Akira Yamane

Development of high ductility and tensile properties by a two‐stage draw of poly(acrylonitrile): Effect of molecular weight

Ultradrawing of atactic poly(acrylonitrile) (PAN) was investigated for a Mv series, ranging 8.0 × 104–2.3 × 106. Samples for the draw were prepared from 0.5–30 wt % solutions of PAN in N,N′-dimethylformamide. The solutions were converted to a gel by quenching from 100 to 0°C. The dried gel films were initially drawn uniaxially by solid-state coextrusion (first-stage draw) to an extrusion draw ratio (EDR) of 16, followed by further tensile draw at 100–250°C (second-stage draw). The maximum total draw ratio (DRt,max) and tensile properties achieved by two-stage draw increased remarkably with sample Mv. Other factors affecting ductility were the solution concentration from which gel was made and the second-stage draw temperature. The effects of these variables became more prominent with increasing Mv. The temperature for optimum second-stage draw increased with sample Mv. Both the initial gel and the drawn products showed no small-angle X-ray long period scattering maximum, suggesting the absence of a chain-folded lamellae structure, which had been found in our previous study on the drawing of nascent PAN powder. The chain orientation function (fc) and sample density (ρs) increased rapidly with DRt in the lower range (DRt 30–100. The tensile modulus also showed a similar increase with DRt. The tensile strength increased linearly with DRt, reaching a maximum, and decreased slightly at yet higher DRt. The highest modulus of 28.5 GPa and strength of 1.6 GPa were achieved with the highest Mv of 2.3 × 106.

Epithelioid Cell Granuloma Detection in the Sputum of Patients with Pulmonary Tuberculosis

Background: Epithelioid cell granulomas (ECG) are evident in the histology of various pulmonary diseases, including pulmonary tuberculosis (PTB); however, the diagnostic value of ECG in sputum cytology for patients with granulomatous lung diseases is unclear. Methods: To evaluate the value of identifying ECG in the sputum of patients with PTB and other respiratory diseases, we retrospectively reviewed the cytology database and clinical profiles of patients admitted to our department between 2003 and 2011. Results: Of the 11,782 patients examined by sputum cytology, ECG was detected in the cytology specimens of 32 (0.3%) patients. Thirty-one of these patients had PTB, and the remaining patient had pulmonary nontuberculous mycobacteriosis (PNTM). There were no ECG-positive cases among patients with other respiratory diseases, with the exception of one patient with comorbid lung cancer and PTB. The incidence of ECG was significantly higher in PTB (0.8%, 31/3716 cases) than in PNTM (0.09%, 1/1117 cases, P>0.05). Langhans giant cells with (2 cases) and without (5 cases) necrosis was detected only in PTB specimens. Clinical findings in the PTB cases included cavities (68%) on radiography and positive sputum smear for acid-fast bacilli (90%); the PNTM case also showed cavity and smear-positive sputum. Conclusion: In our population of patients with various respiratory diseases, the existence of ECG in sputum cytology was rare and limited to pulmonary mycobacteriosis, particularly PTB. We suggest ECG detection is a useful aid for diagnosing unsuspected and infective PTB, and is associated with disease severity.

Relationship Between Lung Cancer and Mycobacterium Avium Complex Isolated Using Bronchoscopy

Introduction: The incidence of Mycobacterium avium complex (MAC)-positive respiratory specimen cultures and MAC lung disease (MACLD) is increasing worldwide. This retrospective study aimed to assess the association between MAC culture-positive bronchoscopy specimens and lung cancer. Materials and Methods: The medical records of 1382 untreated lung cancer patients between 2003 and 2011 were collected using our hospital database. Of them, records for 1258 that had undergone bronchoscopy together with sampling for mycobacterial culture were reviewed. Patient characteristics were compared between those with MAC-positive/other nontuberculous mycobacteria (NTM)-negative bronchial washings and those with MAC-negative/other NTM-negative bronchial washings. Patients with MAC-positive lung cancer were cross-sectionally divided into MACLD and non-MACLD groups, and their features were assessed. Follow-up data for patients with lung cancer but without MACLD were reviewed for subsequent development of MACLD. Results: Of the 1258 patients with lung cancer, 25 (2.0%) had MAC-positive/other NTM-negative bronchial washings. The proportion of women (52% vs 30%; P = 0.0274) and patient age (72 years vs 69 years; P = 0.0380) were significantly higher in the MAC-positive/other NTM-negative lung cancer group (n = 25) than in the MAC-negative/other NTM-negative lung cancer group (n = 1223). There were 10 patients with lung cancer and MACLD and 15 without MACLD; significant differences in patient characteristics were not found between the two groups, and none of the 15 patients without MACLD subsequently developed MACLD. Conclusion: MAC culture-positive bronchial washing is positively associated with lung cancer. Female sex and advanced age, but not lung cancer characteristics, were found to be associated with MAC infection in patients with lung cancer.

An HIV-positive Case of Obstructive Jaundice Caused by Immune Reconstitution Inflammatory Syndrome of Tuberculous Lymphadenitis Successfully Treated with Corticosteroids

A 60-year-old man was admitted to our hospital because of a persistent fever with enlargement of multiple lymph nodes in the mediastinum and around the pancreatic head. He was diagnosed with tuberculosis and human immunodeficiency virus infection. We started antiretroviral therapy three weeks after the initiation of anti-tuberculous therapy. Two weeks later, jaundice appeared with dilatation of the biliary tract due to further enlargement of the lymph nodes, which seemed to be immune reconstitution inflammatory syndrome (IRIS). The administration of corticosteroids resolved the obstructive jaundice without surgical treatment or endoscopic drainage. Obstructive jaundice caused by IRIS should first be treated with corticosteroids before invasive treatment.

Retrospective Study of Clinical Features and Prognosis of Pneumococcal Pneumonia Among Patients Under 65 Years of Age

The 23-valent pneumococcal polysaccharide vaccine (PPSV23) for elderly people has been included in the National Immunization Program (NIP) of Japan since October 2014. Targets for PPSV23 were restricted to persons ≥65 years of age and persons 60 to 64 years of age with an underlying severe physical disability (expressed as 1st grade in Japan). In this study, the clinical courses of non-target persons <65 years of age were compared between those with non-severe underlying diseases (A group) and those without underlying diseases (B group), and the need to expand the targets for PPSV23 within the NIP was investigated. Persons with pneumococcal pneumonia who were diagnosed based on a positive sputum or blood culture result were enrolled between January 2004 and April 2014. As a result, the number of subjects in A group was 2.6 times larger than that in B group, and this difference was especially pronounced (4.2 times) among subjects between the age of 60 to 64 years. These findings suggest that persons with underlying disease without a 1st grade physical disability might also be susceptible to pneumococcal pneumonia. No significant differences in the severity of pneumonia, the length of treatment, or the rates of admission were seen between A group and B group. The severity of pneumonia and the rates of admission among targets of the NIP were significantly higher than those of A group. In conclusion, our study suggests that A group should also be included among the targets of the NIP and that all targets eligible to receive the pneumococcal vaccine within NIP should be inoculated.