Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and affects Penaeus monodon and ...Litopenaeus vannamei shrimp cultures. The bacterium contains the pirA‐ and pirB‐like genes in 69‐ to 70‐Kb plasmids, which encode the toxins that produce the disease. The aim of this study was to determine whether pirA‐ and pirB‐like genes existed in bacterial genera distinct from Vibrio before the first cases of AHPND were documented in Mexico. Two bacterial isolates were selected from shrimp farms in Nayarit in 2006 and analysed by nested‐PCR to determine the presence of pirA‐ and pirB‐like genes. The two isolates chosen did indeed show the presence of these genes, and those findings were confirmed by sequencing. Both strains matched to the bacterial species Micrococcus luteus. Results revealed two important situations: (a) the pirA‐ and pirB‐like genes were present in a bacterial species that has not been reported previously (Micrococcus luteus); and (b) pirA‐ and pirB‐like bacterial genes were present in Mexico before the first AHPND outbreak was reported in China.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The failure of relapses and white matter lesions to properly explain long-term disability and progression in multiple sclerosis is compounded by its artificial separation into relapsing remitting, ...secondary progressive, and primary progressive pigeonholes. The well-known epidemiological disconnection between relapses and long-term disability progression has been rediscovered as “progression independent of relapse activity”, i.e. smouldering multiple sclerosis. This smouldering associated worsening proceeds despite early and prolonged use of disease modification therapies, even those that are highly effective at preventing relapses and new/enhancing white matter lesions on MRI. We recognise that smouldering associated worsening and relapse/lesion associated worsening coexist, to varying extents.
The extent of cortical demyelination has been shown to correlate significantly with the severity of diffuse injury in normal appearing white matter (post mortem histopathologically (r = 0.55; P = 0.001), and in vivo with MRI (r = -0.6874; P = 0.0006)) and does so independently of white matter lesion burden. Axon loss in the normal appearing white matter explains disability in multiple sclerosis better than focal white matter lesions do. Smouldering associated worsening typically manifests as a length-dependent central axonopathy.
We propose a unifying model for multiple sclerosis pathogenesis, wherein accumulation of cortical lesion burden predisposes associated normal appearing white matter to diffuse injury, whilst also intensifying damage within white matter lesions. Our novel two-hit hypothesis implicates cortical disease as a culprit for smouldering multiple sclerosis, abetted by active focal inflammation in the white matter (and vice versa). Substantiation of the two-hit hypothesis would advance the importance of specific therapeutic intervention for (and monitoring of) cortical/meningeal inflammation in people with multiple sclerosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND), results in significant mortality in penaeid shrimp aquaculture. AHPND is caused by toxins secreted by pathogenic ...strains of Vibrio parahaemolyticus, that have acquired a unique 63–70 kb AHPND-associated plasmid (pVA1). This plasmid encodes the binary PirA/BVP toxins that consist of two subunits PirAVP and PirBVP. Consequently, the degradation of these toxins might be a valid strategy to control or mitigate AHPND. There is literature-based evidence that the application of Bacillus improves shrimp survival upon challenge with pathogenic V. parahaemolyticus. In this study, Bacillus subtilis DSM33018 strain was shown to degrade AHPND toxins in vitro, as detected by Western blots. Further, an in vivo challenge test, using gnotobiotically cultured brine shrimp Artemia franciscana exposed to PirA/BVP toxins, the DSM33018 Bacillus strain could completely alleviate toxicity. This finding indicates that mitigation of AHPND might include Bacillus-based degradation of PirVP toxins.
•This is the first scientific evidence on AHPND toxin degradation by Bacillus strains.•PirBVP is more susceptible to degradation by Bacillus strains than PirAVP.•PirA/BVP-induced mortality in Artemia can be mitigated by certain Bacillus strains
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Acute hepatopancreatic necrosis disease (AHPND) is a bacterial disease associated to severe mortality in farmed shrimps, and caused by Vibrio parahaemolyticus containing plasmid pVA-1 encoding pirA ...and pirB toxins. This study investigates the presence of Vibrio spp. carrying plasmid pVA-1 in post larvae and juveniles Penaeus vannamei from farms located in Costa Rica. Moreover, a possible corelation between Vibrio spp. presence, management parameters, and water quality was also investigated. Between 2017 and 2018, post larvae, the first water pumped into ponds, and juvenile shrimp (6 to 7 weeks after stocking) were collected from 15 farms located in the Gulf of Nicoya and the country's Central Pacific region. On the day when the juvenile shrimp were collected, a survey was applied to farmers to obtain information about management conditions, finally physical-chemical parameters of pond water were measured. Plasmidic pVA-1 pirA and pirB genes were detected in hepatopancreas of juvenile shrimp in 5 (33.3%) farms, while Vibrio spp. were found in 6 (40.0%) farms. Sequencing of pVA-1, pirA and pirB genes showed 99–100% similarity to pathogenic Vibrio parahemolyticus XN89 homologous genes identified in Vietnamese shrimps. Statistically significant differences were found in the water volume (p < .03), rate of water replacement (p < .04), and farms disease history (p < .05). A correlation between presence of Vibrio spp. and water quality was not established. The molecular diagnosis of Vibrio spp., the plasmid and the genes encoding toxins that are associated with AHPND are reported for the first time in Costa Rica. Further studies aimed to isolate AHPND-causing Vibrio spp. from ponds, to generate histopathological data, and to establish economic losses due to AHPND mortalities in Penaeus vannamei farms, are needed to clarify the role and pathogenic features of Vibrio spp. in AHPND.
•Molecular detection of Vibrio spp. is reported for the first time in 40.0% of shrimp farms•Plasmidic pVA-1 and pirA/pirB genes associated to AHPND were detected in 33% of farms•pVA-1 was found in hepatopancreas of juvenile shrimp•Correlation between presence of Vibrio spp. and water quality was not established.•Statistically significant differences were found in the water volume, rate of water replacement, and farms disease history.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A major therapeutic goal in the treatment of multiple sclerosis (MS) is to prevent the accumulation of disability over an often decades-long disease course. Disability progression can result from ...acute relapses as well as from CNS intrinsic parenchymal disintegration without de novo CNS lesion formation. Research focus has shifted to progression not associated with acute inflammation, as it is not sufficiently controlled by currently available treatments. This review outlines how recent advances in the understanding of the pathogenesis of progressive MS have been facilitated by the development of more precise, less static pathogenetic concepts of progressive MS, as well as by new techniques for the analysis of region-specific proteomic and transcriptomic signatures in the human CNS. We highlight key drivers of MS disease progression and potential targets in its treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study aimed to detect the presence of quorum-sensing (QS) signalling molecules and evaluate the in vivo virulence gene expression in shrimp challenged with acute hepatopancreatic necrosis ...disease (AHPND) positive Vibrio isolates. Three types of QS signal molecules, namely N-acyl-homoserine lactone (AHL), Autoinducer-2 (AI-2) and Cholerae autoinducer-1-like (CAI-1) molecules were detected in AHPND causing isolates using Agrobacterium tumefaciens KYC55, Vibrio campbellii JMH597 and V. campbellii JAF375 biosensors respectively. The presence of QS genes in all the 12 AHPND positive isolates was further justified by conducting molecular screening of the QS-related genes, luxR and luxS. Challenged groups demonstrated a significant (P < 0.05) increase in the expression levels of the QS master regulator gene luxR compared with the unchallenged group. The expression of pirA-, pirB-, toxR- and luxR genes peaked at 36 h in shrimp challenged with AHPND positive Vibrio parahaemolyticus BpShHep31 and V. harveyi BpShHep24. However, compared to the group challenged with V. parahaemolyticus BpShHep31, the V. harveyi BpShHep24 challenged group demonstrated 45.1-, 126.0-, 19.7- and 10.7- fold higher expression of pirA, pirB, toxR and luxR respectively.
•The autoinducer-1 (AI-1) and autoinducer-2 (AI-2) are the major quorum sensing signals produced by the AHPND isolates.•Expression level of pirA-, pirB-, luxR- and toxR- regulated virulence genes increased proportionally with high mortality rates in the shrimp challenged with AHPND positive isolates.•Up-regulation of the production capacity of pirA, pirB, toxR and luxR were observed at 36 h.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Shrimp has become a highly traded global seafood product, with 8 million tons of shrimp produced annually. Acute hepatopancreatic necrosis disease (AHPND) is the most prevalent and severe disease ...affecting shrimp aquaculture, resulting in considerable economic losses. The AHPND incidence in shrimp farming was as high as 60%–80% in China, resulting in reduced farming capacity and unstable production. Vibrio parahaemolyticus has been identified as the main causative agent of AHPND. In addition, V. harveyi, V. cambelii, V. algolyticus, and V. owenii are capable of causing similar diseases, demonstrating a distinct pathogenic diversity. Previous studies have indicated that not all of the above-mentioned Vibrios species are capable of causing AHPND, and whole gene sequencing and knockout genes have revealed that pirA and pirB are the primary pathogenic factors responsible for AHPND in shrimp. Specifically, the causative agent for AHPND should be a specific strain of Vibrio carrying the binary toxins pirAVp and pirBVp on the extrachromosomal virulence plasmid pVA1. Among them, the pirB toxin mainly determines the pathogenicity of the bacterium, whereas the pirA virulence is relatively weak. Furthermore, it has been demonstrated that the virulence plasmids encoding the binary genes pirAVp and pirBVp are the main causative agents of AHPND. The virulence gene toxR is prevalent in Vibrio and plays an important role through the genetic diversity of 16S rRNA genes during shrimp infection. Real-time fluorescence quantitative PCR technology has less contamination, more accurate quantification, real-time monitoring, and greater automation than conventional PCR technology, which has been utilized in the fields of transgenic detection, environmental science, and medicine. However, this technique is time-consuming, involves multiple instruments and reagents, and requires personnel with extensive professional skills and experience. As a result of its small size, low sample and reagent consumption, rapid detection speed, miniaturization, and integration, microfluidic chip assay technology has emerged as a new focal point in assay technology. Therefore, in this study, we designed specific primers and established a microfluorescence quantitative PCR assay based on two genes, pirA and pirB, to address the genetic similarity of AHPND pathogens carrying a large plasmid encoding a binary toxin, pirA and pirB. The method was specific for the pathogenic pirA and pirB genes, and only when DNA from AHPND-infected samples was tested could the two genes be successfully amplified, while all other pathogenic bacteria were detected with negative results. The sensitivity was high, and the minimum detection limits for the pirA and pirB genes were 5.43×100 and 4.31×101 copies/μL, respectively. Standard curves for pirA and pirB were constructed and demonstrated good linearity in the concentration range of 5.43×109–5.43×104 copies/μL for pirA (y= –3.145x+6.63, R2=0.999) and 4.31×109–4.31×104 copies/μL for pirB (y= –3.015x+5.45, R2=0.999), with an average sample detection time of approximately 26 min. In order to evaluate the efficacy of the method in practice, artificial infection experiments with V. parahaemolyticus were performed. In this study, artificial infection experiments were induced by both injection and immersion, and samples were collected at different time periods to clinically validate the established method and compare its effectiveness in detecting different shrimp tissues, thereby facilitating a more thorough analysis of the pathogenic pathways of infection. The experimental group with injection as the mode of infection was found to be positive for all tissues in all time periods except the water test, which was negative. The experimental group that used immersion as the infection method showed different results for various time periods and with different genetic tests. In terms of the infection method, the tissues could be infiltrated within 2 h using the injection method, whereas the target genes were not detected in the hepatopancreas at 6 h using the immersion method. This indicated that the injection method infiltrated the tissues more rapidly than the immersion method. According to the comparison results of the three genes, pirB was only negative in the intestine at 2 h and positive in all tissues the rest of the time; pirA was negative in the hepatopancreas and intestine at 2 h, only the intestine was negative at 6 h, and all tissues were positive at 12 h; and toxR was negative in all tissues at 2 h. The rate of infestation from rapid to slow showed that pirB > pirA > toxR. Based on the rate of tissue infestation, pirA and pirB were detected in both cheek filaments and muscles at 2 h, making them the most rapid infiltration agents. Therefore, the strategy of using pirB as the primer and gill filament or muscle as the target tissue is more suitable for the rapid detection of AHPND in the field. In this study, we established a method for microfluidic fluorescent quantitative PCR that has the advantages of being rapid, sensitive, high throughput, less contaminated, on-site detectable, and integrated. The method is not only applicable to the laboratory but also meets the requirements of rapid field detection at hatcheries and farms, and can be used as a new technical method for shrimp fry quality detection and disease control.
This essay emphasizes the founding values of Mediterranean Europe understood as a demo- cratic community of persons. In particular, the Author moves from Jacques Maritain’s thought and from the idea ...of European federalism in order to point it out that Europe, thanks to the ‘human bridges’ of Giorgio La Pira, can be not only an economic union, but also and above all a human community founded upon the respect and dignity of the person. From these values derive true democracy and protection of human rights which represent the essential core of Mediterranean Europe.
This article addresses the scholarly debate over sectarianism and the Provisional Irish Republican Army's (PIRA) campaign during the Northern Ireland Troubles. It argues that although there is much ...merit in the contributions made in this discourse, unfortunately, for, the most part, there is a lack of engagement with the deeper meaning of sectarianism. Consequently, it seeks to enhance the understanding of sectarianism within this arena before considering the nature of the PIRA campaign. By conducting a thorough analysis of the killings conducted by this organisation in the early years of the conflict it is ultimately concluded that, at the very least, PIRA tolerated, and likely sanctioned, sectarian violence from within its ranks.
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BFBNIB, NUK, PILJ, SAZU, UL, UM, UPUK
I processi di trasformazione che hanno interessato il campo fumettistico al crocevia del secolo si allacciano strettamente alla digitalizzazione e all’integrazione del sistema mediale. Accanto ...all’affermazione del graphic novel, che permette al fumetto di convergere verso archi narrativi organici di matrice romanzesca, si delineano tendenze al riscatto dei generi brevi del fumetto classico: la striscia umoristica, la vignetta fulminante, la tavola autoconclusiva. L’accrescimento vertiginoso dei flussi sviluppati dal web favorisce la trasposizione, il ricircolo, la stratificazione di simili schegge fumettistiche, tra comunicazione analogica e comunicazione digitale. Si tratta di proposte che insorgono dal basso, da protagonisti della compartecipazione creativa socialmediale o da rinnovatori della cultura underground. L’intreccio fra interazione estetica istituzionale e medialità autogestita, pur vincolato all’oligopolio delle piattaforme, dischiude originali opportunità di differenziazione e arricchimento dell’esperienza fumettistica.
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