Epstein‐Barr virus (EBV) infection is prevalent in global population and associated with multiple malignancies and autoimmune diseases. During the infection, EBV‐harbored or infected cell‐expressing ...antigen could elicit a variety of antibodies with significant role in viral host response and pathogenesis. These antibodies have been extensively evaluated and found to be valuable in predicting disease diagnosis and prognosis, exploring disease mechanisms, and developing antiviral agents. In this review, we discuss the versatile roles of EBV antibodies as important biomarkers for EBV‐related diseases, potential driving factors of autoimmunity, and promising therapeutic agents for viral infection and pathogenesis.
Mutations in the proline-rich transmembrane protein 2 （PRRT2） are associated with paroxysmal kinesigenic dys- kinesia （PKD） and several other paroxysmal neurological diseases, but the PRRT2 function ...and pathogenic mecha- nisms remain largely obscure. Here we show that PRRT2 is a presynaptic protein that interacts with components of the SNARE complex and downregulates its formation. Loss-of-function mutant mice showed PKD-like phenotypes triggered by generalized seizures, hyperthermia, or optogenetic stimulation of the cerebellum. Mutant mice with spe- cific PRRT2 deletion in cerebellar granule cells （GCs） recapitulate the behavioral phenotypes seen in Prrt2-null mice. Furthermore, recording made in cerebellar slices showed that optogenetic stimulation of GCs results in transient elevation followed by suppression of Purkinje cell firing. The anticonvulsant drug carbamazepine used in PKD treat- ment also relieved PKD-like behaviors in mutant mice. Together, our findings identify PRRT2 as a novel regulator of the SNARE complex and provide a circuit mechanism underlying the PRRT2-related behaviors.
We present high spatial resolution ALMA observations of vibrational transitions of HC3N toward Orion KL in the 214-247 GHz frequency band. 41 transitions of HC3N in 7 vibrationally excited states, ...and 23 transitions of 13C isotopologues of HC3N in 2 vibrational states are detected. The line images show that vibrationally excited HC3N lines originate mainly from the hot core of Orion and IRc7. The images of HC3N vibrationally excited lines show that the line emission peaks associated with the hot core move from south to northeast as increases. Based on multiple transitions of each vibrationally excited state, we performed local thermodynamic equilibrium calculations in the XCLASS suite toward the hot core and IRc7 positions. Generally, transitions in highly excited states have higher rotational temperatures and lower column densities. The rotational temperatures and column densities of the hot core range from 93 to 321 K, and from to cm−2, respectively. Lower rotational temperatures ranging from 88 to 186 K and column densities from to cm−2 are obtained toward IRc7. The facts that the hot core emission peaks of vibrationally excited HC3N lines move from south to northeast with increasing , and that higher-energy HC3N lines have higher rotational temperatures and lower column densities, appear to support that the hot core is externally heated. The emission peaks are moving along the major axis of the SiO outflow, which may indicate that higher-energy HC3N transitions are excited by interaction between pre-existing dense medium and shocks generated by SiO outflows.
Abstract
Protostellar outflows and jets are almost ubiquitous characteristics during the mass accretion phase and encode the history of stellar accretion, complex organic molecule (COM) formation, ...and planet formation. Episodic jets are likely connected to episodic accretion through the disk. Despite the importance, studies on episodic accretion and ejection links have not been done yet in a systematic fashion using high-sensitivity and high-resolution observations. To explore episodic accretion mechanisms and the chronologies of episodic events, we investigated 39 fields containing protostars with Atacama Large Millimeter/submillimeter Array observations of CO, SiO, and 1.3 mm continuum emission. We detected SiO emission in 19 fields, where 17 sources are driving molecular jets. Jet velocities, mass-loss rates, mass accretion rates, and periods of accretion events appear to have some dependence on the driving forces of the jet (e.g., bolometric luminosity, envelope mass). Next, velocities and mass-loss rates appear to be somewhat correlated with the surrounding envelope mass, suggesting that the presence of high mass around protostars increases the ejection–accretion activity. We determine mean periods of ejection events of 20–175 yr for our sample, which could be associated with perturbation zones of ∼2−25 au extent around the protostars. In addition, mean ejection periods show an apparent anticorrelation with the envelope mass, where high accretion rates may trigger more frequent ejection events. The observed periods of outburst/ejection are much shorter than the freezeout timescale of the simplest COMs like CH
3
OH, suggesting that episodic events could affect the ice–gas balance inside and around the snowline.
Glioma is the most common and aggressive tumor in the adult brain. Recent studies have indicated that Zinc finger DHHC-type palmitoyltransferases (ZDHHCs) play vital roles in regulating the ...progression of glioma. ZDHHC15, a member of the ZDHHCs family, participates in various physiological activities in the brain. However, the biological functions and related mechanisms of ZDHHC15 in glioma remain poorly understood.
Data from multiple glioma-associated datasets were used to investigate the expression profiles and potential biological functions of ZDHHC15 in glioma. Expression of ZDHHC15 and its association with clinicopathological characteristics in glioma were validated by quantitative reverse transcription PCR (RT-qPCR) and immunohistochemical experiments. GO enrichment analysis, KEGG analysis, GSEA analysis, CCK-8, EdU, transwell, and western blotting assays were performed to confirm the functions and mechanism of ZDHHC15 in glioma. Moreover, we performed Kaplan-Meier analysis and Cox progression analysis to explore the prognostic significance of ZDHHC15 in glioma patients.
ZDHHC15 expression was significantly up-regulated in glioma and positively associated with malignant phenotypes. Results from the GO and KEGG enrichment analysis revealed that ZDHHC15 was involved in regulating cell cycle and migration. Knockdown of ZDHHC15 inhibited glioma cell proliferation and migration, while overexpression of ZDHHC15 presented opposite effects on glioma cells. Besides, results from GSEA analysis suggested that ZDHHC15 was enriched in STAT3 signaling pathway. Knockdown or overexpression of ZDHHC15 indeed affected the activation of STAT3 signaling pathway. Additionally, we identified ZDHHC15 as an independent prognostic biomarker in glioma, and higher expression of ZDHHC15 predicted a poorer prognosis in glioma patients.
Our findings suggest that ZDHHC15 promotes glioma malignancy and can serve as a novel prognostic biomarker for glioma patients. Targeting ZDHHC15 may be a promising therapeutic strategy for glioma.
We present Atacama Large Millimeter/submillimeter Array observations of the CO (J = 2 − 1) line emission from a protoplanetary disk around T-Tauri star SU Aurigae (hereafter SU Aur). Previous ...observations in optical and near-infrared wavelengths find a unique structure in SU Aur. One of the highlights of the observational results is that an extended tail-like structure is associated with the disk, indicating mass transfer from or into the disk. Here we report the discovery of the counterpart of the tail-like structure in CO gas extending more than 1000 au long. Based on geometric and kinematic perspectives, both of the disk and the tail-like structure components physically connect to each other. Several theoretical studies predicted the observed tail-like structure via the following possible scenarios: (1) a gaseous stream from the molecular cloud remnant, (2) collision with a (sub)stellar intruder or a gaseous blob from the ambient cloud, and (3) ejection of a planetary or brown dwarf mass object due to gravitational instability via multibody gravitational interaction. Since the tail-like structures associated with the SU Aur disk are a new example following RW Aurigae, some disks may experience the internal or external interaction and drastically lose mass during disk evolution.
C‐aryl glycosides are popular basic skeletons in biochemistry and pharmaceutical chemistry. Herein, ruthenium‐catalyzed highly stereo‐ and site‐selective ortho‐ and meta‐CAr−H glycosylation is ...described. A series of C‐aryl pyranosides and furanosides were synthesized by this method. The strategy showed good substrate scope, and various N‐heterocyclic directing groups were compatible with the reaction system. A mechanistic study suggested that the key pathway of ortho‐CAr−H glycosylation might involve oxidative addition/reduction elimination, whereas aryl meta‐C−H glycosylation was mediated by σ‐activation. Density functional theory calculations also showed that the high stereoselectivity of meta‐CAr−H glycosylation was due to steric hindrance.
A series of C‐aryl pyranosides and furanosides were synthesized by ruthenium‐catalyzed ortho‐ and meta‐CAr−H glycosylation. Mechanistic studies suggest that the key pathway of ortho‐CAr−H glycosylation involves an oxidative addition/reductive elimination process, while aryl meta‐C−H glycosylation is mediated by σ‐activation. DFT calculations showed that steric hindrance is responsible for the high stereoselectivity of meta‐CAr−H glycosylation.
Stellar feedback from high-mass stars (e.g., H ii regions) can strongly influence the surrounding interstellar medium and regulate star formation. Our new ALMA observations reveal sequential ...high-mass star formation taking place within one subvirial filamentary clump (the G9.62 clump) in the G9.62+0.19 complex. The 12 dense cores (MM1-MM12) detected by ALMA are at very different evolutionary stages, from the starless core phase to the UC H ii region phase. Three dense cores (MM6, MM7/G, MM8/F) are associated with outflows. The mass-velocity diagrams of the outflows associated with MM7/G and MM8/F can be well-fit by broken power laws. The mass-velocity diagram of the SiO outflow associated with MM8/F breaks much earlier than other outflow tracers (e.g., CO, SO, CS, HCN), suggesting that SiO traces newly shocked gas, while the other molecular lines (e.g., CO, SO, CS, HCN) mainly trace the ambient gas continuously entrained by outflow jets. Five cores (MM1, MM3, MM5, MM9, MM10) are massive starless core candidates whose masses are estimated to be larger than 25 M☉, assuming a dust temperature of ≤20 K. The shocks from the expanding H ii regions ("B" and "C") to the west may have a great impact on the G9.62 clump by compressing it into a filament and inducing core collapse successively, leading to sequential star formation. Our findings suggest that stellar feedback from H ii regions may enhance the star formation efficiency and suppress low-mass star formation in adjacent pre-existing massive clumps.
We report the first detection of radio recombination lines (RRLs) of ions heavier than helium. In a highly sensitive multi-band (12–50 GHz) line survey toward Orion KL with the TianMa 65-m Radio ...Telescope (TMRT), we successfully detected more than fifteen unblended
α
lines of RRLs of singly ionized species (X
II
) recombined from X
III
. The
Ka
-band (26–35 GHz) spectrum also shows tentative signals of
β
lines of ions. The detected lines can be successfully crossmatched with the rest frequencies of RRLs of C
II
and/or O
II
. This finding greatly expands the scope of our understanding of ion RRLs, since prior to this work, only two blended lines (105
α
and 121
α
) of He
II
had been reported. Our detected lines can be fitted simultaneously under assumption of local thermodynamic equilibrium (LTE). An abundance of C
III
and O
III
of 8.8×10
−4
was obtained, avoiding the complexities of optical and infrared observations and the blending of RRLs of atoms. It is consistent with but approaches the upper bound of the value (10
−4
–10
−3
) estimated from optical and infrared observations. The effects of dielectronic recombination may contribute to enhancing the level populations even at large
n
. We expect future observations using radio interferometers could break the degeneracy between C and O, while also helping to reveal the ionization structure and dynamical evolution of various ionized regions.
Magnetic field plays a crucial role in shaping molecular clouds and regulating star formation, yet the complete information on the magnetic field is not well constrained owing to the limitations in ...observations. We study the magnetic field in the massive infrared dark cloud G035.39-00.33 from dust continuum polarization observations at 850 m with SCUBA-2/POL-2 at JCMT for the first time. The magnetic field tends to be perpendicular to the densest part of the main filament (FM), whereas it has a less defined relative orientation in the rest of the structure, where it tends to be parallel to some diffuse regions. A mean plane-of-the-sky magnetic field strength of ∼50 G for FM is obtained using the Davis-Chandrasekhar-Fermi method. Based on 13CO (1-0) line observations, we suggest a formation scenario of FM due to large-scale (∼10 pc) cloud-cloud collision. Using additional NH3 line data, we estimate that FM will be gravitationally unstable if it is only supported by thermal pressure and turbulence. The northern part of FM, however, can be stabilized by a modest additional support from the local magnetic field. The middle and southern parts of FM are likely unstable even if the magnetic field support is taken into account. We claim that the clumps in FM may be supported by turbulence and magnetic fields against gravitational collapse. Finally, we identified for the first time a massive (∼200 M ), collapsing starless clump candidate, "c8," in G035.39-00.33. The magnetic field surrounding "c8" is likely pinched, hinting at an accretion flow along the filament.
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