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1.
Chemphyschem ; 24(4): e202200618, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36287210

RESUMO

We report the water adsorption/desorption behavior and dynamic magnetic properties of the Pt-Cl chain complex [{[Pt(en)2 ][PtCl2 (en)2 ]}3 ][{(MnCl5 )Cl3 }2 ] ⋅ 12H2 O (1). Upon heating 1 in a vacuum, we obtained the dehydrated form [{[Pt(en)2 ][PtCl2 (en)2 ]}3 ][{(MnCl5 )Cl3 }2 ] (1DH). The framework structures of 1 and 1DH are identical, and both complexes underwent slow magnetic relaxation. However, the magnetic relaxation times for 1DH were shorter than those for 1, meaning that the dynamic magnetic properties were controlled upon water vapor adsorption/desorption. From detailed analyses of the dynamic magnetic behavior, a phonon-bottleneck effect contributes to the magnetic relaxation processes. We discuss the mechanism for the changes in the magnetic relaxation processes upon dehydration in terms of the heat capacity and thermal conductivity.

2.
Chemphyschem ; 23(6): e202200120, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35244957

RESUMO

The front cover artwork is provided by Prof. Masahiro Yamashita's group at Tohoku University and designed by Dr. Laurent Guérin at University of Rennes 1. The image illustrates that the atomic structure of a 2D charge density wave can be revealed although the planes associated to this local 2D order are randomly stacked preventing the use of conventional structure determination techniques. Read the full text of the Research Article at 10.1002/cphc.202100857.

3.
Chemphyschem ; 23(6): e202100857, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35083834

RESUMO

Many solids, particularly low-dimensional systems, exhibit charge density waves (CDWs). In one dimension, charge density waves are well understood, but in two dimensions, their structure and their origin are difficult to reveal. Herein, the 2D charge-density-wave atomic structure and stabilization mechanism in the bromide-bridged Pd compound [Pd(cptn)2 Br]Br2 (cptn=1R,2R-diaminocyclopentane) is investigated by means of single-crystal X-ray diffraction employing the 3D-Δpair distribution function (3D-ΔPDF) method. Analysis of the diffuse scattering using 3D-ΔPDF shows that a 2D-CDW is stabilized by a hydrogen-bonding network between Br- counteranion and the amine (NH2 ) group of the cptn in-plane ligand, and that 3D ordering is prevented due to a weak plane to plane correlation. We extract the effective displacements of the atoms describing the atomic structure quantitatively and discuss the stabilization mechanism of the 2D-CDW. Our study provides a method to identify and measure the key interaction responsible for the dimensionality and stability of the CDW that can help further progress of rational design.

4.
Inorg Chem ; 61(25): 9504-9513, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35695034

RESUMO

Halogen-bridged linear chain metal complexes (MX-Chains) are fascinating compounds that have a quasi-one-dimensional (1D) electronic system. In this study, we synthesized the first Ni-based MX-Chain compound having hydroxy groups, i.e., [Ni(dabdOH)2Br]Br2·[Ni(dabdOHx)2Br]0.5·(2-PrOH)0.25·(MeOH)0.25 (1·solvent, x = ∼0.6, dabdOH = (2S,3S)-2,3-diaminobutane-1,4-diol). Single-crystal X-ray diffraction revealed that the MX-Chains in 1·solvent formed sheets and single-chain structures in the superlattice. It suggested an MH-like state, whereas the polarized reflection and Raman spectra suggested a CDW-like state. Magnetic and electron spin resonance measurements revealed that both high-spin Ni(II) (∼15%) and low-spin Ni(III) (∼85%) sites are present in the chain structures, i.e., the metal sites show mixed valency. Therefore, we concluded that 1·solvent adopts an intermediate state between the MH and CDW states. Moreover, a single crystal of 1·solvent exhibited semiconductive characteristics along the chain direction. This finding represents a new structural and electronic state of 1D electronic systems as well as MX-Chains.

5.
Inorg Chem ; 61(35): 14067-14074, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36006962

RESUMO

In condensed matter, phase separation is strongly related to ferroelasticity, ferroelectricity, ferromagnetism, electron correlation, and crystallography. These ferroics are important for nano-electronic devices such as non-volatile memory. However, the quantitative information regarding the lattice (atomic) structure at the border of phase separation is unclear in many cases. Thus, to design electronic devices at the molecular level, a quantitative electron-lattice relationship must be established. Herein, we elucidated a PdII-PdIV/PdIII-PdIII phase transition and phase separation mechanism for [Pd(cptn)2Br]Br2 (cptn = 1R,2R-diaminocyclopentane), propagated through a hydrogen-bonding network. Although the Pd···Pd distance was used to determine the electronic state, the differences in the Pd···Pd distance and the optical gap between Mott-Hubbard (MH) and charge-density-wave (CDW) states were only 0.012 Å and 0.17 eV, respectively. The N-H···Br···H-N hydrogen-bonding network functioned as a jack, adjusting the structural difference dynamically, and allowing visible ferroelastic phase transition/separation in a fluctuating N2 gas flow. Additionally, the effect of the phase separation on the spin susceptibility and electrical conductivity were clarified to represent the quasi-epitaxial crystals among CDW-MH states. These results indicate that the phase transitions and separations could be controlled via atomic and molecular level modifications, such as the addition of hydrogen bonding.

6.
Gan To Kagaku Ryoho ; 49(13): 1509-1511, 2022 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-36733118

RESUMO

We report the findings from a retrospective study to determine the optimum treatment strategy for local recurrence following radical resection of rectal cancer. In our department, among all 430 patients that underwent radical resection of rectal cancer from 2012 to 2018, there were 28 patients that developed local recurrence. Of those patients, 12 underwent surgical treatment(Op group)and 16 did not(N-Op group). In the Op group, 8 patients underwent radical resection, of which 2 patients remained recurrence-free, and the other 6 patients developed recurrence. In the N-Op group, 6 patients were treated with systemic chemotherapy alone, a further 6 patients had palliative irradiation in addition to systemic chemotherapy, and the other 4 selected best supportive care(2 patients were treated with palliative irradiation). In the 8 patients who had palliative irradiation, 7 showed a decrease in numerical rating scale(NRS)after irradiation. The adverse events of palliative irradiation were scrotal dermatitis in 1 patient and perianal inflammation in another 3 patients. Our surgical results for local recurrence of rectal cancer in our department were worse in terms of recurrence rate, so these findings suggest that the preoperative surgical strategy could be reviewed, as well as the actual surgical methods such as the optimal circumferential resection margin. Palliative irradiation was found to be useful for pain control. However, the occurrence of adverse events remains a concern.


Assuntos
Neoplasias Retais , Humanos , Estudos Retrospectivos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Manejo da Dor , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/tratamento farmacológico , Estadiamento de Neoplasias
7.
J Am Chem Soc ; 143(13): 4891-4895, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33656871

RESUMO

Single-molecule magnets exhibit magnetic bistabililties at the molecular level, making them promising for molecule-based spintronics due to high magnetic densities. The incorporation of SMM behavior and electrical conductivity in one compound is rare because these two physical properties often do not operate in the same temperature range, which further hinders their use in practical applications. Here we present an organic-inorganic molecular hybrid, ß″-(BEDO-TTF)3[Co(pdms)2]·(MeCN)(H2O)2 (BO3) (BEDO-TTF = bis(ethylenedioxy)tetrathiafulvalene and H2pdms = 1,2-bis(methanesulfonamido)benzene), which manifests both metallic conduction (electrical conductivity up to 1000 S cm-1 at 12 K under 2.0 gigapascal pressure) and SMM behavior in the temperature range 12-26 K for the first time.

8.
Dis Colon Rectum ; 64(11): 1331-1341, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34623347

RESUMO

BACKGROUND: Systemic inflammation contributes to the progression of malignancies. The preoperative lymphocyte-to-C-reactive protein ratio has recently been shown to predict survival of patients with colorectal cancer who undergo surgery, but its prognostic value remains unclear in patients with unresectable metastatic colorectal cancer. OBJECTIVE: This study aimed to examine the prognostic values of inflammation-based prognostic scores in patients with metastatic colorectal cancer, focusing on the lymphocyte-to-C-reactive protein ratio. DESIGN: This is a retrospective study from a prospectively collected database. SETTINGS: This study was conducted at a high-volume multidisciplinary tertiary cancer center in Japan. PATIENTS: The subjects were 756 consecutive patients with unresectable metastatic colorectal cancer who received systemic chemotherapy from 2000 to 2015. The prognostic value of the lymphocyte-to-C-reactive protein ratio was evaluated by univariable and multivariable analyses. Time-dependent receiver operating characteristics curve analysis was conducted to compare the prognostic impact of the lymphocyte-to-C-reactive protein ratio with the impact of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, or the modified Glasgow Prognostic Score. MAIN OUTCOME MEASURES: The primary outcomes measured were the correlations of prognostic scores with overall survival. RESULTS: Median survival times of patients with high, intermediate, and low lymphocyte-to-C-reactive protein ratios were 29.4, 19.3, and 13.1 months (p < 0.001). In all subgroups according to key prognostic factors (performance status, use of targeted agents, pretreatment CEA levels, tumor sidedness, M category, and primary tumor resection), patient prognosis could be clearly stratified into 3 groups by the lymphocyte-to-C-reactive protein ratio. Multivariable analysis revealed that decreased lymphocyte-to-C-reactive protein ratio was independently associated with reduced survival (low vs high: HR 1.96, p < 0.001; intermediate vs high: HR 1.44, p < 0.001). The time-dependent receiver operating characteristics curve analysis revealed that the lymphocyte-to-C-reactive protein ratio was the most sensitive predictor of survival among all inflammation-based prognostic scores on a continuous basis. LIMITATIONS: This study was retrospective in nature. CONCLUSIONS: The lymphocyte-to-C-reactive protein ratio is a useful prognostic biomarker for unresectable metastatic colorectal cancer and could contribute to accurate prognostication and therapeutic decision making. See Video Abstract at http://links.lww.com/DCR/B600. RELACIN ENTRE LINFOCITOS Y PROTENA C ES EL SCORE PRONOSTICO INFLAMATORIO MAS SENSIBLE EN PACIENTES CON CNCER COLORRECTAL METASTSICO IRRESECABLE: ANTECEDENTES:La inflamación sistémica contribuye en la progresión de neoplasias malignas. Recientemente se ha demostrado que la proporción preoperatoria de linfocitos -proteína C reactiva predice la supervivencia de los pacientes con cáncer colorrectal que se sometieron a cirugía, pero su valor pronóstico sigue sin estar claro en pacientes con cáncer colorrectal metastásico irresecable.OBJETIVO:Evaluar el valor pronostico de los scores inflamtorios centrandose en linfocito- proteina c reactiva en pacientes con cáncer colorrectal metastásico.DISEÑO:Estudio retrospective evaluando una base de datos.AJUSTE:Este estudio se llevó a cabo en un centro oncológico terciario multidisciplinario de gran volumen en Japón.PACIENTES:Se incluyeron 756 pacientes consecutivos todos con cáncer colorrectal metastásico irresecable que recibieron quimioterapia sistémica de 2000 a 2015. El valor pronóstico de la proteína C reactiva se evaluó mediante análisis univariables y multivariables. Se realizó análisis de la curva de características operativas del receptor dependiente del tiempo para comparar el impacto pronóstico de la proteína linfocito-C-reactiva con el de la proporción de neutrófilos a linfocitos, la proporción de plaquetas a linfocitos, la proporción de linfocitos a monocitos o la proporción de puntuación pronóstica segun escala de Glasgow modificada.PRINCIPALES MEDIDAS DE RESULTADO:Correlacion de las puntuaciones pronósticas con la supervivencia global.RESULTADOS:La mediana de supervivencia de los pacientes con niveles altos, intermedios y bajos de proteína C reactiva de linfocitos fue de 29,4, 19,3 y 13,1 meses, respectivamente (p <0,001). En todos los subgrupos de acuerdo con los factores pronósticos clave (estado funcional, uso de agentes dirigidos, niveles de antígeno carcinoembrionario antes del tratamiento, lado del tumor, categoría M y resección del tumor primario), el pronóstico del paciente podría estratificarse claramente en tres grupos por linfocito a C- proteína reactiva. El análisis multivariable reveló que la disminución de linfocitos a proteína C reactiva se asoció de forma independiente con una supervivencia reducida (baja frente a alta: cociente de riesgo 1,96, p <0,001; intermedio frente a alto: cociente de riesgo 1,44, p <0,001). El análisis de la curva de características operativas del receptor dependiente del tiempo reveló que de linfocito a proteína C reactiva era el predictor de supervivencia más sensible entre todas las puntuaciones de pronóstico basadas en inflamación de forma continua.LIMITACIONES:Este estudio fue de naturaleza retrospectiva.CONCLUSIONES:La proteína C reactiva de linfocitos a C es un biomarcador pronóstico útil para el cáncer colorrectal metastásico irresecable y podría contribuir a un pronóstico preciso y a la toma de decisiones terapéuticas. Consulte Video Resumen en http://links.lww.com/DCR/B600.


Assuntos
Proteína C-Reativa/metabolismo , Neoplasias Colorretais/sangue , Neoplasias Colorretais/mortalidade , Contagem de Linfócitos , Idoso , Neoplasias Colorretais/secundário , Feminino , Humanos , Inflamação , Japão , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Taxa de Sobrevida
9.
Dis Colon Rectum ; 64(9): 1074-1082, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34397558

RESUMO

BACKGROUND: Whether prolonged survival with current chemotherapy using molecular target agents has changed the rate of primary tumor-related complications in patients with unresectable stage IV colorectal cancer is unclear. OBJECTIVE: This study aimed to investigate the rate of primary tumor-related complications among patients receiving targeted therapy as compared with patients receiving chemotherapy without molecular target agents. DESIGN: This was a retrospective review of data from a prospectively maintained database. SETTINGS: The study was conducted at a high-volume multidisciplinary tertiary cancer center in Japan. PATIENTS: Subjects were 352 consecutive patients with unresectable stage IV colorectal cancer who received systemic chemotherapy without primary tumor resection from 2001 to 2015. Patients were categorized into nontargeted and targeted groups according to the use of molecular target agents. MAIN OUTCOME MEASURES: Complication rates attributed to primary tumors were measured. RESULTS: Of the 352 patients, 159 were categorized into the nontargeted group and 193 patients into the targeted group. Competing risk-adjusted univariate analysis revealed that the primary tumor-related complication rates in the nontargeted group were 6.9% (95% CI, 3.8%-11.9%) at 1 year and 8.2% (95% CI, 4.8%-13.8%) at 2 years, whereas the targeted group had complication rates of 11.5% (95% CI, 7.5%-16.6%) at 1 year and 16.7% (95% CI, 12.4%-23.3%) at 2 years. Multivariate analysis revealed that the targeted group was ≈2 times more likely to have primary tumor-related complications (subdistribution HR = 2.04 (95% CI, 1.12-4.01); p = 0.020). Median survival time was 12.0 months in the nontargeted group and 24.1 months in the targeted group (p < 0.001). LIMITATIONS: This study was limited by the retrospective design. CONCLUSIONS: Targeted therapy was associated with a significantly increased risk of primary tumor-related complications during chemotherapy. However, targeted therapy also improved overall survival, making it a tolerable therapy. See Video Abstract at http://links.lww.com/DCR/B536. COMPLICACIONES PRIMARIAS RELACIONADAS CON EL TUMOR ENTRE PACIENTES CON CNCER COLORRECTAL EN ESTADIO IV IRRESECABLE EN LA ERA DE LA TERAPIA DIRIGIDA UN ANLISIS DE REGRESIN DEL RIESGO COMPETITIVO: ANTECEDENTES:No está claro si la supervivencia prolongada con la quimioterapia actual utilizando agentes moleculares dirigidos ha cambiado la tasa de complicaciones relacionadas con el tumor primario en pacientes con cáncer colorrectal en estadio IV irresecable.OBJETIVO:Este estudio tuvo como objetivo investigar la tasa de complicaciones relacionadas con el tumor primario entre los pacientes que reciben terapia dirigida, en comparación con pacientes que reciben quimioterapia sin agentes moleculares dirigidos.DISEÑO:Revisión retrospectiva de datos de una base de datos mantenida prospectivamente.ESCENARIO CLINICO:Centro oncológico de tercer nivel multidisciplinario de alto volumen en Japón.PACIENTES:352 pacientes consecutivos con cáncer colorrectal en estadio IV irresecable que recibieron quimioterapia sistémica sin resección del tumor primario entre 2001 y 2015. Los pacientes se clasificaron en grupos dirigidos y no dirigidos según el uso de agentes moleculares dirigidos.PRINCIPALES MEDIDAS DE VALORACION:Tasas de complicaciones debidas a tumores primarios.RESULTADOS:De los 352 pacientes, 159 se clasificaron en el grupo no dirigido y 193 pacientes en el grupo dirigido. El análisis univariado ajustado al riesgo competitivo reveló que las tasas de complicaciones primarias relacionadas con el tumor en el grupo no dirigido fueron del 6,9% (intervalo de confianza (IC) del 95%, 3,8 - 11,9%) al año y del 8,2% (IC del 95%, 4,8%). - 13,8%) a los dos años, mientras que el grupo dirigido tuvo tasas de complicaciones del 11,5% (IC del 95%, 7,5 - 16,6%) al año y del 16,7% (IC del 95%, 12,4 - 23,3%) a los dos años. El análisis multivariado reveló que el grupo dirigido tenía aproximadamente dos veces más probabilidades de tener complicaciones relacionadas con el tumor primario (razón de riesgo de subdistribución, 2,04; IC del 95%, 1,12 a 4,01; p = 0,020). La mediana del tiempo de supervivencia fue de 12,0 meses en el grupo no dirigido y de 24,1 meses en el grupo dirigido (p <0,001).LIMITACIONES:Este estudio estuvo limitado por el diseño retrospectivo.CONCLUSIONES:La terapia dirigida se asoció con un riesgo significativamente mayor de complicaciones relacionadas con el tumor primario durante la quimioterapia. Sin embargo, la terapia dirigida también mejoró la SG, convirtiéndola en una terapia tolerable. Consulte Video Resumen en http://links.lww.com/DCR/B536.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/complicações , Neoplasias Colorretais/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Obstrução Intestinal/etiologia , Terapia de Alvo Molecular , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bevacizumab/administração & dosagem , Cetuximab/administração & dosagem , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Perfuração Intestinal/etiologia , Irinotecano/administração & dosagem , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Panitumumabe/administração & dosagem , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida
10.
Chemistry ; 26(27): 6036-6049, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32045039

RESUMO

Acetato-bridged palladium-lanthanide tetranuclear heterometallic complexes of the form [Pd2 Ln2 (H2 O)2 (CH3 COO)10 ]⋅2 CH3 COOH [Ln2 =Ce2 (1), Pr2 (2), Nd2 (3), Sm2 (4), Tb2 (5), Dy2 (6), Dy0.2 Y1.8 (6''), Ho2 (7), Er2 (8), Er0.24 Y1.7 (8''), Tm2 (9), Yb2 (10), Y2 (11)] were synthesised and characterised by experimental and theoretical techniques. All complexes containing Kramers lanthanide ions [Ln3+ =Ce (1), Nd (3), Sm (4), Dy (6), DyY (6''), Er (8), ErY (8''), Yb (10)] showed field-induced slow magnetic relaxation, characteristic of single-molecule magnetism and purely of molecular origin. In contrast, all non-Kramers lanthanide ions [Ln3+ =Pr (2), Tb (5), Ho (7), Tm (9), Y3+ (11) is diamagnetic and non-lanthanide] did not show any slow magnetic relaxation. The variation in the electronic structure and accompanying consequences across the complexes representing all Kramers and non-Kramers lanthanide ions were investigated. The origin of the magnetic properties and the extent to which the axial donor-acceptor interaction involving the lanthanide ions and an electron-deficient d z 2 orbital of palladium affects the observed magnetic and electronic properties across the lanthanide series are presented. Unique consistent electronic and magnetic properties of isostructural complexes spanning the lanthanide series with properties dependent on whether the ions are Kramers or non-Kramers are reported.

11.
BMC Cancer ; 20(1): 1092, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176752

RESUMO

BACKGROUND: This study aimed to evaluate the prognostic impact of nutritional and inflammatory measures (controlling nutritional status (CONUT) score, prognostic nutritional index (PNI), and modified Glasgow prognostic score (mGPS)) on overall survival (OS) in patients with stage IV colorectal cancer (CRC). METHODS: Subjects were 996 patients with stage IV CRC who were referred to the National Cancer Center Hospital between 2001 and 2015. We retrospectively investigated correlations between OS and CONUT score, PNI, and mGPS. Multivariate analyses were performed using Cox proportional hazards regression models. RESULTS: After adjusting for known factors (age, gender, BMI, ECOG performance status, location of primary tumor, CEA levels, histological type, M category, and prior surgical treatment), all three measures were found to be independent prognostic factors for OS in patients with stage (CONUT score, p < 0.001; PNI, p < 0.001; mGPS, p < 0.001). Significant differences in OS were found between low CONUT score (0/1) (n = 614; 61%) and intermediate CONUT score (2/3) (n = 276; 28%) (hazard ratio (HR) = 1.20, 95% confidence interval (CI): 1.02-1.42, p = 0.032), and intermediate CONUT score and high CONUT score (≥4) (n = 106; 11%) (HR = 1.30, 95% CI: 1.01-1.67, p = 0.045). Significant differences in OS were found between mGPS = 0 (n = 633; 64%) and mGPS = 1 (n = 234; 23%) (HR = 1.84, 95% CI: 1.54-2.19, p < 0.001), but not between mGPS = 1 and mGPS = 2 (n = 129; 13%) (HR = 1.12, 95% CI: 0.88-1.41, p = 0.349). Patients with low PNI (< 48.0) (n = 443; 44%) showed a significantly lower OS rate than those with high PNI (≥48.0) (n = 553; 56%) (HR = 1.39, 95% CI: 1.19-1.62, p < 0.001). CONCLUSIONS: CONUT score, PNI, and mGPS were found to be independent prognostic factors for OS in patients with stage IV CRC, suggesting that nutritional and inflammatory status is a useful host-related prognostic indicator in stage IV CRC.


Assuntos
Neoplasias Colorretais/mortalidade , Inflamação/fisiopatologia , Avaliação Nutricional , Estado Nutricional , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
12.
Macromol Rapid Commun ; 41(1): e1900384, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31588619

RESUMO

A novel terpyridine-based bimetallic metallo-supramolecular polymer (polyFeOs) containing alternately complexed Fe(II) and Os(II) ions is synthesized. For precise synthesis of the polymer, a new three-step synthetic pathway is developed to obtain a high yield (%) of product in each step. The first step is the synthesis of dibromo terpyridine-Os(II) complex in 87% yield, the second step is the synthesis of bisterpyridine ligand containing Os(II) (OsL1) in 74% yield, and the last step is the synthesis of polyFeOs in 90% yield. The polyFeOs exhibits high thermal stability with two degradation temperatures at around 390 and 690 °C, which indicate thermal evaporation of the counter anions (Cl- and BF4 - ) and degradation of the coordination bonds, respectively. The combination of two different metal ions in polyFeOs results in an enlarged optical window (λ = 315-675 nm) and two highly stable reversible redox states, which can be of huge interest for potential optical, electro-optical, and electrochemical applications.


Assuntos
Compostos Ferrosos/química , Osmio/química , Polímeros/química , Complexos de Coordenação/química , Íons/química , Ligantes , Polímeros/síntese química , Piridinas/química
13.
Angew Chem Int Ed Engl ; 59(6): 2399-2406, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31782883

RESUMO

The first three-dimensional (3D) conductive single-ion magnet (SIM), (TTF)2 [Co(pdms)2 ] (TTF=tetrathiafulvalene and H2 pdms=1,2-bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt3 ]2 [M(pdms)2 ] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)2 ]n- and the TTF.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)2 ]n- donor and TTF.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor-acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)2 [Co(pdms)2 ] (2-Co) is an excellent building block for preparing new conductive SIMs.

14.
J Am Chem Soc ; 141(17): 6802-6806, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30998332

RESUMO

The first porous molecular conductor (PMC), which exhibits porosity, a through-space conduction pathway and rich charge carriers (electrons), was prepared through electrocrystallization from Cd2+ and N, N'-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxdiimide (NDI-py). [Cd(NDI-py)(OH2)4](NO3)1.3±0.1· nDMA (PMC-1) was assembled by π-π stacking among one-dimensional (1D) linear coordination polymers. The NDI cores were partially reduced into radical anions to form conductive π-stacked columns, yielding (1.0-3.3) × 10-3 S cm-1 at room temperature. Moreover, the electrical conductivity was significantly enhanced by removing the solvent molecules from PMC-1, indicating that PMCs are promising as molecule-responsive conductive materials.

15.
Ann Surg Oncol ; 26(5): 1569-1576, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30847751

RESUMO

BACKGROUND: Two procedures widely performed to treat locally advanced colorectal cancer adherent to the urinary bladder are total cystectomy (as part of pelvic exenteration) and partial cystectomy; however, little is known about outcomes following partial cystectomy. METHODS: A retrospective database of patients with colorectal cancer involving the urinary bladder who underwent R0 or R1 resection at our institution from 2001 to 2015 was constructed. The histological extent of bladder invasion and long-term outcomes were examined. RESULTS: Of the 89 consecutive patients, 49 underwent partial cystectomy and all had negative margins of the bladder. Tumor invasion to the urinary bladder was confirmed histologically in 19 of 49 patients (coincidence rate of diagnosis, 39%): invasion only to the bladder serosa (n = 3), invasion to the bladder muscle (n = 4), and invasion beyond the bladder muscle without (n = 1) and with (n = 11) exposure to the bladder lumen. The 5-year recurrence-free and overall survival rates were 63.2% and 70.2% in the partial cystectomy group, and 66.2% and 72.7% in the total cystectomy group (p = 0.567 and 0.648), respectively. Except for the remnant bladder, recurrence sites were very similar to sites observed in patients who underwent total cystectomy. Intravesical recurrence occurred in four patients 3-13 months after the initial surgery, all of whom showed bladder lumen exposure to the tumor. CONCLUSIONS: With regard to long-term outcomes and low diagnostic concordance rates of clinical and pathological bladder invasion, partial cystectomy seems a generally acceptable treatment option. However, when the bladder lumen is exposed to a colorectal tumor, surgeons should be cognizant of possible intravesical recurrence and act accordingly.


Assuntos
Neoplasias Colorretais/mortalidade , Cistectomia/mortalidade , Recidiva Local de Neoplasia/mortalidade , Complicações Pós-Operatórias , Neoplasias da Bexiga Urinária/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Cistectomia/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia , Adulto Jovem
16.
Ann Surg Oncol ; 26(5): 1358-1365, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30719633

RESUMO

BACKGROUND: When treated with molecular targeted agents, patients with unresectable colorectal cancer with right-sided tumors have poorer prognoses than those with left-sided tumors. While primary tumor sidedness may have prognostic value, the prognostic value of tumor sidedness in chemotherapy regimens without targeted therapy is unclear. METHODS: Our study population comprised 678 consecutive patients with unresectable stage IV colorectal cancer who received systemic chemotherapy at the National Cancer Center Hospital in Japan from 1999 to 2015. Patients were stratified by treatment subgroup (with or without molecular targeted agents and with or without palliative primary tumor resection), and relationships between overall survival (OS) and primary tumor sidedness were evaluated. Multivariate analyses were also performed. RESULTS: Overall, 193 (28%) tumors were right-sided (cecum to transverse colon) and 485 (72%) were left-sided (splenic flexure to rectum). In the overall population, median survival time was 16.4 months for those with right-sided tumors and 23.4 months for those with left-sided tumors (p < 0.01). Regardless of the use or non-use of targeted agents and performance or non-performance of palliative resection of the primary tumor, those with right-sided tumors showed significantly poorer prognosis than those with left-sided tumors, in all categories. Multivariate analyses showed right-sided tumors to be associated with shorter OS compared with left-sided tumors (hazard ratio 1.26, 95% confidence interval 1.03-1.53; p =0.024). CONCLUSION: Unresectable stage IV right-sided colorectal tumors were associated with shorter OS compared with left-sided tumors, regardless of treatment strategy. Primary tumor sidedness may be an independent prognostic factor.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Adenocarcinoma/tratamento farmacológico , Idoso , Neoplasias Colorretais/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
17.
Ann Surg Oncol ; 25(6): 1646-1653, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29572704

RESUMO

BACKGROUND: The National Comprehensive Cancer Network guidelines recommend R0 resection and targeted therapy, a combination of cytotoxic and molecular targeted agents, such as bevacizumab, cetuximab, and panitumumab, for colorectal cancer with synchronous peritoneal metastasis (M1c). While these therapeutic strategies are drawing attention, their efficacy has not been fully examined. METHODS: The study population comprised 248 consecutive M1c patients who were treated at the National Cancer Center Hospital from 1997 to 2013. Multivariate analyses were performed to evaluate relationships between overall survival and R0 resection and targeted therapy using Cox proportional hazards regression models. RESULTS: The 3-year overall survival (3 yOS) was 19.5%, and median survival time (MST) was 16.2 months in 248 M1c patients. R0 resection was performed in 34 patients (14%), yielding a 3-year overall survival (OS) of 48.3% and median survival time (MST) of 29.9 months. Targeted therapy was performed in 54 patients (22%) at least once during the course of treatment, yielding a 3-yr OS of 38.2% and MST of 23.9 months. After adjusting for other key clinical factors, such as the number of organs involved with metastases, performance status, primary tumor site, and extent of peritoneal metastasis, both R0 resection and targeted therapy were independent factors associated with longer OS. Targeted therapy was associated with a significantly longer OS compared with multiple cytotoxic agent therapy [hazard ratio 0.65; 95% confidence interval (0.44-0.94); p = 0.02]. CONCLUSIONS: If achievable, R0 resection is a desirable therapeutic strategy for patients with M1c colorectal cancer. Moreover, targeted therapy might be the optimal chemotherapy in this patient population.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Bevacizumab/administração & dosagem , Cetuximab/administração & dosagem , Feminino , Fluoruracila/uso terapêutico , Humanos , Irinotecano/administração & dosagem , Masculino , Terapia de Alvo Molecular , Oxaliplatina/administração & dosagem , Panitumumabe/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Retais , Taxa de Sobrevida , Fatores de Tempo
18.
Chemistry ; 24(37): 9285-9294, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29663534

RESUMO

Incorporating palladium in the first coordination sphere of acetato-bridged lanthanoid complexes, [Pd2 Ln2 (H2 O)2 (AcO)10 ]⋅2 AcOH (Ln=Gd (1), Y (2), Gd0.4 Y1.6 (3), Eu (4)), led to significant bonding interactions between the palladium and the lanthanoid ions, which were demonstrated by experimental and theoretical methods. We found that electron density was donated from the d8 Pd2+ ion to Gd3+ ion in 1 and 3, leading to the observed slow magnetic relaxation by using local orbital locator (LOL) and X-ray absorption near-edge structure (XANES) analysis. Field-induced dual slow magnetic relaxation was observed for 1 up to 20 K. Complex 3 and frozen aqueous and acetonitrile solutions of 1 showed only one relaxation peak, which confirms the role of intermolecular dipolar interactions in slowing the magnetic relaxation of 1. The slow magnetic relaxation occurred through a combination of Orbach and Direct processes with the highest pre-exponential factor (τo =0.06 s) reported so far for a gadolinium complex exhibiting slow magnetic relaxation. The results revealed that transition metal-lanthanoid (TM-Ln) axial interactions indeed could lead to new physical properties by affecting both the electronic and magnetic states of the compounds.

19.
BMC Cancer ; 18(1): 334, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29587683

RESUMO

BACKGROUND: The incidence of colorectal cancer in adolescent and young adult patients is increasing. However, survival and clinical features of young patients, especially those with stage IV disease, relative to adult patients remain unclear. METHODS: This retrospective single-institution cohort study was conducted at a tertiary care cancer center. Subjects were 861 consecutive patients who were diagnosed with stage IV colorectal cancer at the age of 15 to 74 years and who were referred to the division of surgery or gastrointestinal oncology at the National Cancer Center Hospital from 1999 to 2013. Overall survival (OS) was investigated and clinicopathological variables were analyzed for prognostic significance. RESULTS: Of these, 66 (8%) were adolescent and young adult patients and 795 (92%) were adult patients. Median survival time was 13.6 months in adolescent and young adult patients and 22.4 months in adult patients, and 5-year OS rates were 17.3% and 20.3%, respectively, indicating significant worse prognosis of adolescent and young adult patients (p = 0.042). However, age itself was not an independent factor associated with prognosis by multivariate analysis. When compared with adult patients, adolescent and young adult patients consisted of higher proportion of the patients who did not undergo resection of primary tumor, which was an independent factor associated with poor prognosis in multivariate analysis. In patients who did not undergo resection (n = 349), OS of adolescent and young adult patients were significantly worse (p = 0.033). CONCLUSIONS: Prognoses were worse in adolescent and young adult patients with stage IV colorectal cancer compared to adult patients in Japan, due to a higher proportion of patients who did not undergo resection with more advanced and severe disease, but not due to age itself.


Assuntos
Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Neoplasias Colorretais/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Vigilância da População , Prognóstico , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Adulto Jovem
20.
Chemistry ; 23(19): 4551-4556, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28248439

RESUMO

Heterometallic Gd-Pt complexes ([Gd2 Pt3 (H2 O)2 (SAc)12 ] (SAc=thioacetate), [Y1.4 Gd0.6 Pt3 (H2 O)2 (SAc)12 ], and [Gd2 Pt3 (H2 O)6 (SAc)12 ]⋅7 H2 O have been synthesized. The crystal structures and DFT calculations indicated a Gd-Pt heretometallic bond. Single-crystal ESR spectra determined the direction of magnetic anisotropy as direction of the Gd-Pt bond. In other words, the Gd-Pt bond dictates the direction of magnetic anisotropy. The heterometallic Gd-Pt bond lowers the symmetry of the Gd ion, splitting the Kramers doublet in a dc field. Thus, we observed clear field-induced slow magnetic relaxation of [Y1.4 Gd0.6 Pt3 (H2 O)2 (SAc)12 ] up to 36 K. The relaxation process was determined to be a direct process.

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