Masako Chiyo
Chiba University
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Featured researches published by Masako Chiyo.
Thorax | 2003
Kiyoshi Shibuya; H Hoshino; Masako Chiyo; Akira Iyoda; Shigetoshi Yoshida; Yasuo Sekine; Toshihiko Iizasa; Yukio Saitoh; Masayuki Baba; Kenzo Hiroshima; Hidemi Ohwada; Takehiko Fujisawa
Background: We investigated the use of high magnification bronchovideoscopy combined with narrow band imaging (NBI) for the detailed examination of angiogenic squamous dysplasia (ASD). This was carried out in relation to bronchial vascular patterns with abnormal mucosal fluorescence in heavy smokers at high risk for lung cancer. Methods: Forty eight patients with sputum cytology specimens suspicious or positive for malignancy were entered into the study. Conventional white light and fluorescence bronchoscopic examination was first performed. Observations by high magnification bronchovideoscopy with conventional white light were made primarily at sites of abnormal fluorescence, and then repeated with NBI light to examine microvascular networks in the bronchial mucosa. Spectral features on the RGB (Red/Green/Blue) sequential videoscope system were changed from the conventional RGB broadband filter to the new NBI filter. The wavelength ranges of the new NBI filter were B1: 400–430 nm, B2: 420–470 nm, and G: 560–590 nm. ASD tissues were also examined using a confocal laser scanning microscope equipped with argon-krypton (488 nm) and argon (514 nm) laser sources. Results: The microvessels, vascular networks of various grades, and dotted vessels in ASD tissues were clearly observed in NBI-B1 images. Diameters of the dotted vessels visible on NBI-B1 images agreed with the diameters of ASD capillary blood vessels diagnosed by pathological examination. Capillary blood vessels were also clearly visualised by green fluorescence by confocal laser scanning microscopy. There was a significant association between the frequency of dotted vessels by NBI-B1 imaging and tissues confirmed as ASD pathologically (p=0.002). Conclusions: High magnification bronchovideoscopy combined with NBI was useful in the detection of capillary blood vessels in ASD lesions at sites of abnormal fluorescence. This may enable the discrimination between ASD and another pre-invasive bronchial lesion.
American Journal of Transplantation | 2006
Shigetoshi Yoshida; Azizul Haque; Teruaki Mizobuchi; Takekazu Iwata; Masako Chiyo; Tonya J. Webb; L.A. Baldridge; Kathleen M. Heidler; Oscar W. Cummings; Takehiko Fujisawa; Janice S. Blum; David D. Brand; David S. Wilkes
Immunity to collagen V [col(V)] contributes to lung ‘rejection.’ We hypothesized that ischemia reperfusion injury (IRI) associated with lung transplantation unmasks antigenic col(V) such that fresh and well‐healed lung grafts have differential susceptibility to anti‐col(V)‐mediated injury; and expression of the autoimmune cytokines, IL‐17 and IL‐23, are associated with this process. Adoptive transfer of col(V)‐reactive lymphocytes to WKY rats induced grade 2 rejection in fresh isografts, but induced worse pathology (grade 3) when transferred to isograft recipients 30 days post‐transplantation. Immunhistochemistry detected col(V) in fresh and well‐healed isografts but not native lungs. Hen egg lysozyme‐reactive lymphocytes (HEL, control) did not induce lung disease in any group. Col(V), but not HEL, immunization induced transcripts for IL‐17 and IL‐23 (p19) in the cells utilized for adoptive transfer. Transcripts for IL‐17 were upregulated in fresh, but not well‐healed isografts after transfer of col(V)‐reactive cells. These data show that IRI predisposes to anti‐col(V)‐mediated pathology; col(V)‐reactive lymphocytes express IL‐17 and IL‐23; and anti‐col(V)‐mediated lung disease is associated with local expression of IL‐17. Finally, because of similar histologic patterns, the pathology of clinical rejection may reflect the activity of autoimmunity to col(V) and/or alloimmunity.
Chest | 2010
Taiki Fujiwara; Kazuhiro Yasufuku; Takahiro Nakajima; Masako Chiyo; Shigetoshi Yoshida; Makoto Suzuki; Kiyoshi Shibuya; Kenzo Hiroshima; Yukio Nakatani; Ichiro Yoshino
BACKGROUND Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure with a high yield for lymph node staging of lung cancer. The aim of this study was to assess the utility of sonographic features of lymph nodes during EBUS-TBNA for the prediction of metastasis in patients with lung cancer and to establish a standard endobronchial ultrasound (EBUS) image classification system. METHODS Digital images of lymph nodes obtained during EBUS-TBNA in patients with lung cancer were categorized according to the following characteristics: (1) size (short axis) less or more than 1 cm, (2) shape (oval or round), (3) margin (indistinct or distinct), (4) echogenicity (homogeneous or heterogeneous), (5) presence or absence of central hilar structure, and (6) presence or absence of coagulation necrosis sign. The sonographic findings were compared with the final pathologic results. RESULTS A total of 1,061 lymph nodes were retrospectively evaluated in 487 patients. The accuracy of predicting metastatic property for each category was as high as 63.8% to 86.0%. A multivariate analysis revealed that round shape, distinct margin, heterogeneous echogenicity, and presence of coagulation necrosis sign were independent predictive factors for metastasis. Two hundred eighty-five of the 664 lymph nodes (42.9%) having at least one metastatic feature of the four categories were pathologically proven metastatic, and 96.0% of lymph nodes (381/397) were proven not metastatic when all four categories were determined as benign. CONCLUSIONS Sonographic features of lymph nodes based on the new EBUS imaging classification may be helpful in the prediction of metastatic lymph nodes during EBUS-TBNA.
Respiratory Medicine | 2009
Takahiro Nakajima; Kazuhiro Yasufuku; Katsushi Kurosu; Yuichi Takiguchi; Taiki Fujiwara; Masako Chiyo; Kiyoshi Shibuya; Kenzo Hiroshima; Yukio Nakatani; Ichiro Yoshino
BACKGROUND The diagnosis of sarcoidosis requires both compatible clinical features and pathologic findings as a means to exclude other differential diagnoses. The utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for diagnosis of sarcoidosis has been reported, although its indication remains unclear for cases of suspicious sarcoidosis. To clarify the role of EBUS-TBNA for the diagnosis of sarcoidosis, we compared three diagnostic modalities: EBUS-TBNA, transbronchial lung biopsy (TBLB) and bronchoalveolar lavage fluid analysis (BAL). METHODS Thirty-eight patients with suspicious sarcoidosis who had enlarged hilar and/or mediastinal lymph nodes on chest CT were retrospectively reviewed. Patients with malignancies or prior established diagnosis of sarcoidosis were excluded. BAL was initially performed followed by TBLB and finally EBUS-TBNA at the same setting. Microbacterial examinations were also performed from all samples. RESULTS Pathological findings compatible with sarcoidosis were obtained in 32 patients. The remaining 6 patients were diagnosed as one case each of chronic eosinophilic pneumonia, atypical mycobacterial infection and tuberculosis, and the remaining three were pathologically indefinite cases. Clinically, 35 patients were diagnosed with sarcoidosis. The diagnostic accuracy of sarcoidosis was significantly better by EBUS-TBNA (91.4%, p<0.001) compared to the other two modalities. According to chest roentgenogram classifications, there were 31 stage I patients and 4 stage II patients. For stage I patients, EBUS-TBNA was significantly better (90.3%, p<0.001), but each modality showed 100% accuracy for stage II patients. CONCLUSION It is recommended that EBUS-TBNA is added to the conventional diagnostic modalities for patients with suspicious stage I sarcoidosis on chest roentgenogram.
International Journal of Cancer | 2005
Masako Chiyo; Osamu Shimozato; Ling Yu; Kiyoko Kawamura; Toshihiko Iizasa; Takehiko Fujisawa; Masatoshi Tagawa
A novel cytokine interleukin‐27 (IL‐27), composed of p28 and Epstein‐Barr virus‐induced gene 3 (EBI3), is produced from activated dendritic cells and is involved in an early phase of T‐helper type I differentiation. We examined whether Colon 26 murine colon carcinoma cells that were retrovirally transduced with the p28‐linked EBI3 gene (Colon 26/IL‐27) could produce antitumor effects in inoculated mice. Although proliferation in vitro of Colon 26/IL‐27 cells was not different from that of parent cells, syngeneic BALB/c mice rejected Colon 26/IL‐27 tumors inoculated and subsequently acquired tumor‐specific protective immunity. In contrast, mice inoculated with Colon 26 cells transduced with either the p28 or EBI3 gene developed tumors and survival of the mice remained the same as that of the mice inoculated with parent cells. Syngeneic nude mice developed Colon 26/IL‐27 tumors, but the growth was retarded compared to that of parent tumors. Depletion of natural killer cells from nude mice with anti‐asialo GM1 antibody diminished the growth retardation of Colon 26/IL‐27 tumors. Survival of severe combined immunodeficient mice that received subcutaneous inoculation of Colon 26/IL‐27 cells was not different from that of the immunodeficient mice inoculated with parent cells. Interferon‐γ was produced from CD4+ and CD8+ T, and natural killer cells of the mice that rejected Colon 26/IL‐27 tumors and cytotoxic activity against Colon 26 cells were also detected from the mice. These data collectively suggest that expressed IL‐27 in tumors produces T cell‐dependent and‐independent antitumor effects and is a possible therapeutic strategy for cancer. ©2005 Wiley‐Liss, Inc.
Thorax | 2002
Kiyoshi Shibuya; H Hoshino; Masako Chiyo; Kazuhiro Yasufuku; Toshihiko Iizasa; Yukio Saitoh; Masayuki Baba; Kenzo Hiroshima; Hidemi Ohwada; Takehiko Fujisawa
Background: We have developed a method of high magnification bronchovideoscopy that enables improved observation of subepithelial vascular patterns of the bronchial mucosa. A study was undertaken to investigate the value of high magnification bronchovideoscopy in the detailed examination of dysplasia in the bronchial mucosa of patients with abnormal mucosal fluorescence. Methods: Thirty one patients with sputum cytology specimens suspicious or positive for malignancy were entered into the study. Conventional white light examination was first performed under local anaesthesia and fluorescence bronchoscopy was also carried out using a light induced fluorescence endoscopy (LIFE) lung system. A high magnification bronchovideoscope (XBF 200HM2) was then used to examine the microvascular network in the bronchial mucosa at sites of normal and abnormal fluorescence and the images obtained were compared with pathological diagnoses from bronchial biopsy specimens. Vascular area ratios were calculated using image analysing apparatus. Results: Vascular networks with regular patterns were observed at 20 of 22 abnormal fluorescence sites in biopsy specimens from patients with bronchitis. However, vascular networks with increased vessel growth and complex networks of tortuous vessels of various sizes were observed in 15 of 21 abnormal fluorescence sites in dysplasia specimens. There was a significant difference between bronchitis and dysplasia specimens (OR=25, 95% CI 5.5 to 113, p<0.0001). Mean vascular area ratios from 16 normal bronchial epithelium specimens with normal fluorescence, and 22 bronchitis and 21 dysplasia specimens with abnormal fluorescence were 0.054 (95% CI 0.039 to 0.07), 0.095 (95% CI 0.072 to 0.118), and 0.173 (95% CI 0.143 to 0.203), respectively. The results indicate a statistically significant increase in vascular area in the three groups (p<0.0001). Conclusion: Areas of increased vessel growth and complex networks of tortuous vessels in the bronchial mucosa detected using a high magnification bronchovideoscope at sites of abnormal fluorescence may enable discrimination between bronchitis and dysplasia.
Journal of Immunology | 2008
Takekazu Iwata; Alexander Philipovskiy; Amanda J. Fisher; Robert G. Presson; Masako Chiyo; Jae Lee; Elizabeth A. Mickler; Gerald N. Smith; Irina Petrache; David B. Brand; William J. Burlingham; Bagavathi Gopalakrishnan; Daniel S. Greenspan; Jason D. Christie; David S. Wilkes
Primary graft dysfunction (PGD) is a major complication following lung transplantation. We reported that anti-type V collagen (col(V)) T cell immunity was strongly associated with PGD. However, the role of preformed anti-col(V) Abs and their potential target in PGD are unknown. Col(V) immune serum, purified IgG or B cells from col(V) immune rats were transferred to WKY rat lung isograft recipients followed by assessments of lung pathology, cytokines, and PaO2/FiO2, an index of lung dysfunction in PGD. Immune serum, purified IgG, and B cells all induced pathology consistent with PGD within 4 days posttransfer; up-regulated IFN-γ, TNF-α, and IL-1β locally; and induced significant reductions in PaO2/FiO2. Depleting anti-col(V) Abs before transfer demonstrated that IgG2c was a major subtype mediating injury. Confocal microscopy revealed strong apical col(V) expression on lung epithelial, but not endothelial cells; which was consistent with the ability of col(V) immune serum to induce complement-dependent cytotoxicity only in the epithelial cells. Examination of plasma from patients with or without PGD revealed that higher levels of preformed anti-col(V) Abs were strongly associated with PGD development. This study demonstrates a major role for anti-col(V) humoral immunity in PGD, and identifies the airway epithelium as a target in PGD.
The Journal of Thoracic and Cardiovascular Surgery | 2003
Masako Chiyo; Yasuo Sekine; Takekazu Iwata; Koichiro Tatsumi; Kazuhiro Yasufuku; Akira Iyoda; Mizuto Otsuji; Shigetoshi Yoshida; Kiyoshi Shibuya; Toshihiko Iizasa; Yukio Saitoh; Takehiko Fujisawa
BACKGROUND This study investigated postoperative morbidity, mortality, and the long-term survival for patients with lung cancer who have interstitial lung diseases. METHODS A retrospective chart review of 931 patients with lung cancer who underwent pulmonary resection at Chiba University Hospital between 1990 and 2000 was undertaken. Interstitial lung disease was defined by medical history, physical examination, and abnormalities compatible with bilateral lung fibrosis on chest computed tomography or high-resolution computed tomography (36 patients: 3.9%, interstitial lung diseases group). The remaining 895 patients (96.1%) were categorized as non-interstitial lung disease group. RESULTS The incidence of postoperative pneumonia and acute or exacerbation of interstitial pneumonia was higher in the interstitial lung disease group (all P <.05). Thirty-day mortality was statistically equivalent between the interstitial lung disease and the non-interstitial lung disease groups (P =.30). The 5-year overall survivals were 62.5% (non-interstitial lung disease) and 35.6% (interstitial lung disease). Respiratory failure was the second main cause of death after the recurrence of primary cancer in the interstitial lung disease group. The risk factors for long-term mortality were interstitial lung diseases, advanced pathologic stage, male sex, high age, and positive smoking history (all P <.05). CONCLUSIONS Interstitial lung disease was a risk factor for developing postoperative morbidity and mortality and poor long-term survival due to the occurrence of respiratory failure.
The Annals of Thoracic Surgery | 2003
Yasuo Sekine; Takekazu Iwata; Masako Chiyo; Kazuhiro Yasufuku; Shinichiro Motohashi; Shigetoshi Yoshida; Makoto Suzuki; Toshihiko Iizasa; Yukio Saitoh; Takehiko Fujisawa
BACKGROUND The aim of this study was to evaluate the influence of chronic obstructive pulmonary diseases (COPD) on postoperative pulmonary function and to elucidate the factors for decreasing the reduction of pulmonary function after lobectomy. METHODS We conducted a retrospective chart review of 521 patients who had undergone lobectomy for lung cancer at Chiba University Hospital between 1990 and 2000. Forty-eight patients were categorized as COPD, defined as percentage of predicted forced expiratory volume at 1 second (FEV1) less than or equal to 70% and percentage of FEV1 to forced vital capacity less than or equal to 70%. The remaining 473 patients were categorized as non-COPD. RESULTS Although all preoperative pulmonary function test data and arterial oxygen tension were significantly lower in the COPD group, postoperative arterial oxygen tension and FEV1 were equivalent between the two groups, and the ratio of actual postoperative to predicted postoperative FEV1 was significantly better in the COPD group (p < 0.001). With multivariable analysis, COPD and pulmonary resection of the lower portion of the lung (lower or middle-lower lobectomies) were identified as independent factors for the minimal deterioration of FEV1. Actual postoperative FEV1 was 15% lower and higher than predicted, respectively, in the non-COPD patients with upper portion lobectomy and the COPD patients with lower portion lobectomy. Finally, we created a new equation for predicting postoperative FEV1, and it produced a higher coefficient of determination (R(2)) than the conventional one. CONCLUSIONS The postoperative ventilatory function in patients with COPD who had lower or middle-lower lobectomies was better preserved than predicted.
Journal of Thoracic Oncology | 2007
Kazuhiro Yasufuku; Takahiro Nakajima; Masako Chiyo; Yasuo Sekine; Kiyoshi Shibuya; Takehiko Fujisawa
Endobronchial ultrasonography (EBUS) has emerged as a new diagnostic tool that allows the bronchoscopist to see beyond the airway. The radial probe EBUS was first introduced to evaluate the airway structure, which has been shown to be useful for identifying the extent of tumor invasion in the central airway. With advance in technology, smaller radial probes are now available that are capable of visualizing peripheral lung nodules. EBUS is also used as a tool to assist in a biopsy in respiratory diseases. The radial probe EBUS–guided transbronchial needle aspiration (TBNA) increases the yield of TBNA of mediastinal processes. By the use of the ultra-miniature probe EBUS along with the guide sheath, peripheral lung lesions can be accessed without the exposure to radiation. However, it is still not a real-time procedure with target visualization. The newest development is the convex probe EBUS (CP-EBUS) with a curvilinear electronic transducer on the tip of a flexible bronchovideoscope. CP-EBUS allows real-time EBUS-guided TBNA. Although the main indication for EBUS-TBNA is lymph node staging, it can also be used for diagnosis of intrapulmonary tumors, of unknown hilar and/or mediastinal lymphadenopathy, and of mediastinal tumors. To date, there are no reports of complications related to EBUS-guided TBNA. It is a novel approach that has a good diagnostic yield with excellent potential in assisting safe and accurate diagnostic interventional bronchoscopy. The aim of this review is to highlight the current status of the different EBUS techniques available and to discuss the future direction of EBUS.