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1.
J Org Chem ; 89(13): 9473-9487, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38889001

RESUMO

We report a simple and atom-efficient method for the synthesis of bithiophene-fused isoquinolines by iridium-catalyzed [2 + 2 + 2] cycloaddition of bithiophene-linked diynes with nitriles. All three structural isomers of bithiophene-linked diynes underwent [2 + 2 + 2] cycloaddition, and the trend in the reactivity for cycloaddition was diyne 1 = diyne 3 > diyne 2. Dibenzothiophene-linked diyne also reacted with nitriles to form a variety of cycloadducts. Cycloaddition of bithiophene-linked diynes with alkynes and an isocyanate formed naphthodithiophenes and a 2-pyridone derivative, respectively. Cycloadducts bearing a 2-aminopyridine moiety and benzothiophene rings showed intense fluorescence at around 530 nm and gave a fluorescence quantum yield of 0.44. Furthermore, quantum chemical calculations provided insight into the origin of the difference in reactivity of three bithiophene-linked diynes. The different reactivities of the three diynes 1-3 are believed to originate from the step where an iridacyclopentadiene reacts with a coordinated nitrile to form azairidabicyclo[3.2.0]heptatriene. HOMOs of iridacyclopentadiene play a decisive role in this step.

2.
Front Vet Sci ; 10: 1279776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954669

RESUMO

Introduction: This study aimed to describe the technique for the surgical repair of perineal hernia (PH) in dogs using a polypropylene mesh (PM) and to evaluate its outcomes. Methods: All dogs were placed in the Trendelenburg position. Castration and caudal celiotomy for cystopexy and colopexy were performed as needed. Ipsilateral perianal incision was performed in the affected hernia side. A PM was formed a cone-shape with suturing and placed in hernial foramen. The PH was repaired with suturing between PH and pelvic diaphragm including the sacrotuberous ligament, internal obturator muscle, and external anal sphincter muscle. The medical records of all dogs were reviewed to evaluate signalment, perioperative findings, postoperative complications, and prognosis. Results: Of the 22 dogs, 15 were intact, and 7 were previously neutered. The median age and body weight were 10 years and 6.8 kg, respectively. The PH reconstruction using a cone-shaped PM was feasible in all dogs. The median operative time was 60.5 min for unilateral PH and 109 min for bilateral PH. Major postoperative complications occurred in seven dogs (32%), and three dogs (14%) had a recurrence of PH. In the long-term (> 2 weeks) follow-up period, 16 dogs (73%) had an excellent prognosis. Discussion: Our study suggests that PH reconstruction surgery using a cone-shaped PM may be a viable treatment method for PH in dogs. Therefore, a cone-shaped PM could serve as an alternative treatment option for canine PH reconstruction.

3.
J Phys Chem A ; 127(30): 6204-6212, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37433226

RESUMO

Two-photon absorption for diphenylacetylene (DPA) derivatives with two substituents (-OMe and/or -NO2) at the 4,4'-position was investigated experimentally and theoretically. The two-photon absorption spectra and the two-photon absorption cross-sections σ(2) for DPA derivatives were obtained by optical-probing photoacoustic spectroscopy (OPPAS). The simulated two-photon absorption spectra of the DPA derivatives, obtained with the time-dependent density functional theory within the Tamm-Dancoff approximation, agreed well with the experimental ones. The mechanisms for enhancement of the σ(2) for centrosymmetric and non-centrosymmetric DPA derivatives were found to be different. The large σ(2) for centrosymmetric molecules (DPA-OMeOMe and DPA-NO2NO2) results from the magnitude of the transition dipole moment, while for non-centrosymmetric molecules (DPA-OMeNO2), it is enhanced by the smaller detuning energy. Information on two-photon absorption properties of DPA derivatives obtained in this study will be important for the molecular design of two-photon absorption materials.

5.
Phys Rev Lett ; 130(17): 176701, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172230

RESUMO

We discovered a ferromagnetic Au-Ga-Dy icosahedral quasicrystal (i QC), not only with high phase purity but also with tunable composition. The isothermal magnetization of the polycrystalline ferromagnetic i QC was closely investigated and the mean-field-like nature of the ferromagnetic transition is elucidated. Moreover, the maximum Weiss temperature (θ_{p}) of the i QCs was found at the electrons-per-atom (e/a) ratio of 1.70 being well consistent with those of ACs, validating tunability of the magnetic properties of i QCs on the basis of θ_{p}-e/a scheme for the first time. Thus, the present work provided direct evidence that the magnetism of the i QCs depends on the e/a ratio or the Fermi energy, paving the way for future studies on various exotic magnetic textures formed on a quasiperiodic lattice through the e/a ratio.

6.
Vet Med Sci ; 9(3): 1078-1086, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36913113

RESUMO

BACKGROUND: Surgical resection is the treatment of choice for canine adrenal pheochromocytomas (PHEOs). Information on en bloc resection of adrenal PHEO with tumour thrombus, right hepatic division and segmental caudal vena cava (CVC) running through the adrenal tumour and right hepatic division is limited. OBJECTIVE: To describe the preemptively planned en bloc resection of an extensive right adrenal PHEO involving the right hepatic division, the caval thrombus and the segmental CVC in a dog with Budd-Chiari-like syndrome (BCLS). METHODS: A 13-year-old castrated male miniature dachshund was referred for surgical treatment due to anorexia, lethargy and severe abdominal distension caused by abundant ascites. Preoperative computed tomography (CT) revealed a large mass in the right adrenal gland with a large caval thrombus obstructing the CVC and hepatic veins, which caused BCLS. Additionally, collateral vessels were formed between the CVC and azygos veins. No findings suggested obvious metastases. Based on CT findings, an en bloc resection of the adrenal tumour with caval thrombus, right hepatic division and segmental CVC was planned. RESULTS: The preoperatively planned resection was feasible; the tumour was completely resected grossly. The operation time and total Pringle manoeuvre time were 162 min and 16 min 56 s, respectively. There was no postoperative hindlimb oedema, renal dysfunction, ascites or abdominal distention. The patient's clinical signs, including appetite, fully improved. Hospitalization lasted 16 days. However, the patient died on the 130th postoperative day due to suspected metastases and cachexia. CONCLUSIONS: Even in case of an extensive infiltration of adrenal PHEO causing BCLS, an en bloc resection might be successfully achieved based on the preoperative CT findings speculating the collateral vessels formed for caudal venous return.


Assuntos
Neoplasias das Glândulas Suprarrenais , Doenças do Cão , Feocromocitoma , Trombose , Cães , Animais , Masculino , Feocromocitoma/cirurgia , Feocromocitoma/veterinária , Feocromocitoma/patologia , Ascite/veterinária , Veia Cava Inferior/cirurgia , Veia Cava Inferior/patologia , Trombose/patologia , Trombose/veterinária , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/veterinária , Neoplasias das Glândulas Suprarrenais/patologia , Doenças do Cão/cirurgia , Doenças do Cão/patologia
7.
STAR Protoc ; 4(1): 102087, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36853691

RESUMO

Here, we present a protocol for harnessing the natural transformability of the edible algae Arthrospira platensis (common name: spirulina) to generate strains that express heterologous proteins. We describe the preparation of plasmids and the steps to grow A. platensis. We then detail the transformation and passage of the strains, followed by genomic DNA extraction and genotyping to assess integration of the gene of interest. This simple transformation protocol can be applied to genome manipulation of edible algae. For complete details on the use and execution of this protocol, please refer to Jester et al. (2022).1.


Assuntos
Spirulina , Spirulina/genética , Spirulina/metabolismo , Proteínas/metabolismo , Plasmídeos/genética
8.
J Org Chem ; 88(3): 1545-1559, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36637330

RESUMO

We report the iridium-catalyzed branch-selective hydroalkylation of simple alkenes such as aliphatic alkenes and aromatic alkenes with malonic amides and malonic esters under neutral reaction conditions. A variety of aliphatic alkenes and aromatic alkenes bearing bromine, chlorine, ester, 2-thienylcarboxylate, silyl, and phthalimide groups were all found to be suitable for this hydroalkylation. The combination of this method with Krapcho dealkoxycarbonylation realized a one-pot synthesis of ß-substituted amide and ester from ß-amide ester and malonic ester. The hydroalkylated products derived from malonic amides are suitable for further transformation. The finely tuned reaction conditions realized the selective transformation of hydroalkylated products to 1,3-diamines or monoamides with the same reagent. Deuterium labeling experiments and measurement of the kinetic isotope effect indicated that the catalytic cycle involves a reversible step and cleavage of the C-H bond is not a rate-determining step. Density functional theory calculations provided insight into the reaction mechanism, where the carboiridation step is followed by C-H reductive elimination.

9.
Org Biomol Chem ; 21(2): 323-331, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36530147

RESUMO

We report a method for the synthesis of azafluoranthenes under neutral reaction conditions in a highly atom-economical manner by the iridium-catalyzed [2 + 2 + 2] cycloaddition of 1,8-dialkynylnaphthalenes with nitriles. A variety of nitriles react with methyl- or phenyl-substituted 1,8-dialkynylnaphthalenes to give a wide range of azafluoranthenes. Azafluoranthenes bearing an amino group show intense fluorescence at around 500 nm. Comparison of the fluorescence properties of amine-substituted azafluoranthenes with related compounds revealed the importance of the amine moiety for obtaining a high fluorescence quantum yield. The choice of the solvent affected the emission maxima and the fluorescence quantum yield. Azafluoranthenes bearing pyrrolidine exhibited blue-shifted emission bands in a non-polar solvent and gave a fluorescence quantum yield of 0.76 in toluene. A Lippert-Mataga plot and computational studies provide insight into the origin of the fluorescence of azafluoranthenes. Furthermore, cellular experiments using human breast adenocarcinoma cells SK-BR-3 demonstrated the feasibility of using azafluoranthenes as fluorescent probes.


Assuntos
Irídio , Nitrilas , Humanos , Reação de Cicloadição , Solventes , Aminas , Catálise
11.
Nat Biotechnol ; 40(6): 956-964, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35314813

RESUMO

The use of the edible photosynthetic cyanobacterium Arthrospira platensis (spirulina) as a biomanufacturing platform has been limited by a lack of genetic tools. Here we report genetic engineering methods for stable, high-level expression of bioactive proteins in spirulina, including large-scale, indoor cultivation and downstream processing methods. Following targeted integration of exogenous genes into the spirulina chromosome (chr), encoded protein biopharmaceuticals can represent as much as 15% of total biomass, require no purification before oral delivery and are stable without refrigeration and protected during gastric transit when encapsulated within dry spirulina. Oral delivery of a spirulina-expressed antibody targeting campylobacter-a major cause of infant mortality in the developing world-prevents disease in mice, and a phase 1 clinical trial demonstrated safety for human administration. Spirulina provides an advantageous system for the manufacture of orally delivered therapeutic proteins by combining the safety of a food-based production host with the accessible genetic manipulation and high productivity of microbial platforms.


Assuntos
Spirulina , Animais , Biomassa , Humanos , Camundongos , Fotossíntese , Proteínas/metabolismo , Spirulina/genética , Spirulina/metabolismo
12.
Sci Rep ; 11(1): 22496, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795292

RESUMO

The effects of the size and position of an aluminum bipolar electrode (BPE) on the uniformity of formation of anodic porous alumina in an alternating current electric field were investigated. Anodized specimens were dyed, and the resistance was measured after the specimens were anodized again. Phenomena observed during film formation indicated that the BPEs had unique potential distributions that strongly depended on their length and width. The color variations and electrical resistance of the BPEs were symmetrical and varied from the centers of the BPEs to their ends. When multiple BPEs were processed at the same time, their position in the non-uniform electric field was demonstrated to be an important factor for controlling the uniformity of film formation. The best results were obtained when the BPE was placed at the center of the defined space.

13.
Chem Commun (Camb) ; 57(76): 9684-9687, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34555140

RESUMO

The development of efficient synthetic methods of 7-azaindoles has been desired due to the useful biological activities and physical properties. We report the first example of the iridium-catalyzed C3-selective asymmetric allylation of 7-azaindoles with racemic secondary allylic alcohols to give only branched allylation products in good to high yields with high enantioselectivity (up to >99.5% ee). Allylic alcohols and 7-azaindoles with a variety of functional groups including halogen and heteroaromatic groups are compatible with the reaction conditions. Furthermore, transformations of the obtained allylation products are demonstrated without a significant loss of enantiomeric excess.

14.
J Vet Med Sci ; 83(11): 1740-1744, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34544935

RESUMO

Canine gastroesophageal intussusception (GEI) is a rare and life-threatening condition that requires prompt diagnosis and treatment. A 19-day-old Siberian Husky with a 4-day history of regurgitation was diagnosed with GEI based on the findings of computed tomography (CT) performed without anesthesia. Endoscopic reduction of intussusception was impossible; thus, surgical reduction by traction of the duodenum was performed. CT revealed improvement of megaesophagus 82 days postoperatively. Eleven months postoperatively, fluoroscopy showed recovery to nearly normal esophageal motility. Two years postoperatively, no clinical signs were reported. CT is useful to diagnose GEI in neonate puppies with poor abdominal fat and to assess the gastric edema and the anatomical association of stomach with other organs. Fluoroscopy is helpful for evaluating postoperative esophageal motility.


Assuntos
Doenças do Cão , Acalasia Esofágica , Doenças do Esôfago , Intussuscepção , Gastropatias , Animais , Doenças do Cão/cirurgia , Cães , Acalasia Esofágica/cirurgia , Acalasia Esofágica/veterinária , Doenças do Esôfago/veterinária , Intussuscepção/cirurgia , Intussuscepção/veterinária , Gastropatias/veterinária
15.
Nat Commun ; 12(1): 4219, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244505

RESUMO

Streptococcus pyogenes (Spy) Cas9 has potential as a component of gene therapeutics for incurable diseases. One of its limitations is its large size, which impedes its formulation and delivery in therapeutic applications. Smaller Cas9s are an alternative, but lack robust activity or specificity and frequently recognize longer PAMs. Here, we investigated four uncharacterized, smaller Cas9s and found three employing a "GG" dinucleotide PAM similar to SpyCas9. Protein engineering generated synthetic RNA-guided nucleases (sRGNs) with editing efficiencies and specificities exceeding even SpyCas9 in vitro and in human cell lines on disease-relevant targets. sRGN mRNA lipid nanoparticles displayed manufacturing advantages and high in vivo editing efficiency in the mouse liver. Finally, sRGNs, but not SpyCas9, could be packaged into all-in-one AAV particles with a gRNA and effected robust in vivo editing of non-human primate (NHP) retina photoreceptors. Human gene therapy efforts are expected to benefit from these improved alternatives to existing CRISPR nucleases.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Staphylococcus/enzimologia , Animais , Proteína 9 Associada à CRISPR/isolamento & purificação , Linhagem Celular Tumoral , Dependovirus , Modelos Animais de Doenças , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Células HEK293 , Humanos , Macaca fascicularis , Masculino , Camundongos , Parvovirinae/genética , Engenharia de Proteínas , Ribonucleases , Staphylococcus/genética , Especificidade por Substrato , Síndromes de Usher/genética , Síndromes de Usher/terapia , RNA Guia de Sistemas CRISPR-Cas
16.
J Phys Chem A ; 125(8): 1688-1695, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33600722

RESUMO

Two-photon absorption for diphenylacetylene derivatives with an electron-donating (ED) or electron-withdrawing (EW) group (DPA-Rs) was investigated by high-sensitivity optical-probing photoacoustic spectroscopy. Two-photon absorption spectra and two-photon absorption cross sections σ(2) for DPA-Rs were successfully obtained. Two-photon absorption spectra of DPA-Rs with stronger ED or EW groups display more significant red-shifts and larger σ(2) values. Simulated two-photon absorption spectra, using time-dependent density functional theory within the Tamm-Dancoff approximation, compared well with the experimental spectra. Based on the three-state model, the substituent effect on the two-photon absorption for DPA-Rs was expected to manifest in the transition dipole moments and detuning energies. Information obtained from investigating the monosubstituent effect on two-photon absorption of DPA is critical for an improved understanding of two-photon absorption.

17.
Org Lett ; 22(15): 6187-6191, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32697586

RESUMO

Transition-metal-catalyzed hydroalkylation of alkenes with 1,3-dicarbonyl compounds is a useful reaction to construct a C-C bond under neutral reaction conditions in a highly atom-economical manner. We found that hydroalkylation of aliphatic alkenes with ß-ketoesters proceeded with the use of a cationic iridium complex and bidentate phosphine ligand to give selectively branched α-substituted ß-ketoesters in high yields. The obtained hydroalkylated compounds can be converted to ß-substituted ketones through one-pot Krapcho dealkoxycarbonylation.

18.
J Chem Phys ; 151(13): 134304, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31594351

RESUMO

Two-photon absorption spectra and two-photon absorption cross sections of Cl-substituted diphenylacetylenes (ClDPAs) were investigated by optical-probing photoacoustic spectroscopy and quantum chemical calculations for the first time. The two-photon absorption spectra of ClDPAs exhibited intense two-photon absorption bands at around 480 nm, which are forbidden by one-photon absorption. The two-photon absorption cross sections σ(2) of o-, m-, and p-ClDPAs at 476 nm were determined to be 22 ± 1, 23 ± 1, and 38 ± 2 GM, respectively. Compared with diphenylacetylene (DPA) (27 GM at 472 nm), the σ(2) values of o- and m-ClDPAs were lower, while that of p-ClDPA was higher. Simulated two-photon absorption spectra using the TD-B3LYP/6-311+G(d,p) level of calculations within the Tamm-Dancoff approximation, based on the three-state model, well agreed with the experimental results. The difference in the σ(2) values of DPA and ClDPAs was responsible for those in the transition dipole moments between the intermediate and the final states.

20.
Org Lett ; 21(3): 741-744, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30638390

RESUMO

Intermolecular hydroalkylation of unactivated terminal alkenes with 1,3-diketones under neutral conditions has been achieved using a cationic iridium catalyst. An active C-H bond of 2,4-pentadione (2a) added to 1-octene (1a) under refluxing DCE to give a Markovnikov product in 88% yield. A broad scope of alkenes and 1,3-diketones was observed. The products were easily converted to heterocycles. This reaction provides a new method for extending a carbon chain from an unactivated aliphatic terminal alkene.

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