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1.
J Fungi (Basel) ; 9(12)2023 Dec 16.
Article in English | MEDLINE | ID: mdl-38132805

ABSTRACT

Marine fungi have been studied for a long history in many realms, but there are few reports on marine mushrooms. In this study, marine fungi with conspicuous subglobose sequestrate basidioma were discovered from mangrove forests in South China. They grow on the deadwood of mangroves in the intertidal zone, periodically submerging into seawater due to the tide. Some marine animals were observed to nest in their basidiomata or consume them as food. The pileus-gleba-inner veil complex (PGI) of the basidioma was observed to be detached from the stipe and transferred into seawater by external forces, and drifting on sea to spread spores after maturity. The detachment mechanism of their PGIs was revealed through detailed microscopic observations. The contrast culturing experiment using freshwater and seawater potato dextrose agar media showed they have probably obligately adapted to the marine environment. Based on morphological and molecular phylogenetic evidence, two new species of Candolleomyces (Basidiomycota, Agaricales), namely C. brunneovagabundus and C. albovagabundus, were described. They are similar and close to each other, but can be distinguished by the size and color of the basidioma, and the size of the basidiospores.

2.
J Tradit Chin Med ; 42(3): 472-478, 2022 06.
Article in English | MEDLINE | ID: mdl-35610019

ABSTRACT

OBJECTIVE: To explore the advantages of Traditional Chinese Medicine (TCM) in "prevention" and "control" of coronavirus disease 2019 (COVID-19) pandemic. METHODS: In this paper, we wish to estimate the effect on the virus transmission of scenarios assuming TCM were used to build the first defense line at the very early stage of the spread in Wuhan. We therefore first developed a classic susceptible infected removed (susceptible infected removed, SIR) transmission model based on the national data in China and then updated it to a TCM-SIR model to assess the potential impact of such assumptions, i.e. the underlying risk of lives lost and social economy loss. RESULTS: (a) With the nationwide community lockdown, the risk value was from 90 000 to 250 000 without TCM intervention and the risk value was from 70 000 to 220 000 with TCM intervention; (b) Based the risk assessment method, we forecasted that the infections peak would be 58016 without TCM intervention, which happened on February 17 2020. However, the infections peak would be 45713 with TCM intervention, which happened on 16 February 2020. CONCLUSIONS: The adoption of nationwide community lockdown is conducive to timely control the epidemic and protect people's lives and safety. At the same time, we can get lower infections if TCM intervention can be considered. We can also get the benefits from TCM prevention of COVID-19 pandemic by the basic number of infections.


Subject(s)
COVID-19 , Drugs, Chinese Herbal , China , Communicable Disease Control , Drugs, Chinese Herbal/therapeutic use , Humans , Medicine, Chinese Traditional , Pandemics , Risk Assessment , SARS-CoV-2
3.
Front Surg ; 9: 814531, 2022.
Article in English | MEDLINE | ID: mdl-35419406

ABSTRACT

Lumbar disc herniation is among the common phenotypes of degenerative lumbar spine diseases, significantly affecting patients' quality of life. The practice pattern is diverse. Choosing conservative measures or surgical treatments is still controversial in some areas. For those who have failed conservative treatment, surgery with or without instrumentation is recommended, causing significant expenditures and frustrating complications, that should not be ignored. In the article, we performed a literature review and summarized the evidence by subheadings to unravel the cons of surgical intervention for lumbar disc herniation. There are tetrad critical issues about surgical treatment of lumbar disc herniation, i.e., favorable natural history, insufficient evidence in a recommendation of fusion surgery for patients, metallosis, and implant removal. Firstly, accumulating evidence reveals immune privilege and auto-immunity hallmarks of human lumbar discs within the closed niche. Progenitor cells within human discs further expand the capacity with the endogenous repair. Clinical watchful follow-up studies with repeated diagnostic imaging reveal spontaneous resolution for lumbar disc herniation, even calcified tissues. Secondly, emerging evidence indicates long-term complications of lumbar fusion, such as adjacent segment disease, pseudarthrosis, implant failure, and sagittal spinal imbalance, which get increasing attention. Thirdly, systemic and local reactions (metallosis) for metal instrumentation have been noted with long-term health concerns and toxicity. Fourthly, the indications and timing for spinal implant removal have not reached a consensus. Other challenging issues include postoperative lumbar stiffness. The review provided evidence from a negative perspective for surgeons and patients who attempt to choose surgical treatment. Collectively, the emerging underlying evidence questions the benefits of traditional surgery for patients with lumbar disc herniation. Therefore, the long-term effects of surgery should be closely observed. Surgical decisions should be made prudently for each patient.

4.
J Pharmacol Exp Ther ; 378(3): 197-206, 2021 09.
Article in English | MEDLINE | ID: mdl-34215702

ABSTRACT

Phosphorylation of the eukaryotic translation initiation factor 2 α-subunit, which subsequently upregulates activating transcription factor 4 (ATF4), is the core event in the integrated stress response (ISR) pathway. Previous studies indicate phosphorylation of eukaryotic translation initiation factor 2 ɑ-subunit in atrial tissue in response to atrial fibrillation (AF). This study investigated the role of ISR pathway in experimental AF by using a small-molecule ISR inhibitor (ISRIB). Accordingly, rats were subjected to coronary artery occlusion to induce myocardial infarction (MI), or sham operation, and received either trans-ISRIB (2 mg/kg/d, i.p.) or vehicle for seven days. Thereafter, animals were subjected to the AF inducibility test by transesophageal rapid burst pacing followed by procurement of left atrium (LA) for assessment of atrial fibrosis, inflammatory indices, autophagy-related proteins, ISR activation, ion channel, and connexin 43 expression. Results showed a significant increase in the AF vulnerability and the activation of ISR in LA as evidenced by enhanced eukaryotic translation initiation factor 2 ɑ-subunit phosphorylation. ISRIB treatment suppressed upregulation of ATF4, fibrosis as indexed by determination of α-smooth muscle actin and collagen levels, inflammatory macrophage infiltration (i.e., CD68 and inducible nitric oxide synthase/CD68-positive macrophage), and autophagy as determined by expression of light chain 3. Further, ISRIB treatment reversed the expression of relevant ion channel (i.e., the voltage-gated sodium channel 1.5 , L-type voltage-dependent calcium channel 1.2, and voltage-activated A-type potassium ion channel 4.3) and connexin 43 remodeling. Collectively, the results suggest that the ISR is a key pathway in pathogenesis of AF, post-MI, and represents a novel target for treatment of AF. SIGNIFICANCE STATEMENT: The activation of integrated stress response (ISR) pathway as evidenced by enhanced eukaryotic translation initiation factor 2 ɑ-subunit phosphorylation in left atrium plays a key role in atrial fibrillation (AF). ISR inhibitor (ISRIB) reduces AF occurrence and atrial proarrhythmogenic substrate. The beneficial action of ISRIB may be mediated by suppressing ISR pathway-related cardiac fibrosis, inflammatory macrophage infiltration, autophagy, and restoring the expression of ion channel and connexin 43. This study suggests a key dysfunctional role for ISR in pathogenesis of AF with implications for novel treatment.


Subject(s)
Atrial Fibrillation , Animals , Heart Atria , Phosphorylation , Rats
5.
Pharmazie ; 74(5): 301-304, 2019 05 01.
Article in English | MEDLINE | ID: mdl-31109401

ABSTRACT

Angiogenin (ANG) is known to alter multiple cell behaviors by directly targeting downstream targets, but its role in hepatocellular carcinoma (HCC) remains to be elucidated. The expression of ANG in HCC cell lines was measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. The effects of ANG expression on cell proliferation, cell migration, and hallmarks of epithelial-mesenchymal transition (EMT) process were also investigated. The relationship between ANG and high mobility group AT-hook 2 (HMGA2) was evaluated. ANG expression was increased in HCC cell lines. Downregulating of ANG inhibits proliferation, migration, and EMT of HCC cells. The direct regulation of ANG on HMGA2 was verified by luciferase activity reporter assay and western blot assay. Furthermore, overexpression of HMGA2 reversed the inhibitory effects of ANG downregulation on HCC cell behaviors. Our results illustrated the mechanism that ANG promote the EMT of HCC through targeting HMGA2.


Subject(s)
Carcinoma, Hepatocellular/metabolism , HMGA2 Protein/metabolism , Liver Neoplasms/metabolism , Ribonuclease, Pancreatic/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Movement/physiology , Cell Proliferation/physiology , Down-Regulation , Epithelial-Mesenchymal Transition , Humans , Liver Neoplasms/pathology , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Ribonuclease, Pancreatic/biosynthesis , Ribonuclease, Pancreatic/genetics , Transfection , Up-Regulation
7.
Liver Int ; 36(10): 1525-34, 2016 10.
Article in English | MEDLINE | ID: mdl-27028410

ABSTRACT

BACKGROUND: This study aimed to investigate the possible synergistic effects of lipid disorder with renin-angiotensin system (RAS) activation in non-alcoholic fatty liver disease (NAFLD). METHODS: Apolipoprotein E gene-knockout mice, angiotensin II (Ang II) type 1 receptor (AT1) gene-knockout mice and human hepatoblastoma cell line (HepG2) were used for experiments. Lipid accumulation was examined by Filipin staining and intracellular cholesterol quantitative assay. The gene and protein expression of molecules involved in RAS and low-density lipoprotein receptor (LDLr) pathway was examined by real-time PCR, immunofluorescent staining and Western blot. RESULTS: There was significantly increased expression of RAS components and extracellular matrix (ECM) in livers of high-fat-diet-fed apolipoprotein E gene-knockout mice compared with controls. Upregulation of RAS components was positively associated with increased plasma levels of lipid profile. The in vitro study further confirmed that cholesterol loading increased supernatant renin activity and Ang II level of HepG2 cells, accompanied by increased ECM production that was positively associated with increased expression of intracellular RAS components. Interestingly, Ang II treatment increased lipid accumulation in livers of C57BL/6 mice and HepG2 cells. Furthermore, Ang II treatment increased gene and protein expression of sterol regulatory element-binding protein (SREBP) cleavage activating protein (SCAP), SREBP-2 and LDLr, which were mediated by enhanced SCAP/SREBP-2 complex translocation from endoplasmic reticulum to Golgi. However, LDLr pathway was accordingly downregulated in livers of AT1 gene-knockout C57BL/6 mice or in HepG2 cells treated by telmisartan. CONCLUSION: These findings demonstrate that lipid disorder and intrahepatic RAS activation synergistically accelerate NAFLD progression.


Subject(s)
Dyslipidemias/physiopathology , Extracellular Matrix/metabolism , Non-alcoholic Fatty Liver Disease/physiopathology , Receptors, LDL/metabolism , Renin-Angiotensin System , Angiotensin II/metabolism , Angiotensin II/pharmacology , Animals , Benzimidazoles/pharmacology , Benzoates/pharmacology , Cholesterol/metabolism , Diet, High-Fat , Hep G2 Cells , Humans , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Lipid Metabolism/drug effects , Male , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptor, Angiotensin, Type 1/genetics , Signal Transduction , Sterol Regulatory Element Binding Protein 2/genetics , Sterol Regulatory Element Binding Protein 2/metabolism , Telmisartan
8.
Ann Oncol ; 22(2): 468-71, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20624787

ABSTRACT

BACKGROUND: Children with recurrent or refractory malignant lymphoma generally have a poor prognosis. There is a need for new active drug combinations for this high-risk group of patients. PATIENTS AND METHODS: This study evaluated the activity and toxicity of the methotrexate, ifosfamide, etoposide and dexamethasone (MIED) regimen for childhood refractory/recurrent non-Hodgkin's lymphoma (NHL) or Hodgkin's lymphoma (HL). From 1991 through 2006, 62 children with refractory/recurrent NHL (n = 24) or HL (n = 38) received one to six cycles of MIED. Based on MIED response, intensification with hematopoietic stem cell transplantation (HSCT) was considered. RESULTS: There were 10 complete (CR) and 5 partial responses (PR) among the 24 children with NHL [combined response rate, 63%; 95% confidence interval (CI) 38% to 73%]. There were 13 CR and 18 PR among the 37 assessable children with HL (combined response rate, 84%; 95% CI, 68% to 94%). Although 59% courses were associated with grade IV neutropenia, treatment was well tolerated and without toxic deaths. CONCLUSIONS: MIED is an effective regimen for refractory/recurrent childhood malignant lymphoma, permitting a bridge to intensification therapy with HSCT.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hodgkin Disease/drug therapy , Lymphoma, Non-Hodgkin/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Child , Dexamethasone/administration & dosage , Etoposide/administration & dosage , Hodgkin Disease/pathology , Humans , Ifosfamide/administration & dosage , Lymphoma, Non-Hodgkin/pathology , Methotrexate/administration & dosage , Recurrence , Salvage Therapy
9.
Am J Physiol Heart Circ Physiol ; 298(6): H1646-51, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20348217

ABSTRACT

Inflammatory stress accelerates the progression of atherosclerosis. Sirolimus, a new immunosuppressive agent, has been shown to have pleiotropic antiatherosclerotic effects. In this study we hypothesized that sirolimus inhibits 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR)-mediated cholesterol synthesis in human vascular smooth muscle cells (VSMCs) under inflammatory stress. Using radioactive assay, we demonstrated that sirolimus inhibited the increase of interleukin-1beta (IL-1beta)-induced cholesterol synthesis in VSMCs. Further studies showed that sirolimus inhibited both the HMGR gene and protein expression in VSMCs treated with or without IL-1beta. These effects were mediated by inhibiting the gene expression of sterol regulatory element-binding protein-2 (SREBP-2) and SREBP-2 cleavage-activating protein (SCAP) as checked by real-time PCR, Western blot analysis, and confocal microscopy for the observation of decreased protein translocation of the SCAP/SREBP-2 complex from the endoplasmic reticulum (ER) to the Golgi. Insulin-induced gene-1 (Insig-1) is a key ER protein controlling the feedback regulation of HMGR at transcriptional and posttranscriptional levels. We demonstrated that sirolimus increased Insig-1 expression which may bind to the SCAP, preventing the exit of SCAP-SREBP complexes from the ER. The increased Insig-1 also accelerated HMGR protein degradation in VSMCs as shown by pulse-chase analysis. In conclusion, sirolimus inhibits cholesterol synthesis induced by inflammatory stress through the downregulation of HMGR expression and the acceleration of HMGR protein degradation. These findings may improve our understanding of the molecular mechanisms of the antiatherosclerosis properties of sirolimus.


Subject(s)
Cholesterol/metabolism , Immunosuppressive Agents/pharmacology , Inflammation/metabolism , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Sirolimus/pharmacology , Acyl Coenzyme A/metabolism , Atherosclerosis/prevention & control , Cells, Cultured , Coronary Vessels/drug effects , Coronary Vessels/metabolism , Coronary Vessels/pathology , Endoplasmic Reticulum/metabolism , Golgi Apparatus/metabolism , Humans , Inflammation/pathology , Interleukin-1beta/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Muscle, Smooth, Vascular/pathology , Sterol Regulatory Element Binding Protein 2/metabolism
10.
Leukemia ; 24(2): 371-82, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20010620

ABSTRACT

We analyzed the long-term outcome of 1011 patients treated in five successive clinical trials (Total Therapy Studies 11, 12, 13A, 13B, and 14) between 1984 and 1999. The event-free survival improved significantly (P=0.003) from the first two trials conducted in the 1980s to the three more recent trials conducted in the 1990s. Approximately 75% of patients treated in the 1980s and 80% in the 1990s were cured. Early intensive triple intrathecal therapy, together with more effective systemic therapy, including consolidation and reinduction treatment (Studies 13A and 13B) as well as dexamethasone (Study 13B), resulted in a very low rate of isolated central nervous system (CNS) relapse rate (<2%), despite the reduced use of cranial irradiation. Factors consistently associated with treatment outcome were age, leukocyte count, immunophenotype, DNA index, and minimal residual disease level after remission induction treatment. Owing to concerns about therapy-related secondary myeloid leukemia and brain tumors, in our current trials we reserve the use of etoposide for patients with refractory or relapsed leukemia undergoing hematopoietic stem cell transplantation, and cranial irradiation for those with CNS relapse. The next main challenge is to further increase cure rates while improving quality of life for all patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Recurrence, Local/therapy , Neoplasms, Second Primary/therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Adolescent , Child , Child, Preschool , Chromosome Aberrations , Combined Modality Therapy , Cranial Irradiation , Female , Follow-Up Studies , Humans , Immunophenotyping , Infant , Injections, Spinal , Male , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Neoplasm, Residual , Neoplasms, Second Primary/genetics , Neoplasms, Second Primary/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Prognosis , Remission Induction , Risk Factors , Survival Rate , Time Factors , Treatment Outcome
11.
Hepatology ; 48(3): 770-81, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18752326

ABSTRACT

UNLABELLED: The prevailing theory in non-alcoholic fatty liver disease (NAFLD) is the "two-hit" hypothesis. The first hit mainly consists of lipid accumulation, and the second is subsequent systemic inflammation. The current study was undertaken to investigate whether inflammatory stress exacerbates lipid accumulation in liver and its underlying mechanisms. We used interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) stimulation in human hepatoblastoma cell line (HepG2) cells and primary hepatocytes in vitro, and casein injection in apolipoprotein E knockout mice in vivo to induce inflammatory stress. The effects of inflammatory stress on cholesterol accumulation were examined by histochemical staining and a quantitative intracellular cholesterol assay. The gene and protein expressions of molecules involved in cholesterol trafficking were examined by real-time polymerase chain reaction (PCR) and western blot. Cytokine production in the plasma of apolipoprotein E knockout mice was measured by enzyme-linked immunosorbent assay. Our results showed that inflammatory stress increased cholesterol accumulation in hepatic cells and in the livers of apolipoprotein E knockout mice. Further analysis showed that inflammatory stress increased the expression of low-density lipoprotein (LDL) receptor (LDLr), sterol regulatory element-binding protein (SREBP) cleavage activating protein (SCAP), and SREBP-2. Confocal microscopy showed that IL-1beta increased the translocation of SCAP/SREBP-2 complex from endoplasmic reticulum (ER) to Golgi in HepG2 cells, thereby activating LDLr gene transcription. IL-1beta, TNF-alpha, and systemic inflammation induced by casein injection also inhibited expression of adenosine triphosphate-binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor-alpha (PPAR-alpha), and liver X receptor-alpha (LXRalpha). This inhibitory effect may cause cholesterol efflux reduction. CONCLUSION: Inflammatory stress up-regulates LDLr-mediated cholesterol influx and down-regulates ABCA1-mediated cholesterol efflux in vivo and in vitro. This may exacerbate the progression of NAFLD by disrupting cholesterol trafficking control, especially during the second hit phase of liver damage.


Subject(s)
Cholesterol/metabolism , Fatty Liver/metabolism , Hepatocytes/metabolism , Inflammation/metabolism , Lipid Metabolism/physiology , ATP Binding Cassette Transporter 1 , ATP-Binding Cassette Transporters/metabolism , Animals , Apolipoproteins E/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , DNA-Binding Proteins/metabolism , Disease Models, Animal , Fatty Liver/pathology , Hepatocytes/drug effects , Hepatocytes/pathology , Humans , Inflammation/chemically induced , Inflammation/pathology , Interleukin-1beta/adverse effects , Lipid Metabolism/drug effects , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Liver X Receptors , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Orphan Nuclear Receptors , PPAR alpha/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Receptors, LDL/metabolism , Tumor Necrosis Factor-alpha/adverse effects
13.
Transplantation ; 84(8): 1029-36, 2007 Oct 27.
Article in English | MEDLINE | ID: mdl-17989609

ABSTRACT

BACKGROUND: Sirolimus is a potent immunosuppressive agent, which is associated with dyslipidemia in clinical transplantation. The present study was undertaken to investigate the potential hepatocyte mechanisms by which sirolimus causes dyslipidemia. METHODS: Using both a quantitative assay of intracellular cholesterol and an [3H]-labeled cholesterol efflux assay, we studied the effect of sirolimus on cholesterol accumulation and cholesterol efflux in HepG2 cells in the absence or presence of inflammatory stress induced by interleukin-1beta. The gene and protein expression of molecules involved in cholesterol homeostasis were examined by real-time reverse-transcription polymerase chain reaction and Western blotting. RESULTS: Sirolimus inhibited low-density lipoprotein (LDL) receptor (LDLr)-mediated cholesterol ester accumulation induced by interleukin-1beta in HepG2 cells. This inhibitory effect was mediated by down-regulation of sterol regulatory element-binding proteins (SREBP) cleavage activating protein (SCAP) and SREBP-2 mRNA expression. Using confocal microscopy, we demonstrated that sirolimus reduced translocation of SCAP-SREBP2 complex from endoplasmic reticulum to Golgi for activation, thereby inhibiting LDLr gene transcription. Reduction of LDLr in the liver may result in a delay of LDL-cholesterol clearance from circulation causing an increase of plasma cholesterol concentration. Furthermore, sirolimus increased cholesterol efflux mediated by adenosine triphosphate-binding cassette transporter A1 gene expression by increasing peroxisome proliferator-activated receptor-alpha and liver X receptor-alpha gene and protein expression. Increased cholesterol efflux from HepG2 cells may increase high-density lipoprotein cholesterol level and also contribute to apolipoprotein B lipoprotein formation by enhancing transfer of high-density lipoprotein cholesterol to apolipoprotein B lipoproteins. CONCLUSIONS: This study demonstrates that the increase of LDL cholesterol by sirolimus is partly due to the reduction of LDLr on hepatocytes.


Subject(s)
Cholesterol, LDL/metabolism , Dyslipidemias/chemically induced , Hepatocytes/drug effects , Immunosuppressive Agents/pharmacology , Receptors, LDL/antagonists & inhibitors , Sirolimus/pharmacology , Cell Line , Dyslipidemias/metabolism , Endoplasmic Reticulum/chemistry , Endoplasmic Reticulum/metabolism , Golgi Apparatus/chemistry , Golgi Apparatus/metabolism , Hepatocytes/metabolism , Homeostasis/drug effects , Humans , Immunosuppressive Agents/adverse effects , Intracellular Signaling Peptides and Proteins/analysis , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/analysis , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/metabolism , Protein Transport , RNA, Messenger/analysis , RNA, Messenger/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism , Sirolimus/adverse effects , Sterol Regulatory Element Binding Protein 2/analysis , Sterol Regulatory Element Binding Protein 2/antagonists & inhibitors , Sterol Regulatory Element Binding Protein 2/metabolism
14.
AJNR Am J Neuroradiol ; 28(4): 603-7, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17416804

ABSTRACT

As an essential part of the National Cancer Institute (NCI)-funded Pediatric Brain Tumor Consortium (PBTC), the Neuroimaging Center (NIC) is dedicated to infusing the study of pediatric brain tumors with imaging "best practice" by producing a correlative research plan that 1) resonates with novel therapeutic interventions being developed by the wider PBTC, 2) ensures that every PBTC protocol incorporates an imaging "end point" among its objectives, 3) promotes the widespread implementation of standardized technical protocols for neuroimaging, and 4) facilitates a quality assurance program that complies with the highest standards for image data transfer, diagnostic image quality, and data integrity. To accomplish these specific objectives, the NIC works with the various PBTC sites (10 in all, plus NCI/ National Institute of Neurological Diseases and Stroke representation) to ensure that the overarching mission of the consortium--to better understand tumor biology and develop new therapies for central nervous system tumors in children--is furthered by creating a uniform body of imaging techniques, technical protocols, and standards. Since the inception of the NIC in 2003, this broader mandate has been largely accomplished through a series of site visits and meetings aimed at assessing prevailing neuroimaging practices against NIC-recommended protocols, techniques, and strategies for achieving superior image quality and executing the secure transfer of data to the central PBTC. These ongoing evaluations periodically examine investigations into targeted drug therapies. In the future, the NIC will concentrate its efforts on improving image analysis for MR imaging and positron-emission tomography (PET) and on developing new ligands for PET; imaging markers for radiation therapy; and novel systemic, intrathecal, and intralesional therapeutic interventions.


Subject(s)
Brain Neoplasms/diagnosis , Magnetic Resonance Imaging , Multicenter Studies as Topic , Positron-Emission Tomography , Biomedical Research/organization & administration , Child , Humans , National Institutes of Health (U.S.) , United States
15.
Am J Physiol Heart Circ Physiol ; 292(6): H2721-8, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17322416

ABSTRACT

Sirolimus is a potent immunosuppressive agent and has an anti-atherosclerotic effect through its anti-proliferative property. The present study was undertaken to investigate the effect of sirolimus on intracellular cholesterol homeostasis in human vascular smooth muscle cells (VSMCs) in the presence of inflammatory cytokine IL-1 beta. We explored the effect of sirolimus on the lipid accumulation of VSMCs in the presence of IL-1 beta, using Oil Red O staining and quantitative measurement of intracellular cholesterol. The effect of sirolimus on the gene and protein expression of lipoprotein receptors and ATP binding cassettes (ABCA1 and ABCG1) was examined by real-time PCR and Western blotting, respectively. Furthermore, the effect of sirolimus on cholesterol efflux from VSMCs in the presence or absence of IL-1 beta was also investigated using [(3)H] cholesterol efflux. Finally, we examined the effect of sirolimus on the production of inflammatory cytokines in VSMCs using ELISA. Sirolimus reduced intracellular lipid accumulation in VSMCs mediated by IL-1 beta possibly due to the reduction of expression of low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) receptors. Sirolimus increased cholesterol efflux from VSMCs and overrode the suppression of cholesterol efflux induced by IL-1 beta. Sirolimus also increased ABCA1 and ABCG1 genes expression, even in the presence of IL-1 beta. We further confirmed that sirolimus inhibited mRNA and protein expression of inflammatory cytokines IL-6, tumor necrosis factor-alpha, IL-8, and monocyte chemoattractant protein-1. Inhibition of lipid uptake together with increasing cholesterol efflux and the inhibition of inflammatory cytokines are all important aspects of the anti-atherosclerotic effects of sirolimus on VSMCs.


Subject(s)
Atherosclerosis/prevention & control , Cardiovascular Agents/pharmacology , Cholesterol/metabolism , Inflammation/prevention & control , Muscle, Smooth, Vascular/drug effects , Myocytes, Smooth Muscle/drug effects , Sirolimus/pharmacology , ATP Binding Cassette Transporter 1 , ATP Binding Cassette Transporter, Subfamily G, Member 1 , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Atherosclerosis/genetics , Atherosclerosis/metabolism , Azo Compounds , Cardiovascular Agents/therapeutic use , Cells, Cultured , Coloring Agents , Coronary Vessels/cytology , Coronary Vessels/drug effects , Coronary Vessels/metabolism , Cytokines/genetics , Cytokines/metabolism , Dose-Response Relationship, Drug , Gene Expression/drug effects , Homeostasis/drug effects , Humans , Inflammation/genetics , Inflammation/metabolism , Interleukin-1beta/metabolism , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , RNA, Messenger/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism , Sirolimus/therapeutic use , Staining and Labeling/methods
16.
Arterioscler Thromb Vasc Biol ; 26(5): 1150-5, 2006 May.
Article in English | MEDLINE | ID: mdl-16543490

ABSTRACT

OBJECTIVE: Although inflammation is a recognized feature of atherosclerosis, the impact of inflammation on cellular cholesterol homeostasis is unclear. This study focuses on the molecular mechanisms by which inflammatory cytokines disrupt low-density lipoprotein (LDL) receptor regulation. METHODS AND RESULTS: IL-1beta enhanced transformation of vascular smooth muscle cells into foam cells by increasing uptake of unmodified LDL via LDL receptors and by enhancing cholesterol esterification as demonstrated by Oil Red O staining and direct assay of intracellular cholesterol concentrations. In the absence of IL-1beta, a high concentration of LDL decreased LDL receptor promoter activity, mRNA synthesis and protein expression. However, IL-1beta enhanced LDL receptor expression, overriding the suppression usually induced by a high concentration of LDL and inappropriately increasing LDL uptake. Exposure to IL-1beta also caused overexpression of the sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), and enhanced its translocation from the endoplasmic reticulum to the Golgi, where it is known to cleave SREBP, thereby enhancing LDL receptor gene expression. CONCLUSIONS: These observations demonstrate that IL-1beta disrupts cholesterol-mediated LDL receptor feedback regulation, permitting intracellular accumulation of unmodified LDL and causing foam cell formation. The implication of these findings is that inflammatory cytokines may contribute to intracellular LDL accumulation without previous modification of the lipoprotein.


Subject(s)
Gene Expression Regulation/drug effects , Interleukin-1/pharmacology , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , Receptors, LDL/genetics , Cells, Cultured , Endoplasmic Reticulum/metabolism , Humans , Intracellular Signaling Peptides and Proteins , Lipoproteins, LDL/metabolism , Membrane Proteins/metabolism , Promoter Regions, Genetic , Sterol O-Acyltransferase/genetics , Sterol O-Acyltransferase/metabolism , Sterol Regulatory Element Binding Proteins/metabolism
17.
Clin Oncol (R Coll Radiol) ; 16(3): 215-22, 2004 May.
Article in English | MEDLINE | ID: mdl-15191011

ABSTRACT

AIMS: We have evaluated the potential for intensity-modulated radiation therapy (IMRT) to reduce dose to surrounding normal tissues in children with retinoblastoma confined to the globe of the eye. MATERIALS AND METHODS: Treatment planning computed tomography (CT) scans from five children were used for comparison of four radiotherapy techniques to treat the eye. IMRT, conformal, anterior-lateral photon and en face electron plans were generated using the Corvus (NOMOS) and PLUNC treatment planning systems. Doses to surrounding critical structures were compared after normalisation of target coverage. RESULTS: The IMRT treatment technique allowed the greatest sparing of the surrounding bony orbit, with an average of 60% of the ipsilateral bony orbit treated above 20 Gy and 48% treated above 24 Gy when 45 Gy is prescribed to the globe. IMRT techniques reduced dose to the surrounding bony orbit by more than one-third compared with anterior-lateral photon and electron techniques, and by 23% compared with conformal techniques. The application of IMRT also reduced dose to other surrounding normal tissues, including the temporal lobe and contralateral orbit. CONCLUSION: IMRT shows potential for protecting normal tissues in patients requiring external beam radiation therapy for retinoblastoma.


Subject(s)
Eye Neoplasms/radiotherapy , Retinoblastoma/radiotherapy , Child , Dose Fractionation, Radiation , Humans , Orbit/radiation effects , Radiation Injuries/prevention & control , Radiotherapy, Conformal , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
18.
Cancer ; 92(6): 1613-20, 2001 Sep 15.
Article in English | MEDLINE | ID: mdl-11745240

ABSTRACT

BACKGROUND: Approximately 5-10% of patients with rhabdomyosarcomas (RMS) are diagnosed during the first year of life, and their clinical characteristics have been well documented. However, because RMS rarely occurs during the neonatal period, little is known about neonatal RMS. METHODS: Four patients with neonatal RMS were treated at St. Jude Children's Research Hospital between 1962 and 1999. The authors report the results of a review of these patients and of cases described in the literature. Clinical, radiologic, and pathologic features of these patients and their outcomes were evaluated. RESULTS: One patient with embryonal RMS was treated successfully with a combination of systemic chemotherapy and local control measures. The other three patients had alveolar RMS. Two of them had multiple skin and subcutaneous metastatic nodules at the time of diagnosis and developed brain metastases early in their course. In one of these patients, the PAX3-FKHR fusion transcript was detected. Three other similar cases of neonatal alveolar RMS with metastases to the skin and brain have been reported in the literature. CONCLUSIONS: A distinct syndrome of neonatal RMS is described. This syndrome is characterized by alveolar histology, multiple skin and subcutaneous metastases, and fatal outcome as the result of early brain metastasis.


Subject(s)
Brain Neoplasms/secondary , Rhabdomyosarcoma, Alveolar/pathology , Skin Neoplasms/secondary , Soft Tissue Neoplasms/pathology , Female , Humans , Infant, Newborn , Male , Radiography , Rhabdomyosarcoma, Alveolar/congenital , Rhabdomyosarcoma, Alveolar/diagnostic imaging , Skin Neoplasms/pathology , Soft Tissue Neoplasms/congenital , Soft Tissue Neoplasms/diagnostic imaging
19.
Cancer ; 92(7): 1959-66, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11745271

ABSTRACT

BACKGROUND: The objective of this report was to determine the cumulative incidence of and risk factors for second malignancy and the competing risk of death due to any other cause among patients who were treated for childhood non-Hodgkin lymphoma (NHL). METHODS: The authors retrospectively reviewed a cohort of 497 patients with NHL who were treated at St. Jude Children's Research Hospital between 1970 and 1997. RESULTS: A second malignancy developed in 16 patients (9 patients with solid tumors and 7 patients with secondary acute myeloid leukemia [AML]). This number was 10.8-fold (95% confidence interval, 6.1-16.9) higher than the 1.48 patients projected for the general population by SEER Cancer Statistics. The estimated cumulative incidence rate of second malignancy was 2.1% +/- 0.7% at 10 years after diagnosis of NHL and increased to 4.8% +/- 1.3% at 20 years after diagnosis. The cumulative incidence rate of second malignancy was least among patients with small noncleaved cell lymphoma (0.5% +/- 0.5% at 20 years), higher among patients with large cell lymphoma (5.8% +/- 3.3% at 20 years), and highest among patients with lymphoblastic lymphoma (10.9% +/- 3.6% at 20 years; P = 0.002 for overall comparison). Exposure to epipodophyllotoxins was a risk factor for the development of secondary AML (P < 0.001). The cumulative incidence rate of death due to other causes was significantly less for patients who were treated after June 1978 (19.9% +/- 2.2% at 10 years) compared with patients who were treated earlier (55.6% +/- 4.2% at 10 years; P < 0.001), whereas the risk of second malignancy was similar for these two eras. CONCLUSIONS: Survivors of childhood NHL, especially those with lymphoblastic histology, are at a greater risk of developing a second malignancy compared with the general population. The incidence rate of second malignancy has remained unchanged despite a recent decline in the risk of death related to primary NHL or earlier treatment complications.


Subject(s)
Lymphoma, Non-Hodgkin/therapy , Neoplasms, Second Primary/epidemiology , Adolescent , Adult , Antineoplastic Agents, Phytogenic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Child , Combined Modality Therapy , Female , Humans , Incidence , Male , Podophyllotoxin/therapeutic use , Retrospective Studies , Risk Factors , Survivors
20.
Pediatr Neurosurg ; 35(5): 225-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11741114

ABSTRACT

The extent of brain tumor resection affects survival. Second-look surgery (resection of residual tumor before radiographic progression) may improve survival by reducing the tumor burden, but the morbidity of the procedure is not known. On chart review of 280 patients with two or more brain tumor operations treated between January 1985 and June 1998, we identified 47 patients with second-look surgery. Lansky and Eastern Cooperative Oncology Group (ECOG) performance scores, as well as perioperative complications were recorded. There were 21 gliomas (6 malignant), 12 medulloblastomas, 3 craniopharyngiomas, 3 ependymomas and 8 miscellaneous tumors. Median time to second surgery was 50 days. Perioperative complications occurred in 45% of patients. There was no significant change in the mean Lansky and ECOG scores 4 and 24 weeks after surgery. Gross total resection (GTR) was achieved in 62% of patients and near total resection (NTR) in 23%, and 15% of patients had subtotal resection. GTR or NTR was achieved in 66% of medulloblastomas and 100% of gliomas. We conclude that second-look surgery by experienced pediatric neurosurgeons has an acceptable morbidity and should be considered in patients with residual tumors.


Subject(s)
Brain Neoplasms/surgery , Central Nervous System Diseases/diagnosis , Neoplasm, Residual/surgery , Postoperative Complications/diagnosis , Spinal Cord Neoplasms/surgery , Brain Neoplasms/diagnosis , Child , Humans , Neoplasm, Residual/diagnosis , Neurologic Examination , Prognosis , Reoperation , Retrospective Studies , Risk Factors , Spinal Cord Neoplasms/diagnosis
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