Single-molecule quantum dot as a Kondo simulator.

Structural flexibility of molecule-based systems is key to realizing the novel functionalities. Tuning the structure in the atomic scale enables us to manipulate the quantum state in the molecule-based system. Here we present the reversible Hamiltonian manipulation in a single-molecule quantum dot consisting of an iron phthalocyanine molecule attached to an Au electrode and a scanning tunnelling microscope tip. We precisely controlled the position of Fe2+ ion in the molecular cage by using the tip, and tuned the Kondo coupling between the molecular spins and the Au electrode. Then, we realized the crossover between the strong-coupling Kondo regime and the weak-coupling regime governed by spin-orbit interaction in the molecule. The results open an avenue to simulate low-energy quantum many-body physics and quantum phase transition through the molecular flexibility.

A case of poorly differentiated hilar lung adenocarcinoma of an unidentified histological type.

The patient was a 74-year-old man, a physician, whose chief complaint was an unproductive cough. The shadow of a mass was seen at the hilum of the left lung, and the mediastinal lymph nodes on both sides were swollen. No histological diagnosis was obtained even after bronchoscopy, including transbronchial needle aspiration biopsy, but large-cell carcinoma of the lung was diagnosed on the basis of ultrasound-guided biopsy of a shadow in the liver suspected of being a metastatic tumor (T2N3M1, Stage IV). Two courses of chemotherapy (CBCDA + VDS) failed to gain any improvement, and the pain resulting from recurrent bone metastases was managed mainly by the administration of the best supportive care. The patient was readmitted to the hospital after development of numbness in the right upper extremity followed by complication of pneumonia and heart failure, and he passed away. Autopsy revealed a primary hilar lung tumor with a histological diagnosis of poorly differentiated adenocarcinoma.

Involvement of histone phosphorylation in thymocyte apoptosis by protein phosphatase inhibitors.

Incubation of rat thymocytes with the inhibitors of protein phosphatase such as calyculin A and okadaic acid resulted in an increase in DNA fragmentation. These effects were dependent on the concentration of the inhibitors and the incubation time. Analyses of the fragmented DNA revealed the production of approximately 50 kbp of DNA and a 180 bp DNA ladder. In addition, a laser scanning-microscopic analysis showed that these compounds caused nuclear condensation. Thus, these results demonstrated that protein phosphatase inhibitors induced thymocyte apoptosis. The inhibitors of protein phosphatase increased the phosphorylation of proteins of approximately 15 kDa. The phosphorylation of proteins preceded the DNA fragmentation induced by these inhibitors. Judging from acetic acid-urea-Triton X-100 gel electrophoresis, the phosphorylated proteins were histone H1 and H2A/H3. Therefore, these results suggest that phosphorylation of histones triggers the DNA fragmentation of thymocytes undergoing apoptosis.