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1.
Chem Commun (Camb) ; 60(22): 3019-3022, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38288742

RESUMEN

A single-component molecular radical crystal of CoIII(tbp˙-)(CN)2, where tbp = tetrabenzoporphyrinato ligand, exhibiting a diamond lattice was fabricated as a potential candidate for a three-dimensional Dirac electron system. Band structure calculations revealed that the Fermi energy level was located at the Dirac point. A small electrical resistivity of 160 Ω cm was observed at 2 K under the application of 2.4 GPa. Furthermore, substituting CoIII by FeIII or MnIII led to the introduction of local magnetic moments into the diamond-lattice system. MIII(tbp˙-)L2 crystals will open up uncharted fields in the study of the Dirac electron systems.

2.
J Radiat Res ; 65(1): 127-135, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-37996096

RESUMEN

The purpose of this study was to investigate the status of remote-radiotherapy treatment planning (RRTP) in Japan through a nationwide questionnaire survey. The survey was conducted between 29 June and 4 August 2022, at 834 facilities in Japan that were equipped with linear accelerators. The survey utilized a Google form that comprised 96 questions on facility information, information about the respondent, utilization of RRTP between facilities, usage for telework and the inclination to implement RRTPs in the respondent's facility. The survey analyzed the utilization of the RRTP system in four distinct implementation types: (i) utilization as a supportive facility, (ii) utilization as a treatment facility, (iii) utilization as a teleworker outside of the facility and (iv) utilization as a teleworker within the facility. The survey response rate was 58.4% (487 facilities responded). Among the facilities that responded, 10% (51 facilities) were implementing RRTP. 13 served as supportive facilities, 23 as treatment facilities, 17 as teleworkers outside of the facility and 5 as teleworkers within the facility. In terms of system usage between supportive and treatment facilities, 70-80% of the participants utilized the system for emergencies or as overtime work for external workers. A substantial number of facilities (38.8%) reported that they were unfamiliar with RRTP implementation. The survey showed that RRTP utilization in Japan is still limited, with a significant number of facilities unfamiliar with the technology. The study highlights the need for greater understanding and education about RRTP and financial funds of economical compensation.


Asunto(s)
Oncología por Radiación , Humanos , Japón , Encuestas y Cuestionarios , Aceleradores de Partículas
3.
Thorac Cancer ; 14(35): 3445-3452, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37846145

RESUMEN

BACKGROUND: The purpose of this study was to compare the dosimetric characteristics of five different treatment planning techniques for locally advanced non-small cell lung cancer (LA-NSCLC) with sequential plan changes. METHODS: A total of 13 stage III NSCLC patients were enrolled in this study. These patients had both computed tomography (CT) images for initial and boost treatment plans. The latter CT images were taken if tumor shrinkage was observed after 2 weeks of treatment. The prescription dose was 60 Gy/30 Fr (initial: 40 Gy/20 Fr, and boost: 20 Gy/10 Fr). Five techniques (forward-planed 3-dimensional conformal radiotherapy [F-3DCRT] on both CT images, inverse-planned 3DCRT [I-3DCRT] on both CT images, volumetric modulated arc therapy [VMAT] on both CT images, F-3DCRT on initial CT plus VMAT on boost CT [bVMAT], and hybrid of fixed intensity-modulated radiotherapy [IMRT] beams and VMAT beams on both CT images [hybrid]) were recalculated for all patients. The accumulated doses between initial and boost plans were compared among all treatment techniques. RESULTS: The conformity indexes (CI) of the planning target volume (PTV) of the five planning techniques were 0.34 ± 0.10, 0.57 ± 0.10, 0.86 ± 0.08, 0.61 ± 0.12, and 0.83 ± 0.11 for F-3DCRT, I-3DCRT, VMAT, bVMAT, and hybrid, respectively. In the same manner, lung volumes receiving >20 Gy (V20Gy ) were 21.05 ± 10.56%, 20.86 ± 6.45, 19.50 ± 7.38%, 19.98 ± 10.04%, and 17.74 ± 7.86%. There was significant improvement about CI and V20Gy for hybrid compared with F-3DCRT (p < 0.05). CONCLUSION: The IMRT/VMAT hybrid technique for LA-NSCLC patients improved target CI and reduced lung doses. Furthermore, if IMRT was not available initially, starting with 3DCRT might be beneficial as demonstrated in the bVMAT procedure of this study.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radioterapia Conformacional , Humanos , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/etiología , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/etiología , Radioterapia Conformacional/métodos
4.
Cancers (Basel) ; 15(17)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37686657

RESUMEN

Surgery is the standard treatment for stage I non-small cell lung cancer (NSCLC); however, no clear randomized trial demonstrates its superiority to stereotactic body radiotherapy (SBRT) regarding survival. We aimed to retrospectively evaluate the treatment outcomes of SBRT in operable patients with stage I NSCLC using a large Japanese multi-institutional database to show real-world outcome. Exactly 399 patients (median age 75 years; 262 males and 137 females) with stage I (IA 292, IB 107) histologically proven NSCLC (adenocarcinoma 267, squamous cell carcinoma 96, others 36) treated at 20 institutions were reviewed. SBRT was prescribed at a total dose of 48-70 Gy in 4-10 fractions. The median follow-up period was 38 months. Local progression-free survival rates were 84.2% in all patients and 86.1% in the T1, 78.6% in T2, 89.2% in adenocarcinoma, and 70.5% in squamous cell subgroups. Overall 3-year survival rates were 77.0% in all patients: 90.7% in females, 69.6% in males, and 41.2% in patients with pulmonary interstitial changes. Fatal radiation pneumonitis was observed in two patients, all of whom had pulmonary interstitial changes. This real-world evidence will be useful in shared decision-making for optimal treatment, including SBRT for operable stage I NSCLC, particularly in older patients.

5.
Abdom Radiol (NY) ; 48(11): 3353-3361, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37542553

RESUMEN

BACKGROUND: Stereotactic body radiotherapy (SBRT) is a local treatment option for hepatocellular carcinoma (HCC). SBRT-induced focal reactions on the liver parenchyma have not been thoroughly evaluated using quantitative magnetic resonance imaging (MRI). PURPOSE: To quantitatively evaluate liver parenchymal changes caused by SBRT for HCC using magnetic resonance elastography (MRE) and diffusion-weighted imaging (DWI). METHOD: We retrospectively evaluated 22 adult patients who received SBRT for HCC and 27 who received locoregional therapy other than SBRT (controls). Liver stiffness by MRE and apparent diffusion coefficient (ADC) values by DWI of the liver parenchyma were measured before and after SBRT. Regions of interest (ROIs) were drawn on the two areas of radiation dose distribution levels, > 30 Gy and ≤ 30 Gy; a ROI was drawn in the control group. The two indices were compared before and after SBRT using a Wilcoxon matched-pairs signed-rank test. RESULTS: Liver stiffness and ADC values were significantly increased after SBRT in the dose areas of > 30 Gy compared with those before SBRT (4.05 vs 4.85 kPa; p < 0.05 in liver stiffness, and 1.10 vs 1.40 ×10-3 s/mm2; p < 0.05 in ADC values). In the dose area of ≦ 30 Gy, liver stiffness showed a significant increase in one reader (p = 0.033) but not in another reader (p = 0.085); ADC value showed no significant difference before and after SBRT as per both readers (p > 0.05). The control group demonstrated no significant differences before and after treatment (p > 0.05). CONCLUSION: MRE and DWI can be used to detect SBRT-induced liver parenchymal changes.

6.
Int J Surg Case Rep ; 104: 107913, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36774769

RESUMEN

INTRODUCTION AND IMPORTANCE: Right-sided blunt diaphragmatic injury (BDI) is rare and often missed initially. Recently, some studies reported increased use of minimally invasive repair. A case of unexplained hemothorax that led to early suspicion of right-sided BDI, which was confirmed by exploratory thoracoscopy with an artificial pneumothorax, and primary repair was completed, is presented. CASE PRESENTATION: A 47-year-old woman had a moderate right hemothorax without rib fracture, vertebral fracture, or lung injury. A chest tube was inserted for the hemothorax, and approximately 470 mL of blood were evacuated initially. The right-sided BDI was not initially identified. Diagnostic thoracoscopy with an artificial pneumothorax confirmed diaphragmatic laceration. The liver was pushed back into the abdominal cavity with the use of the artificial pneumothorax. Primary closure of the diaphragmatic laceration was performed. CLINICAL DISCUSSION: We must consider that a hemothorax without a lung injury or a chest wall injury may be a BDI. Thoracoscopy contributes to identifying and repairing a diaphragmatic injury. Additionally, an artificial pneumothorax provided a good operative field and spontaneously reduced the liver into the abdominal cavity, which facilitates the thoracoscopic repair of BDI. CONCLUSION: Unexplained hemothorax may be due to diaphragmatic injury, and exploratory thoracoscopy with an artificial pneumothorax may contribute to identifying and repairing a diaphragmatic injury.

7.
Angew Chem Int Ed Engl ; 61(34): e202206428, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35676224

RESUMEN

The chemical carrier doping of molecular Mott insulators has been poorly investigated to date due to its difficulty. In this study, iodine doping of a molecular Mott insulator, lithium phthalocyanine crystallized in the x-form (x-LiPc), was performed to obtain metallic x-LiPcI. Crystal structure analysis revealed that iodine atoms penetrated channels of x-LiPc and formed one-dimensional chains. The Raman spectroscopy of x-LiPcI indicated the existence of linear I5 - , demonstrating a transition from a half-filled band of the Mott insulating state to a 2/5-filled band of the metallic state. Electrical resistivity measurements confirmed the metallic nature of x-LiPcI, whereas a thermally activated behavior was observed for pristine x-LiPc. Furthermore, the x-LiPc Mott insulator was reproduced by dedoping iodine from x-LiPcI, suggesting that the electronic state can be reversibly tuned between the Mott insulating and metallic states by chemical doping and dedoping.

8.
BMC Surg ; 22(1): 210, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35655170

RESUMEN

BACKGROUND: Currently, damage control surgery (DCS) employing multiple-staged laparotomy (MSL) is a standard hemostatic approach for treating trauma patients with unstable hemodynamics attributable to massive hemoperitoneum. Based on these findings, we had frequently employed MSL as a part of our hemostatic strategy for the patients, but with unsatisfactory outcomes. On the other hand, with the establishment of damage control resuscitation (DCR), it has become possible to avoid trauma-induced coagulopathy and to achieve adequate hemostasis with single-staged laparotomy (SSL). Consequently, our institutional strategy for surgical hemostasis of the patients has gradually shifted from MSL to SSL with implementation of DCR. The purpose of the study is to evaluate the impact of this shift in the strategy by comparing outcomes of the patients between those underwent MSL and those underwent SSL employing propensity score matching. METHODS: This retrospective, single-center, observational study evaluated outcomes of hemodynamically unstable patients with traumatic massive hemoperitoneum requiring surgical intervention between 2005 and 2020. The patient population was divided into two groups: a SSL group and a MSL group. Propensity score matching was used to adjust for differences in baseline characteristics in the two groups, a one-to-one matched analysis using nearest-neighbor matching was performed based on the estimated propensity score of each group. The primary outcome was in-hospital mortality, and secondary outcomes were 48-h mortality and 28-day mortality. RESULTS: A total of 170 patients met the inclusion criteria; 141 patients underwent SSL, and 29 underwent MSL. In the propensity-matched analysis with 27 pairs, the SSL group had significantly lower in-hospital mortality (odds ratio [OR] 0.154; 95% confidence interval (CI) 0.035 to 0.682) and 28-day mortality (OR 0.200; 95% CI 0.044 to 0.913) than the MSL group, but the 48-h mortality did not differ significantly between the two groups (25.9% vs. 44.4%; OR 0.375; 95% CI 0.099-1.414). CONCLUSIONS: Single-staged laparotomy may be an effective surgical treatment for the traumatic massive hemoperitoneum cases with hemodynamic instability, if conducted following sufficient damage control resuscitation and performed by an experienced surgeon.


Asunto(s)
Traumatismos Abdominales , Hemostáticos , Enfermedades Vasculares , Hemoperitoneo/etiología , Hemoperitoneo/cirugía , Humanos , Laparotomía , Puntaje de Propensión , Estudios Retrospectivos
9.
RSC Adv ; 12(28): 17944-17949, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35765347

RESUMEN

A design for an octahedrally ligated phthalocyanine complex with high-spin manganese(iii) (S = 2) and MnIII(Pc)Cl2 (Pc = phthalocyanine) is presented. The presence of high-spin state MnIII in the fabricated Ph4P[MnIII(Pc)Cl2]2 (Ph4P = tetraphenylphosphonium) semiconducting molecular crystal is indicated by the Mn-Cl distance, which suggests an electronic configuration of (d yz , d zx )2(d xy )1(d z 2 )1. This was confirmed by the Curie constant (C = 5.69 emu K mol-1), which was found to be significantly larger than that of the isostructural Ph4P[MnIII(Pc)(CN)2]2, where MnIII adopts a low-spin state (S = 1). The magnetoresistance (MR) effects of Ph4P[MnIII(Pc)Cl2]2 at 26.5 K under 9 T static magnetic fields perpendicular and parallel to the c-axis were determined to be -30% and -20%, respectively, which are significantly larger values than those of Ph4P[MnIII(Pc)(CN)2]2. Furthermore, the negative MR effect is comparable to that of Ph4P[FeIII(Pc)(CN)2]2 (S = 1/2), which exhibits the largest negative MR effect reported for [MIII(Mc)L2]-based systems (Mc = macrocyclic ligand, L = axial ligand). This suggests that the spin state of the metal ion is the key to tuning the MR effect.

10.
J Org Chem ; 87(5): 3647-3651, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35041408

RESUMEN

Borocyclic radicals with highly conjugated aromatics were generated from orthoquinone-containing polycyclic aromatic compounds by trapping the photoinduced triplet state with simple boron halide under irradiation with light of appropriate wavelength. The picene-based borocyclic radical was remarkably stable when stored at 23 °C in a desiccator for over 1 year. The crystal structure of this stable radical had a stacking structure of a planar π-conjugated system, and the electrical conductivity was higher than those of ordinary organic radical systems.

11.
Mol Clin Oncol ; 15(3): 187, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34349987

RESUMEN

The present report describes a case series in which spacers with boluses were used at various sites in the oral cavity to enhance the therapeutic effect of radiation therapy in oral squamous cell carcinoma. In radiotherapy, the surface dose is reduced due to the build-up region of X-rays. In the present study, a bolus was used to complement the build-up region and increase the surface dose effect. A total of 7 patients with oral cancer from a primary care hospital underwent radiation therapy using spacers and added boluses to improve the surface dose effect. The spacer was made from a plastic splint and the bolus was connected to the splint with a quick self-curing resin. There were no complaints of pain or adverse events from the patients while wearing the intraoral splint. A total of 2 of the 7 patients were subsequently confirmed as having progressed disease, and the remaining 5 are currently being managed following a complete response to treatment. The spacers used at various sites of oral squamous cell carcinoma were safe and effective and did not cause any severe adverse effects.

12.
Dalton Trans ; 50(17): 5789-5794, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33876804

RESUMEN

The field of molecular spintronics has gained significant attention for the development of second-generation spintronic devices. Therefore, an electrically conducting molecular crystal, Ph4P[FeIII(1,2-Nc)(CN)2]2 (Ph4P = tetraphenylphosphonium and 1,2-Nc = C4h isomer of 1,2-naphthalocyanine), was fabricated as a new coordination compound with a strong π-d interaction. Furthermore, it is a mixed-valence compound with a local spin of S = 1/2 at the center of the conduction path. Crystal structure analysis revealed that Ph4P[FeIII(1,2-Nc)(CN)2]2 was isostructural to its non-magnetic analogue Ph4P[CoIII(1,2-Nc)(CN)2]2 but possessed higher electrical resistivity, indicating that the strong intramolecular π-d interaction is present in the [FeIII(1,2-Nc)(CN)2] unit. Although the magnetic interaction between π-conduction electrons and FeIII-d spins (π-d interaction) is crucial for the emergence of a negative magnetoresistance effect, the negative magnetoresistance effect of Ph4P[FeIII(1,2-Nc)(CN)2]2 was significantly smaller (-6% at 30 K under a static 9 T magnetic field) than those of Ph4P[FeIII(Pc)(CN)2]2 (-32%) and Ph4P[FeIII(tbp)(CN)2]2 (-13%) analogues (Pc = phthalocyanine and tbp = tetrabenzoporphyrin). This small negative magnetoresistance effect of Ph4P[FeIII(Pc)(CN)2]2 could be ascribed to the weak intermolecular antiferromagnetic interaction between its d spins. Hence, this study showed that constructing a molecular design for strengthening the intermolecular antiferromagnetic interaction is key to enhancing the negative magnetoresistance effect.

13.
Dalton Trans ; 48(48): 17723-17728, 2019 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-31660554

RESUMEN

The effect of molecular modification on the intermolecular interactions in tetrabenzoporphyrin-based charge transfer complexes is reported. TPP[FeIII(tbp)Cl2]2, TPP[CoIII(tbp)Cl2]2 and TPP[CoIII(tbp)Br2]2 (TPP = tetraphenylphosphonium and tbp = tetrabenzoporphyrin) were synthesized and their crystal structures were compared to those of the reported TPP[MIII(tbp)(CN)2]2, TPP[FeIII(tbp)Br2]2 and TPP[MIII(Pc)L2]2 complexes (Pc = phthalocyanine; and L = CN, Cl or Br). The prepared CT complexes were isostructural to reported systems. However, their intermolecular interactions were found to depend on the combination of the macrocyclic (Mc) and axial ligands (L). In Pc-based systems, the overlap integral between HOMOs of Pc decreased with the increase in the size of the axial ligand, which indicated that the intermolecular interactions in Pc-based systems were dominated by repulsive interactions. On the other hand, in tbp-based systems, attractive and repulsive interactions competed with each other. Furthermore, charge transport properties were found to depend on the central metal ion as well as the combination of Mc and L, which suggested that minor molecular modifications to porphyrin complexes will cause drastic changes in both inter- and intramolecular interactions.

14.
World Neurosurg ; 122: 144-149, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30391614

RESUMEN

BACKGROUND: Upper thoracic myelopathy caused by combined ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) is relatively rare. This clinical condition is difficult to treat, and a surgical method has not been fully established. We report an extremely rare case of severe thoracic myelopathy caused by concurrent beak-type OPLL and OLF at T1-T2. CASE DESCRIPTION: A 53-year-old woman with paresthesia of both legs and an inability to hold a standing position presented to our hospital. Radiological images showed a large beak-type OPLL at T1-T2 and an OLF at T1-T7. The spinal cord was severely compressed at T1-T2. First, posterior decompression and instrumentation fusion at C6-T4 was performed, with a T1-T2 bilateral parallel gutter along the dural tube into the vertebral bodies covering the extent of the OPLL. Second, anterior decompression of the OPLL with corpectomy of T1-T2 and fusion using iliac bone grafting was performed after the sternal manubrium splitting approach. In the deep operating field of the second surgery, the gutters created during the first surgery were helpful for judging the width and thickness of the OPLL during the anterior decompression procedure. Postoperatively, her neurological symptoms greatly improved, the patient could walk independently, and the Japanese Orthopaedic Association score had improved from 3 preoperatively to 8 at the final follow-up examination at 16 months postoperatively. CONCLUSIONS: Two-stage circumferential decompression and fusion surgery can be considered an effective surgical method for upper thoracic concurrent OPLL and OLF. The bilateral gutters created during the first surgery improved the safety and feasibility of this difficult operation.


Asunto(s)
Descompresión Quirúrgica , Osificación del Ligamento Longitudinal Posterior/cirugía , Enfermedades de la Médula Espinal/cirugía , Fusión Vertebral , Vértebras Torácicas/cirugía , Femenino , Humanos , Persona de Mediana Edad , Osificación del Ligamento Longitudinal Posterior/complicaciones , Osificación del Ligamento Longitudinal Posterior/diagnóstico por imagen , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/etiología , Vértebras Torácicas/diagnóstico por imagen
15.
Org Lett ; 20(9): 2534-2537, 2018 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-29652164

RESUMEN

α-Ketocarbenium ions derived from synthesized orthoquinone-containing polycyclic aromatic compounds were generated in the presence of Brønsted acids such as sulfuric acid, trifluoromethanesulfonic acid, and fluorosulfonic acid. The prepared α-ketocarbenium ions were stabilized by conjugation of the aromatic moiety. In addition, unique absorption properties of the α-ketocarbenium ions were observed and identified on the basis of the calculated absorption spectra. It was suggested that the zigzag-shaped architecture stabilizes the newly discovered α-ketocarbenium ions derived from orthoquinone-containing polycyclic aromatic compounds.

16.
Dalton Trans ; 47(12): 4070-4075, 2018 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-29417967

RESUMEN

A porphyrin-based octahedrally ligated complex with high-spin iron(iii) was designed, and the resulting electrically conducting crystal TPP[FeIII(tbp)Br2]2 (TPP = tetraphenylphosphonium and tbp = tetrabenzoporphyrin) was synthesised. Although TPP[Fe(tbp)Br2]2 was isostructural to the reported TPP[Fe(Mc)L2]2 systems (Mc = macrocyclic ligands such as phthalocyanine (Pc) or tbp; and L = CN, Cl, or Br), the bond lengths between Fe and ligands in the [Fe(tbp)Br2] unit were evidently longer than those in the other units, because of the different spin states of Fe: high-spin in TPP[Fe(tbp)Br2]2 and low-spin in others. The magnetic anisotropy observed in the low-spin state vanished when the Fe is in the high-spin state. Based on reports for Pc-based systems, the negative magnetoresistance (MR) effect for TPP[Fe(tbp)Br2]2 was expected to be smaller than that for TPP[Fe(tbp)(CN)2]2. However, the former showed a giant negative MR effect similar to or larger than the latter, suggesting that the nature of iron is a crucial factor for the electrical properties of porphyrin-based materials.

17.
Dalton Trans ; 46(35): 11800-11805, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28831481

RESUMEN

Introduction of asymmetry into charge-transfer complexes composed of axially ligated iron phthalocyanines was achieved. In the obtained crystals of TPP[FeIII(Pc)(CN)Cl]2, TPP[FeIII(Pc)(CN)Br]2, and TPP[FeIII(Pc)BrCl]2 (TPP = tetraphenylphosphonium and Pc = phthalocyanine), the axial positions of the iron atoms were occupied by 50/50 ratios of the ligands CN/Cl, CN/Br, and Br/Cl, respectively. The crystal structures of the obtained CT complexes were isostructural to those composed of the symmetric analogues of the type [FeIII(Pc)L2] (L = CN, Cl or Br); the [FeIII(Pc)LL'] units formed regular one-dimensional chains along the c-axis following the symmetry of the P42/n space group. Despite forming similar regular chains to the symmetric systems, the electrical resistivities and activation energies were enhanced in the obtained CT complexes compared to those in symmetric systems, indicating that the charge-ordered states were stabilised by the introduction of asymmetry. More specifically, the dielectric relaxation behaviour of the inhomogeneous disordered TPP[FeIII(Pc)(CN)Cl]2 probably suggests that a dipole moment was induced in this material.

18.
Dalton Trans ; 46(6): 1892-1897, 2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28106221

RESUMEN

A conducting molecular crystal TPP[MnIII(Pc)(CN)2]2 (MnIII: d4, S = 1, TPP = tetraphenylphosphonium and Pc = phthalocyanine) was fabricated. In its crystal structure, the [MnIII(Pc)(CN)2] units formed a one-dimensional regular chain along the c-axis with an overlap integral value of 8.6 × 10-3. TPP[MnIII(Pc)(CN)2]2 showed a semiconducting behaviour that also has been observed for isostructural TPP[CoIII(Pc)(CN)2]2 (CoIII: d6, S = 0) and TPP[FeIII(Pc)(CN)2]2 (FeIII: d5, S = 1/2) whose ground states are charge-ordered states. In spite of the local magnetic moment of the MnIII ion (S = 1) at the centre of the Pc ligand, TPP[MnIII(Pc)(CN)2]2 exhibited an almost isotropic and small negative magnetoresistance (MR) effect (the MR ratio was -8.7% under 8 T at 10.7 K), contrarily to the anisotropic giant negative MR effect of TPP[FeIII(Pc)(CN)2]2. The isotropy was found to be due to a (dxz)1(dyz)1 electronic configuration, and the smaller MR effect was explained by a weaker antiferromagnetic interaction between MnIII ions than that between FeIII ions, as suggested by a Weiss temperature Θ of -3.1 K (|Jdd|/kB = 1.2 K).

19.
EBioMedicine ; 13: 262-273, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27745900

RESUMEN

Chronic kidney disease (CKD) is a global health problem, and novel therapies to treat CKD are urgently needed. Here, we show that inhibition of G0/G1 switch 2 (G0s2) ameliorates renal inflammation in a mouse model of CKD. Renal expression of chemokine (C-C motif) ligand 2 (Ccl2) was increased in response to p65 activation in the kidneys of wild-type 5/6 nephrectomy (5/6Nx) mice. Moreover, 5/6Nx Clk/Clk mice, which carry homozygous mutations in the gene encoding circadian locomotor output cycles kaput (CLOCK), did not exhibit aggravation of apoptosis or induction of F4/80-positive cells. The renal expression of G0s2 in wild-type 5/6Nx mice was important for the transactivation of Ccl2 by p65. These pathologies were ameliorated by G0s2 knockdown. Furthermore, a novel small-molecule inhibitor of G0s2 expression was identified by high-throughput chemical screening, and the inhibitor suppressed renal inflammation in 5/6Nx mice. These findings indicated that G0s2 inhibitors may have applications in the treatment of CKD.


Asunto(s)
Proteínas de Ciclo Celular/genética , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/patología , Animales , Sitios de Unión , Proteínas CLOCK/genética , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Quimiocina CCL2/genética , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Expresión Génica , Regulación de la Expresión Génica , Masculino , Ratones , Ratones Noqueados , Unión Proteica , ARN Interferente Pequeño/genética , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Factor de Transcripción ReIA/metabolismo , Transcripción Genética
20.
Dalton Trans ; 45(42): 16604-16609, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27477610

RESUMEN

By measuring the electrical resistivity in TPP[FeIII(tbp)(CN)2]2 (TPP = tetraphenylphosphonium and tbp = tetrabenzoporphyrin) under the application of a static magnetic field, a giant negative magnetoresistance (MR) effect with high anisotropy is observed. More specifically, the MR ratio at 13 K under a field of 9 T perpendicular to the c axis is -70%, whereas the MR ratio under a field parallel to the c axis is -40%. Furthermore, electron spin resonance (ESR) measurements indicate large anisotropy in the principal g-values of d spin (S = 1/2) in the [FeIII(tbp)(CN)2] unit; the g1 value almost perpendicular to the tbp plane and the g2 and g3 values almost parallel to the tbp plane are 3.60, 1.24, and 0.39, respectively. It is revealed that the anisotropy in the MR effect arises from the anisotropy in the d spin, suggesting that the d spins in TPP[FeIII(tbp)(CN)2]2 affect the π-conduction electron via the intramolecular π-d interaction. The anisotropy and magnitude in the giant negative MR effect for TPP[FeIII(tbp)(CN)2]2 are smaller than the corresponding values for the isostructural phthalocyanine (Pc) analogue TPP[FeIII(Pc)(CN)2]2. This is consistent with the fact that the intermolecular antiferromagnetic d-d interaction in TPP[FeIII(tbp)(CN)2]2 (suggested by the Weiss temperature: Θ = -8.0 K) is weaker than that in TPP[FeIII(Pc)(CN)2]2 (Θ = -12.3 K). This indicates that the minor modification in coordination complexes can significantly affect the MR effect via tuning the intermolecular d-d interaction as well as the intermolecular π-π overlap.

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