Effects of different types of extracellular polysaccharides isolated from cyanobacterial blooms on the colony formation of unicellular Microcystis aeruginosa.

In this study, two types of extracellular polysaccharides (EPS), namely, mixed EPS (MX-EPS) and tightly bound EPS (TB-EPS), were extracted from cyanobacterial blooms using different methods. To evaluate their compositional differences, elemental composition, FTIR, and TG/DTA profile were measured for both EPS samples. Following that, unicellular Microcystis aeruginosa was cultured in a medium containing EPS, Ca2+ ion, and Mg2+ ion, and the effect of each type of EPS on the colony formation of M. aeruginosa was examined. Results showed that TB-EPS had more carboxy groups than MX-EPS, and that the TB-EPS medium contained Ca2+ and Mg2+ ions. These cations were not detected in the MX-EPS medium. During the colony formation experiment, colonies were observed when Ca2+ and Mg2+ ions were present at 250 mg/L concentration each. In addition, colony density increased when TB-EPS was added, compared to that of MX-EPS. Colonies were also observed in the medium containing only TB-EPS (100 mg/L), indicating that M. aeruginosa can form colonies using Ca2+ ion present in TB-EPS. During the MX-EPS extraction, Ca2+ ion chelated with EDTA was removed during ethanol precipitation. Therefore, the extraction protocol followed for TB-EPS was better than that of MX-EPS for maintaining Ca2+ ions, and thereby maintaining an EPS composition that enables for colony formation.

Prognostic impact of the primary tumor location based on the hilar structures in non-small cell lung cancer with mediastinal lymph node metastasis.

The status of mediastinal lymph node metastasis is one of the main factors determining the treatment strategy for non-small cell lung cancer (NSCLC), but the primary tumor location is not considered crucial in the tumor-node-metastasis (TMN) classification at present. The aim of this study was to estimate the prognostic value of the primary tumor location on the basis of the hilar structures in NSCLC with mediastinal lymph node metastasis. We retrospectively reviewed the cases of 337 consecutive patients who underwent surgical resection for NSCLC between 1995 and 2004, divided the pN2 NSCLC cases (n=40) into central- and peripheral-type tumors according to the distance of the primary tumor from the first branch of the extrapulmonary bronchus, and compared the surgical outcomes between these tumor groups. Eighteen and twenty-two cases were classified as central- and peripheral-type tumors, respectively. The 5-year survival rate was significantly better for patients with central-type tumors than peripheral-type tumors (51.5% vs. 21.2%, P=0.034). The location-specific prognostic tendency was noted irrespective of the presence (n=13) or absence of skip metastasis. In a multivariate Cox analysis of the N2 NSCLC cases, the primary tumor location was a significant (P=0.026) prognostic factor for overall survival. In conclusion, evaluation of the primary tumor location based on the hilar structures is useful to predict the prognosis in N2 NSCLC.

Unilateral absence of the left pulmonary artery accompanied by right lung cancer.

Unilateral absence of a pulmonary artery is a rare congenital anomaly that is often accompanied by other cardiovascular anomalies. Surgical treatment for this rare disease is usually performed only on the abnormal side. We report on a case of unilateral absence of a pulmonary artery that was complicated by contralateral primary lung cancer. We performed a right middle lobectomy despite the absence of the left pulmonary artery and detected changes in respiratory function during the operation. The present case provides information on the surgical tolerability and predictable morbidity following lung resection of the normal side in unilateral absence of a pulmonary artery.

Superselective segmentectomy for deep and small pulmonary nodules under the guidance of three-dimensional reconstructed computed tomographic angiography.

BACKGROUND: Three-dimensional computed tomographic angiography (3D-CT angio) allows selective access to peripheral segments. Superselective segmentectomy (SSS) was applied to the surgical management of indeterminate small and deep pulmonary nodules. METHODS: Thirty patients with indeterminate pulmonary nodules less than 25 mm in diameter and located deeper than 20 mm from the pleural surface were enrolled in this study between 2002 and 2009. All patients underwent exploratory thoracotomy. The SSS with a surgical margin from the nodule larger than the nodule diameter or 20 mm was directed toward the target pulmonary arteries by 3D-CT angio using a multidetector-row CT scanner. The SSS was evaluated for resected area, surgical margin, regional lymph nodes, morbidity, lung function, and survival rate. RESULTS: Three patients received SSS at the daughter segment, 23 patients that at the subsegment, and the remaining four underwent miscellaneous SSS without major complications. Twenty patients exhibited early lung cancer, one patient stage IIA lung cancer, and the remaining nine patients had metastatic or benign tumors. Five patients with primary cancer subsequently underwent standard lobectomy. The remaining 16 patients with early lung cancer did not undergo lobectomy because of their major comorbidities or refusal of a second thoracotomy. The surgical margins were free of disease in all patients. The actual and disease-free five-year survival rates were 100% for the lung cancer patients, excluding those who subsequently underwent lobectomy. The lung function after SSS was well preserved. CONCLUSIONS: Superselective segmentectomy is an applicable optional strategy for the surgical management of indeterminate small and deep pulmonary nodules.

Active lactonizing lipase (LipL) efficiently overproduced by Pseudomonas strains as heterologous expression hosts.

Pseudomonas sp. strain 109 secretes lactonizing lipase (LipL), which catalyzes efficient intramolecular transesterification of omega-hydroxyfatty acid esters to form macrocyclic lactones. Because Escherichia coli was found to be unsuitable as an expression host due to the predominant formation of inactive LipL-inclusion bodies and a lack of proper secretion machinery which is also required for the formation of active LipL, Pseudomonas strains were surveyed as expression hosts. Pseudomonas sp. strain 109, an original LipL producer, showed a 7.1-fold higher level of active LipL when the lipL gene under the control of tac-lacUV5 tandem promoter was introduced together with a limL gene encoding a LipL-specific chaperon. Pseudomonas aeruginosa ADD 1976 containing a T7 RNA polymerase gene in the chromosome and plasmid-borne lipL-limL genes under the control of T7 promoter showed a 13-fold higher level of active LipL. Several combinations in the number of lipL and/or limL genes on the plasmid were investigated, and (lipL)3-limL was found to be most efficient, yielding a 67-fold greater production of active LipL than that obtained by the wild-type Pseudomonas sp. strain 109.