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1.
Digestion ; : 1-10, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38763127

RESUMEN

INTRODUCTION: Carbazochrome sodium sulfonate (CSS) is a hemostatic agent that reduces capillary permeability and enhances capillary resistance. However, its specific effects on colorectal endoscopic submucosal dissection (ESD) outcomes remain uncertain. This study aimed to assess the risk factors for post-ESD bleeding and the effect of CSS on colorectal ESD outcomes. METHODS: First, we retrospectively analyzed the risk factors for post-ESD bleeding using data from 1,315 lesions in 1,223 patients who underwent ESD for superficial colorectal neoplasms at eight institutions. Second, patients were divided into CSS and non-CSS groups using propensity score matching, and their outcomes from colorectal ESD were analyzed. RESULTS: The risk factors for post-colorectal ESD bleeding were identified as age of ≥70 years, tumor located in the rectum, tumor size of ≥40 mm, and post-ESD defect unclosure in both univariate and multivariate analyses. The CSS and non-CSS groups each consisted of 423 lesions after propensity score matching. The post-colorectal ESD bleeding rate was 3.5% (15/423) and 3.3% (14/423) in the CSS and non-CSS groups, respectively, indicating no significant differences. Among patients with the high-risk factors for post-ESD bleeding, the administration of CSS also did not demonstrate a significant reduction in the post-ESD bleeding rate compared to the non-CSS group. CONCLUSION: CSS administration is ineffective in preventing post-colorectal ESD bleeding in both the general population and individuals at a high risk for such bleeding. Our results indicate the necessity to reconsider the application of CSS for preventing post-colorectal ESD bleeding.

2.
J Am Chem Soc ; 145(49): 27089-27094, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37967336

RESUMEN

Carbon-carbon σ-single bonds are crucial for constructing molecules like ethane derivatives (R3C-CR3), which are composed of tetrahedral four-coordinate carbons. Molecular functions, such as light absorption or emission, originate from the π-bonds existing in ethylene derivatives (R2C═CR2). In this study, a relatively stable cyclopentane-1,3-diyl species with π-single bonding system (C-π-C) with planar four-coordinate carbons is constructed. This diradicaloid is energetically more stable than the corresponding σ-single bonding system. The π-electron single bonding system provides deeper insights into the chemical bonding and the physical properties derived from the small energy gaps between the bonding and antibonding molecular orbitals.

3.
J Reprod Dev ; 69(5): 279-290, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37690839

RESUMEN

Progesterone (P) is a well-known enhancer of hyperactivation which is associated with the success of in vitro fertilization (IVF). In this study, we examined whether P-enhanced hyperactivation affected IVF success in rats. When rat spermatozoa were exposed to 10, 20, and 40 ng/ml P, 20 ng/ml P enhanced hyperactivation via the membrane progesterone receptor. In addition, the enhancement of hyperactivation by 20 ng/ml P was regulated by phospholipase C, transmembrane adenylate cyclase, and protein kinase A. However, 20 ng/ml P did not affect IVF success. These results suggest that 20 ng/ml P enhances rat spermatozoal hyperactivation through non-genomic pathways. Because the concentration of P changes during the estrous cycle, it seems that rat spermatozoa are hyperactivated in response to the oviductal environment. However, the effect of 20 ng/ml P does not seem to fully capacitate spermatozoa.


Asunto(s)
Progesterona , Capacitación Espermática , Masculino , Humanos , Femenino , Ratas , Animales , Progesterona/metabolismo , Espermatozoides/metabolismo , Fertilización In Vitro , Oviductos , Motilidad Espermática
4.
Chemistry ; 29(42): e202301009, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37132401

RESUMEN

Unique spin-spin (magnetic) interactions, ring-size effects on ground-state spin multiplicity, and in-plane aromaticity has been found in localized 1,3-diradicals embedded in curved benzene structures such as cycloparaphenylene (CPP). In this study, we characterized the magnetic interactions in a tetraradical consisting of two localized 1,3-diradical units connected by p-quaterphenyl within a curved CPP skeleton by electron paramagnetic resonance (EPR) spectroscopy and quantum chemical calculations. Persistent triplet species with zero-field splitting parameters similar to those of a triplet 1,3-diphenylcyclopentane-1,3-diyl diradical were observed by continuous wave (CW) or pulsed X-band EPR measurements. The quintet state derived from the ferromagnetic interaction between the two triplet diradical moieties was not detected at 20 K under glassy matrix conditions. At the B3LYP/6-31G(d) level of theory, the singlet state was lower in energy than the triplet and quintet states. These findings will aid in the development of open-shell species for material science application.

5.
Sensors (Basel) ; 23(9)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37177645

RESUMEN

Optimizing the bias modulation of a fiber-optic gyroscope is crucial to improving its precision. In this study, we propose and demonstrate the use of multiple harmonics of sinusoidal modulation as an intermediate alternative to the widely used modulation methods: sinusoidal and square-wave modulation. We show that this alternative integrates the advantages of each modulation method by providing a smooth modulation that produces a clean, spike-free output and a satisfactory signal-to-noise ratio. By using three harmonics of modulation in combination with a high frequency to reduce thermal phase noise, we obtained an angular random walk of 5.2(2)µdeg/h and a bias instability of ∼10µdeg/h. This is the highest performance ever reported for fiber-optic gyroscopes.

6.
Phys Rev Lett ; 129(22): 223401, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493443

RESUMEN

We report the realization of a Bose-Einstein condensate of europium atoms, which is a strongly dipolar species with unique properties, a highly symmetric [Xe]4f^{7}6s^{2} ^{8}S_{7/2} electronic ground state and a hyperfine structure. By means of evaporative cooling in a crossed optical dipole trap, we produce a condensate of ^{151}Eu containing up to 5×10^{4} atoms. We estimate the scattering length of ^{151}Eu to be a_{s}=110(4) a_{B} after comparing the velocities of expansion of condensates to different orientations of the atomic magnetic moments, where a_{B} is the Bohr radius. We observe deformation of the condensate in the vicinity of the Feshbach resonance at 1.32 G with a width of 10 mG.


Asunto(s)
Frío , Europio , Pinzas Ópticas , Transición de Fase , Vibración
7.
Org Lett ; 23(13): 4955-4959, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34048267

RESUMEN

In this study, the SOMO-HOMO conversion has been shown for the first time in triplet carbenes embedded in cycloparaphenylene units. The high-lying HOMO originating from the curved π-conjugated system and the low-lying SOMO-1 originating due to the small carbene angle are the key to endowing this interesting electronic configuration. Furthermore, simple planar triplet carbenes such as fluorenylidene were found to possess SOMO-HOMO energy-converted electronic configurations.

8.
J Am Chem Soc ; 143(19): 7426-7439, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33900091

RESUMEN

Curved π-conjugated molecules and open-shell structures have attracted much attention from the perspective of fundamental chemistry, as well as materials science. In this study, the chemistry of 1,3-diradicals (DRs) embedded in curved cycloparaphenylene (CPPs) structures, DR-(n+3)CPPs (n = 0-5), was investigated to understand the effects of the curvature and system size on the spin-spin interactions and singlet versus triplet state, as well as their unique characteristics such as in-plane aromaticity. A triplet ground state was predicted for the larger 1,3-diradicals, such as the seven- and eight-paraphenylene-unit-containing diradicals DR-7CPP (n = 4) and DR-8CPP (n = 5), by quantum chemical calculations. The smaller-sized diradicals DR-(n+3)CPPs (n = 0-3) were found to possess singlet ground states. Thus, the ground-state spin multiplicity is controlled by the size of the paraphenylene cycle. The size effect on the ground-state spin multiplicity was confirmed by the experimental generation of DR-6CPP in the photochemical denitrogenation of its azo-containing precursor (AZ-6CPP). Intriguingly, a unique type of in-plane aromaticity emerged in the smaller-sized singlet states such as S-DR-4CPP (n = 1), as proven by nucleus-independent chemical shift calculations (NICS) and an analysis of the anisotropy of the induced current density (ACID), which demonstrate that homoconjugation between the 1,3-diradical moiety arises because of the curved and distorted bonding system.

9.
Drug Metab Pharmacokinet ; 35(3): 266-273, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32303459

RESUMEN

Lamotrigine (LTG) is an important antiepileptic drug for the treatment of seizures in pregnant women with epilepsy. However, it is not known if the transport of LTG into placental cells occurs via a carrier-mediated pathway. The aim of this study was to investigate the uptake properties of LTG into placental cell lines (BeWo and JEG-3), and to determine the involvement of organic cation transporters (OCTs, SLC22A1-3) and organic cation/carnitine transporter (OCTNs, SLC22A4-5) in the uptake process. The uptake of LTG at 37 °C was higher than that at 4 °C. OCT1 and OCTNs were detected in both cell lines. The uptake of LTG was not greatly affected by the extracellular pH, Na+-free conditions, or the presence of l-carnitine, suggesting that OCTNs were not involved. Although several potent inhibitors of OCTs (chloroquine, imipramine, quinidine, and verapamil) inhibited LTG uptake, other typical inhibitors had no effect. In addition, siRNA targeted to OCT1 had no significant effect on LTG uptake. The mRNA expression in human term placenta followed the order OCTN2 > OCT3 > OCTN1 > OCT1 ≈ OCT2. These observations suggested that LTG uptake into placental cells was carrier-mediated, but that OCTs and OCTNs were not responsible for the placental transport process.


Asunto(s)
Lamotrigina/metabolismo , Proteínas de Transporte de Catión Orgánico/metabolismo , Transporte Biológico , Células Cultivadas , Humanos
10.
Endosc Int Open ; 7(12): E1768-E1772, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31828215

RESUMEN

Background and study aims Needle tract seeding during endoscopic ultrasound fine-needle biopsy (EUS-FNB) remains a concern. We investigated whether such seeding occurred in a patient with pancreatic ductal adenocarcinoma (PDA). Patient and methods Surgically resected and EUS-FNB-derived specimens were genotyped to determine if a gastric wall tumor that emerged 3 years after curative resection of an early-stage PDA was clonally related to the original tumor. Results The gastric tumor histologically resembled the primary PDA; the lesions also shared KRAS , SMAD4 , and RNF43 mutations. Genotyping of the preoperative EUS-FNB specimen, in which cancer was not detected, nevertheless revealed mutations that were identical to those in the resected primary and recurrent tumors. While the primary PDA had a low frequency of mutant SMAD4 , such mutations were highly prevalent in both the EUS-FNB and recurrent tumor specimens. Conclusions The genetic lineages of sampled tissues from our patient revealed that needle tract seeding may have incidentally occurred when a subset of neoplastic cells within a heterogeneous tumor ( i. e. , an aggressive clone) was targeted during EUS-FNB.

11.
J Obstet Gynaecol Res ; 44(1): 171-174, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29094482

RESUMEN

Edwardsiella tarda (E. tarda) is a rare pathogen in humans, especially during the peripartum period. Only a few cases of fatal neonatal infection with E. tarda have been reported. Herein, we describe a case of maternal septicemia caused by E. tarda following peripartum chorioamnionitis. The mother developed septic shock, disseminated intravascular coagulation and a post-cesarean wound hematoma with abscess. Her condition improved with multidisciplinary therapy including blood transfusion, antimicrobial agents, recombinant thrombomodulin and surgical debridement. E. tarda was isolated from the maternal blood, cesarean wound and neonatal skin, pharynx and gastric fluid. This case demonstrates that peripartum infection with E. tarda is a rare but life-threatening condition, not only for the neonate but also for the mother.


Asunto(s)
Corioamnionitis , Edwardsiella tarda/patogenicidad , Infecciones por Enterobacteriaceae , Feto/microbiología , Periodo Periparto , Complicaciones Infecciosas del Embarazo , Choque Séptico , Corioamnionitis/microbiología , Corioamnionitis/terapia , Edwardsiella tarda/aislamiento & purificación , Infecciones por Enterobacteriaceae/complicaciones , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/terapia , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/terapia , Choque Séptico/complicaciones , Choque Séptico/microbiología , Choque Séptico/terapia
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