Subporphyrins with an axial B-C bond.

Axial fabrications of subporphyrins have been conveniently accomplished by the reaction of B(methoxo)triphenylsubporphyrin with Grignard reagents such as aryl-, heteroaryl-, ferrocenyl-, ß-styryl-, phenylethynyl-, and ethylmagnesium bromides. The axial groups thus introduced are not conjugated with the subporphyrin core. This situation leads to effective fluorescence quenching of subporphyrins when the axial group is strongly electron donating such as 4-dimethylaminophenyl and ferrocenyl groups.

[Mood States in outpatients with lesional epilepsy at the neurosurgical clinic and improvement in mood States after lamotrigine addiction].

People with epilepsy have a high incidence of mood disorders that may affect their quality of life. Lamotrigine(LTG)is one of the antiepileptic drugs that are commercially available in Japan these days and its mood-stabilizing qualities were well known. First, 66 outpatients with epilepsy were evaluated for changes in mood states by the Profile of Mood States(POMS)and the Japanese-edition Beck Depression Inventory-Second Edition(BDI-II)on self report. The POMS questionnaire includes 30 items that address six components of mood. At baseline, one third of the outpatients with epilepsy had mood problems compared by POMS health reference. The mean BDI-II baseline score was 14.9±10.1, and one third of these epilepsy patients exhibited moderate or severe depression. Second, in the twelve patients with epilepsy, LTG was added to other antiepileptic drugs, and the POMS and BDI-II were administered at baseline and after addiction to LTG. 4 out of 8(50%)patients with simple partial seizure and 5 out of 8(62.5%)patients after the adjunctive therapy experienced at least a 50% reduction in the number of seizures compared with the self-reported baseline before the adjunctive therapy. The component scores of Depression-Dejection, Anger-Hostility and Confusion-Bewilderment in POMS were statistically improved in these patients completing adjunctive LTG(pared t-test, p<0.05). In these patients, the mean BDI-II baseline score was 25.8±13.1. Following administration of LTG, there was a significant decrease in the mean BDI-II scores(15.0±6.6)between baseline and the end of adjunctive LTG. This study suggests that, in addition to seizure control, LTG may have a mood-stabilizing effect and improve the quality of life in patients with epilepsy.

Dissecting the Triplet-State Properties and Intersystem Crossing Mechanism of the Ligand-Protected Au13 Superatom.

Icosahedral Au13 nanoclusters are among the most typical superatoms and are of great interest as promising building blocks for nanocluster-assembled materials. Herein, the key parameters involved in the intersystem crossing (ISC) process of [Au13(dppe)5Cl2]3+ (Au13; dppe = 1,2-bis(diphenylphosphino)ethane) were characterized. Quenching experiments using aromatic compounds revealed that the T1 energy of Au13 is 1.63 eV. An integrative interpretation of our experimental results and the relevant literature uncovered important facts concerning the Au13 superatom: the ISC quantum yield is unity due to the ultrafast ISC (∼1012 s-1), the lowest absorption band includes contributions of direct singlet-triplet transitions, and there exists a large S1-T1 gap of 0.73 eV. To explain the efficient ISC, the El-Sayed rule was applied to the superatomic orbitals corresponding to the excited-state hole/electron distributions obtained from theoretical calculations. The strong spin-orbit coupling between the S1 and T2-T4 states offers a reasonable explanation for the ultrafast ISC.

Charge-Transfer-Mediated Mechanism Dominates Oxygen Quenching of Ligand-Protected Noble-Metal Cluster Photoluminescence.

Photoluminescence (PL) quenching of ligand-protected noble-metal clusters (NMCs) by molecular oxygen is often used to define whether the PL of NMC is fluorescent or phosphorescent, and only energy transfer has been always considered as the quenching mechanism. Herein, we performed the Rehm-Weller analysis of the O2-induced PL quenching of 13 different NMCs and found that the charge-transfer (CT)-mediated mechanism dominates the quenching process. The quenching rate constant showed a clear dependence on the CT driving force, varied markedly from 106 to 109 M-1s-1. Transient absorption spectroscopy and photon upconversion measurements confirmed the triplet sensitization of aromatic molecules by NMCs regardless of the quenching degree by O2, establishing that the PL of NMCs under investigation originates from the excited triplet state (i.e., phosphorescence). The results herein provide an essential indicator for correctly determining whether the PL of an NMC is fluorescent or phosphorescent.

Gamma Knife surgery for convexity, parasagittal, and falcine meningiomas.

OBJECT: The aim of this study was to evaluate the outcomes in patients with convexity, parasagittal, or falcine meningiomas treated using Gamma Knife surgery (GKS) and to determine management strategy considering a risk of radiation-induced edema. METHODS: One hundred twelve patients who harbored 125 convexity, parasagittal, or falcine meningiomas were assessed. Forty-six patients underwent GKS as the initial treatment. The median tumor diameter was 25 mm, and median tumor volume was 8 cm(3). The median maximum and margin doses were 30 and 16 Gy, respectively. RESULTS: The median follow-up period was 72 months. The actuarial 5- and 10-year progression-free survival rates were 78% and 55%, respectively. The actuarial 5- and 10-year local tumor control rates were 87% and 71%, respectively. Of 29 tumors that developed postradiosurgical edema, 7 were symptomatic. The actuarial symptomatic radiation-induced edema rate was 7%. The incidence of this complication was significantly higher in patients who underwent GKS as the initial treatment. Six of 46 patients for whom GKS was the initial treatment had preradiosurgical edema. Of these 6 patients, 4 developed severe panhemispheric edema after GKS (2 patients with parasagittal tumors, 1 with a falx tumor, and 1 with a convexity tumor). CONCLUSIONS: Gamma Knife surgery is an effective treatment for convexity, parasagittal, and falcine meningiomas as the initial or adjuvant treatment. However, GKS should be restricted to small- to medium-sized tumors, particularly in patients with primary tumors, because radiation-induced edema is more common in convexity, parasagittal, and falcine meningiomas than skull base meningiomas.

Stereotactic radiosurgery for pineal and related tumors.

Radiosurgery is increasingly being used to treat pineal region tumors, either as an additional therapy after conventional treatments or as a primary treatment. We report our experience with Gamma Knife radiosurgery (GKRS) for the treatment of pineal and related tumors. Forty-nine patients underwent GKRS for pineal and related tumors (n = 74) between February 1992 and September 2007. The diagnosis was germ cell tumors (GCTs) in 38 patients (53 tumors), pineal parenchymal tumors (PPTs) in 9 (19 tumors), and unknown in 2 (2 tumors). The mean treatment volume was 3.3 ml (range 0.1-22 ml) in GCT cases and 3.7 ml (range 0.3-23 ml) in PPT cases. Prescribed doses around 50% isodose line ranged from 9.9 to 25.7 Gy. One patient (one tumor) with pineocytoma was lost to follow-up. Median clinical and imaging follow-up in the remaining 48 cases was 33.5 months (range, 3-192 months). Survival rates at 5 years and 10 years after GKRS in GCT cases (n = 38) were both 68%. They were 100 and 67%, respectively, in PPT cases (n = 8). We evaluated the treatment results with categorization of GCT cases into 2 groups, i.e. germinoma (group 1), and germinoma with syncytiotrophoblastic giant cell and malignant GCT (group 2). PPT cases were also divided into 2 groups, i.e. pineocytoma (group 3) and pineoblastoma and mixed pineocytoma/pineoblastoma (group 4). Local tumor control (LTC) rates at 3 and 5 years were 82% in group 1 (n = 18), 72 and 62% in group 2 (n = 35), and 85% in group 3 (n = 13). LTC rate at 2 years was 30% in group 4 (n = 5). In group 1 (n = 16), progression-free survival (PFS) rates at 3 and 5 years were 79 and 63%. They were 43 and 37% in group 2 (n = 22), and 80% in group 3 (n = 5). PFS rate at 2 years was 33% in group 4 (n = 3). Germinoma and pineocytoma showed higher LTC and PFS rates after GKRS, though pineoblastoma was liable to relapse. Intermediate prognosis was obtained in germinoma with syncytiotrophoblastic giant cell and malignant GCT. GKRS is expected to be an effective and safe adjuvant treatment approach to pineal and related tumors.