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1.
J Org Chem ; 87(5): 3647-3651, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35041408

RESUMO

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.

2.
BMC Surg ; 22(1): 210, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655170

RESUMO

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.


Assuntos
Traumatismos Abdominais , Hemostáticos , Doenças Vasculares , Hemoperitônio/etiologia , Hemoperitônio/cirurgia , Humanos , Laparotomia , Pontuação de Propensão , Estudos Retrospectivos
3.
Angew Chem Int Ed Engl ; 61(34): e202206428, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35676224

RESUMO

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.

4.
J Biol Chem ; 291(10): 4913-27, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26728457

RESUMO

Chronic kidney disease (CKD) is associated with an increase in serum retinol; however, the underlying mechanisms of this disorder are poorly characterized. Here, we found that the alteration of hepatic metabolism induced the accumulation of serum retinol in 5/6 nephrectomy (5/6Nx) mice. The liver is the major organ responsible for retinol metabolism; accordingly, microarray analysis revealed that the hepatic expression of most CYP genes was changed in 5/6Nx mice. In addition, D-box-binding protein (DBP), which controls the expression of several CYP genes, was significantly decreased in these mice. Cyp3a11 and Cyp26a1, encoding key proteins in retinol metabolism, showed the greatest decrease in expression in 5/6Nx mice, a process mediated by the decreased expression of DBP. Furthermore, an increase of plasma transforming growth factor-ß1 (TGF-ß1) in 5/6Nx mice led to the decreased expression of the Dbp gene. Consistent with these findings, the alterations of retinol metabolism and renal dysfunction in 5/6Nx mice were ameliorated by administration of an anti-TGF-ß1 antibody. We also show that the accumulation of serum retinol induced renal apoptosis in 5/6Nx mice fed a normal diet, whereas renal dysfunction was reduced in mice fed a retinol-free diet. These findings indicate that constitutive Dbp expression plays an important role in mediating hepatic dysfunction under CKD. Thus, the aggravation of renal dysfunction in patients with CKD might be prevented by a recovery of hepatic function, potentially through therapies targeting DBP and retinol.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fígado/metabolismo , Insuficiência Renal Crônica/metabolismo , Fatores de Transcrição/metabolismo , Animais , Apoptose , Células Cultivadas , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Ligação a DNA/genética , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Insuficiência Renal Crônica/patologia , Ácido Retinoico 4 Hidroxilase , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta1/metabolismo , Vitamina A/sangue
5.
Inorg Chem ; 55(15): 7314-6, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27428928

RESUMO

A new manganese complex, [Mn(Pc)(CN)]2O, was prepared by an electrocrystallization method. This material is a single-component molecular conductor that displays semiconducting behavior with room temperature conductivity of 4.5 × 10(-3) S cm(-1). Furthermore, we observed negative magnetoresistance at room temperature due to interaction between conduction π electrons and localized d spins. X-ray structural analysis and IR absorption spectroscopy indicated structural disorder. The magnetic susceptibility measurements suggested the unequal spin states of two manganese atoms owing to this structural disorder.

6.
Angew Chem Int Ed Engl ; 55(26): 7432-6, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27145376

RESUMO

Unique redox switching of orthoquinone-containing pentacyclic aromatic compounds with molecular hydrogen and oxygen in the presence of a palladium nanoparticle catalyst (SAPd) is disclosed. These molecules were predicted by in silico screening before synthesis. Efficient protocols for the synthesis of orthoquinone-containing aromatic compounds by palladium-mediated homocoupling and the benzoin condensation reaction were developed. Clear switching between orthoquinone and aromatic hydroquinone compounds was observed on the basis of their photoluminescence properties. Furthermore, the twist strain of the orthoquinone moiety could induce dramatic changes in color and emission.

7.
Chemistry ; 20(36): 11318-21, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25048397

RESUMO

A novel method for the fabrication of a charge-transfer complex crystal was developed. Photoirradiation of a solution of TPP[Co(tbp)(CN)(2)] and TPP[Co(Pc)(CN)(2)] (tbp=tetrabenzoporphyrin, Pc=phthalocyanine, TPP=tetraphenylphosphonium) gave a molecular conducting crystal of a charge-transfer complex TPP[Co(tbp)(CN)(2)](2), which was produced by the process in which the photoexcited electron in tbp was transferred from the LUMO of tbp to that of Pc.

8.
Chem Commun (Camb) ; 60(22): 3019-3022, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38288742

RESUMO

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.

9.
J Radiat Res ; 65(1): 127-135, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37996096

RESUMO

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.


Assuntos
Radioterapia (Especialidade) , Humanos , Japão , Inquéritos e Questionários , Aceleradores de Partículas
10.
Hepatogastroenterology ; 60(123): 590-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23282740

RESUMO

BACKGROUND/AIM: Anatomic resection of the liver is one of the essential techniques in liver surgery. However, parenchymal transection precisely along intersegmental planes is still a technically demanding procedure, and an optimal navigation method is required. METHODOLOGY: Real-time ultrasound monitoring with a probe applied from behind the liver was tried as a means of locating the site where resection was proceeding in the liver and confirming the direction of hepatic parenchymal transection to facilitate anatomic resection of the liver. RESULTS: The ultrasound navigation technique was performed during 11 hepatectomies in 10 patients in whom adequate retrohepatic space could be obtained to position the ultrasound probe. Continuous monitoring of the site in the liver where the resection was being performed was feasible, and the optimal direction of parenchymal transection was easily determined on the basis of the ultrasound images without interrupting the surgical maneuvers. The mean speed of parenchymal transection was faster (2.4cm2/min vs. 1.2cm2/min, p=0.009) and the amount of blood loss per transected area was smaller (4.4mL/cm2 vs. 7.2mL/cm2, p=0.05) in patients treated with the current technique. CONCLUSIONS: Continuous ultrasound monitoring of the liver facilitates the safe and precise parenchymal transection during anatomic resections of the liver.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Cirurgia Assistida por Computador , Ultrassonografia de Intervenção , Perda Sanguínea Cirúrgica/prevenção & controle , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Distribuição de Qui-Quadrado , Neoplasias Colorretais/patologia , Estudos de Viabilidade , Hepatectomia/efeitos adversos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Cirurgia Assistida por Computador/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
11.
Gan To Kagaku Ryoho ; 40(10): 1397-400, 2013 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-24196079

RESUMO

A 68-year-old man undergoing hemodialysis (HD) was diagnosed with recurrence of colon cancer and liver metastasis. He was treated with oxaliplatin, folinic acid and 5-fluorouracil (FOLFOX4), folinic acid, 5-fluorouracil and irinotecan (FOLFIRI), FOLFIRI+bevacizumab (BV), and cetuximab+irinotecan (CPT-11) as third-line therapy. Each drug was adequately reduced over time, but cetuximab was administered at the standard dose. The patient died of methicillin-resistant Staphylococcus aureus (MRSA) meningitis during the course of cetuximab+CPT-11 therapy, but there was no relation between the meningitis and the therapy. Therefore, each regimen can be safely performed, and cetuximab+CPT-11 therapy showed a significant anti-tumor effect and hence may be an effective regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Falência Renal Crônica/terapia , Terapia de Salvação , Idoso , Neoplasias do Colo/complicações , Humanos , Falência Renal Crônica/complicações , Masculino , Recidiva , Diálise Renal
12.
Gan To Kagaku Ryoho ; 40(12): 1659-61, 2013 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-24393880

RESUMO

A treatment strategy that includes adjuvant chemotherapy needs to be developed for the treatment of patients with multiple liver metastases of colorectal origin. Of the 91 patients who underwent initial hepatic resection for colorectal liver metastases, we reviewed the clinical courses of 10 patients who had 7 or more metastatic liver nodules. Twenty-one, 19, 17, and 9 metastases were initially resected in each of the 4 patients, and 7 metastases were resected in each of the remaining 6 patients. Portal vein embolization was performed in 3 patients, 2 of whom underwent two-stage hepatectomy. Adjuvant chemotherapy was administered to all the 10 patients. Recurrence was detected in all the 10 patients; however, in 6 of these patients, liver was the only site of recurrence. Repeated hepatic resection was performed in 5 of the 6 patients. As of the mean follow-up period of 25 months, 4 patients were alive and cancer-free, 4 were undergoing chemotherapy, and 2 had died of their cancer. Improvement in the survival outcome of patients with 7 or more colorectal liver metastases can be expected by treating them with adjuvant chemotherapy in addition to aggressive surgical procedures, including extended hemihepatectomy, portal venous embolization, two-stage hepatectomy, and repeated resection.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/cirurgia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Embolização Terapêutica , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
13.
Int J Surg Case Rep ; 104: 107913, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36774769

RESUMO

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.

14.
Abdom Radiol (NY) ; 48(11): 3353-3361, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37542553

RESUMO

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.

15.
Thorac Cancer ; 14(35): 3445-3452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37846145

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia Conformacional , Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/etiologia , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/etiologia , Radioterapia Conformacional/métodos
16.
Cancers (Basel) ; 15(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37686657

RESUMO

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.

17.
RSC Adv ; 12(28): 17944-17949, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35765347

RESUMO

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.

18.
Mol Clin Oncol ; 15(3): 187, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34349987

RESUMO

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.

19.
Dalton Trans ; 50(17): 5789-5794, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33876804

RESUMO

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.

20.
Dalton Trans ; 48(48): 17723-17728, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660554

RESUMO

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.

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