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Youjun Feng - One of the best experts on this subject based on the ideXlab platform.
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Functional Definition of NrtR, a remnant regulator of NAD+ homeostasis in the zoonotic pathogen Streptococcus suis
FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 2019Co-Authors: Qingjing Wang, Bachar H. Hassan, Ningjie Lou, Justin Merritt, Youjun FengAbstract:NAD+ is an enzyme cofactor required for the 3 domains of life. However, little is known about the NAD+ biosynthesis and salvage pathways in the opportunistic pathogen Streptococcus suis. A genome-wide search allows us to identify the NAD+ salvage pathway encoded by an operon of nadR-pnuC-nrtR (from SSU05_1973 to SSU05_1971 on the reverse strand) in the S. suis 05ZYH33 that causes streptococcal toxin shock-like syndrome. The regulator of this pathway is Nudix-related transcriptional regulator (NrtR), a transcription regulator of the Nudix family comprising an N-terminal Nudix-like effector domain, and a C-terminal DNA-binding winged helix-turn-helix-like domain. Intriguingly, the S. suis NrtR naturally contains a single amino acid substitution (K92E) in the catalytic site of its Nudix domain that renders it catalytically inactive but does not influence its ability to bind DNA. Despite its lack of enzymatic activity, DNA-binding activity of NrtR is antagonized by the effector ADP-ribose. Furthermore, nrtR knockout in S. suis serotype 2 reduces its capacity to form biofilms and attenuates its virulence in a mouse infection model. Genome mining indicates that nrtR appears in a strain-specific manner whose occupancy is correlated to bacterial infectivity. Unlike the paradigmatic member of NrtR family having 2 unrelated functions (Nudix hydrolase and DNA binding), S. suis 2 retains a single regulatory role in the modulation of NAD+ salvage. This control of NAD+ homeostasis contributes to S. suis virulence.-Wang, Q., Hassan, B. H., Lou, N., Merritt, J., Feng, Y. Functional Definition of NrtR, a remnant regulator of NAD+ homeostasis in the zoonotic pathogen Streptococcus suis.
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Functional Definition of BirA suggests a biotin utilization pathway in the zoonotic pathogen Streptococcus suis
Scientific reports, 2016Co-Authors: Mingzhu Cai, Huimin Zhang, Ronghui Wen, Youjun FengAbstract:Biotin protein ligase is universal in three domains of life. The paradigm version of BPL is the Escherichia coli BirA that is also a repressor for the biotin biosynthesis pathway. Streptococcus suis, a leading bacterial agent for swine diseases, seems to be an increasingly-important opportunistic human pathogen. Unlike the scenario in E. coli, S. suis lacks the de novo biotin biosynthesis pathway. In contrast, it retains a bioY, a biotin transporter-encoding gene, indicating an alternative survival strategy for S. suis to scavenge biotin from its inhabiting niche. Here we report Functional Definition of S. suis birA homologue. The in vivo functions of the birA paralogue with only 23.6% identity to the counterpart of E. coli, was judged by its ability to complement the conditional lethal mutants of E. coli birA. The recombinant BirA protein of S. suis was overexpressed in E. coli, purified to homogeneity and verified with MS. Both cellulose TLC and MALDI-TOFF-MS assays demonstrated that the S. suis BirA protein catalyzed the biotinylation reaction of its acceptor biotin carboxyl carrier protein. EMSA assays confirmed binding of the bioY gene to the S. suis BirA. The data defined the first example of the biFunctional BirA ligase/repressor in Streptococcus.
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Functional Definition of luxs an autoinducer 2 ai 2 synthase and its role in full virulence of streptococcus suis serotype 2
Journal of Microbiology, 2011Co-Authors: Min Cao, Youjun Feng, Changjun Wang, Feng Zheng, Hui Liao, Yinghua Mao, Xiuzhen Pan, Jing Wang, Jiaqi TangAbstract:Quorum sensing is a widespread chemical communication in response to fluctuation of bacterial population density, and has been implicated into bacterial biofilm formation and regulation of expression of virulence factors. The luxS gene product, S-ribosylhomocysteinase, catalizes the last committed step in biosynthetic pathway of autoinducer 2 (AI-2), a signaling molecule for inter-species quorum sensing. We found a luxS homologue in 05ZYH33, an epidemic strain of Streptococcus suis serotype 2 (SS2) in China. A luxS null mutant (ΔluxS) of 05ZYH33 strain was obtained using an approach of homologous recombination. LuxS was determined to be required for AI-2 production in 05ZYH33 strain of S. suis 2. Inactivation of luxS gene led to a wide range of phenotypic changes including thinner capsular walls, increased tolerance to H2O2, reduced adherence capacity to epithelial cells, etc. In particular, loss of LuxS impaired dramatically its full virulence of SS2 in experimental model of piglets, and Functional complementation restored it nearly to the level of parent strain. Genome-wide transcriptome analyses suggested that some known virulence factors such as CPS are down-regulated in the ΔluxS mutant, which might in part explain virulence attenuation by luxS deletion. Similarly, 29 of 71 genes with different expression level were proposed to be targets candidate regulated by LuxS/AI-2-dependent quorum sensing.
Jeffrey G. Ojemann - One of the best experts on this subject based on the ideXlab platform.
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Functional Definition of seizure provides new insight into post traumatic epileptogenesis
Brain, 2009Co-Authors: Raimondo Dambrosio, Shahin Hakimian, Tessandra Stewart, Derek R. Verley, Jason S. Fender, Clifford L. Eastman, Aaron H. Sheerin, Puneet Gupta, Ramon Diazarrastia, Jeffrey G. OjemannAbstract:Experimental animals’ seizures are often defined arbitrarily based on duration, which may lead to misjudgement of the syndrome and failure to develop a cure. We employed a Functional Definition of seizures based on the clinical practice of observing epileptiform electrocorticography and simultaneous ictal behaviour, and examined post-traumatic epilepsy induced in rats by rostral parasagittal fluid percussion injury and epilepsy patients evaluated with invasive monitoring. We showed previously that rostral parasagittal fluid percussion injury induces different types of chronic recurrent spontaneous partial seizures that worsen in frequency and duration over the months post injury. However, a remarkable feature of rostral parasagittal fluid percussion injury is the occurrence, in the early months post injury, of brief (<2 s) focal, recurrent and spontaneous epileptiform electrocorticography events (EEEs) that are never observed in sham-injured animals and have electrographic appearance similar to the onset of obvious chronic recurrent spontaneous partial seizures. Simultaneous epidural-electrocorticography and scalp-electroencephalography recordings in the rat demonstrated that these short EEEs are undetectable by scalp electrocorticography. Behavioural analysis performed blinded to the electrocorticography revealed that (i) brief EEEs lasting 0.8–2 s occur simultaneously with behavioural arrest; and (ii) while behavioural arrest is part of the rat's behavioural repertoire, the probability of behavioural arrest is greatly elevated during EEEs. Moreover, spectral analysis showed that EEEs lasting 0.8–2 s occurring during periods of active behaviour with dominant theta activity are immediately followed by loss of such theta activity. We thus conclude that EEEs lasting 0.8–2 s are ictal in the rat. We demonstrate that the assessment of the time course of fluid percussion injury-induced epileptogenesis is dramatically biased by the Definition of seizure employed, with common duration-based arbitrary Definitions resulting in artificially prolonged latencies for epileptogenesis. Finally, we present four human examples of electrocorticography capturing short (<2 s), stereotyped, neocortically generated EEEs that occurred in the same ictal sites as obvious complex partial seizures, were electrographically similar to rat EEEs and were not noted during scalp electroencephalography. When occurring in the motor cortex, these short EEEs were accompanied by ictal behaviour detectable with simultaneous surface electromyography. These data demonstrate that short (<2 s) focal recurrent spontaneous EEEs are seizures in both rats and humans, that they are undetectable by scalp electroencephalography, and that they are typically associated with subtle and easily missed behavioural correlates. These findings define the earliest identifiable markers of progressive post-traumatic epilepsy in the rat, with implications for mechanistic and prophylactic studies, and should prompt a re-evaluation of the concept of post-traumatic silent period in both animals and humans.
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Functional Definition of seizure provides new insight into post-traumatic epileptogenesis
Brain, 2009Co-Authors: Raimondo D'ambrosio, Shahin Hakimian, Tessandra Stewart, Derek R. Verley, Jason S. Fender, Clifford L. Eastman, Aaron H. Sheerin, Puneet Gupta, Ramon Diaz-arrastia, Jeffrey G. OjemannAbstract:Experimental animals’ seizures are often defined arbitrarily based on duration, which may lead to misjudgement of the syndrome and failure to develop a cure. We employed a Functional Definition of seizures based on the clinical practice of observing epileptiform electrocorticography and simultaneous ictal behaviour, and examined post-traumatic epilepsy induced in rats by rostral parasagittal fluid percussion injury and epilepsy patients evaluated with invasive monitoring. We showed previously that rostral parasagittal fluid percussion injury induces different types of chronic recurrent spontaneous partial seizures that worsen in frequency and duration over the months post injury. However, a remarkable feature of rostral parasagittal fluid percussion injury is the occurrence, in the early months post injury, of brief (
Robert S Pomeroy - One of the best experts on this subject based on the ideXlab platform.
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developing a Functional Definition of small scale fisheries in support of marine capture fisheries management in indonesia
JFMR-Journal of Fisheries and Marine Research, 2020Co-Authors: Abdul Halim, Budy Wiryawan, N R Loneragan, Adrian Hordyk, Fedi M A Sondita, Alan T White, Sonny Koeshendrajana, Toni Ruchimat, Robert S PomeroyAbstract:Small-scale capture fisheries have a very important place globally, but unfortunately are still mostly unregulated. Typically, they are defined based on capture fisheries characteristics, technical attributes of fishing vessels, and socio-economic attributes of fishers. Indonesia uses the term ‘small-scale fisher’ (nelayan kecil), currently defined to include fishing boats of ≤ 10 gross tons (GT), which previously covered only boats of ≤ 5 GT. Because small-scale fishers are by law granted a privilege by government to be exempted from fisheries management measures (e.g. fisheries licensing system), its current definition jeopardizes fisheries sustainability and significantly increases the size of unregulated and unreported fisheries. It is also unfair, as it legitimizes the payment of government support to relatively well-o ff fishers. This paper aims to develop a Functional definition of small-scale fisheries (perikanan skala kecil) to guide policy implementation to improve capture fisheries management in Indonesia. A definition of small-scale fisheries is proposed as a fisheries operation, managed at the household level, fishing with or without a fishing boat of < 5 GT, and using fishing gear that is operated by manpower alone. This definition combines attributes of the fishing vessel (GT), the fishing gear (mechanization), and the unit of business decision making (household) to minimize unregulated and unreported fishing and focus government aid on people who are truly poor and vulnerable to social and economic shocks. The terms small-scale fisheries and small-scale fishers must be legally di ff erentiated as the former relates to fisheries management and the latter relates to empowerment of marginalized fishers.
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developing a Functional Definition of small scale fisheries in support of marine capture fisheries management in indonesia
Marine Policy, 2019Co-Authors: Abdul Halim, Budy Wiryawan, N R Loneragan, Adrian Hordyk, Fedi M A Sondita, Alan T White, Sonny Koeshendrajana, Toni Ruchimat, Robert S PomeroyAbstract:Abstract Small-scale capture fisheries have a very important place globally, but unfortunately are still mostly unregulated. Typically, they are defined based on capture fisheries characteristics, technical attributes of fishing vessels, and socio-economic attributes of fishers. Indonesia uses the term ‘small-scale fisher’ (nelayan kecil), currently defined to include fishing boats of
Soroush Zaghi - One of the best experts on this subject based on the ideXlab platform.
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assessment of posterior tongue mobility using lingual palatal suction progress towards a Functional Definition of ankyloglossia
Journal of Oral Rehabilitation, 2021Co-Authors: Soroush Zaghi, Shayan Shamtoob, Cynthia Peterson, Loree Christianson, Zahra Peeran, Brigitte Fung, Triin Jagomägi, Nicole Archambault, Sanda Valcupinkerton, Bridget OconnorAbstract:Background A Functional Definition of ankyloglossia has been based on assessment of tongue mobility using the tongue range of motion ratio (TRMR) with the tongue tip extended towards the incisive papilla (TIP). Whereas this measurement has been helpful in assessing for variations in the mobility of the anterior one-third of the tongue (tongue tip and apex), it may be insufficient to adequately assess the mobility of the posterior two-thirds body of the tongue. A commonly used modification is to assess TRMR while the tongue is held in suction against the roof of the mouth in lingual-palatal suction (LPS). Objective This study aims to explore the utility and normative values of TRMR-LPS as an adjunct to Functional assessment of tongue mobility using TRMR-TIP. Study design Cross-sectional cohort study of 611 subjects (ages: 3-83 years) from the general population. Methods Measurements of tongue mobility using TRMR were performed with TIP and LPS Functional movements. Objective TRMR measurements were compared with subjective self-assessment of resting tongue position, ease or difficulty elevating the tongue tip to the palate, and ease or difficulty elevating the tongue body to the palate. Results There was a statistically significant association between the objective measures of TRMR-TIP and TRMR-LPS and subjective reports of tongue mobility. LPS measurements were much more highly correlated with differences in elevating the posterior body of the tongue as compared to TIP measurements (R2 0.31 vs 0.05, P Conclusions This study validates the TRMR-LPS as a useful Functional metric for assessment of posterior tongue mobility.
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Assessment of posterior tongue mobility using lingual‐palatal suction: Progress towards a Functional Definition of ankyloglossia
Journal of oral rehabilitation, 2021Co-Authors: Soroush Zaghi, Shayan Shamtoob, Cynthia Peterson, Loree Christianson, Sanda Valcu-pinkerton, Zahra Peeran, Brigitte Fung, Triin Jagomägi, Nicole ArchambaultAbstract:Background A Functional Definition of ankyloglossia has been based on assessment of tongue mobility using the tongue range of motion ratio (TRMR) with the tongue tip extended towards the incisive papilla (TIP). Whereas this measurement has been helpful in assessing for variations in the mobility of the anterior one-third of the tongue (tongue tip and apex), it may be insufficient to adequately assess the mobility of the posterior two-thirds body of the tongue. A commonly used modification is to assess TRMR while the tongue is held in suction against the roof of the mouth in lingual-palatal suction (LPS). Objective This study aims to explore the utility and normative values of TRMR-LPS as an adjunct to Functional assessment of tongue mobility using TRMR-TIP. Study design Cross-sectional cohort study of 611 subjects (ages: 3-83 years) from the general population. Methods Measurements of tongue mobility using TRMR were performed with TIP and LPS Functional movements. Objective TRMR measurements were compared with subjective self-assessment of resting tongue position, ease or difficulty elevating the tongue tip to the palate, and ease or difficulty elevating the tongue body to the palate. Results There was a statistically significant association between the objective measures of TRMR-TIP and TRMR-LPS and subjective reports of tongue mobility. LPS measurements were much more highly correlated with differences in elevating the posterior body of the tongue as compared to TIP measurements (R2 0.31 vs 0.05, P Conclusions This study validates the TRMR-LPS as a useful Functional metric for assessment of posterior tongue mobility.
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toward a Functional Definition of ankyloglossia validating current grading scales for lingual frenulum length and tongue mobility in 1052 subjects
Sleep and Breathing, 2017Co-Authors: Audrey Yoon, Soroush Zaghi, Rachel E Weitzman, Clarice S Law, Christian Guilleminault, Stanley Yungchuan LiuAbstract:Purpose Alterations of the lingual frenulum may contribute to oromyofacial dysfunction, speech and swallowing impediments, underdevelopment of the maxillofacial skeleton, and even predispose to sleep breathing disorder. This study aims to assess the utility of existing instruments for evaluation of restricted tongue mobility, describe normal and abnormal ranges of tongue mobility, and provide evidence in support of a reliable and efficient measure of tongue mobility.
Adrian Hordyk - One of the best experts on this subject based on the ideXlab platform.
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developing a Functional Definition of small scale fisheries in support of marine capture fisheries management in indonesia
JFMR-Journal of Fisheries and Marine Research, 2020Co-Authors: Abdul Halim, Budy Wiryawan, N R Loneragan, Adrian Hordyk, Fedi M A Sondita, Alan T White, Sonny Koeshendrajana, Toni Ruchimat, Robert S PomeroyAbstract:Small-scale capture fisheries have a very important place globally, but unfortunately are still mostly unregulated. Typically, they are defined based on capture fisheries characteristics, technical attributes of fishing vessels, and socio-economic attributes of fishers. Indonesia uses the term ‘small-scale fisher’ (nelayan kecil), currently defined to include fishing boats of ≤ 10 gross tons (GT), which previously covered only boats of ≤ 5 GT. Because small-scale fishers are by law granted a privilege by government to be exempted from fisheries management measures (e.g. fisheries licensing system), its current definition jeopardizes fisheries sustainability and significantly increases the size of unregulated and unreported fisheries. It is also unfair, as it legitimizes the payment of government support to relatively well-o ff fishers. This paper aims to develop a Functional definition of small-scale fisheries (perikanan skala kecil) to guide policy implementation to improve capture fisheries management in Indonesia. A definition of small-scale fisheries is proposed as a fisheries operation, managed at the household level, fishing with or without a fishing boat of < 5 GT, and using fishing gear that is operated by manpower alone. This definition combines attributes of the fishing vessel (GT), the fishing gear (mechanization), and the unit of business decision making (household) to minimize unregulated and unreported fishing and focus government aid on people who are truly poor and vulnerable to social and economic shocks. The terms small-scale fisheries and small-scale fishers must be legally di ff erentiated as the former relates to fisheries management and the latter relates to empowerment of marginalized fishers.
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developing a Functional Definition of small scale fisheries in support of marine capture fisheries management in indonesia
Marine Policy, 2019Co-Authors: Abdul Halim, Budy Wiryawan, N R Loneragan, Adrian Hordyk, Fedi M A Sondita, Alan T White, Sonny Koeshendrajana, Toni Ruchimat, Robert S PomeroyAbstract:Abstract Small-scale capture fisheries have a very important place globally, but unfortunately are still mostly unregulated. Typically, they are defined based on capture fisheries characteristics, technical attributes of fishing vessels, and socio-economic attributes of fishers. Indonesia uses the term ‘small-scale fisher’ (nelayan kecil), currently defined to include fishing boats of
