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1.
Nutrients ; 15(18)2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37764856

ABSTRACT

A high-fat diet (HFD) is a major risk factor for cardiovascular diseases. Many pure compounds have been demonstrated to be effective in treating cardiovascular diseases. In this study, we investigated the alleviating effects of oral ovatodiolide and antcin K (OAK) supplements on HFD-induced cardiovascular dysfunction in apolipoprotein E (ApoE)-knockout mice. Cardiovascular dysfunction was induced in ApoE-knockout mice by feeding them an HFD for 12 weeks. The degree of cardiovascular dysfunction was assessed through echocardiography, hematological and biochemical analyses, and immunofluorescence and immunohistochemical staining. The HFD-fed mice exhibited cardiovascular dysfunction-abnormal blood biochemical index. The arterial wall tissue exhibited the marked deposition of lipids, upregulated expression of vascular cell adhesion molecule-1 and CD36 receptors, and downregulated expression of the ABCA1 receptor. Macrophages isolated from the peritoneal cavity of the mice exhibited increased levels of lipid accumulation, reactive oxygen species, and CD11b expression but reduced mitochondrial membrane potential. The expression of superoxide dismutase 2 was downregulated and that of tumor necrosis factor-α was upregulated in the myocardial tissue. Oral OAK supplements twice a day for 12 weeks significantly mitigated HFD-induced cardiovascular dysfunction in the experimental mice. Oral OAK supplements appear to be a promising strategy for treating HFD-induced cardiovascular dysfunction. The underlying mechanisms may involve the reduction of lipid accumulation in the artery and oxidative stress and inflammation in the cardiovascular tissue.


Subject(s)
Cardiovascular Diseases , Diet, High-Fat , Animals , Mice , Diet, High-Fat/adverse effects , Oxidative Stress , Apolipoproteins E/genetics
2.
Front Pharmacol ; 12: 720018, 2021.
Article in English | MEDLINE | ID: mdl-34512347

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes severe "flu-like" symptoms that can progress to acute respiratory distress syndrome (ARDS), pneumonia, renal failure, and death. From the therapeutic perspective, 3-chymotrypsin-like protein (3CLpro) is a plausible target for direct-acting antiviral agents because of its indispensable role in viral replication. The flavonoid ugonin J (UJ) has been reported to have antioxidative and anti-inflammatory activities. However, the potential of UJ as an antiviral agent remains unexplored. In this study, we investigated the therapeutic activity of UJ against SARS-CoV-2 infection. Importantly, UJ has a distinct inhibitory activity against SARS-CoV-2 3CLpro, compared to luteolin, kaempferol, and isokaempferide. Specifically, UJ blocks the active site of SARS-CoV-2 3CLpro by forming hydrogen bonding and van der Waals interactions with H163, M165 and E166, G143 and C145, Q189, and P168 in subsites S1, S1', S2, and S4, respectively. In addition, UJ forms strong, stable interactions with core pharmacophore anchors of SARS-CoV-2 3CLpro in a computational model. UJ shows consistent anti-inflammatory activity in inflamed human alveolar basal epithelial A549 cells. Furthermore, UJ has a 50% cytotoxic concentration (CC50) and a 50% effective concentration (EC50) values of about 783 and 2.38 µM, respectively, with a selectivity index (SI) value of 329, in SARS-CoV-2-infected Vero E6 cells. Taken together, UJ is a direct-acting antiviral that obstructs the activity of a fundamental protease of SARS-CoV-2, offering the therapeutic potential for SARS-CoV-2 infection.

3.
Br J Radiol ; 88(1048): 20140730, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25608494

ABSTRACT

OBJECTIVE: To systematically investigate the effect of CT localizer radiograph acquisition on the tube current modulation and thus radiation dose of the subsequent diagnostic scan. METHODS: Localizer radiographs of an abdominal section CT phantom were taken, and the resulting volume CT dose index (CTDIvol) for the diagnostic scan was recorded. Variables included tube potential, the phantom's alignment within the CT scanner gantry in both the vertical and horizontal directions and the X-ray source angle at which the localizer was acquired. RESULTS: Diagnostic scan CTDIvol decreased with increasing tube potential. Vertical (table height) movement was found to affect radiation dose more than horizontal movement, with ±50 mm table movement resulting in a standard deviation in the diagnostic scan CTDIvol of 4.4 mGy, compared with 2.5 mGy with ±50 mm horizontal movement. Correspondingly, localizer angles of 90° or 270° (3 o'clock and 9 o'clock X-ray source positions) were less sensitive overall to alignment errors, with a standard deviation of 2.5 mGy, compared with a 0° or 180° angle, which had a standard deviation of 3.8 mGy. CONCLUSION: To achieve a consistently optimized radiation dose, the localizer protocol should be paired with the diagnostic acquisition protocol. A final acquisition angle of 90° should be used when possible to minimize dose variation resulting from alignment errors. ADVANCES IN KNOWLEDGE: Localizer parameters that affect radiation output were identified for this scanner system. The importance of tube potential and acquisition angle was highlighted.


Subject(s)
Radiation Dosage , Tomography, X-Ray Computed/standards , Contrast Media , Humans , Iohexol , Phantoms, Imaging , Radiography, Abdominal , Tomography Scanners, X-Ray Computed
4.
Br J Cancer ; 109(7): 1725-34, 2013 Oct 01.
Article in English | MEDLINE | ID: mdl-24022191

ABSTRACT

BACKGROUND: This phase 1 clinical trial was conducted to determine the safety, maximum-tolerated dose (MTD), and pharmacokinetics of imatinib, bevacizumab, and metronomic cyclophosphamide in patients with advanced colorectal cancer (CRC). METHODS: Patients with refractory stage IV CRC were treated with bevacizumab 5 mg kg(-1) i.v. every 2 weeks (fixed dose) plus oral cyclophosphamide q.d. and imatinib q.d. or b.i.d. in 28-day cycles with 3+3 dose escalation. Response was assessed every two cycles. Pharmacokinetics of imatinib and cyclophosphamide and circulating tumour, endothelial, and immune cell subsets were measured. RESULTS: Thirty-five patients were enrolled. Maximum-tolerated doses were cyclophosphamide 50 mg q.d., imatinib 400 mg q.d., and bevacizumab 5 mg kg(-1) i.v. every 2 weeks. Dose-limiting toxicities (DLTs) included nausea/vomiting, neutropaenia, hyponatraemia, fistula, and haematuria. The DLT window required expansion to 42 days (1.5 cycles) to capture delayed toxicities. Imatinib exposure increased insignificantly after adding cyclophosphamide. Seven patients (20%) experienced stable disease for >6 months. Circulating tumour, endothelial, or immune cells were not associated with progression-free survival. CONCLUSION: The combination of metronomic cyclophosphamide, imatinib, and bevacizumab is safe and tolerable without significant drug interactions. A subset of patients experienced prolonged stable disease independent of dose level.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Agents/therapeutic use , Benzamides/therapeutic use , Colorectal Neoplasms/drug therapy , Cyclophosphamide/therapeutic use , Piperazines/therapeutic use , Pyrimidines/therapeutic use , Adult , Aged , Angiogenesis Inhibitors/adverse effects , Angiogenesis Inhibitors/pharmacokinetics , Angiogenesis Inhibitors/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/pharmacokinetics , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Benzamides/adverse effects , Benzamides/pharmacokinetics , Bevacizumab , Cyclophosphamide/adverse effects , Cyclophosphamide/pharmacokinetics , Drug Administration Schedule , Female , Humans , Imatinib Mesylate , Male , Maximum Tolerated Dose , Middle Aged , Neoplastic Cells, Circulating/drug effects , Piperazines/adverse effects , Piperazines/pharmacokinetics , Pyrimidines/adverse effects , Pyrimidines/pharmacokinetics , Treatment Outcome
5.
Ann Oncol ; 24(7): 1900-1907, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23519998

ABSTRACT

BACKGROUND: Based upon preclinical evidence for improved antitumor activity in combination, this phase I study investigated the maximum-tolerated dose (MTD), safety, activity, pharmacokinetics (PK), and biomarkers of the mammalian target of rapamycin inhibitor, temsirolimus, combined with sorafenib in hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Patients with incurable HCC and Child Pugh score ≤B7 were treated with sorafenib plus temsirolimus by 3 + 3 design. The dose-limiting toxicity (DLT) interval was 28 days. The response was assessed every two cycles. PK of temsirolimus was measured in a cohort at MTD. RESULTS: Twenty-five patients were enrolled. The MTD was temsirolimus 10 mg weekly plus sorafenib 200 mg twice daily. Among 18 patients at MTD, DLT included grade 3 hand-foot skin reaction (HFSR) and grade 3 thrombocytopenia. Grade 3 or 4 related adverse events at MTD included hypophosphatemia (33%), infection (22%), thrombocytopenia (17%), HFSR (11%), and fatigue (11%). With sorafenib, temsirolimus clearance was more rapid (P < 0.05). Two patients (8%) had a confirmed partial response (PR); 15 (60%) had stable disease (SD). Alpha-fetoprotein (AFP) declined ≥50% in 60% assessable patients. CONCLUSION: The MTD of sorafenib plus temsirolimus in HCC was lower than in other tumor types. HCC-specific phase I studies are necessary. The observed efficacy warrants further study.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , alpha-Fetoproteins/metabolism , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Biomarkers/blood , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/pathology , Disease-Free Survival , Drug Administration Schedule , Female , Humans , Liver Neoplasms/blood , Liver Neoplasms/pathology , Male , Maximum Tolerated Dose , Middle Aged , Neoplastic Cells, Circulating , Niacinamide/administration & dosage , Niacinamide/analogs & derivatives , Phenylurea Compounds/administration & dosage , Protein Precursors/blood , Prothrombin , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , Sorafenib , Treatment Outcome
6.
Br J Radiol ; 85(1013): 613-22, 2012 May.
Article in English | MEDLINE | ID: mdl-21791503

ABSTRACT

OBJECTIVE: The purpose of this study was to describe quantitative dual energy CT (DECT) findings and their accuracy in the detection of acute and subacute pulmonary embolism (PE) in rabbits. METHODS: Pulmonary emboli were created in 24 rabbits by gelatin sponge femoral vein injection. Conventional CT pulmonary angiography (CTPA) and DECT were obtained at either 2 h, 1 day, 3 days or 7 days after embolisation (n=6 rabbits for each time point). The location and number of PEs in the different stages were recorded at CTPA and iodine maps from DECT on a per-lobe basis. With histopathology as the reference standard, sensitivity and specificity of CTPA and DECT were calculated. CT and iodine map overlay values of the embolic and non-embolic areas were measured for each scan. RESULTS: With histopathology as the reference standard, the overall sensitivity and specificity of CTPA were 98% and 100% and those of iodine maps were 100% and 95%, respectively. Conventional CT and iodine map values of the embolised and non-embolised areas were significantly different between 2 h and 1 day (p<0.001), but not between 3 days and 7 days (p>0.05). A statistical difference was found for overlay values measured in the embolic and non-embolic regions for four groups. CONCLUSION: Iodine maps derived from DECT show alterations in lung perfusion for acute and subacute PE in an experimental rabbit model and show comparable sensitivity for PE detection and conventional CTPA.


Subject(s)
Pulmonary Artery/diagnostic imaging , Pulmonary Embolism/diagnostic imaging , Tomography, X-Ray Computed/methods , Animals , Contrast Media , Disease Models, Animal , Gelatin Sponge, Absorbable , Iodine Radioisotopes , Pulmonary Embolism/chemically induced , Rabbits , Sensitivity and Specificity
7.
Clin Radiol ; 65(12): 1031-7, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21070909

ABSTRACT

Common benign gynaecological diseases, such as leiomyoma, adenomyosis, endometriosis, and mature teratoma, rarely undergo malignant transformation. Benign transformations that may mimic malignancy include benign metastasizing leiomyoma, massive ovarian oedema, decidualization of endometrioma, and rupture of mature teratoma. The aim of this review is to provide a contemporary overview of imaging findings in malignant and apparent malignant transformation of benign gynaecological disease.


Subject(s)
Adenomyoma/diagnosis , Cell Transformation, Neoplastic , Endometriosis/diagnosis , Ovarian Neoplasms/diagnosis , Teratoma/diagnosis , Adult , Edema/diagnosis , Female , Humans , Magnetic Resonance Imaging , Middle Aged , Ovarian Diseases/diagnosis , Tomography, X-Ray Computed
8.
Br J Radiol ; 83(992): 707-18, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20551257

ABSTRACT

The introduction of modern dual-energy CT (DECT) scanners has enabled contrast material to be distinguished at imaging without the need for a separate unenhanced scan. Images of pulmonary parenchymal contrast enhancement obtained using DECT improve the detection of defects, augmenting our ability to detect pulmonary emboli; however, with these advances new pitfalls are also introduced. In this pictorial review, we present the technique, clinical applications and causes and remedies of false results of dual-energy pulmonary parenchymal enhancement defects in pulmonary embolism.


Subject(s)
Pulmonary Artery/diagnostic imaging , Pulmonary Embolism/diagnostic imaging , Radiography, Dual-Energy Scanned Projection/methods , Tomography, X-Ray Computed/methods , Adult , Female , Humans , Male , Middle Aged , Prognosis , Radiographic Image Interpretation, Computer-Assisted , Radiography, Dual-Energy Scanned Projection/instrumentation , Sensitivity and Specificity , Tomography, X-Ray Computed/instrumentation
9.
Singapore Med J ; 51(2): e30-3, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20358139

ABSTRACT

Deafness is a common and often permanent neurological sequel of Streptococcus (S.) suis meningitis. Suppurative labyrinthitis, rather than direct auditory nerve infection, has been found to be the site responsible for deafness. Neuroimaging is important to localise the site involved in hearing loss and to assess the feasibility of a cochlear implantation. S. suis is very sensitive to penicillin. Although a relapse of S. suis meningitis is uncommon, it can occur despite an adequate duration of appropriate antibiotic therapy. We describe a patient with S. suis meningitis, who developed permanent deafness from haemorrhagic labyrinthitis, as shown on magnetic resonance imaging. She suffered a relapse despite a seven-week course of intravenous antibiotics. A review on six cases of relapse reported in the literature shows that relapses occurred despite two to four weeks of antibiotics being administered to the patients. The clinical implications and treatment of relapse are discussed.


Subject(s)
Hearing Loss/etiology , Hemorrhage/complications , Labyrinthitis/complications , Meningitis, Bacterial/complications , Streptococcal Infections/complications , Streptococcus suis , Aged , Anti-Bacterial Agents/therapeutic use , Ceftriaxone/therapeutic use , Cochlea/physiopathology , Cochlear Implants , Female , Hearing Loss/physiopathology , Hearing Loss/therapy , Humans , Magnetic Resonance Imaging , Recurrence , Streptococcal Infections/drug therapy
11.
HPB (Oxford) ; 10(1): 63-9, 2008.
Article in English | MEDLINE | ID: mdl-18695762

ABSTRACT

BACKGROUND: Cystic pancreatic neoplasms (CPNs) present a unique challenge in preoperative diagnosis. We investigated the accuracy of diagnostic methods for CPN. MATERIAL AND METHODS: This retrospective cases series includes 70 patients who underwent surgery at a university hospital for presumed CPNs between 1997 and 2003, and for whom a definitive diagnosis was established. Variables examined included symptoms, preoperative work-up (including endoscopic retrograde cholangiopancreatography (ERCP) in 22 cases and endoscopic ultrasound (EUS) in 12), and operative and pathological findings. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) scans (n=50 patients; CT=48; MRI=13) were independently reviewed by two blinded GI radiologists. RESULTS: The final histopathologic diagnoses were mucinous cystic neoplasm (n=13), mucinous cystadenocarcinoma (10), serous cystadenoma (11), IPMN (14), simple cyst (3), cystic neuroendocrine tumor (5), pseudocyst (4), and other (10). Overall, 25 of 70 were malignant (37%), 21 premalignant (30%), and 24 benign (34%). The attending surgeon's preoperative diagnosis was correct in 31% of cases, incorrect in 29%, non-specific "cystic tumor" in 27%, and "pseudocyst vs. neoplasm" in 11%. Eight had been previously managed as pseudocysts, and 3 pseudocysts were excised as presumed CPN. In review of the CT and MRI, a multivariate analysis of the morphologic features did not identify predictors of specific pathologic diagnoses. Both radiologists were accurate with their preferred (no. 1) diagnosis in <50% of cases. MRI demonstrated no additional utility beyond CT. CONCLUSIONS: The diagnosis of CPN remains challenging. Cross-sectional imaging methods do not reliably give an accurate preoperative diagnosis. Surgeons should continue to err on the side of resection.

12.
Abdom Imaging ; 30(1): 105-7, 2005.
Article in English | MEDLINE | ID: mdl-15647879

ABSTRACT

We report a patient with acute pyelonephritis in whom the dominant computed tomographic findings were ascending colon and cecal wall thickening and pericolonic fat stranding, likely related to contiguous inflammation from the right kidney. To our knowledge, this is the first report of acute pyelonephritis affecting the right colon mimicking colitis on computed tomography.


Subject(s)
Colitis/diagnostic imaging , Pyelonephritis/diagnostic imaging , Tomography, X-Ray Computed , Adult , Female , Humans , Kidney/diagnostic imaging , Ureter/diagnostic imaging
13.
Abdom Imaging ; 29(4): 505-6, 2004.
Article in English | MEDLINE | ID: mdl-15024511

ABSTRACT

Peritoneal involvement is a rare extrapulmonary manifestation of coccidioidomycosis. We report a patient with meningeal coccidioidomycosis who was found to have multiple, globular, peripherally enhancing deposits in the peritoneal cavity at abdominal computed tomography, raising the consideration of peritoneal malignancy. Aspiration biopsy demonstrated peritoneal coccidioidomycosis. The particular computed tomographic findings of peritoneal coccidioidomycosis seen in this patient have not been previously described.


Subject(s)
Coccidioidomycosis/diagnosis , Peritoneal Cavity/diagnostic imaging , Peritoneal Diseases/diagnosis , Peritoneal Neoplasms/diagnosis , Tomography, X-Ray Computed/methods , Adult , Diagnosis, Differential , Humans , Male , Meningitis, Fungal/complications , Meningitis, Fungal/diagnosis , Peritoneal Cavity/microbiology , Peritoneal Diseases/microbiology , Radiography, Abdominal/methods
14.
Am J Surg Pathol ; 25(9): 1158-66, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11688575

ABSTRACT

Laparoscopic nephrectomy is a novel approach for small renal tumors in selected patients; however, removal of the kidney through the small laparoscopic abdominal wall incision site requires the kidney to be morcellated into small fragments while still in situ. Morcellation presents two problems for the pathologist. First, guidelines for optimal sampling of morcellated fragments have not been described. Second, morcellation precludes complete pTNM tumor staging, in particular, tumor size, margins, and renal vein involvement. Based on our initial experience with 23 laparoscopic nephrectomies/nephroureterectomies (13 clinically suspected neoplasms, confirmed pathologically as renal cell carcinoma [RCC, n = 7], urothelial carcinoma of the renal pelvis [n = 3], angiomyolipoma [n = 1], and cystic nephroma [n = 1], and 10 clinically benign entities) and a conservative statistical model, we present a decision analysis model of various specimen sampling protocols that optimize cost, labor, or time to diagnosis (single vs sequential sampling). Using the tumor-to-kidney volume ratio (TKR), calculated from preoperative radiologic imaging and specimen gross weight, several specimen sampling algorithms were compared. For the average situation in which TKR is > or =0.15, the algorithm that most significantly optimizes cost and labor is one that initially samples 5% of the morcellated specimen. However, additional sampling may be required in one fourth of the cases. The optimal amount of sampled tissue may indeed be less than 5% because this assumes no suspicious tissue is grossly visible and in all our cases of RCC grossly visible tumor was identified. Additional nomograms for a spectrum of TKR, sampling success, and cost are presented to allow pathologists their own discretion in determining optimal sampling of the morcellated kidney. Tumor staging is severely limited by morcellation. Tumor size, renal capsule involvement, and renal vein involvement cannot be fully pathologically evaluated for RCC, whereas invasion cannot be definitively assessed for urothelial carcinoma of the renal pelvis. Knowledge of the radiologic features (lesion size, capsule, and vein involvement) is important in sampling and staging morcellated kidneys removed laparoscopically.


Subject(s)
Carcinoma, Renal Cell/surgery , Kidney Neoplasms/surgery , Neoplasm Staging/methods , Nephrectomy/methods , Specimen Handling/methods , Algorithms , Carcinoma, Renal Cell/diagnostic imaging , Carcinoma, Renal Cell/pathology , Decision Support Techniques , Humans , Kidney Neoplasms/diagnostic imaging , Kidney Neoplasms/pathology , Kidney Pelvis/diagnostic imaging , Kidney Pelvis/pathology , Laparoscopy , Radiography , Urothelium/pathology
15.
Exp Mol Med ; 33(1): 29-31, 2001 Mar 31.
Article in English | MEDLINE | ID: mdl-11322483

ABSTRACT

Mutations of the transmembrane conductance regulator (CFTR) gene in cystic fibrosis lead to dysfunction of the lung, pancreas, and sweat glands, etc. To investigate the possibility of the relationship between lung cancer and the mutations of CFTR gene, we determined amino acid sequences using reverse transcription-polymerase chain reaction (RT-PCR) and DNA sequencing. In this study, the deletion mutation of 508th amino acid in one of nine lung caner patients was found confirming that CFTR gene mutation exists in a Korean lung cancer patient.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Lung Neoplasms/genetics , Sequence Deletion , Adult , Aged , Female , Humans , Korea , Male , Middle Aged
16.
Cancer Res Treat ; 33(6): 495-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-26680829

ABSTRACT

PURPOSE: The incidence of salivary gland tumor is approximately 2% among all head and neck tumors, of which malignant cases account for only about 5%. Much research has been performed in order to clarify the mechanism of oncogene activation, however salivary gland tumors remain understudied. We performed this study in order to characterize the ras gene in these tumors. MATERIALS AND METHODS: We treated white rats with 7, 12-dimethylbenz[a]anthracene (DMBA) and confirmed the occurrence of salivary gland tumors after ten to thirty weeks. Isolated genomic DNAs from tumor tissues were added to NIH 3T3 cells. In order to detect Ha-ras mutations, we performed a two-step PCR-RFLP and 7analyzed the mutated sequences. RESULTS: We induced salivary gland tumors by DMBA treatment in white rats. Isolated DNAs from the tumor tissues transformed the NIH 3T3 cells. Point mutations were observed in codons 12 and 61 of the Ha-ras oncogene. The total frequency of point mutations was 13.9% in DMBA-induced salivary gland tumors in rats. CONCLUSION: Our results demonstrate that a variety of cancers ras oncogene mutations were also found in salivary gland tumors. We confirmed that a point mutation of the Ha-ras oncogene in a DMBA-induced salivary gland tumor occurs at a frequency of 13.9%.

17.
J Immunol ; 165(7): 3951-8, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11034403

ABSTRACT

Unlike more well-studied large heat shock proteins (hsp) that induce both T cell antiinflammatory (IL-10, IL-4) and macrophage proinflammatory (TNF-alpha, IL-15, IL-12) cytokines, hsp27, a small hsp, has been primarily identified as a substrate of mitogen-activated protein kinase-activated protein kinase-2 involved in the p38 signaling pathway and activated during monocyte IL-10 production. Hsp27 can also act as an endogenous protein circulating in the serum of breast cancer patients and a protein whose induction correlates to protection from LPS shock. However, the cytokine-stimulating properties of hsp27 have been unexplored. In this study, exogenous hsp27 is demonstrated for the first time as a potent activator of human monocyte IL-10 production, but only a modest inducer of TNF-alpha. Although exogenous hsp27 stimulation activated all three monocyte mitogen-activated protein kinase pathways (extracellular signal-related kinase (ERK) 1/2, c-Jun N-terminal kinase, and p38), only p38 activation was sustained and required for hsp27 induction of monocyte IL-10, while both ERK 1/2 and p38 activation were required for induction of TNF-alpha when using the p38 inhibitor SB203580 or the ERK inhibitor PD98059. Hsp27's transient activation of the c-Jun N-terminal kinase pathway, which can down-regulate IL-10, may contribute to its potent IL-10 induction. Hsp27's ERK 1/2 activation was also less sustained than activation by stimuli like LPS, possibly contributing to its modest TNF-alpha induction. The failure of either PD98059 or anti-TNF-alpha Ab to substantially inhibit IL-10 induction implied that hsp27 induces IL-10 via activation of p38 signaling independently of TNF-alpha activation and may be predominantly an antiinflammatory monokine stimulus.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/immunology , Heat-Shock Proteins , Interleukin-10/biosynthesis , Monocytes/immunology , Monocytes/metabolism , Neoplasm Proteins/immunology , Tumor Necrosis Factor-alpha/biosynthesis , Adjuvants, Immunologic/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Cell Separation , Dose-Response Relationship, Immunologic , Enzyme Activation/immunology , HSP27 Heat-Shock Proteins , Humans , Interleukin-10/genetics , Lipopolysaccharides/immunology , Macrophage Activation/immunology , Mitogen-Activated Protein Kinases/metabolism , Mitogen-Activated Protein Kinases/physiology , Molecular Chaperones , Monocytes/enzymology , Neoplasm Proteins/metabolism , Neoplasm Proteins/pharmacology , RNA, Messenger/biosynthesis , p38 Mitogen-Activated Protein Kinases
18.
Mol Cell ; 6(3): 743-50, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11030354

ABSTRACT

The crystal structure of a dimeric 2:2:2 FGF:FGFR:heparin ternary complex at 3 A resolution has been determined. Within each 1:1 FGF:FGFR complex, heparin makes numerous contacts with both FGF and FGFR, thereby augmenting FGF-FGFR binding. Heparin also interacts with FGFR in the adjoining 1:1 FGF:FGFR complex to promote FGFR dimerization. The 6-O-sulfate group of heparin plays a pivotal role in mediating both interactions. The unexpected stoichiometry of heparin binding in the structure led us to propose a revised model for FGFR dimerization. Biochemical data in support of this model are also presented. This model provides a structural basis for FGFR activation by small molecule heparin analogs and may facilitate the design of heparin mimetics capable of modulating FGF signaling.


Subject(s)
Fibroblast Growth Factors/chemistry , Heparin/chemistry , Receptors, Fibroblast Growth Factor/chemistry , Binding Sites , Crystallography , Dimerization , Fibroblast Growth Factors/metabolism , Heparin/metabolism , Hydrogen Bonding , Molecular Sequence Data , Protein Structure, Tertiary , Receptors, Fibroblast Growth Factor/metabolism , Sulfates/chemistry , Sulfates/metabolism
19.
J Biochem ; 127(6): 1053-6, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10833274

ABSTRACT

Growth of Escherichia coli in the presence of glyphosate, an inhibitor of aromatic amino acid biosynthesis, has permitted the production of proton-dislocating ATPase that is specifically labeled with 5-fluorotryptophan. Five sets of (19)F resonances could be assigned to each tryptophan residue by lauryldimethylamine oxide and carboxypeptidase treatment. On labeling with 4-chloro-7-nitro-benzofurazan, the label attached to b155Lys, which is known to be in the catalytic site, which caused one of the residues, b108Trp, to become nonequivalent. (19)F NMR spectroscopic investigation of internally fluorotryptophan-labeled F(1)-ATPase will provide valuable information about the asymmetric nature of F(1)-ATPase and the conformational changes induced by ligand binding.


Subject(s)
Escherichia coli/enzymology , Proton-Translocating ATPases/metabolism , 4-Chloro-7-nitrobenzofurazan/chemistry , Carboxypeptidases/chemistry , Dimethylamines/chemistry , Fluorine , Glycine/analogs & derivatives , Glycine/pharmacology , Magnetic Resonance Spectroscopy , Proton-Translocating ATPases/biosynthesis , Tryptophan/antagonists & inhibitors , Tryptophan/metabolism , Glyphosate
20.
Clin Immunol ; 96(1): 52-66, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10873428

ABSTRACT

Depressed mitogen-induced IL-2 and IFN-gamma responses after severe mechanical or thermal injury are postulated to result from an expansion of Th2 lymphocytes with concomitant excessive production of IL-4 and/or IL-10. Here, we simultaneously assessed proliferation and Th1 (IFN-gamma) versus Th2 (IL-10, IL-4) lymphokine production in trauma patients' isolated T cells stimulated in a costimulation sufficient, antigen presenting cell independent system (anti CD3 + anti-CD4). T cells with depressed proliferation and IL-2 production simultaneously lost IL-4, IL-10, and IFN-gamma protein and mRNA responses. Exogenous IL-12 addition did not restore IFNgamma responses, but exogenous IL-2 partially restored IL-4, IFN-gamma, and IL-10 production. Although initially partially restored by exogenous IL-2 or stimulation with PMA + ionomycin, patient T cells with persisting anergy progressively lost even these lymphokine and proliferative responses. Development of global T cell anergy was not a result of lost T cell viability or protein synthesis, since it corresponded to predominance of anergic T cells with upregulated expression of CD11b, but downregulated CD28 and CD3 expression. Thus, the subset of posttrauma patients whose isolated T cells become unresponsive experienced progressively worsening global anergy, mediated not by an increased production of Th2 lymphokines, but possibly by T cell incapacity to be activated through TCR triggering or Ca(2+) mobilization.


Subject(s)
Burns/immunology , Clonal Anergy/immunology , Immune Tolerance/immunology , T-Lymphocytes, Helper-Inducer/immunology , Wounds and Injuries/immunology , Adult , Aged , Aged, 80 and over , CD28 Antigens/biosynthesis , Cell Division , Cells, Cultured , Down-Regulation , Female , Humans , Interferon-gamma/biosynthesis , Interferon-gamma/genetics , Interleukin-10/biosynthesis , Interleukin-10/genetics , Interleukin-2/biosynthesis , Interleukin-2/genetics , Interleukin-4/biosynthesis , Interleukin-4/genetics , Macrophage-1 Antigen/biosynthesis , Male , Middle Aged , RNA, Messenger/metabolism , Receptor-CD3 Complex, Antigen, T-Cell/genetics , T-Lymphocytes, Helper-Inducer/cytology
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