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81.
Takaaki Imamura Osamu Yokosuka Tetsuhiro Chiba Tatso Kanda Hiroshige Kojima Kenichi Fukai Fumio Imazeki Miki Nishimura Yasushi Saito Hiromitsu Saisho 《Leukemia & lymphoma》2005,46(6):915-917
We report the case of a 52-year-old woman with hepatitis B virus (HBV) reactivation during treatment for chronic graft vs. host disease (GVHD) after peripheral bone marrow transplantation (PBSCT) to treat chronic myelocytic leukemia. She was given cyclosporine and prednisolone orally to treat chronic GVHD after PBSCT. Liver dysfunction first developed 25 months after transplantation with the appearance of hepatitis B s antigen (HBsAg), hepatitis B e antigen (HBeAg), and elevation of HBV-DNA up to 4.5 log copies/ml. Retrospective examination of her serum before PBSCT proved negative for HBsAg and HBeAg, and positive for anti-HBsAg, anti-HBeAg, anti-hepatitis B core antigen, and HBV-DNA (2.7 log copies/ml), showing that she was in a state of occult HBV infection. Nucleotide sequences of the HBV genome obtained from her serum showed no core promoter mutations at nt 1762 and 1764 and no pre-core mutation at nt 1896. Polymerase chain reaction-restriction fragment length polymorphism showed that she was infected with HBV genotype B. The administration of lamivudine, a nucleoside analog, improved her liver function and reduced HBV-DNA replication. We conclude that antiviral agents, such as lamivudine, are effective for treating hepatitis B reactivation during immunosuppressive treatment, such as for GVHD. The administration of a nucleoside analog before transplantation should also be considered in the light of HBV genotypes and mutations, even if HBsAg was negative and the viral load was low before transplantation. 相似文献
82.
Ishige I Eishi Y Takemura T Kobayashi I Nakata K Tanaka I Nagaoka S Iwai K Watanabe K Takizawa T Koike M 《Sarcoidosis, vasculitis, and diffuse lung diseases : official journal of WASOG / World Association of Sarcoidosis and Other Granulomatous Disorders》2005,22(1):33-42
BACKGROUND: In studies of the unknown etiology of sarcoidosis, Propionibacterium acnes (a possible agent) was found in the lungs and lymph nodes of many sarcoidosis patients and some control subjects. P. acnes might be commensal not only to the skin, conjunctivae, and intestine, but also to the lungs and lymph nodes of individuals without sarcoidosis. METHODS: We cultured peripheral lung tissue and various lymph nodes obtained from patients with diseases other than sarcoidosis. DNA of 45 isolates of P. acnes from these patients, 67 isolates from normal skin, conjunctiva, and intestine, and 39 isolates from sarcoid lymph nodes were compared by random amplified polymorphic DNA analysis. RESULTS: P. acnes was isolated from half of 43 lungs and 8 of 11 mediastinal lymph nodes, mostly in pure culture. P. acnes was isolated from half of 20 gastric and 3 of 12 intestinal lymph nodes; intestinal bacteria were also numerous. In general, fewer than 500 colony-forming units of P. acnes per gram tissue were isolated, but 4 lung tissue specimens, 2 of which had a few granulomas, had many more. P. acnes strains from a particular site (lung, lymph node, skin or conjunctivae, and intestine) were genetically similar, more than isolates obtained from different sites. Lymph-node isolates from subjects with and without sarcoidosis differed little. CONCLUSION: These results suggest that P. acnes normally resides in peripheral lung tissue and mediastinal lymph nodes and that the strains of P. acnes isolated from sarcoid lymph nodes were not specific to sarcoidosis. 相似文献
83.
Fukumoto A Kim YP Matsumoto A Takahashi Y Shiomi K Tomoda H Omura S 《The Journal of antibiotics》2008,61(1):1-6
Cyslabdan, a new potentiator of imipenem activity against methicillin-resistant Staphylococcus aureus, was isolated from the culture broth of Streptomyces sp. K04-0144 by Diaion HP-20 and ODS column chromatographies and preparative HPLC. The structure of cyslabdan was elucidated by spectroscopic analyses including NMR. The compound has a labdane-type diterpene skeleton connecting with an N-acetylcysteine via thioether linkage. 相似文献
84.
85.
Shigeharu Ohyu Mitsuhiro Tozaki Michiro Sasaki Hisae Chiba Qilin Xiao Yasuko Fujisawa Yoshiaki Sagara 《Magnetic resonance in medical sciences》2022,21(3):485
Purpose: We evaluated the diagnostic performance of the texture features of dynamic contrast-enhanced (DCE) MRI for breast cancer diagnosis in which the discriminator was optimized, so that the specificity was maximized via the restriction of the negative predictive value (NPV) to greater than 98%.Methods: Histologically proven benign and malignant mass lesions of DCE MRI were enrolled retrospectively. Training and testing sets consist of 166 masses (49 benign, 117 malignant) and 50 masses (15 benign, 35 malignant), respectively. Lesions were classified via MRI review by a radiologist into 4 shape types: smooth (S-type, 34 masses in training set and 8 masses in testing set), irregular without rim-enhancement (I-type, 60 in training and 14 in testing), irregular with rim-enhancement (R-type, 56 in training and 22 in testing), and spicula (16 in training and 6 in testing). Spicula were immediately classified as malignant. For the remaining masses, 298 texture features were calculated using a parametric map of DCE MRI in 3D mass regions. Masses were classified into malignant or benign using two thresholds on a feature pair. On the training set, several feature pairs and their thresholds were selected and optimized for each mass shape type to maximize specificity with the restriction of NPV > 98%. NPV and specificity were computed using the testing set by comparison with histopathologic results and averaged on the selected feature pairs.Results: In the training set, 27, 12, and 15 texture feature pairs are selected for S-type, I-type, and R-type masses, respectively, and thresholds are determined. In the testing set, average NPV and specificity using the selected texture features were 99.0% and 45.2%, respectively, compared to the NPV (85.7%) and specificity (40.0%) in visually assessed MRI category-based diagnosis.Conclusion: We, therefore, suggest that the NPV of our texture-based features method described performs similarly to or greater than the NPV of the MRI category-based diagnosis. 相似文献
86.
Koichi Ito Emiko Chiba Noriko Oyama-Manabe Satoshi Washino Osamu Manabe Tomoaki Miyagawa Kohei Hamamoto Masahiro Hiruta Keisuke Tanno Hiroshi Shinmoto 《Magnetic resonance in medical sciences》2022,21(3):477
Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm2) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10–3 mm2/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA. 相似文献
87.
Hikaru Iwashita Yukihisa Matsumoto Yusuke Maruyama Kazuki Watanabe Atsuhiko Chiba Atsuhiko Hattori 《Journal of pineal research》2021,70(1):e12703
Melatonin (MEL) has been reported to enhance cognitive processes, making it a potential treatment for cognitive decline. However, the role of MEL’s metabolites, N1‐acetyl‐N2‐formyl‐5‐methoxykynuramine (AFMK) and N1‐acetyl‐5‐methoxykynuramine (AMK), in these effects are unknown. The current study directly investigated the acute effects of systemic MEL, AFMK, and AMK on novel object recognition. We also analyzed MEL, AFMK, and AMK levels in hippocampus and temporal lobe containing the perirhinal cortex following systemic MEL and AMK treatment. AMK administered post‐training had a more potent effect on object memory than MEL and AFMK. AMK was also able to rescue age‐associated declines in memory impairments when object memory was tested up to 4 days following training. Results from administering AMK at varying times around the training trial and the metabolism time course in brain tissue suggest that AMK’s memory‐enhancing effects reflect memory consolidation. Furthermore, inhibiting the MEL‐to‐AMK metabolic pathway disrupted object memory at 24 hours post‐training, suggesting that endogenous AMK might play an important role in long‐term memory formation. This is the first study to report that AMK facilitates long‐term object memory performance in mice, and that MEL crosses the blood‐brain barrier and is immediately converted to AMK in brain tissue. Overall, these results support AMK as a potential therapeutic agent to improve or prevent memory decline. 相似文献
88.
Xiaoyi Jin Tomoyuki Koike Takashi Chiba Yutaka Kondo Nobuyuki Ara Kaname Uno Naoki Asano Katsunori Iijima Akira Imatani Mika Watanabe Akio Shirane Tooru Shimosegawa 《Digestive endoscopy》2013,25(5):547-549
In the present paper, we report a case of rare collagenous gastritis. The patient was a 25‐year‐old man who had experienced nausea, abdominal distention and epigastralgia since 2005. Esophagogastroduodenoscopy (EGD) carried out at initial examination by the patient's local doctor revealed an extensively discolored depression from the upper gastric body to the lower gastric body, mainly including the greater curvature, accompanied by residual mucosa with multiple islands and nodularity with a cobblestone appearance. Initial biopsies sampled from the nodules and accompanying atrophic mucosa were diagnosed as chronic gastritis. In August, 2011, the patient was referred to Tohoku University Hospital for observation and treatment. EGD at our hospital showed the same findings as those by the patient's local doctor. Pathological findings included a membranous collagen band in the superficial layer area of the gastric mucosa, which led to a diagnosis of collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic findings to make a diagnosis. 相似文献
89.
90.
Go Inokuchi Daisuke Yajima Mustumi Hayakawa Ayumi Motomura Fumiko Chiba Yohsuke Makino Hirotaro Iwase 《International journal of legal medicine》2013,127(1):263-266
The issue of proper use of postmortem computed tomography (PMCT) in forensic fields is currently being actively discussed. The PMCT image has specific findings that differ from the antemortem image, and it is essential to understand and interpret postmortem changes in order to utilize PMCT properly. In this article, we present two cases of acute subdural hematoma (ASDH) in which images were obtained both ante- and postmortem. These images showed marked reduction of hematoma and diminishing midline shift between the agonal and postmortem periods, without evacuation of the hematoma. Attention should be paid to this phenomenon because key findings in determining cause of death could disappear if investigating the cause of death takes too long in cases that prove to be ASDH. In other words, this phenomenon potentially becomes a risk for misdiagnosis when we decide the cause of death without knowing the details of the circumstances of death. 相似文献