The origin of OB runaway stars.

About 20% of all massive stars in the Milky Way have unusually high velocities, the origin of which has puzzled astronomers for half a century. We argue that these velocities originate from strong gravitational interactions between single stars and binaries in the centers of star clusters. The ejecting binary forms naturally during the collapse of a young (≤1 million years old) star cluster. This model replicates the key characteristics of OB runaways in our galaxy, and it explains the presence of runaway stars of ≥100 solar masses (M(⊙)) around young star clusters, such as R136 and Westerlund 2. The high proportion and the distributions in mass and velocity of runaways in the Milky Way are reproduced if the majority of massive stars are born in dense and relatively low-mass (5000 to 10,000 M(⊙)) clusters.

Risk factors for oxaliplatin-induced hypersensitivity reactions in Japanese patients with advanced colorectal cancer.

OBJECTIVE: Previously, we suggested that oxaliplatin (L-OHP)-related grade 3/4 hypersensitivity reactions occurred immediately after the initiation, but grade 1/2 reactions did not. This study was conducted to clarify the risk factors for L-OHP-related hypersensitivity reactions. METHODS: Clinical data from 108 Japanese patients with colorectal cancer were analyzed, who were treated with L-OHP-containing regimens, FOLFOX4 and/or mFOLFOX6. The risk factors examined included demographic data, preexisting allergies, laboratory test data, treatment regimen, treatment line of therapy, pretreatment with steroids, total number of cycles and cumulative amount of L-OHP. RESULTS: The incidence of grade 1/2 and grade 3/4 hypersensitivity reactions were found at 13.0% (14/108) and 9.3% (10/108), respectively. Female (P = 0.037), preexisting allergies (P = 0.004) and lower level of lactate dehydrogenase (P = 0.003) were risk factors for grade 1/2 hypersensitivity reactions, and higher neutrophil count (P = 0.043) and lower monocyte count (P = 0.007) were for grade 3/4 reactions. Total number of cycles were larger in the patients with grade 3/4 reactions than those without reactions (P = 0.049). CONCLUSIONS: Further extensive examination with a large number of patients is needed to establish a patient management strategy.

[A case of rapidly progressing lung spindle cell carcinoma presenting as Pancoast syndrome].

We report a case of rapidly progressing spindle cell carcinoma presenting as Pancoast syndrome. The patient was a 59-year-old woman with a chief complaint of right forearm paresthesia. A chest computed tomography revealed a huge tumor in S1 and S2 in the right lung, invading the upper mediastinum and the first rib. A CT-guided lung biopsy was performed. H-E stain of the tissue revealed spindle-shaped tumor cells proliferating diffusely in a streaming pattern without definitive squamous or glandular differentiation. Immunohistochemical stains with CAM 5.2 and vimentin were positive for tumor cells. Based on a pathological diagnosis of spindle cell carcinoma (cT4N3M1, stage IV) she was treated with chemoradiotherapy. Despite treatment, the patient died 6 months after presenting.

[Micafungin therapy for a case of chronic necrotizing pulmonary aspergillosis].

The patient was a 42-year-old man who visited a physician with fever, and was diagnosed with pulmonary abscess. Antibiotic therapy was ineffective, and he was referred to our hospital. Chest CT scanning revealed a lesion with cavity formation with an infiltrative shadow in the right upper lobe, and another infiltrative shadow in the left upper lobe. Chronic necrotizing pulmonary aspergillosis (CNPA) was diagnosed on the basis of positive culture of bronchial lavage specimens and positive serological test results for Aspergillus, in addition to the clinical and radiographic features. Intravenous administration of micafungin (MCFG) was initiated with combination therapy of percutaneous cavity drainage, inhaled amphotericin B and oral itraconazole. Clinical symptoms and findings gradually improved, and he was discharged after 40 days of MCFG therapy. MCFG was safe and effective therapy in this case, and may be considered a new therapeutic option for CNPA.

Solution structure of a tmRNA-binding protein, SmpB, from Thermus thermophilus.

Small protein B (SmpB) is required for trans-translation, binding specifically to tmRNA. We show here the solution structure of SmpB from an extremely thermophilic bacterium, Thermus thermophilus HB8, determined by heteronuclear nuclear magnetic resonance methods. The core of the protein consists of an antiparallel beta-barrel twisted up from eight beta-strands, each end of which is capped with the second or third helix, and the first helix is located beside the barrel. Its C-terminal sequence (20 residues), which is rich in basic residues, shows a poorly structured form, as often seen in isolated ribosomal proteins. The results are discussed in relation to the oligonucleotide binding fold.