Neurotoxic reactive astrocytes are induced by activated microglia

Liddelow, Shane A.,Guttenplan, Kevin A.,Clarke, Laura E.,Bennett, Frederick C.,Bohlen, Christopher J.,Schirmer, Lucas,Bennett, Mariko L.,Mü,nch, Alexandra E.,Chung, Won-Suk,Peterson, Todd C.,Wilto Nature Publishing Group, a division of Macmillan P 2017 Nature Vol.541 No.7638

<P>Reactive astrocytes are strongly induced by central nervous system (CNS) injury and disease, but their role is poorly understood. Here we show that a subtype of reactive astrocytes, which we termed A1, is induced by classically activated neuroinflammatory microglia. We show that activated microglia induce A1 astrocytes by secreting Il-1 alpha, TNF and C1q, and that these cytokines together are necessary and sufficient to induce A1 astrocytes. A1 astrocytes lose the ability to promote neuronal survival, outgrowth, synaptogenesis and phagocytosis, and induce the death of neurons and oligodendrocytes. Death of axotomized CNS neurons in vivo is prevented when the formation of A1 astrocytes is blocked. Finally, we show that A1 astrocytes are abundant in various human neurodegenerative diseases including Alzheimer's, Huntington's and Parkinson's disease, amyotrophic lateral sclerosis and multiple sclerosis. Taken together these findings help to explain why CNS neurons die after axotomy, strongly suggest that A1 astrocytes contribute to the death of neurons and oligodendrocytes in neurodegenerative disorders, and provide opportunities for the development of new treatments for these diseases.</P>

A Short Test of English Silent Word Reading for English Language Learners

Sylvia C. Kalindi,Catherine Mcbride Chang,Shingfong Chan,Kien Hoa Kevin Chung,Chia Ying Lee,Urs Maurer,Xiuhong Tong 한국아동학회 2015 Child studies in Asia-Pacific context Vol.5 No.2

We developed a test of English silent word reading, following work by Mather, Hammill, Allen, and Roberts (2004) and Bell, McCallum, Krik, Fuller, and McCane-Bowling (2007), in order to tap Hong Kong Chinese children``s reading of English as a foreign language. We created one subtest of individual word reading and another of word reading contextualized within sentences; together, these tests require no more than 10 minutes for administration. In Study 1, we administered the entire test to 552 second grade Hong Kong Chinese children between the ages of 70 and 121 months old, from five different primary schools. The association between the subtests of English silent word reading and contextual reading was positively correlated (.78). In Study 2, 77 Hong Kong Chinese second graders were tested on our newly developed English silent word reading test, together with non-verbal IQ, an English word reading and a Chinese character recognition test (both read aloud). With age and non-verbal IQ statistically controlled, there was a significant correlation between English silent word reading and the more standard English word reading, read aloud, (.78); the association between English silent word reading and Chinese character recognition was also positively correlated (.49). This newly created test is a quick and reliable measure, suitable for both educators and researchers to use to identify poor readers who learn English as a foreign or second language.

A Short Test of English Silent Word Reading for English Language Learners

Kalindi, Sylvia C.,McBride, Catherine,Chan, Shingfong,Chung, Kien Hoa Kevin,Lee, Chia-Ying,Maurer, Urs,Tong, Xiuhong Korean Association of Child Studies 2015 Child studies in Asia-Pacific context Vol.2 No.2

We developed a test of English silent word reading, following work by Mather, Hammill, Allen and Roberts (2004) and Bell, McCallum, Krik, Fuller, and McCane-Bowling (2007), in order to tap Hong Kong Chinese children's reading of English as a foreign language. We created one subtest of individual word reading and another of word reading contextualized within sentences; together, these tests require no more than 10 minutes for administration. In Study 1, we administered the entire test to 552 second grade Hong Kong Chinese children between the ages of 70 and 121 months old, from five different primary schools. The association between the subtests of English silent word reading and contextual reading was positively correlated (.78). In Study 2, 77 Hong Kong Chinese second graders were tested on our newly developed English silent word reading test, together with non-verbal IQ, an English word reading and a Chinese character recognition test (both read aloud). With age and non-verbal IQ statistically controlled, there was a significant correlation between English silent word reading and the more standard English word reading, read aloud, (.78); the association between English silent word reading and Chinese character recognition was also positively correlated (.49). This newly created test is a quick and reliable measure, suitable for both educators and researchers to use to identify poor readers who learn English as a foreign or second language.

Synergistic effect of metal-organic framework-derived boron and nitrogen heteroatom-doped three-dimensional porous carbons for precious-metal-free catalytic reduction of nitroarenes

Van Nguyen, Chi,Lee, Seulchan,Chung, Yongchul G.,Chiang, Wei-Hung,Wu, Kevin C.-W. Elsevier 2019 Applied Catalysis B Vol.257 No.-

<P><B>Abstract</B></P> <P>We report a scalable and controllable synthesis of metal-organic framework (MOF)-derived three-dimensional boron and nitrogen heteroatom-doped porous carbons (3D-BNPCs) and their synergistic effect for metal-free catalytic 4-nitrophenol (4-NP) reduction. The substitution of boron atoms into zeolitic imidazole framework-8 (ZIF-8)-derived nitrogen-doped porous carbon (B-NPC-1200) significantly improves the electrical conductivity and the catalytic 4-NP reduction. We propose the heteroatom-doping of boron, nitrogen and oxygen in the 3D- B-N PC catalysts creates synergistic effect on 4-NP reduction by creating more catalytically active sites. High-Resolution X-ray Photoelectron Spectroscopy (HR-XPS) and Density Functional Theory (DFT) calculations were carried out to confirm and investigate the role of active sites on adsorption of 4-NP molecules in B-NPC-1200. We find that the strongly active sites can only be created based on the synergistic effect between nitrogen, boron and oxygen atoms, and the increased density of the active sites are responsible for the lowering of the apparent activation energy in B-NPC-1200 structure. As synthesized B-NPC-1200 exhibits superior catalytic activities for 4-NP reduction with a low apparent activation energy of 27.0 kJ/mol and a high reaction rate constant of 2.3*10^<SUP>−3</SUP> (s<SUP>-1</SUP>). The catalyst can run five times without decreasing significant catalytic activity. The reduction reactions of various nitroarene compounds have been further tested using the B-N PC-1200 material as the precious-metal-free catalyst.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZIF-derived boron- and nitrogen-co-doped 3-dimensional porous carbon (3D-BNPC) is synthesized for the first time. </LI> <LI> The 3D-NPC shows uniform morphology and extremely high surface area. </LI> <LI> The 3D-NPC catalyst exhibits superior activity for 4-nitrophenol (4-NP) reduction into 4-aminophenol (4-AP). </LI> <LI> Density functional theory (DFT) calculation is studied. </LI> <LI> The co-doping of B with N in the 3D-BNPC catalysts provides the synergistic effect on 4-NP reduction. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Flexor Tendon Rupture Secondary to Gout

Lynn Jeremy V.,Strong Amy L.,Chung Kevin C. 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.5

Extra-articular deposition of monosodium urate crystals is a widely recognized manifestation of gout. However, gouty infiltration of flexor tendons in the hand resulting in tendon rupture is exceedingly rare. This case report highlights a patient with gouty infiltration of flexor tendons in the right middle finger resulting in rupture of both the flexor digitorum profundus and flexor digitorum superficialis. Given the extent of gouty infiltration and need for pulley reconstruction, the patient was treated with two-stage flexor tendon reconstruction. Febuxostat was prescribed preoperatively to limit further deposition of monosodium urate crystals and continued postoperatively to maximize the potential for long-lasting results. Prednisone was prescribed between the first- and second-stage operations to prevent a gout flare while the silicone rod was in place. In summary, tendon rupture secondary to gouty infiltration is the most likely diagnosis in patients with a history of gout presenting with tendon insufficiency.

Learners’ Responses to a Virtual Cadaver Dissection Nerve Course in the COVID Era: A Survey Study

Jeffrey L. Lisiecki,Shepard Peir Johnson,David Grant,Kevin C. Chung 대한성형외과학회 2022 Archives of Plastic Surgery Vol.49 No.5

Background Virtual education is an evolving method for teaching medical learners. During the coronavirus disease 2019 pandemic, remote learning has provided a replacement for conferences, lectures, and meetings, but has not been described as a method for conducting a cadaver dissection. We aim to demonstrate how learners perceive a virtual cadaver dissection as an alternative to live dissection. Methods A virtual cadaver dissection was performed to demonstrate several upper extremity nerve procedures. These procedures were livestreamed as part of an educational event with multimedia and interactive audience questions. Participants were queried both during and after the session regarding their perceptions of this teaching modality. Results Attendance of a virtual dissection held for three plastic surgery training institutions began at 100 and finished with 70 participants. Intrasession response rates from the audience varied between 68 and 75%, of which 75% strongly agreed that they were satisfied with the virtual environment. The audience strongly agreed or agreed that the addition ofmultimedia captions (88%), magnified video loupe views (82%), and split-screen multicast view (64%) was beneficial. Postsession response rate was 27%, and generally reflected a positive perspective about the content of the session. Conclusions Virtual cadaver dissection is an effective modality for teaching surgical procedures and can be enhanced through technologies such as video loupes and multiple camera perspectives. The audience viewed the virtual cadaver dissection as a beneficial adjunct to surgical education. This format may also make in-person cadaver coursesmore effective by improving visualization and allowing for anatomic references to be displayed synchronously.

Expression of the <i>Ciona intestinalis</i> Alternative Oxidase (AOX) in <i>Drosophila</i> Complements Defects in Mitochondrial Oxidative Phosphorylation

Fernandez-Ayala, Daniel J.M.,Sanz, Alberto,Vartiainen, Suvi,Kemppainen, Kia K.,Babusiak, Marek,Mustalahti, Eero,Costa, Rodolfo,Tuomela, Tea,Zeviani, Massimo,Chung, Jongkyeong,O'Dell, Kevin M.C.,Rustin Elsevier 2009 Cell metabolism Vol.9 No.5

<P><B>Summary</B></P><P>Defects in mitochondrial OXPHOS are associated with diverse and mostly intractable human disorders. The single-subunit alternative oxidase (AOX) found in many eukaryotes, but not in arthropods or vertebrates, offers a potential bypass of the OXPHOS cytochrome chain under conditions of pathological OXPHOS inhibition. We have engineered <I>Ciona intestinalis</I> AOX for conditional expression in <I>Drosophila melanogaster.</I> Ubiquitous AOX expression produced no detrimental phenotype in wild-type flies. However, mitochondrial suspensions from AOX-expressing flies exhibited a significant cyanide-resistant substrate oxidation, and the flies were partially resistant to both cyanide and antimycin. AOX expression was able to complement the semilethality of partial knockdown of both <I>cyclope</I> (COXVIc) and the complex IV assembly factor <I>Surf1</I>. It also rescued the locomotor defect and excess mitochondrial ROS production of flies mutated in <I>dj-1</I>β, a <I>Drosophila</I> homolog of the human Parkinson's disease gene <I>DJ1</I>. AOX appears to offer promise as a wide-spectrum therapeutic tool in OXPHOS disorders.</P>