and 370 m3/s at the downstream of main river indicating that the tributaries play an important role in sediment supply. Spatially distinct trends in suspended sediment load, with an increasing trend from the upstream (73.73 tons/day) to downstream (3140.82 tons/day) in the main channel is observed. Significant correlation (r2 = 0.79 and 0.85 for tributary and main river, respectively) between the SSL and Q suggests that the SSL depends on the intensity of runoff, governed by the extreme rainfall condition. In contrast, no significant correlation was observed between Q and SSC due to the continuous migration of mining dredges and dumping of mine tailing piles at the riverbank. The results provide support for river management to engineers, where the best conservation/management practices that can be implemented.
Display omitted
•SSC of River Quito was established using ADCP instrument and laboratory analysis of field samples.•Extreme rainfall, tributaries and localized human activities modify river flow and sediment transport regimes.•Spatially distinct trends in SSC with both increasing and decreasing trends were observed due to anthropogenic activities.•Average suspended sediment load in the Quito River basin was 668.08 tons/day.
In response to inflammatory stimuli, monocytes/macrophages secrete greater quantities of the proinflammatory cytokines tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6. The ...inflammatory process and the innate immune response are related to the activation of several transcription factors, such as nuclear factor κB (NF-κB) and activator protein 1 (AP-1). The proteasome is a multimeric protease complex, which plays a vital role in several cellular functions, including the regulation of transcription factors like NF-κB. In this study, we used the human monocyte cell line U937 stimulated with lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) as a model to investigate the in vitro effects of MG132, a proteasome inhibitor, on the release of TNF-α, IL-1β and IL-6 and on the expression of their membrane and soluble receptors TNF-R1, IL-1R1 and IL-6R. We also analysed the effects of MG132 on the activation of NF-κB and AP-1 and on the IκB molecule. MG132 significantly inhibited the secretion of those proinflammatory cytokines. MG132 increased the release of the soluble receptors TNF-R1 and IL-1R1 from U937 cells and decreased their cell-surface expression. MG132 also increased IL-6R cell-surface expression and decreased its release. Proteasome inhibition also led to an increase in LPS+PMA-induced AP-1 activation and the attenuation of LPS+PMA-induced IκB degradation, resulting in the abolition of NF-κB activation. Our experiments strongly suggest that the proteasome is an important factor in the regulation of proinflammatory cytokines and their receptors.
Background and Objectives
The efficacy of COVID‐19 convalescent plasma (CP) associates with high titres of antibodies. ConPlas‐19 clinical trial showed that CP reduces the risk of progression to ...severe COVID‐19 at 28 days. Here, we aim to study ConPlas‐19 donors and characteristics that associate with high anti‐SARS‐CoV‐2 antibody levels.
Materials and Methods
Four‐hundred donors were enrolled in ConPlas‐19. The presence and titres of anti‐SARS‐CoV‐2 antibodies were evaluated by EUROIMMUN anti‐SARS‐CoV‐2 S1 IgG ELISA.
Results
A majority of 80.3% of ConPlas‐19 donor candidates had positive EUROIMMUN test results (ratio ≥1.1), and of these, 51.4% had high antibody titres (ratio ≥3.5). Antibody levels decline over time, but nevertheless, out of 37 donors tested for an intended second CP donation, over 90% were still EUROIMMUN positive, and nearly 75% of those with high titres maintained high titres in the second sample. Donors with a greater probability of developing high titres of anti‐SARS‐CoV‐2 antibodies include those older than 40 years of age (RR 2.06; 95% CI 1.24–3.42), with more than 7 days of COVID‐19 symptoms (RR 1.89; 95% CI 1.05–3.43) and collected within 4 months from infection (RR 2.61; 95% CI 1.16–5.90). Male donors had a trend towards higher titres compared with women (RR 1.67; 95% CI 0.91–3.06).
Conclusion
SARS‐CoV‐2 CP candidate donors' age, duration of COVID‐19 symptoms and time from infection to donation associate with the collection of CP with high antibody levels. Beyond COVID‐19, these data are relevant to inform decisions to optimize the CP donor selection process in potential future outbreaks.
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