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Low-Dose Rate Brachytherapy with I-125 Seeds as a Monotherapy for High-Risk Prostate Cancer Patient: A Japanese Single Institutional Study. Int J Radiat Oncol Biol Phys 2017. [DOI: 10.1016/j.ijrobp.2017.06.1191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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SU-F-T-332: Dose Impact of Rectal Gas On Prostate VMAT. Med Phys 2016. [DOI: 10.1118/1.4956517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Contribution of Imaging in Diagnosis of Local Recurrence After Radiation Therapy for Cervical Cancer. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.1492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Treatment Effect of Neoadjuvant Chemoradiation Therapy for Non-small Cell Lung Cancer Evaluated by Multimodality Imaging and Histopathological Analyses. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.1535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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EP-1224 USEFULNESS OF DIAGNOSTIC IMAGING IN NEOADJUVANT CHEMO-RADIATION THERAPY FOR NON-SMALL CELL LUNG CANCER. Radiother Oncol 2012. [DOI: 10.1016/s0167-8140(12)71557-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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SU-E-T-484: Impact of Multileaf Collimator Leaf Positioning Accuracy on Intensity Modulated Radiation Therapy. Med Phys 2011. [DOI: 10.1118/1.3612437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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O34. TGF-β signaling maintains tumorigenicity of glioma-initiating cells through the Sox4–Sox2 axis. Differentiation 2010. [DOI: 10.1016/j.diff.2010.09.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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The incidence and the mechanism of sunitinib-induced thyroid atrophy in patients with metastatic renal cell carcinoma. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e15097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Efficacy and thyroidal effects of sunitinib in Japanese patients with metastatic renal cell carcinoma: Hypothyroidism and thyroid atrophy as potential biomarkers for sunitinib? J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.e16097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e16097 Background: Although hypothyroidism is a well-known adverse effect of sunitinib in western patients (pts) with metastatic renal cell carcinoma (MRCC), the effects on thyroid gland of sunitinib in Japanese pts still remain unclear. We therefore evaluated thyroid dysfunction and thyroid atrophy in Japanese RCC pts who received sunitinib. Methods: Fourteen (8 males, 6 females) of 51 pts who were treated in a phase II trial of sunitinib in Japanese pts with MRCC were included in this retrospective study. All 14 pts were euthyroid at baseline. The measurement of serum thyroid function test (fT3, fT4, TSH) was performed at the beginning of each sunitinib treatment cycle. A TSH concentration greater than 10 mU/L was considered as hypothyroidism regardless of subclinical or clinical. CT volumetry of the thyroid gland was performed utilizing the data obtained for tumor assessment in a phase II trial. Tumor response was evaluated based on the RECIST criteria. Results: 9 (64%) of 14 pts achieved RECIST-defined objective response (1 CR, 8 PRs). With regard to thyroid function, hypothyroidism was experienced by 11 (79%) pts. Three of 11 pts had Sunitinib-induced thyrotoxicosis before experiencing hypothyroidism. The mean time to development of hypothyroidism was 55 days (range 13–668). Six pts received typical doses of L-thyroxine. The response rate was 73% (8/11) in pts with hypothyroidism and 33% (1/3) in pts without. With regard to the volume of thyroid gland in 13 pts, 8 pts had more than 50% reduction comparing the volume at the baseline. Median reduction rate in volume of 13 pts was 57% (range 0–95%). Hypothyroidism was experienced by all 8 pts with more than 50% reduction in volume and 2 of 5 (40%) without. Furthermore, the response rate was 88% (7/8) in former pts and 40% (2/5) in latter pts. Conclusions: In addition to high anti-tumor efficacy, hypothyroidism and thyroid atrophy were commonly observed in Japanese MRCC pts who received sunitinib. Although further study should be required, these abnormal findings in thyroid gland following treatment with sunitinib may be potential biomarkers for tumor response to sunitinib. [Table: see text]
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Predictive Value of 18F-fluorodeoxyglucose Uptake by Positron Emission Tomography for Non-small Cell Lung Cancer Patients Treated with Radical Radiotherapy Requires Consideration of Primary Tumor Size. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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SU-GG-J-132: Motion Characterization for Early Stage Non-Small Cell Lung Cancer. Med Phys 2008. [DOI: 10.1118/1.2961681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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TU-C-351-05: Daily Alignment Results for In-Room CT-Guided Stereotactic Body Radiation Therapy for Lung Cancer. Med Phys 2008. [DOI: 10.1118/1.2962468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Long-term Results of Radiation Therapy in Elderly Patients With Cervical Cancer. Int J Radiat Oncol Biol Phys 2007. [DOI: 10.1016/j.ijrobp.2007.07.1536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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[Quality control (QC) of CT on rail system (FOCAL Unit) with a micro-multi leaf collimator (mMLC) using new GafChromic film for stereotactic radiotherapy]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2006; 62:711-3. [PMID: 16770852 DOI: 10.6009/jjrt.62.711] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE Recent years, CT on rail system was reported to be useful as a tool for image-guided radiotherapy (IGRT). This system was clinically developed with the aim of stereotactic irradiation (STI) for brain, lung, liver, prostate and other sites. Quality assurance and quality control (QC) is an important issue in CT on rail system to assure geometric accuracies. The purpose of this study is to estimate the geometric accuracies of our CT on rail system using a detachable micro-multi leaf collimator (mMLC) with new type radiochromic films. Carrying out our original QC program, translational errors, setup reproducibility, beam misalignment and beam characteristics were evaluated. METHODS AND MATERIALS We have studied with CT on rail system (FOCAL unit, Toshiba Medical systems, Tokyo, Japan) and mMLC unit (Accuknife, Direx Inc., Tokyo, Japan). We have developed original alignment phantom and small steel markers (2 mm phi) were implanted on its surface at certain intervals. Firstly, we have evaluated the accuracy of self-moving CT gantry and CT resolutions for cranio-caudal directions by changing slice thickness. And then using the phantom, we have measured the accuracy and reproducibility of geometric isocenter of the linac side and the CT gantry side by scanning the phantom. We have also measured the geometric changes of the common treatment couch by weight-loaded test (up to 135 kgw). To estimate dosimetric and geometric accuracies with the mMLC unit, the misalignment of the beam axes (gantry, collimator and couch rotation axis), mMLC leaf positions, and dose distributions for the verification plan were measured with new type GafChromic films (GafChromic-RTQA, ISP Inc., USA) and cylindrical phantom. The dose characteristics of the GafChromic film were also evaluated. RESULTS The reproducibility of the self-moving CT gantry have a good agreement within 1 mm. Weight-load test have shown a good reliability within 2 mm at the common treatment couch. The translational precision of the common treatment couch was 0.0 +/- 0.1 mm at linac side and -0.2 +/- 0.5 mm at CT gantry side. The misalignments of beam axes have been kept within 0.4 mm at maximum. Gap test have shown the accuracies of the mMLC leaf positions, which is needed to keep within 1 mm by a routine calibration. CONCLUSIONS To practice quality control program for the FOCAL unit and the mMLC unit is essential for a regular interval to reduce systematic errors. New type radiochromic film would be useful for a verification tool as alternative to conventional film.
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536 Quality control of CT on rail system (FOCAL unit) with a micro-multi leaf collimator (mMLC) using new Gafchromic film for stereotactic radiotherapy. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)81512-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Fractionated stereotactic radiotherapy of brain metastases from renal cell carcinoma. Int J Radiat Oncol Biol Phys 2000; 48:1389-93. [PMID: 11121638 DOI: 10.1016/s0360-3016(00)00804-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) for brain metastases from renal cell carcinoma (RCC). METHODS AND MATERIALS From May 1983 to September 1998, 35 patients with brain metastases from RCC underwent radiotherapy at the National Cancer Center Hospital, Tokyo; 10 patients treated initially with FSRT (FSRT group); 11 with surgery followed by conventional radiotherapy (S/CR group); and 14 with conventional radiotherapy (CR group). Survival and local control rates were determined for patients who had an ECOG performance status of 0-2. RESULTS Overall median survival rate was 18 months, and actuarial 1- and 2-year survival rates were 57.6% and 31.0%, respectively. Median survival rates were 25.6 months for the FSRT group, 18.7 months for the S/CR group, and 4.3 months for the CR group. Significant prognostic factors associated with survival were age less than 60 years and good performance status. In patients treated with FSRT, imaging studies revealed that 21 of 24 tumors (88%) were locally controlled during a median follow-up time of 5.2 months (range 0.5-68). Actuarial 1- and 2-year local control rates were 89.6% and 55.2%, respectively. No patient suffered from acute or late complications during and following FSRT. CONCLUSIONS FSRT offers better tumor control and prolonged survival over the S/CR or CR groups, and should be considered as primary treatment for brain metastases from RCC. Patients under 60-years-old and those with a good performance status at the beginning of radiotherapy had a better prognosis.
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Internalization of CD26 by mannose 6-phosphate/insulin-like growth factor II receptor contributes to T cell activation. Proc Natl Acad Sci U S A 2000; 97:8439-44. [PMID: 10900005 PMCID: PMC26966 DOI: 10.1073/pnas.97.15.8439] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
CD26 is a T cell activation antigen known to bind adenosine deaminase and have dipeptidyl peptidase IV activity. Cross-linking of CD26 and CD3 with immobilized mAbs can deliver a costimulatory signal that contributes to T cell activation. Our earlier studies revealed that cross-linking of CD26 induces its internalization, the phosphorylation of a number of proteins involved in the signaling pathway, and subsequent T cell proliferation. Although these findings suggest the importance of internalization in the function of CD26, CD26 has only 6 aa residues in its cytoplasmic region with no known motif for endocytosis. In the present study, we have identified the mannose 6-phosphate/insulin-like growth factor II receptor (M6P/IGFIIR) as a binding protein for CD26 and that mannose 6-phosphate (M6P) residues in the carbohydrate moiety of CD26 are critical for this binding. Activation of peripheral blood T cells results in the mannose 6 phosphorylation of CD26. In addition, the cross-linking of CD26 with an anti-CD26 antibody induces not only capping and internalization of CD26 but also colocalization of CD26 with M6P/IGFIIR. Finally, both internalization of CD26 and the T cell proliferative response induced by CD26-mediated costimulation were inhibited by the addition of M6P, but not by glucose 6-phosphate or mannose 1-phosphate. These results indicate that internalization of CD26 after cross-linking is mediated in part by M6P/IGFIIR and that the interaction between mannose 6-phosphorylated CD26 and M6P/IGFIIR may play an important role in CD26-mediated T cell costimulatory signaling.
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New operative method for distal aortic arch aneurysm: combined cervical branch bypass and endovascular stent-graft implantation. J Thorac Cardiovasc Surg 1999; 117:832-4. [PMID: 10096986 DOI: 10.1016/s0022-5223(99)70311-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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CD26/dipeptidyl peptidase IV differentially regulates the chemotaxis of T cells and monocytes toward RANTES: possible mechanism for the switch from innate to acquired immune response. Int Immunol 1999; 11:417-26. [PMID: 10221653 DOI: 10.1093/intimm/11.3.417] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
CD26, a 110 kDa cell surface glycoprotein, exhibits dipeptidyl peptidase IV (DPPIV; EC 3.4.14.5) enzyme activity and plays an important role in T cell co-stimulation. In the present study, the function of CD26/DPPIV in transendothelial migration was examined using beta-chemokines as chemoattractants. When soluble recombinant CD26 (sCD26/DPPIV+) was added to the transendothelial chemotaxis system, chemotactic migration of T cells toward RANTES was significantly enhanced. Addition of sCD26 to 50 ng/ml of RANTES enhanced the migratory response by a factor of two compared to RANTES alone, whereas mutant soluble CD26 (mCD26), lacking the DPPIV enzyme activity, had no enhancing effect on RANTES-induced T cell migration. In the process of analyzing the mechanisms of the enhancement of T cell migration by sCD26, we showed that RANTES was cleaved by sCD26 under physiologic conditions at the precise site characteristic of its enzyme specificity. However, synthesized RANTES which lacks two N-terminal amino acids showed a chemotactic activity equivalent to full-length RANTES on T cells. Furthermore, addition of sCD26 showed enhancement of T cell migration induced by both forms of RANTES. In contrast to T cells, the truncated RANTES is inactive in chemotaxis of purified monocytes and supplement of sCD26 but not mCD26 reduced the migratory response of monocytes to RANTES. These results suggest that CD26/DPPIV differentially regulate the chemotactic response of T cells and monocytes to RANTES.
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Abstract
BACKGROUND: Breast conserving therapy is being established as a standard therapeutic procedure for early breast cancer in Japan. However, the indications of radiotherapy and a standardized therapeutic procedure have not been established yet. In this study, complications following radiotherapy were evaluated in patients who had previously undergone breast conserving therapy at Tokushima University Hospital. METHODS From October 1989 to March 1996, 60 women with stage I or II breast cancer underwent radiation therapy after breast conserving surgery, and all patients were followed-up for a median of 27 months. Radiation morbidity scoring of the breast and adjacent organs was performed using the toxity criteria of the Radiation Therapy Oncology Group (RTOG) and European Organization for Research andTreatment of Cancer (EORTC). RESULTS: Only 1 patient developed local recurrence, and no distant metastasisor death was observed. The cause of recurrence in 1 case was considered to be due to extended intraductal component. Although transient dermal reaction was induced by irradiation of the breast, no side effects that may cause cosmetic problems were found. No serious radiation complications were found in the lungs, ribs, heart or other adjacent organs. CONCLUSION: The adverse reactions caused by irradiation does not reduce the merit of combined use of radiation therapy in breast conserving therapy, and therefore, are not the hesitation factor in application of radiotherapy.
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Detection of virulent Rhodococcus equi in tracheal aspirate samples by polymerase chain reaction for rapid diagnosis of R. equi pneumonia in foals. Vet Microbiol 1998; 61:59-69. [PMID: 9646466 DOI: 10.1016/s0378-1135(98)00163-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Polymerase chain reaction (PCR)-based assays were developed to detect virulent Rhodococcus equi in transtracheal aspirate samples from sick foals showing respiratory signs. An oligonucleotide primer pair from the sequence of the virulence-associated 15- to 17-kDa antigen gene of the virulence plasmid in virulent R. equi was used to amplify a 564 bp region by PCR, and the result was confirmed by Southern blot hybridization. No positive reaction was seen in DNA from 13 different microorganisms typically found in the respiratory tract. In tracheal aspirates seeded with virulent R. equi, a visible band could detect 10 to 10(2) bacteria per PCR assay (10(3) to 10(4)/ml of the aspirate). Virulent R. equi was demonstrated in 31 of 42 transtracheal aspirates by culture and colony blot analysis, whereas a positive PCR result was observed in only 12 of the 31 culture positive samples. To prevent false-negative results, two methods were developed: a nested PCR and a PCR in combination with enrichment cultures of aspirates in the selective medium to increase the number of bacteria to 10(4)/ml or more. All of the PCR-negative and culture-positive samples were positive by the two methods. These results indicated that PCR-based assays provide a specific and sensitive means to detect virulent R. equi in tracheal aspirates of foals, and they are more rapid than the routine culture procedures for the diagnosis of R. equi pneumonia in foals.
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Abstract
Pentoxifylline (PTX), a methylxanthine derivative, was examined for its effects on T cell proliferation and cytokine production stimulated by cross-linking anti-CD3 alone, anti-CD3 with PMA, anti-CD3 with anti-CD26, or anti-CD3 with anti-CD28 mAb, respectively. PTX at a 3.5 x 10(-5) M concentration significantly inhibited T cell proliferation and the production of tumor necrosis factor-alpha, interleukin-2, and interleukin-4. Moreover, this effect was selective for stimulation by cross-linking anti-CD3 with PMA, or anti-CD3 with anti-CD26, but not by cross-linking anti-CD3 with anti-CD28. These results suggest that the inhibitory effect of PTX on T cell activation involves the CD3 and CD26, but not the CD28 signal pathway.
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[Eight cases of intracranial arteriovenous malformations treated by conventional radiation therapy]. RINSHO HOSHASEN. CLINICAL RADIOGRAPHY 1990; 35:315-9. [PMID: 2111859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We conducted radiotherapy in 8 cases of intracranial arteriovenous malformation that had difficult embolectomy and other surgery from 1983 to October, 1988. The results in 6 cases of dural arteriovenous malformation at the cavernous sinus were "marked effect" in 4 cases, "relapse" in 1 case, and "no effect" in 1 case. One case of dural arteriovenous malformation at the sigmoid venous sinus demonstrated only slight irradiation effect. No irradiation effect was observed in 1 case of cerebral arteriovenous malformation.
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Abstract
A new species of Streptomyces is described and designated Streptomyces auranticolor (FERM-P No. 5365) which produces new anticoccidial antibiotics, designated as WS-5995 A and WS-5995 B. The organism is characterized by gray spore mass color, spiral spore chain with smooth spores, non-chromogenic reaction, soluble pigment, and carbon utilization characteristics. It differs from previously described streptomycetes on the basis of carbon utilization, and pigment production.
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Abstract
WS-5995 A, B and C are produced by a new strain of Streptomyces designated Streptomyces auranticolor. These antibiotics were purified by solvent extraction followed by chromatography on silica gel and then crystallized. WS-5995 A (C19H12O6, m.p., 289 approximately 291 degrees C) and WS-5995 B (C19H14O6, sublimation at 300 degrees C) protect chickens from infection with Eimeria tenella, a species of coccidia, which produces morbidity or mortality in chickens. WS-5995 C (C19H14O 7, m.p. 288 approximately 290 degrees C), a biologically inactive component, was found to be converted to WS-5995 A on treatment with trifluoroacetic anhydride.
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[Indication of open treatment for tuberculous empyema thoracis (author's transl)]. KEKKAKU : [TUBERCULOSIS] 1979; 54:85-8. [PMID: 439570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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[Bronchial calculi with a rare clinical course]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 1975; 28:347-50. [PMID: 1170438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Thiopeptin, a new feed additive antibiotic: microbiological and chemical studies. Antimicrob Agents Chemother 1972; 1:192-6. [PMID: 5045467 PMCID: PMC444191 DOI: 10.1128/aac.1.3.192] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The thiopeptins are a new group of sulfur-containing peptide antibiotics produced by Streptomyces tateyamensis. The antibiotic consists of a major component (designated as thiopeptin B) and four minor ones (thiopeptins A(1) to A(4)). These components were isolated by solvent extraction from mycelium followed by chromatography on silica gel with various ratios of chloroform and methanol as elution solvents. Acid hydrolysis of each of the thiopeptin components yielded 1 mole of valine, 1 of threonine, 1 of cysteine, and 2 of alanine as amino acids. Each component of the thiopeptin A group has chemical and biological properties closely similar to those of thiopeptin B, but detailed characterization has established that thiopeptins A(1), A(3), and A(4) are new antibiotics. We could not obtain accurate data for determination of the uniqueness of A(2) because of insufficient sample. Thiopeptin has strong antibacterial activity against gram-positive bacteria and Mycoplasma, and exhibits no cross-resistance to major human-use antibiotics.
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