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1.
Chirality ; 36(1): e23625, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37880144

RESUMEN

In the study of phthalocyanine complexes using magnetic circular dichroism (MCD) spectroscopy, the electronic structure of excited states is generally discussed based on the rigid-shift approximation, in which the band profiles for left-handed circularly polarized (lcp) and right-handed circularly polarized (rcp) light are assumed to be the same. This assumption may not necessarily be valid for cases where there are multiple initial states having different geometries. Magnetic circularly polarized luminescence (MCPL) from phthalocyanine complexes can be regarded as an example of such cases, since the two degenerate emission states are split in a magnetic field and can undergo a structural deformation. Here, we investigated an alternative approach, where the lcp and rcp components are independently determined. This method, which we refer to as the direct-separation approach, allows direct determination of the distribution of the two emission states as well as the orbital angular momentum L z $$ \left|{L}_z\right| $$ . Using this approach, L z $$ \left|{L}_z\right| $$ and the distribution were determined from MCD and MCPL spectra of a series of phthalocyanine complexes. Comparison of the two methods shows that the rigid-shift and the direct-separation approaches give practically equivalent results for the systems under study, but the latter is advantageous for systems where the former is not applicable.

2.
Chirality ; 36(2): e23648, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38384149

RESUMEN

Magnetic circular dichroism (MCD) spectroscopy is a powerful method for evaluating the electronic structure and magnetic and optical properties of molecules. In particular, MCD measurements have been performed on phthalocyanines and porphyrins with various central metal ions, axial ligands, and substituents to elucidate their properties. It is essential to develop a robust high-throughput technique to perform these measurements comprehensively and efficiently. However, MCD spectroscopy requires very high optical quality for each component of the instrument, and even slight cell distortions can impair the baseline flatness. Consequently, when versatility and data quality are important, an optical system designed for a microplate reader is not suitable for the MCD spectrometer. Therefore, in this study, we develop a new magnetic flow-through cell and combine it with an existing CD spectrometer and autosampler to construct a high-throughput system. The effectiveness and performance of this new system are then evaluated. In addition, based on the MCD and absorption spectra of various phthalocyanine complexes, the effects of substituents and solvents on their magnetic and optical properties and the causes of these effects are discussed. The results demonstrate that this system is effective for the evaluation of the physicochemical properties of various phthalocyanine complexes.

3.
Cancer Cell Int ; 21(1): 546, 2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34663305

RESUMEN

BACKGROUND: Malignant mesothelioma (MM) is a very aggressive tumor that develops from mesothelial cells, mainly due to asbestos exposure. MM is categorized into three major histological subtypes: epithelioid, sarcomatoid, and biphasic, with the biphasic subtype containing both epithelioid and sarcomatoid components. Patients with sarcomatoid mesothelioma usually show a poorer prognosis than those with epithelioid mesothelioma, but it is not clear how these morphological phenotypes are determined or changed during the oncogenic transformation of mesothelial cells. METHODS: We introduced the E6 and E7 genes of human papillomavirus type 16 and human telomerase reverse transcriptase gene in human peritoneal mesothelial cells and established three morphologically different types of immortalized mesothelial cell lines. RESULTS: HOMC-B1 cells exhibited epithelioid morphology, HOMC-A4 cells were fibroblast-like, spindle-shaped, and HOMC-D4 cells had an intermediate morphology, indicating that these three cell lines closely mimicked the histological subtypes of MM. Gene expression profiling revealed increased expression of NOD-like receptor signaling-related genes in HOMC-A4 cells. Notably, the combination treatment of HOMC-D4 cells with TGF-ß and IL-1ß induced a morphological change from intermediate to sarcomatoid morphology. CONCLUSIONS: Our established cell lines are useful for elucidating the fundamental mechanisms of mesothelial cell transformation and mesothelial-to-mesenchymal transition.

4.
BMC Pulm Med ; 17(1): 175, 2017 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-29212495

RESUMEN

BACKGROUND: When epidermal growth factor receptor (EGFR) gene mutation-positive non-small cell lung cancer (NSCLC) acquires resistance to the initial tyrosine kinase inhibitor (TKI) treatment, reassessing the tumor DNA by re-biopsy is essential for further treatment selection. However, the process of TKI-sensitive tumor re-progression and whether re-biopsy is possible in all cases of acquired resistance to EGFR-TKI remain unclear. METHODS: We retrospectively analyzed data from 69 consecutive patients with EGFR gene mutation-positive advanced NSCLC who had been treated with EGFR-TKI and exhibited disease relapse after initial disease remission. The relapsing lesions were identified at the time of RECIST-progressive disease (PD) and clinical-PD (when the attending physician judged the patient as clinically relapsing and stopped EGFR-TKI therapy). We determined the potential re-biopsy methods for each relapsing lesion and evaluated their feasibility according to difficulty and invasiveness criteria as follows: category A, accessible by conventional biopsy techniques; category B, difficult (but possible) to biopsy and accessible with invasive methods; and category C, extremely difficult to biopsy or inaccessible without using highly invasive methods, including surgical biopsy. RESULTS: The total feasibility rate of re-biopsy (category A or B) was 68% at RECIST-PD and 84% at clinical-PD, and the most common accessible relapsing lesions were primary tumors at RECIST-PD and pleural effusion at clinical-PD. All relapsing lesions at primary sites (categories A and B) were assessed as having the potential for re-biopsy. However, re-biopsy for metastasis was assessed as difficult in a substantial proportion of the study population (42 and 20% category C at RECIST-PD and clinical-PD, respectively). CONCLUSIONS: Re-biopsy of relapsing disease is feasible in many cases, although it may present difficulties in cases with, e.g., metastatic relapsing lesions. To facilitate treatment strategies in NSCLC patients with relapse after EGFR-TKI therapy, re-biopsy should be standardized with the use of simpler and more reliable methods.


Asunto(s)
Adenocarcinoma/genética , Biopsia/métodos , Carcinoma de Pulmón de Células no Pequeñas/genética , Resistencia a Antineoplásicos , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Recurrencia Local de Neoplasia/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Broncoscopía , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Cohortes , Progresión de la Enfermedad , Receptores ErbB/antagonistas & inhibidores , Estudios de Factibilidad , Femenino , Humanos , Biopsia Guiada por Imagen , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
5.
Appl Spectrosc ; 78(2): 186-196, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38111257

RESUMEN

Attenuated total reflection infrared (ATR-IR, 4000-400 cm-1), ATR-far-IR (ATR-FIR, 400-50 cm-1), and Raman spectra (4000-10 cm-1) were measured for calcium carbonate, three kinds of minerals (calcite, aragonite, and quartz), two kinds of rocks (obsidian and pumice), and four kinds of biogenic minerals, i.e., coral (aragonite), Ruditapes philippinarum (aragonite), Meretrix lusoria (aragonite), and Corbicula japonica (aragonite), to investigate the polymorphism of minerals and biogenic minerals, differences in the crystal structure among aragonite and aragonite biogenic minerals, water in the minerals and biogenic minerals, Boson peaks of obsidian and pumice, very small amounts of carotenoids in the three kinds of shells, and so on. In this study, we put some emphasis on the low-frequency region of IR (FIR) and Raman spectra. ATR-FIR spectra were measured down to 50 cm-1 and Raman spectra were obtained down to 10 cm-1. Second derivative spectra were calculated for the FIR spectra. It has been found from the present study that the FIR spectra are the most powerful for exploring polymorphism and differences in the crystal structure among aragonite and aragonite biogenic minerals. A Boson peak, which is a characteristic low-frequency Raman band for amorphous materials, was observed at around 40 cm-1 in the Raman spectra of obsidian and pumice. The Boson peak of pumice is located at a lower frequency by 12 cm-1 than that of obsidian, indicating that the mean atomic volume of pumice is larger than that of obsidian. The present study has revealed that IR spectra are useful to investigate the amounts and structure of fluid and bound water. Moreover, it has also been found that Raman spectra can detect a very tiny amount of carotenoids in the shells due to the resonance Raman effect.

6.
PLoS One ; 19(6): e0301769, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38875175

RESUMEN

Despite the overwhelming evidence of climate change and its effects on future generations, most individuals are still hesitant to make environmental changes that would especially benefit future generations. In this study, we investigate whether dialogue can influence people's altruistic behavior toward future generations of humans, and how it may be affected by participant age and the appearance of the conversation partner. We used a human, an android robot called Telenoid, and a speaker as representatives of future generations. Participants were split among an old age group and a young age group and were randomly assigned to converse with one of the aforementioned representatives. We asked the participants to play a round of the Dictator Game with the representative they were assigned, followed by an interactive conversation and another round of the Dictator Game in order to gauge their level of altruism. The results show that, on average, participants gave more money after having an interactive conversation, and that older adults tend to give more money than young adults. There were no significant differences between the three representatives. The results show that empathy might have been the most important factor in the increase in altruistic behavior for all participants.


Asunto(s)
Altruismo , Comunicación , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Anciano , Empatía , Persona de Mediana Edad , Factores de Edad
7.
Cancer Med ; 12(12): 13586-13598, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37165917

RESUMEN

BACKGROUND: Mesothelioma is a neoplastic disease associated with asbestos exposure. It is highly malignant and has a poor prognosis; thus, early detection is desirable. Recent whole-genome analysis has revealed that mesothelioma is characterized by a high frequency of mutations in a set of genes involved in the Hippo pathway, such as NF2 and LATS2. However, a rapid, simple, and precise method for finding mesothelioma with these mutations has not yet been established. METHODS: Clustering of Hippo pathway gene alteration groups and the differential expression of each gene in mesothelioma patients were analyzed using The Cancer Genome Atlas database. Gene expression levels in various tumors and normal tissues were analyzed using public databases. Knockdown or transient expression of YAP1 or TAZ was performed to evaluate the regulation of gene expression by these genes. NT-proBNP was measured in the pleural effusions of 18 patients and was compared with NF2 expression in five cases where cell lines had been successfully established. RESULTS: NPPB mRNA expression was markedly higher in the group of mesothelioma patients with Hippo pathway gene mutations than in the group without them. NPPB expression was low in all normal tissues except heart, and was highest in mesothelioma. Mesothelioma patients in the high NPPB expression group had a significantly worse prognosis than those in the low NPPB expression group. NPPB expression was suppressed by knockdown of YAP1 or TAZ. NT-proBNP was abundant in the effusions of mesothelioma patients and was particularly high in those with impaired NF2 expression. CONCLUSIONS: NPPB, whose levels can be measured in pleural effusions of mesothelioma patients, has the potential to act as a biomarker to detect NF2-Hippo pathway gene alterations and/or predict patient prognosis. Additionally, it may provide useful molecular insights for a better understanding of mesothelioma pathogenesis and for the development of novel therapies.


Asunto(s)
Mesotelioma Maligno , Mesotelioma , Derrame Pleural , Humanos , Vía de Señalización Hippo , Mesotelioma/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Supresoras de Tumor/metabolismo
8.
Proc Natl Acad Sci U S A ; 105(13): 5093-8, 2008 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-18362351

RESUMEN

Anhydrobiosis is an extremely dehydrated state in which organisms show no detectable metabolism but retain the ability to revive after rehydration. Thus far, two hypotheses have been proposed to explain how cells are protected during dehydration: (i) water replacement by compatible solutes and (ii) vitrification. The present study provides direct physiological and physicochemical evidence for these hypotheses in an African chironomid, Polypedilum vanderplanki, which is the largest multicellular animal capable of anhydrobiosis. Differential scanning calorimetry measurements and Fourier-transform infrared (FTIR) analyses indicated that the anhydrobiotic larvae were in a glassy state up to as high as 65 degrees C. Changing from the glassy to the rubbery state by either heating or allowing slight moisture uptake greatly decreased the survival rate of dehydrated larvae. In addition, FTIR spectra showed that sugars formed hydrogen bonds with phospholipids and that membranes remained in the liquid-crystalline state in the anhydrobiotic larvae. These results indicate that larvae of P. vanderplanki survive extreme dehydration by replacing the normal intracellular medium with a biological glass. When entering anhydrobiosis, P. vanderplanki accumulated nonreducing disaccharide trehalose that was uniformly distributed throughout the dehydrated body by FTIR microscopic mapping image. Therefore, we assume that trehalose plays important roles in water replacement and intracellular glass formation, although other compounds are surely involved in these phenomena.


Asunto(s)
Chironomidae/química , Chironomidae/metabolismo , Agua/química , Agua/metabolismo , África , Animales , Fenómenos Químicos , Química Física , Chironomidae/crecimiento & desarrollo , Desecación , Vidrio , Larva/química , Larva/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Trehalosa/metabolismo
9.
Mol Cancer Res ; 19(5): 921-931, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33574130

RESUMEN

Malignant mesothelioma (MM) is an aggressive tumor that typically develops after a long latency following asbestos exposure. Although mechanistic target of rapamycin complex 1 (mTORC1) activation enhances MM cell growth, the mTORC1 inhibitor everolimus has shown limited efficacy in clinical trials of MM patients. We explored the mechanism underlying mTORC1 activation in MM cells and its effects on cell proliferation and progression. Analysis of the expression profiles of 87 MMs from The Cancer Genome Atlas revealed that 40 samples (46%) displayed altered expression of RPTOR (mTORC1 component) and genes immediately upstream that activate mTORC1. Among them, we focused on RHEB and RHEBL1, which encode direct activators of mTORC1. Exogenous RHEBL1 expression enhanced MM cell growth, indicating that RHEB-mTORC1 signaling acts as a pro-oncogenic cascade. We investigated molecules that directly activate RHEBs, identifying SmgGDS as a novel RHEB-binding protein. SmgGDS knockdown reduced mTORC1 activation and inhibited the proliferation of MM cells with mTORC1 activation. Interestingly, SmgGDS displayed high binding affinity with inactive GDP-bound RHEBL1, and its knockdown reduced cytosolic RHEBL1 without affecting its activation. These findings suggest that SmgGDS retains GDP-bound RHEBs in the cytosol, whereas GTP-bound RHEBs are localized on intracellular membranes to promote mTORC1 activation. We revealed a novel role for SmgGDS in the RHEB-mTORC1 pathway and its potential as a therapeutic target in MM with aberrant mTORC1 activation. IMPLICATIONS: Our data showing that SmgGDS regulates RHEB localization to activate mTORC1 indicate that SmgGDS can be used as a new therapeutic target for MM exhibiting mTORC1 activation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas del Citoesqueleto/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Mesotelioma Maligno/genética , Proteína Homóloga de Ras Enriquecida en el Cerebro/metabolismo , Animales , Proliferación Celular/fisiología , Femenino , Células HEK293 , Células HeLa , Humanos , Mesotelioma Maligno/patología , Ratones , Ratones Desnudos
10.
PLoS One ; 13(11): e0206972, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30452447

RESUMEN

Lymphocyte profiles in mediastinal lymph nodes may reflect the immune status of patients with sarcoidosis. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is useful for the diagnosis of diseases with mediastinal lymphadenopathy including sarcoidosis. The purpose of this study was to determine lymphocyte profiles of lymph nodes in sarcoidosis by analyzing EBUS-TBNA samples. We prepared single cell suspensions from EBUS-TBNA samples of mediastinal lymph nodes from patients with sarcoidosis or lung cancer and analyzed surface markers (CD3, CD4, CD8, CD19, CD25) and FoxP3 expression in the resultant lymphocytes using flow cytometry. We studied 26 patients with sarcoidosis and 16 with lung cancer with mediastinal lymph node metastases. In sarcoidosis, the CD4/CD8 ratio was significantly more elevated in lymph nodes than in bronchoalveolar lavage fluid (P<0.001), although both were strongly correlated. The CD4/CD8 ratio was significantly higher in stage I than in stage II both in the BAL fluid and lymph nodes. When compared with lung cancer lymph node metastasis, the CD4/CD8 ratio was significantly higher in sarcoidosis, whereas the CD3/CD19 ratio was significantly higher in lung cancer. The proportion of regulatory T cells (CD4+, CD25+, FoxP3 high) did not differ between sarcoidosis and lung cancer samples. Lymphocyte profiles in mediastinal lymphadenopathy can be analyzed by flow cytometry of EBUS-TBNA samples. These findings might help elucidate the immunopathology of sarcoidosis.


Asunto(s)
Citometría de Flujo , Linfadenopatía/metabolismo , Linfocitos/metabolismo , Enfermedades del Mediastino/metabolismo , Sarcoidosis/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Biopsia , Relación CD4-CD8 , Femenino , Citometría de Flujo/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Linfadenopatía/diagnóstico , Masculino , Enfermedades del Mediastino/diagnóstico , Persona de Mediana Edad , Sarcoidosis/diagnóstico , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Adulto Joven
11.
Carbohydr Res ; 337(19): 1729-35, 2002 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-12423951

RESUMEN

Form II is a kind of metastable crystalline form of trehalose anhydrate, and it is easily converted to the dihydrate crystal by absorbing water in moist atmosphere at room temperature (Akao et al., Carbohydr. Res. 2001, 334, 233-241). It can be utilized as an edible and nontoxic desiccant, and thus its efficient production from the dihydrate is significant from a viewpoint of industrial applications. In this study, we attempt to extract crystal water from the dihydrate using supercritical CO(2). We examine the dependence of extraction efficiency on the extraction time, the temperature and pressure of the fluid. Then, FTIR measurements are carried out to detect the extracted water and to identify the polymorphic phase of the sugar sample after the extraction treatment. In particular, the so-called first derivative euclidean distance analysis for IR spectra is shown to be quite useful for the structural identification. Consequently, we demonstrate that form II is produced from the dihydrate through supercritical CO(2) fluid extraction if appropriate temperature and pressure conditions (around 80 degrees C and 20 MPa) are maintained.


Asunto(s)
Dióxido de Carbono/química , Cromatografía con Fluido Supercrítico/métodos , Trehalosa/química , Agua/química , Cromatografía con Fluido Supercrítico/instrumentación , Cristalización , Cinética , Presión , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
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