Local order parameter that distinguishes crystalline and amorphous portions in polymer crystal lamellae.

The degradation of microplastics in relation to marine pollution has been receiving increasing attention. Because the spherulites that comprise microplastics have a highly ordered lamellar structure, their decomposition is thought to involve a lamellar structure collapse process. However, even in the simplest case of an order-disorder transition between lamellae and melt upon heating, the microscopic details of the transition have yet to be elucidated. In particular, it is unclear whether nucleation occurs at defects in the crystalline portion or at the interface between the crystalline and amorphous portions. To observe the transition in molecular simulations, an approach that distinguishes between the crystalline and amorphous structures that make up the lamella is needed. Local order parameters (LOPs) are an attempt to define the degree of order on a particle-by-particle basis and have demonstrated the ability to precisely render complex order structure transitions during phase transitions. In this study, 274 LOPs were considered to classify the crystalline and amorphous structures of polymers. Supervised machine learning was used to automatically and systematically search for the parameters. The identified optimal LOP does not require macroscopic information such as the overall orientation direction of the lamella layers but can precisely distinguish the crystalline and amorphous portions of the lamella layers using only a small amount of neighboring particle information.

Functional characterization of 21 CYP2C19 allelic variants for clopidogrel 2-oxidation.

Genetic variations in cytochrome P450 2C19 (CYP2C19) contribute to interindividual variability in the metabolism of therapeutic agents such as clopidogrel. Polymorphisms in CYP2C19 are associated with large interindividual variations in the therapeutic efficacy of clopidogrel. This study evaluated the in vitro oxidation of clopidogrel by 21 CYP2C19 variants harboring amino acid substitutions. These CYP2C19 variants were heterologously expressed in COS-7 cells, and the kinetic parameters of clopidogrel 2-oxidation were estimated. Among the 21 CYP2C19 variants, 12 (that is, CYP2C19.5A, CYP2C19.5B, CYP2C19.6, CYP2C19.8, CYP2C19.9, CYP2C19.10, CYP2C19.14, CYP2C19.16, CYP2C19.19, CYP2C19.22, CYP2C19.24 and CYP2C19.25) showed no or markedly low activity compared with the wild-type protein CYP2C19.1B. This comprehensive in vitro assessment provided insights into the specific metabolic activities of CYP2C19 proteins encoded by variant alleles, and this may to be valuable when interpreting the results of in vivo studies.

Functional characterization of 32 CYP2C9 allelic variants.

Genetic variations in cytochrome P450 2C9 (CYP2C9) contribute to interindividual variability in the metabolism of clinically used drugs such as warfarin and tolbutamide. We functionally characterized 32 types of allelic variant CYP2C9 proteins. Recombinant CYP2C9 proteins generated using a heterologous expression system are useful for comparing functional changes in CYP2C9 variant proteins expressed from low-frequency alleles. Wild-type CYP2C9 and its 31 variants were found to be transiently expressed in COS-7 cells, and the enzymatic activity of the CYP2C9 variants was characterized using S-warfarin as a representative substrate. Among the 32 types of CYP2C9 allelic variants tested, CYP2C9.18, CYP2C9.21, CYP2C9.24, CYP2C9.26, CYP2C9.33 and CYP2C9.35 exhibited no enzyme activity, and 12 types showed significantly decreased enzyme activity. In vitro analysis of CYP2C9 variant proteins should be useful for predicting CYP2C9 phenotypes and for application to personalized drug therapy.

Refined human artificial chromosome vectors for gene therapy and animal transgenesis.

Human artificial chromosomes (HACs) have several advantages as gene therapy vectors, including stable episomal maintenance, and the ability to carry large gene inserts. We previously developed HAC vectors from the normal human chromosomes using a chromosome engineering technique. However, endogenous genes were remained in these HACs, limiting their therapeutic applications. In this study, we refined a HAC vector without endogenous genes from human chromosome 21 in homologous recombination-proficient chicken DT40 cells. The HAC was physically characterized using a transformation-associated recombination (TAR) cloning strategy followed by sequencing of TAR-bacterial artificial chromosome clones. No endogenous genes were remained in the HAC. We demonstrated that any desired gene can be cloned into the HAC using the Cre-loxP system in Chinese hamster ovary cells, or a homologous recombination system in DT40 cells. The HAC can be efficiently transferred to other type of cells including mouse ES cells via microcell-mediated chromosome transfer. The transferred HAC was stably maintained in vitro and in vivo. Furthermore, tumor cells containing a HAC carrying the suicide gene, herpes simplex virus thymidine kinase (HSV-TK), were selectively killed by ganciclovir in vitro and in vivo. Thus, this novel HAC vector may be useful not only for gene and cell therapy, but also for animal transgenesis.

Thoracoscopic lobectomy with systemic lymph node dissection for lymph node positive non-small cell lung cancer--is thoracoscopic lymph node dissection feasible?

INTRODUCTION: The impact of thoracoscopic systemic lymph node dissection (LND) on loco-regional control of non-small cell lung cancer (NSCLC) with positive lymph node metastasis was investigated. PATIENTS AND METHODS: Thoracoscopic lobectomy with systemic LND was performed for clinical stage I NSCLC. 340 patients were admitted for either a thoracoscopic (n = 98) or a standard open (n = 242) lobectomy with systemic LND. Of those 340 cases, 75 cases (20 thoracoscopic and 55 open) were pathologically diagnosed with node-positive disease. A retrospective chart review of these 75 cases was performed. RESULTS: No significant difference in the overall or loco-regional recurrence-free survival was observed between the groups. The results of a multivariate analysis of the overall and the loco-regional recurrence-free survival demonstrated that the significant factors were tumor size for overall recurrence-free survival, and sex and surgical procedure (use of thoracoscopic surgery) for loco-regional recurrence-free survival, respectively. CONCLUSION: In general, thoracoscopic lobectomy for c-stage I disease may have no survival disadvantage over open procedures. It might, however, increase the risk of local recurrence when used to treat pathologically node-positive disease. Caution should be used when treating those cases with thoracoscopic surgery.

Comparison between a case-matched analysis of left upper lobe trisegmentectomy and left upper lobectomy for small size lung cancer located in the upper division.

BACKGROUND: Although an increasing number of approaches for pulmonary segmentectomy to treat early lung cancer are being used, there have been few reports on left upper lobe trisegmentectomy, which is midway between single segmentectomy and lobectomy, for lung cancer. METHODS: We retrospectively reviewed the medical charts of 86 clinical stage I case-matched patients with a tumor size of less than 2.0 cm in diameter located in the left upper division who underwent resection between June 1998 and December 2005. The patients were divided into two groups as follows: LTS (31), left upper lobe trisegmentectomy; LUL (55), left upper lobectomy. We evaluated these groups with respect to several factors. RESULTS: The characteristics of the two groups (LTS vs. LUL) demonstrated no significant differences with respect to gender, histological type, tumor size, or upstaging of pathological node, or the mode of video-assisted thoracic surgery (VATS). Patients with LTS had a significantly lower pulmonary function compared to the LUL group. There were no significant differences between the two groups with respect to factors such as blood loss and duration of chest tube drainage. Morbidity and recurrence rates did not differ between the two groups, and there was no mortality in our series. The overall survival rate at 5 years was 69.7 % in the LTS and 72.5 % in the LUL group. There was no significant difference in survival rates between the LTS and the LUL group after resection. CONCLUSION: LTS may be suitable as a standard treatment if the tumor is small and the suspected margins are well away from the lingula.

[Successful treatment for descending necrotizing mediastinitis; report of a case].

A case of a 55-year-old man with descending necrotizing mediastinitis (DNM) after a tooth removal was reported. Chest computed tomography (CT) showed a fluid collection in the right thorax, in the cervical region and in the mediastinum. The patient underwent cervical drainage and thoracoscopic pleural dissective drainage. The cervical and right anterior thoracic drain was removed on the 6th day and posterior drain was removed on the 8th day after the operation. The patient was discharged on the postoperative day 13, and showed no recurrence.

SIRT2, a tubulin deacetylase, acts to block the entry to chromosome condensation in response to mitotic stress.

We previously identified SIRT2, an nicotinamide adenine dinucleotide (NAD)-dependent tubulin deacetylase, as a protein downregulated in gliomas and glioma cell lines, which are characterized by aneuploidy. Other studies reported SIRT2 to be involved in mitotic progression in the normal cell cycle. We herein investigated whether SIRT2 functions in the mitotic checkpoint in response to mitotic stress caused by microtubule poisons. By monitoring chromosome condensation, the exogenously expressed SIRT2 was found to block the entry to chromosome condensation and subsequent hyperploid cell formation in glioma cell lines with a persistence of the cyclin B/cdc2 activity in response to mitotic stress. SIRT2 is thus a novel mitotic checkpoint protein that functions in the early metaphase to prevent chromosomal instability (CIN), characteristics previously reported for the CHFR protein. We further found that histone deacetylation, but not the aberrant DNA methylation of SIRT2 5'untranslated region is involved in the downregulation of SIRT2. Although SIRT2 is normally exclusively located in the cytoplasm, the rapid accumulation of SIRT2 in the nucleus was observed after treatment with a nuclear export inhibitor, leptomycin B and ionizing radiation in normal human fibroblasts, suggesting that nucleo-cytoplasmic shuttling regulates the SIRT2 function. Collectively, our results suggest that the further study of SIRT2 may thus provide new insights into the relationships among CIN, epigenetic regulation and tumorigenesis.

[Clinical features of thoracic injury; special reference to diaphragmatic injury].

UNLABELLED: We investigated the clinical feature of thoracic injury patients, mainly with diaphragmatic injury. From 1993 to 2005, 739 patients with thoracic injury were treated at our life-saving emergency center. There were more blunt trauma patients than penetrating injury patients (693 cases vs 46 cases). Regarding the thoracic injury patients, the causes of trauma were traffic injury in 462 (62.5%), unexpected accident including work place accident in 153 (20.7%), suicide in 90 (12.2%), and assault in 34 (4.6%). As the numbers of injured organs increased, the mortality rate increased. Among 156 patients with cardiopulmonary arrest on admission, 155 patients died. This result suggested that saving the life of patients presenting with cardiopulmonary arrest on admission is extremely difficult. Thirty-eight cases (5.1%) required surgical treatment, and surgery to repair diaphragmatic injury was performed in 14 cases. In 6 cases of diaphragmatic injury, thoracoscopy was performed during the examination and/or surgery. CONCLUSION: Urgently transporting thoracic injury patients to hospital before the onset of cardiopulmonary arrest is therefore essential in order to reduce the mortality rate of these patients. In addition, thoracoscopy is very useful for both examining and treating traumatic diaphragmatic injury patients.

Genetic variation in ABCB1 influences paclitaxel pharmacokinetics in Japanese patients with ovarian cancer.

Paclitaxel, an antineoplastic agent used for the treatment of ovarian cancer, is metabolized by cytochrome P450 (CYP)3A4 and CYP2C8 and is excreted from cells by ATP-binding cassette (ABCB1) (multi-drug resistance [MDR1], P-glycoprotein). Expression of these proteins is regulated by pregnane X receptor (PXR). Although there are common genetic polymorphisms in the genes encoding these proteins, their effect on the clinical efficacy of paclitaxel is unclear. We therefore examined the relationship of the paclitaxel pharmacokinetics in 13 patients with ovarian cancer to polymorphisms in CYP2C8, CYP3A5, ABCB1, and PXR. We found high interindividual variability in the plasma concentrations of two metabolites, 6alpha-hydroxypaclitaxel and p-3'-hydroxypaclitaxel. All the patients were genotyped as CYP2C8*1/*1. Neither the CYP3A5 A6986G (CYP3A5*3) nor the PXR C-25385T alleles were associated with altered plasma concentrations of paclitaxel and its metabolites. ABCB1 T-129C, T1236C, and G2677(A,T), however, was associated with lower area under the plasma concentration-time curve (AUC) of paclitaxel. We also observed a significant correlation between the AUC (r=-0.721) or the total clearance of paclitaxel (CL(tot)) (r= 0.673) and the ABCB1 mutant allele dosage in each patient. Taken together, our findings suggest that interindividual variability in paclitaxel pharmacokinetics could be predicted by ABCB1 genotyping.

A completely thoracoscopic lobectomy/segmentectomy for primary lung cancer--technique, feasibility, and advantages.

INTRODUCTION: A completely thoracoscopic lobectomy/segmentectomy for primary lung cancer was designed to maximize the benefits of this type of minimally invasive surgery. The technique, feasibility, and advantages of this surgical modality over the conventional procedure were investigated. MATERIALS AND METHODS: Between January 2003 and December 2004, 38 patients underwent a lobectomy (n = 30) or segmentectomy (n = 8) for clinical stage IA primary lung cancer. A resection using a standard thoracotomy (Thoracotomy Group) was performed in 19 patients, and a completely thoracoscopic resection was performed in 10 cases (CTR Group). Conventional video-assisted thoracic surgery with a mini-thoracotomy was performed in 9 cases. RESULTS: All CTR lobectomies or segmentectomies were carried out safely without any major complications. The number of resected mediastinal lymph nodes was similar in both groups. There was a tendency for the hospital stay to be somewhat shorter in the CTR Group. With respect to postoperative pain as evaluated by a visual analogue scale (VAS), the CTR Group showed a significantly lower level of pain in comparison to the Thoracotomy Group ( P = 0.024 on day 2). CONCLUSIONS: We concluded that a complete thoracoscopic lung resection is a safe and technically feasible surgical procedure which enables us to make thoracoscopic lung resections less invasive.

Prognostic significance of subcarinal station in non-small cell lung cancer with T1-3 N2 disease.

BACKGROUND: Surgical resection may continue to offer the best chance of long-term survival for patients with non-small cell lung cancer (NSCLC). Generally, patients with N2 NSCLC have a poor prognosis. However, the surgical treatment of patients with N2 remains controversial as in these patients, some N2 subgroups have better prognoses than others. The objective of the current study was to evaluate the factors associated with N2, and to determine whether such factors are reliable predictors of survival. METHODS: We retrospectively reviewed 142 non-small cell lung cancer patients with T1-3 N2 in whom a curative approach had been attempted between January 1994 and December 2003. The patients were consequently divided into four groups (NS-1, no subcarinal involvement and without N1; NS-2, no subcarinal involvement and with N1; SI-1, subcarinal involvement and without upper mediastinal site; SI-2, subcarinal involvement and with upper mediastinal site). We also evaluated two groups for N2 stations (single-station N2 versus multiple-station N2). Multivariate analysis by Cox's proportional hazards regression model was performed to identify the prognosis. RESULTS: Lobectomy was carried out in 105 of the patients; bilobectomy in 10, and pneumonectomy in 27. The patients with T1-3 N2 disease showed survival rates of 34.1 % at 3 years and 24.1 % at 5 years. The overall survival rates at 3 years and 5 years were as follows: NS-1, 56.3 % and 43.2 %; NS-2, 35.4 % and 29.5 %; SI-1, 16.7 % and 0 %; SI-2, 15.4 % and 0 %, respectively. The NS-1 group had better prognoses than the other groups. There was a significant difference in survival rates within each group ( p = 0.0005). In univariate analysis, the type of surgery, type of subcarinal involvement, and multiple-station N2 were significantly associated with prognosis. Multivariate analysis showed that NS-1 was only found to be an independent prognostic factor in cases of T1-3 N2 disease ( p = 0.0018). NS-2 was not an independent factor but tended toward significance ( p = 0.0681). But multiple-station N2 was not an independent factor ( p = 0.1549). CONCLUSIONS: Surgery for patients with T1-3 N2 NSCLC might be acceptable if subcarinal lymph node metastasis is predicted to be absent.

Extended resection of T4 lung cancer with invasion of the aorta: is it justified?

BACKGROUND: We report our 10-year experience of performing surgical resection of T4 lung cancer invading the thoracic aorta. PATIENTS AND METHODS: From 1994 to 2004, sixteen patients with T4 primary lung cancer with local invasion of the thoracic aorta underwent tumor resection. Surgical resection included 8 pneumonectomies and 8 lobectomies. The histologic type was squamous cell carcinoma in 7 patients, adenocarcinoma in 7, large cell carcinoma in 1, and small cell carcinoma in 1. Complete resection of the tumor with mediastinal lymph node dissection was achieved in 8 patients (50 %), while the resection was incomplete in the other 8 cases. RESULTS: The overall cumulative survival of the 16 patients at 3 and 5 years was 34.7 % and 17.4 %, respectively. The survival of the patients in the complete resection group was found to be 36.5 % at 5 years, with 2 patients surviving more than 5 years without a recurrence, which was significantly better than that of the incomplete resection group ( p = 0.005). CONCLUSIONS: Extended aortic resection with primary lung cancer is complex and possibly high risk, but can achieve long-term survival in selected patients. Surgical resection should be considered as a treatment option for T4 lung cancer for this T4 subcategory.

Penetration to the aortic wall by a metallic airway stent. A successfully treated case with left pneumonectomy and aortic repair.

Metallic airway stents were used widely at the beginning of airway stent use, but an accumulation of cases has revealed complications due to their use. A patient who received a Gianturco Z stent for bronchial tuberculosis suffered massive haemoptysis due to stent migration into the aortic wall. Left pneumonectomy with aortic repair was successfully performed. We suggest that metallic stents should not be used for benign airway palliation, as they may later cause life-threatening complications.

[Treatment strategy for patients, with locally advanced non-small cell lung cancer].

A total of 89 patients with locally advanced lung cancer (pT3-4N0-1) underwent pulmonary resection from April 1994 to April 2003 at our institutions. The overall 5-year survival rate of the 89 patients was 35.5%. No significant difference in the 5-year survival rate was found according to the following variables: histologic type, type of operation, number of resected organs, performance of adjuvant therapy and pulmonary function. In patients with pN1 disease, when patients with nodal metastasis were divided into patients with hilar (# 10) or lobar (# 11 approximately 13) metastasis, the survival rate of lobar metastasis group was superior to those of hilar metastasis group, but not significantly. In patients with pN1 disease, 5 patients were survived for more than 1,000 days. The histology was squamous cell carcinoma in 4 cases. According to the characteristics of pN1 involvement, all cases was involved only a single station.

[Primary pulmonary meningioma; report of a case].

Primary pulmonary meningiomas are quite rare, and their occurrence has been reported only sporadically. A 49-year-old, asymptomatic female was hospitalized for the evaluation of a coin lesion in the left lung radiography. She has no history of previous neoplasm or symptom referable to the central nervous system. Chest computed tomography (CT) demonstrated a 9 x 14 mm, round, noncalcified, well-demarcated lesion in the left upper lobe of the lung (S(1+2)). For diagnostic purposes, enucleation of the tumor was performed. The resected specimen revealed histologically classical typical meningioma. Because postoperative magnetic resonance imaging (MRI) of the brain did not show any intracranial mass, this case was and diagnosed as a primary pulmonary meningioma. The patient was discharged with no complication, and alive without recurrence of disease 14 months after surgery.

[Diaphragmatic eventration resulting from phrenicectomy treated with surgical method; report of a case].

The case was a 59-year-old man who has a history of left mediastinal tumor resection with left phrenicectomy. The elevated diaphragm revealed by chest X-ray 7 years after the operation led to diagnosis of diaphragmatic eventration. Since any symptom was seen in the early period, "wait and watch" strategy was done for management. Both the abdominal enlarged feeling and the dyspnea on effort were appeared 10 years after the operation. Under the speculation of these symptoms related to the elevated abdominal organs came up with diaphragmatic eventration, surgical method the plication of the diaphragm was performed. The diaphragm was plicated by interrupted suture as opening the diaphragm to avoid injury the abdominal organs, and reinforced with the Marlex mesh. We used artificial mesh to reinforce the thin diaphragm with exceptation of prevent the postoperative recurrence, because a result of the etiological process of the case was considered as disuse atrophy of diaphragm after phrenicectomy.

Human artificial chromosome (HAC) vector provides long-term therapeutic transgene expression in normal human primary fibroblasts.

Human artificial chromosomes (HACs) segregating freely from host chromosomes are potentially useful to ensure both safety and duration of gene expression in therapeutic gene delivery. However, low transfer efficiency of intact HACs to the cells has hampered the studies using normal human primary cells, the major targets for ex vivo gene therapy. To elucidate the potential of HACs to be vectors for gene therapy, we studied the introduction of the HAC vector, which is reduced in size and devoid of most expressed genes, into normal primary human fibroblasts (hPFs) with microcell-mediated chromosome transfer (MMCT). We demonstrated the generation of cytogenetically normal hPFs harboring the structurally defined and extra HAC vector. This introduced HAC vector was retained stably in hPFs without translocation of the HAC on host chromosomes. We also achieved the long-term production of human erythropoietin for at least 12 weeks in them. These results revealed the ability of HACs as novel options to circumvent issues of conventional vectors for gene therapy.

Mediastinal solitary fibrous tumor: report of a case with direct invasion to the trachea.

The solitary fibrous tumors in the pleura are a rare entity that is usually adhesive and sometimes invasive. Because of its benign feature, complete surgical resection is generally considered. We describe a very rare case of mediastinal solitary fibrous tumor arised or invaded into the tracheal wall, which was surgically resected with combined cylindrical resection of the trachea.