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Eunhee S. Yi Adriana Bedoya Hyesun Lee Elaine Chin William Saunders Seong -Jin Kim David Danielpour Daniel G. Remick Songmei Yin Thomas R. Ulich 《Inflammation》1996,20(4):339-352
Cytokine release from irradiated cells has been postulated to start soon after irradiation preceding detectable clinical and pathological manifestation of lung injury. The expression of transforming growth factor beta (TGF), a fibrogenic and radiation-inducible cytokine, was studied from 1–16 weeks after the 15 and 30 Gray (Gy) of thoracic irradiation to rats. Thoracic irradiation caused an increase in TGF protein in bronchoalveolar lavage (BAL) fluid peaking at 3–6 weeks as compared to sham-irradiated control rats. Steady state TGF mRNA expression as shown by whole lung northern blot assay paralleled the TGF protein expression in BAL fluid. The peak of TGF protein increase in BAL fluid between 3 and 6 weeks coincided with the initial influx of inflammatory cells in BAL fluid, but preceded histologically discernable pulmonary fibrosis that was not apparent until 8–10 weeks after irradiation. In conclusion, TGF and mRNA and protein upregulation preceded the radiation-induced pulmonary fibrosis, suggesting a pathogenetic role in the development of radiation fibrosis. 相似文献
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Dahae Won Chan‐Jeoung Park Hyoeun Shim Seongsoo Jang Hyun‐Sook Chi Jooryung Huh Dok Hyun Yoon Cheolwon Suh 《Histopathology》2013,62(3):397-405
Aims: Bone marrow (BM) biopsies of some mucosa‐associated lymphoid tissue (MALT) lymphoma patients show scattered or small clusters of CD20+ cells without definite lesions (subtle CD20 positivity). The aim of this study was to evaluate the clinical significance of BM involvement and subtle CD20 positivity in 122 patients diagnosed with MALT lymphoma. Methods and results: Patients were divided into three categories: BM involvement [BM(+)], subtle CD20 positivity, and no BM involvement [BM(?)]. Eleven (9%) showed BM involvement, and 17 (14%) showed subtle CD20 positivity. BM(+) patients had significantly worse progression‐free survival (PFS) than BM(?) patients [hazard ratio (HR) 6.25, P = 0.01], but there was no significant difference between subtle CD20 positivity and BM(?) patients. Patients with >30 CD3+ cells among 100 nucleated cells in the areas with increased numbers of CD3+ cells had significantly worse PFS than those with <15 CD3+ cells (HR 5.49, P = 0.02). BM(+) patients with >30 CD3+ cells had worse PFS than those with ≤30 CD3+ cells (P = 0.029), with an extent of BM(+) involvement of >10% positively correlating with >30 CD3+ cells (P = 0.015). Conclusions: Patients with BM(+) MALT lymphoma showed significantly worse PFS than those with subtle CD20 positivity and BM(?) MALT lymphoma, but the PFS of patients with subtle CD20 positivity MALT lymphoma was not significantly different from that of those with BM(?) MALT lymphoma. Increased numbers of BM T cells in MALT lymphoma patients might be suggestive of a worse prognosis. 相似文献
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Polychlorinated dibenzo‐p‐dioxins and dibenzofurans levels in piglet liver with various diseases 下载免费PDF全文
Jeoung Hwa Shin Won Hyun Ji Chanhee Chae Shela Gorinstein Yun Gyong Ahn 《International journal of experimental pathology》2017,98(4):214-220
This study deals with the levels of toxic polychlorinated dibenzo‐p‐dioxin and furan congeners (PCDD/Fs) in the livers of piglets affected by infectious diseases using isotope dilution high‐resolution gas chromatography/high‐resolution mass spectrometry (HRGC/HRMS). Seventeen toxic congeners in the liver samples infected with bacterial and viral diseases were compared. For porcine reproductive and respiratory syndrome virus (PRRSV) samples, the North American‐ and European‐type PRRS diseases were observed. This study shows that there are significantly different levels of PCDD/Fs, present, which vary according to the types of diseases as evidenced by our analysis of the piglet liver samples. 相似文献
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Trinh T. Nguyen Hiroshi Sekiguchi Eunhee S. Yi Jay H. Ryu 《The American journal of medicine》2021,134(7):926-929
BackgroundIntrathoracic involvement with lymphomas is common and manifests lymphadenopathy as well as a wide spectrum of imaging abnormalities in the lungs. Intravascular large B-cell lymphoma (IVLBCL) is a rare extranodal subtype of large B-cell lymphoma that typically involves small blood vessels and is difficult to detect.MethodsUsing a computer-assisted search, we identified patients with histopathologically proven IVLBCL in the lungs at Mayo Clinic from 2001 through 2018. Medical records, imaging studies, and pathologic specimens were reviewed.ResultsA total of 5 patients were diagnosed with a median age at diagnosis of 68 years (range, 44-73); 4 patients were male. The diagnosis of IVLBCL was achieved by surgical lung biopsy in 3 and at autopsy in 2. At presentation, all 5 patients had dyspnea and systemic symptoms including fever, fatigue, night sweats, and/or weight loss. Chest radiography and computed tomography (CT) failed to demonstrate the diffuse infiltrative process; positron emission tomography (PET) scan performed in 2 patients did not show fluorodeoxyglucose (FDG) uptake in the lungs. Pulmonary function tests obtained in 3 patients showed reduced diffusing capacity in all; transthoracic echocardiography yielded evidence of pulmonary hypertension in 2 of 4 patients. All 3 patients diagnosed antemortem underwent chemotherapy with 1 patient remaining alive at 4 years after diagnosis.ConclusionsIVLBCL is difficult to diagnose given variable and nonspecific clinical presentations. Microvascular disease processes such as IVLBCL should be kept in mind in cases of undiagnosed progressive dyspnea accompanied by systemic symptoms even when imaging studies are unrevealing. 相似文献
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Growth hormone releasing hormone (GHRH) signals via G protein-coupled receptors (GHRH-R) to enhance intracellular Gαs/adenylyl
cyclase/cAMP signaling, which in turn has positive effects on GH synthesis and release, as well as proliferation of the GH-producing
cells of the anterior pituitary gland. Some GH-producing pituitary tumors express a constitutively active mutant form of Gαs
(gsp oncogene). It has been reported that these tumors are more responsive to octreotide therapy. In this study we used a rat
GH-producing cell line (GH3) stably transfected with the human GHRH-R cDNA (GH3-GHRHR cells) as a model to study the effects
of gsp oncogene on somatostatin (SRIH) receptor subtype 1 and 2 (sst1 and sst2) mRNA levels. Transient transfection of gsp oncogene in GH3-GHRHR cells for 48 h increased intracellular cAMP levels and GH release. Phosphodiesterase (PDE) 4, sst1
and sst2 mRNA levels were increased by G protein mutation as assessed by real-time RT-PCR. Increased PDE mRNA levels in gsp-transfected cells may be a compensatory mechanism to the constitutive activation of cAMP-dependent pathway by G protein mutation
and is consistent with reports of higher PDE expression in human pituitary tumor that express gsp. Our data suggest that higher expression of sst1 and sst2 mRNA induced by the gsp oncogene may be a mechanism by which gsp-positive tumors show a greater response to SRIH. GH3 cells permanently transfected with GHRH-R can be used for in vitro studies of actions of GHRH. 相似文献
9.
Purpose
To investigate peripheral lamina cribrosa depth (PLCD) and its vertical-horizontal difference in eyes with primary open-angle glaucoma (POAG).Methods
Patients with POAG (n=90 eyes) and age-matched healthy individuals (n=90 eyes) underwent swept-source optical coherence tomography (SS-OCT) scans centered at the optic discs. The PLCD was defined as the vertical distance between the most peripheral visible end of anterior lamina cribrosa (LC) surface and the reference plane connecting the Bruch''s membrane openings. The PLCD in each quadrant region and the vertical-horizontal PLCD difference were compared between the POAG and healthy eyes. The clinical factors associated with increased PLCD were evaluated.Results
The PLCD was significantly larger in the POAG eyes than the control eyes at the horizontal (P=0.034) and vertical (P=0.001) meridians. The vertical PLCD was significantly larger than the horizontal PLCD, both in the POAG eyes (P<0.001) and in the control eyes (P=0.003). However, the vertical-horizontal PLCD difference was significantly larger in the POAG eyes (47±60 μm) than in the control eyes (18±54 μm, P=0.001). Multivariate regression showed a significant association of male gender (P=0.005), increased baseline IOP (P=0.043), and decreased MD of VF (P=0.025) with increased PLCD.Conclusions
The peripheral LC was displaced more posteriorly in the POAG eyes compared with the age-matched healthy eyes. In the POAG eyes, the peripheral LC was displaced more posteriorly at the vertical meridian than at the horizontal meridian. The peripheral LC in the vertical meridian might have increased IOP-related strain (deformation) compared with horizontal meridian in glaucomatous eyes. 相似文献10.