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1.
Nature ; 554(7693): 511-514, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29469096

RESUMO

Aryl fluorides are widely used in the pharmaceutical and agrochemical industries, and recent advances have enabled their synthesis through the conversion of various functional groups. However, there is a lack of general methods for direct aromatic carbon-hydrogen (C-H) fluorination. Conventional methods require the use of either strong fluorinating reagents, which are often unselective and difficult to handle, such as elemental fluorine, or less reactive reagents that attack only the most activated arenes, which reduces the substrate scope. A method for the direct fluorination of aromatic C-H bonds could facilitate access to fluorinated derivatives of functional molecules that would otherwise be difficult to produce. For example, drug candidates with improved properties, such as increased metabolic stability or better blood-brain-barrier penetration, may become available. Here we describe an approach to catalysis and the resulting development of an undirected, palladium-catalysed method for aromatic C-H fluorination using mild electrophilic fluorinating reagents. The reaction involves a mode of catalysis that is unusual in aromatic C-H functionalization because no organometallic intermediate is formed; instead, a reactive transition-metal-fluoride electrophile is generated catalytically for the fluorination of arenes that do not otherwise react with mild fluorinating reagents. The scope and functional-group tolerance of this reaction could provide access to functional fluorinated molecules in pharmaceutical and agrochemical development that would otherwise not be readily accessible.


Assuntos
Carbono/química , Flúor/química , Halogenação , Hidrogênio/química , Paládio/química , Barreira Hematoencefálica , Catálise , Indicadores e Reagentes/química , Preparações Farmacêuticas/química
2.
Dig Endosc ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695106

RESUMO

OBJECTIVES: Bleeding after endoscopic submucosal dissection (ESD) for gastric tumors in patients taking antithrombotic drugs, in particular direct oral anticoagulants (DOACs), remains unresolved; therefore, we evaluated the risk factors for post-ESD bleeding and drug differences in patients taking DOACs. METHODS: We included 278 patients taking antithrombotic drugs who underwent gastric ESD between January 2017 and March 2022. Antithrombotic drugs were withdrawn following the 2017 guidelines (Appendix on anticoagulants including DOACs). To further clarify differences in antithrombotic agents' effects, the peri-cancerous mucosa in the resected specimen was pathologically evaluated according to the Updated Sydney System. Multivariate analysis was performed to assess the risk of post-ESD bleeding. RESULTS: The incidence of post-ESD bleeding in patients taking DOACs was 19.6% (10/51). Among patients taking antithrombotic drugs, DOACs were identified as a possible factor involved in post-ESD bleeding (odds ratio [OR] 4.92). Among patients taking DOACs, possible factors included resection length diameter ≥30 mm (OR 3.72), presence of neutrophil infiltration (OR 2.71), lesions occurring in the lower third of stomach (OR 2.34), and preoperative antiplatelet use (OR 2.22). Post-ESD bleeding by DOAC type was 25.0% of patients (4/16) receiving apixaban, in 20.0% (3/15) receiving edoxaban, in 21.4% (3/14) receiving rivaroxaban, and in none of those receiving dabigatran. CONCLUSIONS: The administration of DOACs was shown to be a possible factor involved in post-ESD bleeding, and risk factors for patients taking DOACs included neutrophil infiltration. The pharmacological differences in the effects of DOACs contributing to bleeding in gastric ulcers suggest comparatively less bleeding with dabigatran after ESD.

3.
BMC Nurs ; 23(1): 248, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38627792

RESUMO

BACKGROUND: The nursing shortage represents a persistent and urgent challenge within the healthcare industry. One of the most cost-effective and time-efficient solutions to address this issue is the recruitment of inactive nurses to rejoin the nursing workforce, while simultaneously ensuring the long-term sustainability of their careers following their return to work. The aim of this study is to explore the factors that facilitate the retention of nurses who have returned to work, from their perspective. METHODS: To achieve this aim, a qualitative descriptive design was employed. A total of 15 registered nurses who had not practiced nursing for a minimum of three years prior to their return to work, and had been working as nurses for at least three months following their return, were selected from seven healthcare institutions using convenience sampling. Face-to-face or online semi-structured interviews were conducted, and qualitative inductive analysis was employed to analyze the collected data. RESULTS: The analysis revealed five key themes, two of which were related to the enabling factors making it possible for the nurses to continue their work, while the remaining three pertained to the motivating factors driving the pursuit of professional careers. The two themes associated with enabling factors were identified as "Conditions and support that sustain work-life balance" and "A workplace that acknowledges my career, and encourages my growth as an experienced nurse". The three themes related to motivating factors were entitled "Pride in reconnecting with and contributing to society," "Cultivating confidence through incremental professional development and future envisioning," and "Enrichment of my own and my family's life". CONCLUSIONS: Returning nurses constitute a valuable asset for healthcare institutions. To effectively retain these nurses, it is crucial to implement multi-dimensional approaches that enable and motivate them to sustain and enrich their professional and personal lives while continuing their work in the nursing field.

4.
Anal Chem ; 95(8): 3940-3950, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36725678

RESUMO

Extracellular acidification indicates a metabolic shift in cancer cells and is, along with tissue hypoxia, a hallmark of tumor malignancy. Thus, non-invasive mapping of extracellular pH (pHe) is essential for researchers to understand the tumor microenvironment and to monitor tumor response to metabolism-targeting drugs. While electron paramagnetic resonance (EPR) has been successfully used to map pHe in mouse xenograft models, this method is not sensitive enough to map pHe with a moderate amount of exogenous pH-sensitive probes. Here, we show that a modified EPR system achieves twofold higher sensitivity by using the multiple harmonic detection (MHD) method and improves the robustness of pHe mapping in mouse xenograft models. Our results demonstrate that treatment of a mouse xenograft model of human-derived pancreatic ductal adenocarcinoma cells with the carbonic anhydrase IX (CAIX) inhibitor U-104 delays tumor growth with a concurrent tendency toward further extracellular acidification. We anticipate that EPR-based pHe mapping can be expanded to monitor the response of other metabolism-targeting drugs. Furthermore, pHe monitoring can also be used for the development of improved metabolism-targeting cancer treatments.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Animais , Camundongos , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Antígenos de Neoplasias/metabolismo , Carcinoma Ductal Pancreático/patologia , Modelos Animais de Doenças , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Microambiente Tumoral
5.
Scand J Gastroenterol ; 57(4): 449-456, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34978242

RESUMO

BACKGROUND: Dasatinib, a second-generation tyrosine kinase inhibitor, is widely used in patients with haematological malignancies. The main side effects of dasatinib are myelosuppression and pleural effusion; however, colitis, such as haemorrhagic colitis and cytomegalovirus (CMV) colitis, have been reported as rare side effects. There are only a few studies conducted on dasatinib-induced colitis. AIMS: This study aimed to clarify the clinical, endoscopic and pathological features of dasatinib-induced colitis. METHODS: This retrospective study included 51 consecutive patients who received dasatinib therapy between June 2009 and July 2020. Dasatinib-induced colitis was defined as the presence of colitis symptoms, exclusion of other diseases that could cause colitis, and improvement in symptoms after dasatinib withdrawal or dose reduction. CMV positivity was determined based on the positive result of CMV immunostaining. RESULTS: Dasatinib-induced colitis was diagnosed in nine of 51 patients (17.6%), and most of the symptoms were mild diarrhoea and bloody stools. The endoscopic findings were characterised by loss of vascular pattern (100%) and multiple small erosions (83.3%) which were mainly found in the transverse and descending colon. In a patient who underwent follow-up colonoscopy once a year while taking dasatinib, endoscopic findings changed from initial erythematous spots to multiple erosions, and finally to multiple small round elevations with erosion on the top that disappeared after discontinuation of dasatinib. Anti-CMV therapy was administered to one patient, but the treatment failed. All patients with dasatinib-induced colitis were cured after the discontinuation of dasatinib. CONCLUSION: Physicians should consider CMV reactivation to manage dasatinib-induced colitis.


Assuntos
Colite , Infecções por Citomegalovirus , Enterocolite , Colite/diagnóstico , Colonoscopia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/tratamento farmacológico , Dasatinibe/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Humanos , Estudos Retrospectivos
6.
Biochem Biophys Res Commun ; 522(1): 144-150, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31757415

RESUMO

Mitochondrial dynamics are crucial for cellular survival in response to various stresses. Previously, we reported that Drp1 promoted mitochondrial fission after x-irradiation and its inhibition resulted in reduced cellular radiosensitivity and mitotic catastrophe. However, the mechanisms of radiation-induced mitotic catastrophe related to mitochondrial fission remain unclear. In this study, we investigated the involvement of cellular ATP production, ROS generation, and Ca2+ levels in mitotic catastrophe in EMT6 cells. Knockdown of Drp1 and Fis1, which are mitochondrial fission regulators, resulted in elongated mitochondria and significantly attenuated cellular radiosensitivity. Reduced mitochondrial fission mainly decreased mitotic catastrophe rather than necrosis and apoptosis after irradiation. Cellular ATP contents in Drp1 and Fis1 knockdown cells were similar to those in control cells. N-acetylcysteine and 2-glucopyranoside ascorbic acid have no effect on mitotic catastrophe after irradiation. The cellular [Ca2+]i level increased after irradiation, which was completely suppressed by Drp1 and Fis1 inhibition. Furthermore, BAPTA-AM significantly reduced radiation-induced mitotic catastrophe, indicating that cellular Ca2+ is a key mediator of mitotic catastrophe induction after irradiation. These results suggest that mitochondrial fission is associated with radiation-induced mitotic catastrophe via cytosolic Ca2+ regulation.


Assuntos
Neoplasias da Mama/metabolismo , Cálcio/metabolismo , Dinâmica Mitocondrial , Trifosfato de Adenosina/metabolismo , Animais , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Linhagem Celular Tumoral , Feminino , Camundongos , Dinâmica Mitocondrial/efeitos da radiação , Mitose/efeitos da radiação , Tolerância a Radiação , Espécies Reativas de Oxigênio/metabolismo , Raios X
7.
J Clin Biochem Nutr ; 67(3): 240-247, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33293764

RESUMO

Mitotic catastrophe is a form of cell death linked to aberrant mitosis caused by improper or uncoordinated mitotic progression. Abnormal centrosome amplification and mitotic catastrophe occur simultaneously, and some cells with amplified centrosomes enter aberrant mitosis, but it is not clear whether abnormal centrosome amplification triggers mitotic catastrophe. Here, to investigate whether radiation-induced abnormal centrosome amplification is essential for induction of radiation-induced mitotic catastrophe, centrinone-B, a highly selective inhibitor of polo-like kinase 4, was utilized to inhibit centrosome amplification, since polo-like kinase 4 is an essential kinase in centrosome duplication. When human cervical tumor HeLa cells and murine mammary tumor EMT6 cells were irradiated with 2.5 Gy of X-rays, cells with morphological features of mitotic catastrophe and the number of cells having >2 centrosomes increased in both cell lines. Although centrinone-B significantly inhibited radiation-induced abnormal centrosome amplification in both cell lines, such treatment did not change cell growth and significantly enhanced mitotic catastrophe in HeLa cells exposed to X-rays. In contrast, inhibition of centrosome amplification reduced cell growth and mitotic catastrophe in EMT6 cells exposed to X-rays. These results indicated that the role of radiation-induced abnormal centrosome amplification in radiation-induced mitotic catastrophe changes, depending on the cell type.

8.
Nihon Shokakibyo Gakkai Zasshi ; 117(11): 971-977, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33177259

RESUMO

A 67-year-old man was diagnosed with ulcerative colitis one year ago. Remission was induced via the oral administration of prednisolone and azathioprine;prednisolone was gradually reduced and discontinued. He maintained remission with azathioprine but developed fever and general malaise and visited the Kagawa Prefectural Central Hospital. Chest radiography and a urinary antigen test revealed Legionella pneumonia. His symptoms reduced immediately after the initiation of levofloxacin. Azathioprine suppresses cellular immunity and may increase the risk of Legionella pneumonia.


Assuntos
Colite Ulcerativa , Legionella , Pneumonia , Idoso , Azatioprina/efeitos adversos , Colite Ulcerativa/tratamento farmacológico , Humanos , Imunossupressores/efeitos adversos , Masculino
9.
Anal Chem ; 90(23): 13938-13945, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30372035

RESUMO

An electron paramagnetic resonance (EPR)-based method for noninvasive three-dimensional extracellular pH mapping was developed using a pH-sensitive nitroxyl radical as an exogenous paramagnetic probe. Fast projection scanning with a constant magnetic field sweep enabled the acquisition of four-dimensional (3D spatial +1D spectral) EPR images within 7.5 min. Three-dimensional maps of pH were reconstructed by processing the pH-dependent spectral information on the images. To demonstrate the proposed method of pH mapping, the progress of extracellular acidosis in tumor-bearing mouse legs was studied. Furthermore, extracellular pH mapping was used to visualize the spatial distribution of acidification in different tumor xenograft mouse models of human-derived pancreatic ductal adenocarcinoma cells. The proposed EPR-based pH mapping method enabled quantitative visualization of regional changes in extracellular pH associated with altered tumor metabolism.


Assuntos
Carcinoma Ductal Pancreático/patologia , Carcinoma de Células Escamosas/patologia , Imageamento Tridimensional , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Neoplasias Experimentais/patologia
10.
Biochem Biophys Res Commun ; 495(2): 1601-1607, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29217195

RESUMO

Mitochondrial dynamics are suggested to be indispensable for the maintenance of cellular quality and function in response to various stresses. While ionizing radiation (IR) stimulates mitochondrial fission, which is mediated by the mitochondrial fission protein, dynamin-related protein 1 (Drp1), it remains unclear how IR promotes Drp1 activation and subsequent mitochondrial fission. Therefore, we conducted this study to investigate these concerns. First, we found that X-irradiation triggered Drp1 phosphorylation at serine 616 (S616) but not at serine 637 (S637). Reconstitution analysis revealed that introduction of wild-type (WT) Drp1 recovered radiation-induced mitochondrial fission, which was absent in Drp1-deficient cells. Compared with cells transfected with WT or S637A Drp1, the change in mitochondrial shape following irradiation was mitigated in S616A Drp1-transfected cells. Furthermore, inhibition of CaMKII significantly suppressed Drp1 S616 phosphorylation and mitochondrial fission induced by IR. These results suggest that Drp1 phosphorylation at S616, but not at S637, is prerequisite for radiation-induced mitochondrial fission and that CaMKII regulates Drp1 phosphorylation at S616 following irradiation.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Dinaminas/metabolismo , Dinâmica Mitocondrial/fisiologia , Dinâmica Mitocondrial/efeitos da radiação , Substituição de Aminoácidos , Animais , Benzilaminas/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Células Cultivadas , Dinaminas/química , Dinaminas/genética , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Dinâmica Mitocondrial/efeitos dos fármacos , Mutagênese Sítio-Dirigida , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serina/química , Sulfonamidas/farmacologia , Transfecção
11.
BMC Gastroenterol ; 18(1): 46, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29631560

RESUMO

BACKGROUND: Bleeding after endoscopic submucosal dissection (ESD) in antithrombotic drug users is still one of the important issues to be solved. We performed scheduled second-look endoscopy (SLE) 5 days after ESD, when the resumption of antithrombotic agents is assumed to have achieved a steady state, rather than on the day after ESD. We investigated bleeding incidence and the status of ulcers. METHODS: A total of 299 lesions in 299 patients subjected to ESD for gastric neoplasms were enrolled. A double dose of proton pump inhibitors was administered after ESD. SLE was planned 5 days after ESD. Post-ESD bleeding occurring before SLE was defined as early phase post-ESD bleeding, whereas bleeding after SLE was defined as later phase post-ESD bleeding. Forrest IIa and IIb ulcers are defined as high-risk ulcers requiring prophylactic hemostasis. We investigated risk factors for post-ESD bleeding, particularly focusing on the use of antithrombotic agents and the presence of high-risk ulcers requiring prophylactic hemostasis during SLE. RESULTS: Under a double dose of proton pump inhibitors, early phase post-ESD bleeding occurred in 2.3% of non-users (5/218) and 6.2% of users of antithrombotic agents (5/81). High-risk ulcers were found in 19.0% of the cases during scheduled SLE (55/289). Later phase bleeding occurred in 5.5% of cases [2.8% of non-users (6/213) and 13.2% of users of antithrombotic agents (10/76)]. Cox regression analysis revealed that the risk factor for post-ESD bleeding was antithrombotic treatment (HR: 3.56; 95% CI: 1.63-8.02, p = 0.002) alone. Among patients with high-risk ulcers, a statistically significant increase in bleeding was observed in the later phase in patients under antithrombotic therapy, compared to those not receiving any antithrombotic agents (p = 0.001). CONCLUSIONS: Antithrombotic treatment is a risk factor for post-ESD bleeding despite SLE being scheduled 5 days after ESD. Later phase post-ESD bleeding was observed in 13.2% of the patients under antithrombotic treatment even after prophylactic hemostasis for high-risk ulcers. TRIAL REGISTRATION: This study was registered in the UMIN Clinical Trials Registry System ( 000023306 ). Retrospectively registered on 23rd July 2016.


Assuntos
Ressecção Endoscópica de Mucosa/efeitos adversos , Endoscopia Gastrointestinal/efeitos adversos , Hemorragia Gastrointestinal/etiologia , Hemorragia Pós-Operatória/etiologia , Neoplasias Gástricas/cirurgia , Úlcera Gástrica/complicações , Idoso , Feminino , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Inibidores da Bomba de Prótons/efeitos adversos , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos , Fatores de Risco , Cirurgia de Second-Look , Neoplasias Gástricas/complicações , Úlcera Gástrica/tratamento farmacológico , Fatores de Tempo
12.
J Am Chem Soc ; 137(49): 15418-21, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26632863

RESUMO

We report here catalytic asymmetric iterative and domino cross-aldol reactions between aldehydes, endowed with a high level of robustness, flexibility, and generality. A Cu(I)-DTBM-SEGPHOS complex catalyzes an asymmetric cross-aldol reaction between acceptor aldehydes and boron enolates derived from donor aldehydes, which are generated through Ir-catalyzed isomerization of allyloxyboronates. The unit process can be repeated using the aldol products in turn as acceptor substrates for the subsequent asymmetric aldol reaction. The donor aldehydes and stereoselectivity can be flexibly switched in a stepwise manner for the double-aldol reaction. Furthermore, asymmetric triple- and quadruple-aldol reactions are possible in one-pot using the appropriate amounts of donors and amine additives, rapidly elongating the carbon skeleton with controlling up to eight stereocenters. The method should be useful for straightforward synthesis of enantiomerically and diastereomerically enriched 1,3-polyols.

13.
Nihon Shokakibyo Gakkai Zasshi ; 111(5): 924-30, 2014 May.
Artigo em Japonês | MEDLINE | ID: mdl-24806236

RESUMO

A man in his twenties had intermittent abdominal pain in the right lower quadrant for more than 4 years. The abdominal pain persisted after a meal, and he visited our hospital emergency department. We performed an emergency colonoscopy and found a 3-cm mobile polypoid lesion located on the antimesenteric side of the ileum 40 cm from the ileocecal valve and was 85×26×23 mm in size. On the basis of characteristic ultrasound and contrast-enhanced CT findings, our preoperative diagnosis was intussusception due to Meckel's diverticulum translation and performed a laparoscopic ileocecal resection. The pathological diagnosis was Meckel's diverticulum translation with ectopic pancreatic and gastric tissue. Furthermore, we aggregated the cases of adult intussusception due to Meckel's diverticulum translation reported in Japan, and investigated preoperative diagnoses and treatment plans.


Assuntos
Colonoscopia , Intussuscepção/etiologia , Intussuscepção/patologia , Divertículo Ileal/patologia , Humanos , Masculino , Adulto Jovem
14.
Sci Rep ; 14(1): 4953, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418651

RESUMO

The objective of this study was to clarify the long-term prognosis of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma with additional copies of MALT1. In this multicenter retrospective study, we enrolled 145 patients with gastric MALT lymphoma who underwent fluorescence in situ hybridization (FISH) analysis to detect t(11;18) translocation. The patient cohort was divided into three groups: Group A (n = 87), comprising individuals devoid of the t(11;18) translocation or extra MALT1 copies; Group B (n = 27), encompassing patients characterized by the presence of the t(11;18) translocation; and Group C (n = 31), including patients with extra MALT1 copies. The clinical outcomes in each cohort were collected. Over the course of a mean follow-up of 8.5 ± 4.2 years, one patient died of progressive MALT lymphoma, while 15 patients died due to etiologies unrelated to lymphoma. The progression or relapse of MALT lymphoma was observed in 11 patients: three in Group A, two in Group B, and six in Group C. In Groups A, B, and C, the 10-year overall survival rates were 82.5%, 93.8%, and 86.4%, respectively, and the 10-year event-free survival rates were 96.1%, 96.0%, and 82.9%, respectively. The event-free survival rate in Group C was significantly lower than that in Group A. However, no differences were observed in the 10-year event-free survival rates among individuals limited to stage I or II1 disease (equivalent to excluding patients with stage IV disease in this study, as there were no patients with stage II2), with rates of 98.6%, 95.8%, and 92.3% for Groups A, B, and C, respectively. In conclusion, the presence of extra copies of MALT1 was identified as an inferior prognostic determinant of event-free survival. Consequently, trisomy/tetrasomy 18 may serve as an indicator of progression and refractoriness to therapeutic intervention in patients with gastric MALT lymphoma, particularly stage IV gastric MALT lymphoma.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Linfoma não Hodgkin , Neoplasias Gástricas , Humanos , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/patologia , Hibridização in Situ Fluorescente , Estudos Retrospectivos , Recidiva Local de Neoplasia/genética , Translocação Genética , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética
15.
Org Lett ; 25(31): 5856-5861, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37499637

RESUMO

Herein, a novel route to atropisomeric N-aryl quinolones with low rotational barriers is demonstrated, leveraging a dual photochemical/organocatalytic approach to the required ring closure in up to 94% yield and up to >99% ee. The use of a continuous flow system allows for impurity suppression and enables rapid scale-up to a decagram scale.

16.
J Food Biochem ; 46(12): e14482, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36219767

RESUMO

Aged garlic extract (AGE) has been shown to protect the skin against UV-induced damage, but effects of its volatile components remain unknown. We investigated the effects of the volatile fraction of AGE on the responses of cultured skin fibroblasts subjected to UV-B irradiation. UV-B irradiation (20 mJ/cm2 ) reduced the cell viability to 55% of control. The nonvolatile and volatile fractions of AGE inhibited the UV-B-induced reduction of cell viability; the cell viabilities were 100% and 73%, respectively. The volatile fraction inhibited the UV-B-induced increase in apoptotic cell death by 28%. The volatile fraction also inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) induced by UV-B irradiation. GC-MS analysis revealed that a large number of volatile compounds were generated during aging of garlic. These results suggest that the volatile fraction of AGE has protective effects against the UV-B-induced death of skin fibroblasts, and that this effect may partly be due to an inhibition of apoptosis via the downregulation of MAPK signaling. The volatile compounds of AGE may have beneficial applications for skin health. PRACTICAL APPLICATIONS: In this study, we investigated the effects of AGE against cell damage of UV-B-irradiated human skin fibroblasts. The aging process of garlic produced characteristic volatile compounds that have significant protective effects against UV-induced cell damage. Our results demonstrated that the aging process is a suitable method to develop added value in garlic extracts to improve skin health.


Assuntos
Alho , Humanos , Idoso , Pele , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Antioxidantes/farmacologia , Fibroblastos , Apoptose , Raios Ultravioleta/efeitos adversos
17.
J Am Chem Soc ; 133(25): 9730-3, 2011 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-21627092

RESUMO

Despite the remarkable advances in catalytic asymmetric aziridinations over the past decades, establishing a general procedure for the stereoselective synthesis of trisubstituted aziridines has remained an elusive goal. Chiral N-triflyl phosphoramide-catalyzed reactions of N-α-diazoacyl oxazolidinones and N-Boc imines were developed as a solution to this unmet challenge.

18.
Int J Nurs Sci ; 8(1): 79-86, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33575449

RESUMO

OBJECTIVES: The aim of this study was to explore factors that motivate students to engage in skills practice in a laboratory setting, and to identify their motivation types and the regulatory styles. METHODS: Semi-structured interviews were conducted with 23 nursing students from three universities between November 2017 and January 2018. A thematic analysis was used to identify factors associated with students' motivation to engage in skills practice in a laboratory. The types and the regulatory styles of student motivation were identified based on the self-determination theory. RESULTS: Seven motivating factors were identified. These factors included the students' desire "to acquire the skills necessary to work as a nurse", the "desire to improve skills in preparation for clinical practicum", and their felt "obligations to patients as a nurse". Moreover, "the impetus to study arising from the objective evaluation of oneself and others" and "wanting to pass the skills examination" motivated the students to engage in skills practice. A "learning environment that facilitates students' learning" and the "supportive involvement of educators" facilitated their learning. Based on the self-determination theory, the students were found to embrace extrinsic motivation with four regulatory styles of motivation, namely integrated, identified, introjected, and external regulation. CONCLUSIONS: Nurse educators should understand the motivating factors of students, and help students embrace a more internally controlled motivation by helping them envision their future careers as nurses, and by fostering their ethical duty to care for patients.

19.
Mol Ther Oncolytics ; 22: 143-151, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34514095

RESUMO

Metformin has many anti-cancer effects, alone or in combination with radiation. However, the mechanism underlying its radio-sensitized effect is still unclear, especially for cancer stem-like cells (CSCs). Here, the radio-sensitized effect of metformin was investigated, and its mechanism was revealed in CSCs derived from canine osteosarcoma cell line (HMPOS), a canine osteosarcoma cell line. Spheroid cells (SCs) were used as CSCs-rich cells derived from sphere formation, and SCs were compared with normal adherent culture cells (ACs). The radio-sensitizing effect of metformin using clonogenic assay and tumor growth in mice xenograft model were evaluated, and the mechanism of its radio-sensitization focusing on mitochondrial function was revealed. Metformin significantly enhanced radio-sensitivity of SCs through its inhibition of the mitochondrial function, as shown by decreased oxygen consumption, decreased mitochondrial membrane potential, and decreased ATP production. Additionally, SCs had a higher ability of mitochondrial respiration than ACs, which may have caused difference of their sensitivity of metformin and irradiation. In conclusion, mitochondrial function might play an important role in the sensitivity of metformin and irradiation, and drugs that target mitochondrial respiration, such as metformin, are promising radio-sensitizers to target CSCs.

20.
Clin J Gastroenterol ; 13(6): 1028-1035, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32852724

RESUMO

Neuroendocrine carcinoma in Barrett's esophagus is rare and its developmental mechanisms remain unclear. Neuroendocrine carcinoma arising in Barrett's esophagus with adenocarcinoma was detected at an early stage and resected by endoscopic submucosal dissection. Detailed pathological examination revealed that the neuroendocrine carcinoma originated via differentiation of the preexisting adenocarcinoma. A 79-year-old man presented with a flat protruding lesion in the esophagogastric junction. Esophagogastroduodenoscopy revealed a red flat 10-mm protruding lesion in the Barrett's epithelium and a shallow depression at the distal end. Narrow band imaging with magnification showed that the blood vessels in the protrusion were dilated and meandered irregularly, while those in the depression were small and did not form a network; the blood vessels were missing in some parts of the depression. Well-differentiated adenocarcinoma was diagnosed after analysis of the biopsy specimen of the protrusion, and endoscopic submucosal dissection was performed. The pathological diagnosis was neuroendocrine carcinoma with an adenocarcinoma component.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Carcinoma Neuroendócrino , Neoplasias Esofágicas , Adenocarcinoma/cirurgia , Idoso , Esôfago de Barrett/complicações , Esôfago de Barrett/cirurgia , Carcinoma Neuroendócrino/complicações , Carcinoma Neuroendócrino/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Humanos , Masculino
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