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1.
Beilstein J Org Chem ; 20: 2691-2703, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39469295

RESUMEN

In this study, we develop the synthesis methods of fluoroalkenes and fluoroenynes via Suzuki-Miyaura and Sonogashira cross-coupling reactions using novel multihalogenated fluorovinyl ethers, which are easily prepared from the reaction between phenols and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane). These reactions make use of the unique structure of multihalogenated fluorovinyl ethers, which contains a reactive bromine atom, to afford a series of fluoroalkenes and fluoroenynes in moderate to high yields.

2.
Sci Rep ; 14(1): 20442, 2024 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227640

RESUMEN

Govetto's staging system (stages 1-4) for epiretinal membrane (ERM) based on optical coherence tomography images is a useful predictor of monocular visual function; however, an association between Govetto's stage and binocular vision has not been reported. This study aimed to investigate the factors associated with Govetto's stage among the monocular and binocular parameters. This retrospective study included consecutive patients with treatment-naïve eyes with unilateral ERM without pseudo-hole. We investigated Govetto's stage, degrees of aniseikonia and metamorphopsia, foveal avascular zone area, central retinal and choroidal thickness, vertical ocular deviation, stereopsis, and binocular single vision (BSV). We compared the parameters between the BSV-present and BSV-absent groups and investigated correlations between Govetto's stage and the monocular and binocular parameters. Twenty-eight eyes of 28 patients were examined (age, 66.6 ± 10.2 years). In multivariate correlation analyses, Govetto's stage correlated with BSV (P = 0.04, ß = - 0.36) and central retinal thickness (P < 0.001, ß = 0.74). Of the eyes, 18 were assigned to the BSV-present group and 10 to the BSV-absent group. Govetto's stage was significantly more advanced in the BSV-absent group than in the BSV-present group (3.2 ± 0.8 vs 2.5 ± 0.7, P = 0.03). Of the 28 patients, 11 (39%) showed small-angle vertical deviations (1-12Δ). In conclusion, our findings showed that Govetto's stage correlated with binocular vision in patients with monocular ERM. Govetto's staging is a useful parameter for predicting not only monocular but also binocular vision.


Asunto(s)
Membrana Epirretinal , Tomografía de Coherencia Óptica , Visión Binocular , Humanos , Anciano , Masculino , Femenino , Visión Binocular/fisiología , Membrana Epirretinal/fisiopatología , Membrana Epirretinal/diagnóstico por imagen , Membrana Epirretinal/patología , Tomografía de Coherencia Óptica/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Agudeza Visual/fisiología , Retina/fisiopatología , Retina/diagnóstico por imagen , Retina/patología , Anciano de 80 o más Años
3.
Chem Pharm Bull (Tokyo) ; 72(9): 775, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39218700

Asunto(s)
Humanos
4.
Chem Pharm Bull (Tokyo) ; 72(9): 794-799, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39218704

RESUMEN

Recently, remarkable progress has been achieved in artificial intelligence (AI), including machine learning. Various AI models have been proposed for drug discovery, including the design of small molecules, activity prediction, and three-dimensional (3D) structure prediction of proteins. AI consists of diverse elements, including information retrieval and machine learning, and can be used in a wide range of drug discovery scenarios. In this review, we focused on AI for small-molecule drug discovery with respect to molecular design, activity prediction, and prediction of the binding poses of compounds to target molecules. We also discussed the applications of AI in academic drug discovery.


Asunto(s)
Inteligencia Artificial , Quimioinformática , Descubrimiento de Drogas , Humanos , Aprendizaje Automático , Bibliotecas de Moléculas Pequeñas/química
5.
Eye (Lond) ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060342

RESUMEN

BACKGROUND/OBJECTIVES: To investigate whether the corrective effect differs between upward and downward transpositions or between exotropia and esotropia in vertical transposition accompanied by horizontal rectus muscle recession-resection. SUBJECTS/METHODS: This prospective study investigated 41 patients with concomitant exotropia or esotropia with small-angle vertical deviation who underwent unilateral vertical transposition accompanied by horizontal rectus muscle recession-resection and were followed up for 1 year postoperatively. We analysed the vertical deviation corrective effect, defined as the corrective amount per displacement distance (°/tendon width [TW]). We compared the corrective effects between upward and downward transpositions and between exotropia and esotropia. Additionally, we investigated the correlation between the corrective effect and the studied parameters. RESULTS: The 1-year vertical corrective effect was 5.2 ± 4.6° (9.0 ± 8.1 prism dioptres [Δ])/TW. The 1-year vertical corrective effect of upward transposition (7.9 ± 4.0° [13.8 ± 7.0Δ]/TW) was higher than that of the downward transposition (3.9 ± 4.4° [6.8 ± 7.7Δ]/TW, P = 0.009). In contrast, upward and downward transposition did not differ between exotropia and esotropia (P = 0.62). Multivariate analyses revealed that the 1-year vertical corrective effect correlated with the vertical transposition direction (upward or downward) and preoperative vertical deviation but did not correlate with the disease type (exotropia or esotropia). The 1-year motor success (vertical deviation ≤ 5Δ) rate was 89%. CONCLUSION: The vertical corrective effect of vertical transposition accompanied by horizontal rectus muscle recession-resection is greater in upward transposition than in downward transposition; however, it does not differ between exotropia and esotropia.

6.
Beilstein J Org Chem ; 20: 1341-1347, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887571

RESUMEN

A novel Rh-catalyzed one-pot homo-coupling reaction of aryl Grignard reagents was achieved. The reaction with bromobenzenes having an electron-donating group or a halogen substituent gave the corresponding homo-coupling products in good yields, although the reaction using heterocyclic or aliphatic bromides scarcely proceeded. A Rh(III)-bis(aryl) complex, which might be formed from RhCl(PPh3)3 and the aryl Grignard reagents, plays an important role in giving the homo-coupling products in this reaction. Furthermore, we applied the reaction to the synthesis of a novel inhibitor for integrins which is critical for several diseases.

7.
ACS Omega ; 9(24): 26275-26284, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38911753

RESUMEN

Yb(OTf)3 promoted the Krapcho decarboxylation of 2,2-difluoro-3-oxopropanoate, and a subsequent aldol reaction was achieved. This process is the first example of generating difluoroenolates through a decarboxylation-type process, and a large number of carbonyl compounds are applicable to the aldol reaction. The protocol is a complete one-pot reaction that uses the bench-stable and nonhygroscopic 2,2-difluoro-3-oxopropanoate to generate the difluoroenolate. This strategy has been applied for the synthesis of CF2-containing bioactive GABAB agonists, contributing to drug design.

8.
Drug Metab Pharmacokinet ; 56: 101005, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663182

RESUMEN

We previously reported novel benzyl-ether derivatives with an imidazole ring and a hydroxyl group (A-01) or carboxyl group (B-01) and esters (2 esters of A-01, and 7 esters of B-01) as pharmacokinetics (PK) boosters. This study demonstrates how these ester compounds embody the concept of a safe pharmacokinetic booster, with potent and transient inhibition of CYP3A4-mediated drug metabolism. As a model CYP3A4 substrate and CYP3A4 enzyme, midazolam (MDZ) and rat liver microsomes were used. A-01 inhibited MDZ metabolism significantly, while B-01 induced only slight inhibition. Although rat liver microsomes hydrolyzed the ester compounds over time, several ester compounds strongly inhibited MDZ metabolism. Due to the significant activity of A-01, A-01 esters affected MDZ metabolism, irrespective of hydrolysis state. Time-dependent inhibition evaluation indicated that the B-01 ester inhibition is not mechanism-based, as hydrolysis eliminated MDZ metabolism inhibition. We report that the B-01 esters significantly inhibit CYP3A4-mediated drug metabolism, and upon hydrolysis this property is eliminated. In conclusion, B-01 ester compounds may be safe PK boosters with antedrug characteristics.


Asunto(s)
Inhibidores del Citocromo P-450 CYP3A , Citocromo P-450 CYP3A , Microsomas Hepáticos , Midazolam , Animales , Citocromo P-450 CYP3A/metabolismo , Microsomas Hepáticos/metabolismo , Midazolam/metabolismo , Midazolam/farmacocinética , Ratas , Inhibidores del Citocromo P-450 CYP3A/farmacología , Masculino , Ratas Sprague-Dawley , Ésteres/química , Ésteres/metabolismo
9.
Acute Med Surg ; 11(1): e943, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500639

RESUMEN

Background: Several reports on organ injury and death due to incorrect chest tube insertion exist; however, reports on the chest tube penetrating the liver and reaching the inferior vena cava are limited. Case Presentation: A 79-year-old man presented with a clamped tube because of massive bleeding from the tube following right chest tube replacement in the hospital of origin. The tube entered the inferior vena cava from the hepatic parenchyma via the right hepatic vein and was removed 15 h later because his hemodynamics stabilized. A ruptured pseudoaneurysm necessitated further transcatheter arterial embolism on the second hospitalization day, and the patient was transferred back to the referring hospital on day 17. Conclusion: Liver injury caused by an inferior vena cava misinsertion-associated chest tube can be treated with elective surgery in anticipation of the tube's tamponade effect. However, due to the risk of rebleeding, imaging follow-up is necessary soon after surgery.

10.
Bioorg Med Chem ; 99: 117606, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38262304

RESUMEN

Multidrug and toxin extrusion (MATE) inhibitors improve the antimicrobial susceptibility of drug-resistant bacteria by preventing the efflux of administered antibiotics. In this study, we optimized the chemical structure of a previously identified bacterial-selective MATE inhibitor 1 (EC50 > 30 µM) to improve its activity further. Compound 1 was divided into three fragments (aromatic part, linker part, and guanidine part), and each part was individually optimized. Compound 31 (EC50 = 1.8 µM), a novel pentafluorosulfanyl-containing molecule synthesized following optimized parts, showed antimicrobial activity against MATE-expressing strains at concentrations lower than conventional inhibitor 1 when co-administrated with norfloxacin. Furthermore, 31 was not cytotoxic at effective concentrations. This suggests that compound 31 can be a promising candidate for combating bacterial infections, particularly those resistant to conventional antibiotics by MATE expression.


Asunto(s)
Antibacterianos , Proteínas de Transporte de Membrana , Proteínas de Transporte de Membrana/metabolismo , Antibacterianos/farmacología , Norfloxacino/farmacología , Transporte Biológico , Bacterias/metabolismo , Proteínas Bacterianas/metabolismo
11.
Am J Ophthalmol ; 262: 222-228, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38040322

RESUMEN

PURPOSE: To investigate the prevalence and incidence of strabismus in the Japanese population by age group and to estimate the subtype proportions. DESIGN: A nationwide population-based cohort study. METHODS: This study investigated the number of cases with previous and new diagnoses of strabismus by age group between 2009 and 2020 using the National Database of Health Insurance Claims and Specific Health Checkups of Japan, which includes almost all (≥95%) medical claims data. We calculated the strabismus prevalence and 1-year incidence in 2019 and analyzed the proportion of each strabismus subtype. RESULTS: The strabismus prevalence was 2.154% (2 709 207/125 708 000; 95% CI, 2.152%-2.157%). It showed a bimodal distribution, with a high proportion in school and old ages (especially ≥75 years). Exotropia, esotropia, and cyclovertical strabismus proportions were 67.3%, 26.0%, and 6.7%, respectively. Cyclovertical strabismus was uncommon in patients aged ≤18 years (1.4%) and more common (10.2%) in those aged >18 years. The strabismus incidence in 2019 was 321 per 100 000 person-years (403 093/125 708 000; 95% CI, 320-322). The annual incidence proportion of cyclovertical strabismus as opposed to whole strabismus subtypes in patients aged >18 years (13.1%) was higher than that in those aged ≤18 years (1.4%). CONCLUSIONS: This is the first nationwide population-based cohort study to demonstrate strabismus's overall prevalence and incidence. The high prevalence of cyclovertical strabismus in adults compared with children may suggest that cyclovertical strabismus is a primarily age-related strabismus. The high prevalence of exotropia may indicate a genetic difference between Japanese and other ethnicities.

12.
PeerJ ; 11: e16391, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025733

RESUMEN

The Sebastes inermis complex includes three sympatric species (Sebastes cheni, viz Sebastes inermis, and Sebastes ventricosus) with clear ecomorphological differences, albeit incomplete reproductive isolation. The presence of putative morphological hybrids (PMH) with plausibly higher fitness than the parent species indicates the need to confirm whether hybridization occurs within the complex. In this sense, we assessed the dynamics of genetic divergence and hybridization within the species complex using a panel of 10 microsatellite loci, and sequences of the mitochondrial control region (D-loop) and the intron-free rhodopsin (RH1) gene. The analyses revealed the presence of three distinct genetic clusters, large genetic distances using D-loop sequences, and distinctive mutations within the RH1 gene. These results are consistent with the descriptions of the three species. Two microsatellite loci had signatures of divergent selection, indicating that they are linked to genomic regions that are crucial for speciation. Furthermore, nonsynonymous mutations within the RH1 gene detected in S. cheni and "Kumano" (a PMH) suggest dissimilar adaptations related to visual perception in dim-light environments. The presence of individuals with admixed ancestry between two species confirmed hybridization. The presence of nonsynonymous mutations within the RH1 gene and the admixed ancestry of the "Kumano" morphotype highlight the potential role of hybridization in generating novelties within the species complex. We discuss possible outcomes of hybridization within the species complex, considering hybrid fitness and assortative mating. Overall, our findings indicate that the genetic divergence of each species is maintained in the presence of hybridization, as expected in a scenario of speciation-with-gene-flow.


Asunto(s)
Especiación Genética , Perciformes , Humanos , Animales , Análisis de Secuencia de ADN , Flujo Genético , Genoma
13.
Invest Ophthalmol Vis Sci ; 64(13): 24, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37847225

RESUMEN

Purpose: The purpose of this study was to explore the spatial patterns of the nonperfusion areas (NPAs) on widefield optical coherence tomography angiography (OCTA) images in diabetic retinopathy (DR) and to investigate their associations with NPA progression and DR severity. Methods: We prospectively enrolled 201 eyes from 158 patients with DR. Widefield images were obtained using a swept-source OCTA device (Xephilio OCT-S1), followed by the creation of 20-mm (1614 pixels) en face images. Nonperfusion squares (NPSs) were defined as 10 × 10-pixel squares without retinal vessels. Eyes with high-dimensional spatial data were mapped onto a two-dimensional space using the uniform manifold approximation and projection algorithm and divided by clustering. The patterns of NPA distribution were statistically compared between clusters. Results: All eyes were mapped onto a two-dimensional space and divided into six clusters based on the similarity of NPA distribution. Eyes in clusters 1 and 2 had minimal and small NPAs, respectively. Eyes in clusters 3 and 4 exhibited NPAs in the temporal and inferotemporal regions, respectively. Eyes in cluster 5 displayed NPAs in both superonasal and inferonasal areas. The unique NPA distributions in each cluster encouraged us to propose eight possible pathways of NPA progression. DR severity was not equal between clusters (P < 0.001), for example, 8 (15.7%) of 51 eyes and 15 (65.2%) of 23 eyes had PDR in clusters 1 and 5, respectively. Conclusions: Dimensionality reduction and subsequent clustering based on the NPA distribution on widefield OCTA enabled the inference of possible NPA progression in DR.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Angiografía con Fluoresceína/métodos , Tomografía de Coherencia Óptica/métodos , Vasos Retinianos , Fondo de Ojo , Estudios Retrospectivos
14.
Sci Rep ; 13(1): 17884, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37857682

RESUMEN

Morphological changes in capillaries are one of major clinical signs in diabetic retinopathy (DR). In this study, we quantified the dilated deep capillaries on optical coherence tomography angiography (OCTA) images. Central 3 × 3 mm en face images were obtained using a swept source OCTA device in 105 eyes of 99 patients with DR. Capillaries with a greater diameter in the deep layers were defined as the dilated deep capillaries, using stepwise image processing. The relative areas of automatically selected capillaries with a great diameter were calculated as the index of the dilated deep capillaries. Most eyes with DR had string-like or dot-like dilated deep capillaries in the OCTA images, which appeared to be dilated capillary segments or microaneurysms histologically. They were distributed more densely in the parafovea than in the central sector, while there were no differences between individual quadrants. The index of the dilated deep capillaries was higher in eyes with DR than in nondiabetic eyes. The index in the central subfield was modestly associated with visual acuity, diabetic macular edema, and proliferative diabetic retinopathy. The quantitative dilated deep capillaries are designated as a biomarker of vision-threatening DR.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Retinopatía Diabética/diagnóstico , Vasos Retinianos/patología , Angiografía con Fluoresceína/métodos , Capilares/patología , Tomografía de Coherencia Óptica/métodos , Edema Macular/patología , Fondo de Ojo , Estudios Retrospectivos , Diabetes Mellitus/patología
15.
Zool Stud ; 62: e21, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37408706

RESUMEN

Mothocya parvostis (Isopoda: Cymothoidae) is a parasitic crustacean that infests the opercular cavities of fishes. Its main final host is the Japanese halfbeak, Hyporhamphus sajori. However, M. parvostis also infests the black sea bream, Acanthopagrus schelgelii, as an optional intermediate host. Understanding the use of optional intermediate hosts is important for understanding the life history of Cymothoidae, and further information should be obtained. In this study, we aim to investigate the life cycle of M. parvostis. We collected and examined 20 mancae and 144 juveniles of M. parvostis from 129 cobaltcap silversides, Hypoatherina tsurugae, and 494 yellowfin seabreams, Acanthopagrus latus. Molecular analysis of the cytochrome c oxidase subunit I gene and 16S rRNA genes revealed that cymothoid mancae and juveniles from the two fish species were identified to be M. parvostis. All M. parvostis on H. tsurugae and A. latus might be mancae or juveniles, with no adult parasites; thus, H. tsurugae and A. latus juveniles were optional intermediate hosts of M. parvostis. In the results of morphological description, M. parvostis juveniles infesting the final host H. sajori lacked swimming setae, while juveniles parasitizing the two optional intermediate hosts had them. Mothocya parvostis mancae infested juveniles of both species just after metamorphosis, grew with the host. As the fish grows further, the parasite detached from the fish. The parasitic status of M. parvostis in the three optional intermediate hosts indicated that M. parvostis likely reproduced from June to December, and different optional intermediate hosts were used depending on the time of year in Hiroshima Bay. Therefore, a parasitic strategy involving optional intermediate hosts might increase the infestation success of M. parvostis to H. sajori.

16.
Zootaxa ; 5277(2): 259-286, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37518319

RESUMEN

Two species of Mothocya have previously been recorded from Hyporhamphus sajori: M. parvostis Bruce, 1986 and M. sajori Bruce, 1986. Mothocya parvostis is re-described based on the ovigerous female type and additional materials collected from the host from in and around the type locality. Morphological re-examination of fresh specimens and the type materials together with genetic data show that the M. sajori and M. parvostis are the same species, differing primarily in size, therefore we have placed Mothocya sajori Bruce, 1986 into a junior synonym of Mothocya parvostis Bruce, 1986. Mothocya parvostis is characterized by the following combinations of characters: 1) body slightly to moderately twisted to one side; 2) pereonite 7 posterior margin moderately to deeply recessed; 3) uropodal rami extending to pleotelson posterior margin; and 4) uropod rami bluntly rounded, exopod 1.5 times as long as peduncle. The differences of four morphological features for M. parvostis and M. sajori was quantified. Furthermore, a total of 635 isopods infesting H. sajori were collected from all over Japan to conduct quantitative morphological and molecular sequence analyses (mitochondrial cytochrome c oxidase subunit I and 16S rRNA). Although the four quantitative features did not overlap between the two species in type specimens, all quantitative morphological values of newly collected specimens in this study did not display a bimodal distribution. In addition, our molecular analyses found only a single clade for our newly collected specimens in neighbor-joining tree.


Asunto(s)
Beloniformes , Isópodos , Animales , Beloniformes/parasitología , Isópodos/anatomía & histología , Isópodos/genética , Parásitos/genética , ARN Ribosómico 16S , Japón , Filogenia , Filogeografía
17.
Medicina (Kaunas) ; 59(5)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37241128

RESUMEN

Diabetic retinopathy is a form of diabetic microangiopathy, and vascular hyperpermeability in the macula leads to retinal thickening and concomitant reduction of visual acuity in diabetic macular edema (DME). In this review, we discuss multimodal fundus imaging, comparing the pathogenesis and interventions. Clinicians diagnose DME using two major criteria, clinically significant macular edema by fundus examination and center-involving diabetic macular edema using optical coherence tomography (OCT), to determine the appropriate treatment. In addition to fundus photography, fluorescein angiography (FA) is a classical modality to evaluate morphological and functional changes in retinal capillaries, e.g., microaneurysms, capillary nonperfusion, and fluorescein leakage. Recently, optical coherence tomography angiography (OCTA) has allowed us to evaluate the three-dimensional structure of the retinal vasculature and newly demonstrated that lamellar capillary nonperfusion in the deep layer is associated with retinal edema. The clinical application of OCT has accelerated our understanding of various neuronal damages in DME. Retinal thickness measured by OCT enables us to quantitatively assess therapeutic effects. Sectional OCT images depict the deformation of neural tissues, e.g., cystoid macular edema, serous retinal detachment, and sponge-like retinal swelling. The disorganization of retinal inner layers (DRIL) and foveal photoreceptor damage, biomarkers of neurodegeneration, are associated with visual impairment. Fundus autofluorescence derives from the retinal pigment epithelium (RPE) and its qualitative and quantitative changes suggest that the RPE damage contributes to the neuronal changes in DME. These clinical findings on multimodal imaging help to elucidate the pathology in the neurovascular units and lead to the next generation of clinical and translational research in DME.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Edema Macular/diagnóstico por imagen , Edema Macular/etiología , Retinopatía Diabética/diagnóstico por imagen , Estudios Retrospectivos , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Imagen Multimodal/efectos adversos , Diabetes Mellitus/patología
18.
Chem Rec ; 23(9): e202300029, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37017496

RESUMEN

In recent years, hydrofluorocarbon compounds such as chlorofluorocarbons, hydrochlorofluorocarbons, and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) have been used as fluorine-containing building blocks to construct functional fluorine-containing compounds, e. g., polymers, liquid crystals, and medicines. Hydrofluorocarbons promote the formation of reactive fluoroalkyl or fluoroalkenyl species via anionic or radical processes, and these species can act as nucleophiles or electrophiles depending on the reaction conditions. Progress in fluorine chemistry using hydrofluorocarbons in the last 30 years is described in this review and diverse reactions are discussed, including the fluoroalkyl/alkenyl products and proposed mechanisms involved.

19.
J Am Chem Soc ; 145(16): 9326-9333, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37055373

RESUMEN

We report that the dearomative [4 + 2] cycloaddition between 1,2-dihydro-1,2,4,5-tetrazine-3,6-diones (TETRADs) and benzenes, naphthalenes, or N-heteroaromatic compounds under visible light irradiation affords the corresponding isolable cycloadducts. Several synthetic transformations including transition-metal-catalyzed allylic substitution reactions using the isolated cycloadducts at room temperature or above were demonstrated. Computational studies revealed that the retro-cycloaddition of the benzene-TETRAD adduct proceeds via an asynchronous concerted mechanism, while that of the benzene-MTAD adduct (MTAD = 4-methyl-1,2,4-triazoline-3,5-dione) proceeds via a synchronous mechanism.

20.
Int J Parasitol Parasites Wildl ; 20: 12-19, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36590028

RESUMEN

Cymothoid parasitic isopods infest a wide range of fish of different taxa living in marine, brackish, and freshwater environments. Most research on the reproductive season of Cymothoidae has been done by collecting or monitoring host fish afflicted with cymothoid parasites. However, collecting ecological data on cymothoid species that infest non-commercial or endangered fishes is complex and challenging. We used a quatrefoil light trap to investigate the seasonal change in species composition of cymothoid free-swimming stages in the Seto Inland Sea, Japan. We also collected preliminary data for efficient light-trap sampling and showed its effectiveness in cymothoid-related research. From October 2020 to December 2021, 613 cymothoid free-swimming stages were sampled monthly. All obtained individuals were identified as Mothocya parvostis (596), Ceratothoa verrucosa (12), and Ceratothoa carinata (5) by DNA barcoding using cytochrome c oxidase subunit I and 16S rRNA gene sequences. Based on the number of M. parvostis mancae collected each month, M. parvostis was anticipated to reproduce from June to December, with two reproduction peaks each year, and C. verrucosa and C. carinata were expected to reproduce in June, July, and September, and September and October, respectively. In addition, free-swimming juveniles were captured, presumably after they had left their optional intermediate hosts. Furthermore, the most effective time to harvest cymothoids with light traps may be during high tide on the night of the new moon. This study serves as a methodological framework for future research on cymothoids using light traps.

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