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1.
Chem Commun (Camb) ; 60(48): 6166-6169, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38804671

ABSTRACT

Treatment of 2-methylsulfinylbenzazoles with triflic anhydride in the presence of phenols yields the corresponding 4-(p-hydroxyphenyl)-2-methylsulfanylbenzazoles. This regioselective dehydrative C-H/C-H coupling arylation represents a rare example of functionalizations on the benzene rings of benzo-fused azoles.

2.
J Morphol ; 285(2): e21664, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38361270

ABSTRACT

Although Xenopus Laevis is the most widely used model amphibian, skeletal development of its vertebral column has not been well illustrated so far. The mode of vertebral column development in anurans has been classified into two modes: perichordal and epichordal. Xenopus vertebral column formation is believed to follow the epichordal mode, but this aspect has been underemphasized, and illustrative examples are currently unavailable to the scientific community. This study documents the entire process of vertebral column formation in X. laevis, from the initial neural arch formation to the completion of metamorphosis. These images reveal that the neural arch arises from the dorsal lamina and lateral pedicle primordia, with no strict adherence to an anteroposterior sequence. Unlike other species, Xenopus centrum primordia exclusively form at the expanded ventral margins of neural arches, rather than from the cartilaginous layer surrounding the notochord. These paired centrum primordia then fuse at the ventral midline, dorsal to the notochord, and subsequently the notochord degenerates. This mode of centrum formation differs from the traditional epichordal mode, indicating that Xenopus might have lost the ability to form a cartilaginous layer around the notochord. Instead, the neural arch's ventral margin appears to have evolved to incorporate centrum precursor cells at its base, thereby forming a centrum-like structure compensating for the absence of a true centrum. It is widely accepted that postsacral vertebrae lack centra, only possessing neural arches, and eventually fuse with the hypochord to form the urostyle. However, we have shown that the paired ventral ends of the postsacral vertebrae also fuse at the midline to form a centrum-like structure. This process might extend to the trunk region during centrum formation. In addition to these findings, we offer evolutionary insights into the reasons why Xenopus retains centrum primordia at the base of neural arches.


Subject(s)
Cartilage , Spine , Animals , Xenopus laevis , Metamorphosis, Biological , Embryonic Development
3.
Mod Rheumatol ; 33(6): 1162-1170, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-36399020

ABSTRACT

OBJECTIVES: The objective of the study was to report the efficacy and safety of canakinumab treatment in Japanese patients with systemic juvenile idiopathic arthritis (sJIA) over a 48-week study period. METHODS: Patients were administered canakinumab 4 mg/kg (maximum dose 300 mg) every 4 weeks, with no dose adjustments. The key outcome measures included adapted American College of Rheumatology paediatric (aACR pedi) 30/50/70/90/100 response, proportion of patients with inactive disease, and corticosteroid (CS) tapering. RESULTS: In total, 16/19 (84.2%) patients received canakinumab for ≥96 weeks reaching end-of-study (EOS) visit without premature discontinuation. Regardless of the level of joint involvement at baseline, high aACR pedi responses were observed throughout the study; at the EOS, aACR pedi 90/100 response rates were 84.2%/63.2%, respectively. The proportion of patients who successfully tapered CSs at EOS was 66.7% (12/18), of which 10 patients were steroid-free. The most common adverse events were infections (238.3 events/100 patient-years). Serious adverse events were observed in 52.6%. The event (n=1) adjudicated as possible macrophage activation syndrome was preceded by sJIA flare. No deaths were reported. CONCLUSIONS: Canakinumab treatment resulted in a sustained treatment response in sJIA patients over 48 weeks and was associated with CS tapering in majority of patients. No new safety findings were reported.


Subject(s)
Antirheumatic Agents , Arthritis, Juvenile , Humans , Child , Arthritis, Juvenile/drug therapy , Antibodies, Monoclonal/therapeutic use , East Asian People , Antibodies, Monoclonal, Humanized/therapeutic use , Adrenal Cortex Hormones/therapeutic use , Treatment Outcome , Antirheumatic Agents/therapeutic use
4.
Opt Express ; 25(4): 3445-3453, 2017 Feb 20.
Article in English | MEDLINE | ID: mdl-28241558

ABSTRACT

We report a wavelength division multiplexed time-bin entangled photon pair source in telecom wavelength using a 10 µm radius Si ring resonator. This compact resonator has two add ports and two drop ports. By pumping one add port by a continuous laser, we demonstrate an efficient generation of two-wavelength division multiplexed time-bin entangled photon pairs in the telecom C-band, which come out of one drop port, and are then split into the signal and idler photons via a wavelength filter. The resonator structure enhances four-wave mixing for pair generation. Moreover, we demonstrate the double-port pumping where two counter propagating pump lights are injected to generate entanglement from the two drop ports simultaneously. We successfully observe the highly entangled outputs from both two drop ports. Surprisingly, the count rate at each drop port is even increased by twice that of the single-port pumping. Possible mechanisms of this observation are discussed. Our technique allows for the efficient use of the Si ring resonator and widens its functionality for variety of applications.

5.
Opt Express ; 23(22): 28836-48, 2015 Nov 02.
Article in English | MEDLINE | ID: mdl-26561152

ABSTRACT

Hong-Ou-Mandel (HOM) interference between independent photon sources (HOMI-IPS) is the fundamental block for quantum information processing. All the previous HOMI-IPS experiments were carried out in time-domain, however, the spectral information during the interference was omitted. Here, we investigate the HOMI-IPS in spectral domain using the recently developed fast fiber spectrometer, and demonstrate the spectral distribution during the HOM interference between two heralded single-photon sources, and two thermal sources. This experiment not only can deepen our understanding of HOMI-IPS from the viewpoint of spectral domain, but also presents a tool to test the theoretical predictions of HOMI-IPS using spectrally engineered sources.

6.
Opt Express ; 23(2): 1103-13, 2015 Jan 26.
Article in English | MEDLINE | ID: mdl-25835870

ABSTRACT

We demonstrate time-bin entanglement generation in telecom wavelength using a 7 µm radius Si micro-ring resonator pumped by a continuous wave laser. The resonator structure can enhance spontaneous four wave mixing, leading to a photon pair generation rate of about 90-100 Hz with a laser pump power of as low as -3.92 dBm (0.41 mW). We succeed in observing time-bin entanglement with the visibility over 92%. Moreover, wavelength-tunability of the entangled photon pair is demonstrated by changing the operation temperature.

7.
Org Lett ; 14(18): 4794-7, 2012 Sep 21.
Article in English | MEDLINE | ID: mdl-22946568

ABSTRACT

An efficient protocol for the aza-Diels-Alder reaction of electron-deficient 1,3-dienes with unactivated imines in the presence of a cationic cobalt(III) porphyrin complex was developed. The transformation proceeded smoothly to afford the desired piperidine scaffold within 2 h at ambient temperature. Highly chemoselective cycloaddition of imines with dienes in the presence of a variety of carbonyl compounds was also demonstrated.


Subject(s)
Aza Compounds/chemistry , Cobalt/chemistry , Metalloporphyrins/chemistry , Catalysis , Combinatorial Chemistry Techniques , Molecular Structure
8.
J Org Chem ; 75(13): 4337-43, 2010 Jul 02.
Article in English | MEDLINE | ID: mdl-20545371

ABSTRACT

A facile route to homoallyl alcohols bearing a trisubstituted double bond has been devised. The palladium-catalyzed reactions of aryl halides with the alcohols thus synthesized result in regiospecific allyl transfer from the alcohols to aryl halides via retro-allylation, providing allylarenes having two substituents at the 1 and 2 positions of the allyl moiety. Optically active homoallyl alcohols transfer their chirality at the hydroxylated carbon to the benzylic carbon of the product.

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