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1.
Ann R Coll Surg Engl ; 103(7): 478-480, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34192500

ABSTRACT

BACKGROUND: There is limited evidence on perioperative outcomes of surgical patients during the COVID-19 pandemic to inform continued operating into the winter period. METHODS: We retrospectively analysed the rate of 30-day COVID-19 transmission and mortality of all surgical patients in the three hospitals in our trust in the East of England during the first lockdown in March 2020. All patients who underwent a swab were swabbed on or 24 hours prior to admission. RESULTS: There were 4,254 patients and an overall 30-day mortality of 0.99%. The excess surgical mortality in our region was 0.29%. There were 39 patients who were COVID-19 positive within 30 days of admission, 12 of whom died. All 12 were emergency admissions with a length of stay longer than 24 hours. There were three deaths among those who underwent day case surgery, one of whom was COVID-19 negative, and the other two were not swabbed but not suspected to have COVID-19. There were two COVID-19 positive elective cases and none in day case elective or emergency surgery. There were no COVID-19 positive deaths in elective or day case surgery. CONCLUSIONS: There was a low rate of COVID-19 transmission and mortality in elective and day case operations. Our data have allowed us to guide patients in the consent process and provided the evidence base to restart elective and day case operating with precautions and regular review. A number of regions will be similarly affected and should perform a review of their data for the winter period and beyond.


Subject(s)
Ambulatory Surgical Procedures/mortality , COVID-19/epidemiology , Elective Surgical Procedures/mortality , Emergency Treatment/mortality , Ambulatory Surgical Procedures/standards , Ambulatory Surgical Procedures/statistics & numerical data , COVID-19/complications , COVID-19/diagnosis , COVID-19/transmission , COVID-19 Testing/standards , COVID-19 Testing/statistics & numerical data , Elective Surgical Procedures/standards , Elective Surgical Procedures/statistics & numerical data , Emergency Service, Hospital/standards , Emergency Service, Hospital/statistics & numerical data , Emergency Treatment/standards , Emergency Treatment/statistics & numerical data , England/epidemiology , Female , Hospital Mortality , Humans , Incidence , Infection Control/standards , Infection Control/statistics & numerical data , Length of Stay/statistics & numerical data , Male , Pandemics/prevention & control , Pandemics/statistics & numerical data , Patient Admission/standards , Patient Admission/statistics & numerical data , Retrospective Studies , SARS-CoV-2/isolation & purification , State Medicine/standards , State Medicine/statistics & numerical data
2.
Int J Surg Case Rep ; 71: 222-224, 2020.
Article in English | MEDLINE | ID: mdl-32480329

ABSTRACT

INTRODUCTION: Isolated pancreatic body transection secondary to blunt abdominal trauma is a very rare injury associated with poor outcomes. Almost all previously reported cases were managed by emergency distal pancreatectomy, which is associated with high morbidity and mortality. To our knowledge, this is the first reported case of complete transection of the pancreas at the body that was successfully treated by conservative management in an adult patient. PRESENTATION OF CASE: A 19-year-old male was found to have complete transection of the pancreatic body on computed tomography (CT) following blunt force abdominal trauma. Given that he was haemodynamically stable without evidence of haemorrhage or bile leakage on imaging, a trial of conservative management was initiated. He remained well through his admission, gradually improving clinically and biochemically with stable appearances on serial imaging. He remains asymptomatic as of six months since discharge from the hospital and continues to be monitored in the outpatient setting. DISCUSSION: Management of pancreatic trauma with ductal injury has typically been with emergency distal pancreatectomy, which is associated with high morbidity and mortality. The decision to operate should not be purely based on radiological findings, and should take into account clinical status, haemodynamic stability, coexisting injuries and evidence of active haemorrhage or bile leak. CONCLUSION: In select cases, it is reasonable to trial conservative management in isolated traumatic pancreatic body fracture by means of close clinical observation and serial imaging. This may allow the patient to avoid a high-risk emergency distal pancreatectomy.

3.
Ann R Coll Surg Engl ; 102(8): e187-e189, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32374219

ABSTRACT

We present a rare case of primary colorectal linitis plastica presenting as an acute admission to hospital with a wide range of systemic symptoms, sudden rapid deterioration and subsequent mortality. A postmortem examination revealed a primary linitis plastica of the colon and rectum with diffuse metastatic disease. To our knowledge, this is the first report of primary colorectal linitis plastica presenting as an acute deterioration as a result of extensive metastatic disease.


Subject(s)
Colitis, Ulcerative/complications , Colorectal Neoplasms , Linitis Plastica , Aged , Clinical Deterioration , Colon/pathology , Fatal Outcome , Humans , Male
4.
Ann R Coll Surg Engl ; 98(6): 409-12, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27055410

ABSTRACT

Introduction While surgery is the cornerstone of bowel cancer treatment, it comes with significant risks. Among patients aged over 80 years, 30-day mortality is 13%-15%, and additionally 12% will not return home and go on to live in supportive care. The question for patients and clinicians is whether operative surgery benefits elderly, frail patients. Methods Multidisciplinary team outcomes between October 2010 and April 2012 were searched to conduct a retrospective analysis of patients with known localised colorectal cancer who did not undergo surgery due to being deemed unfit. Results Twenty six patients survived for more than a few weeks following surgery, of whom 20% survived for at least 36 months. The average life expectancy following diagnosis was 1 year and 176 days, with a mean age at diagnosis of 87 years (range 77-93 years). One patient survived for 3 years and 240 days after diagnosis. Conclusions Although surgeons are naturally focused on surgical outcomes, non-operative outcomes are equally as important for patients. Elderly, frail patients benefit less from surgery for bowel cancer and have higher risks than younger cohorts, and this needs to be carefully discussed when jointly making the decision whether or not to operate.


Subject(s)
Colorectal Neoplasms/mortality , Conservative Treatment/mortality , Frail Elderly , Aged , Aged, 80 and over , Blood Transfusion/statistics & numerical data , Clinical Decision-Making , Colorectal Neoplasms/therapy , Humans , Life Expectancy , Retrospective Studies , Stents , United Kingdom/epidemiology
5.
Proc Natl Acad Sci U S A ; 104(37): 14741-6, 2007 Sep 11.
Article in English | MEDLINE | ID: mdl-17785412

ABSTRACT

In plants, silencing of mRNA can be transmitted from cell to cell and also over longer distances from roots to shoots. To investigate the long-distance mechanism, WT and mutant shoots were grafted onto roots silenced for an mRNA. We show that three genes involved in a chromatin silencing pathway, NRPD1a encoding RNA polymerase IVa, RNA-dependent RNA polymerase 2 (RDR2), and DICER-like 3 (DCL3), are required for reception of long-distance mRNA silencing in the shoot. A mutant representing a fourth gene in the pathway, argonaute4 (ago4), was also partially compromised in the reception of silencing. This pathway produces 24-nt siRNAs and resulted in decapped RNA, a known substrate for amplification of dsRNA by RDR6. Activation of silencing in grafted shoots depended on RDR6, but no 24-nt siRNAs were detected in mutant rdr6 shoots, indicating that RDR6 also plays a role in initial signal perception. After amplification of decapped transcripts, DCL4 and DCL2 act hierarchically as they do in antiviral resistance to produce 21- and 22-nt siRNAs, respectively, and these guide mRNA degradation. Several dcl genotypes were also tested for their capacity to transmit the mobile silencing signal from the rootstock. dcl1-8 and a dcl2 dcl3 dcl4 triple mutant are compromised in micro-RNA and siRNA biogenesis, respectively, but were unaffected in signal transmission.


Subject(s)
Arabidopsis/genetics , Cell Nucleus/genetics , Gene Silencing , RNA Interference , RNA, Messenger/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Argonaute Proteins , Cell Nucleus/metabolism , Epigenesis, Genetic , Models, Biological , Mutation , RNA, Messenger/metabolism , RNA, Small Interfering/metabolism , RNA-Dependent RNA Polymerase/genetics , RNA-Dependent RNA Polymerase/metabolism , Ribonuclease III/genetics , Ribonuclease III/metabolism
6.
Anaesthesia ; 60(4): 418-9; discussion 419, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15766357
7.
J Biol Chem ; 278(50): 50578-87, 2003 Dec 12.
Article in English | MEDLINE | ID: mdl-14514689

ABSTRACT

PRK1 is a serine/threonine kinase that belongs to the protein kinase C superfamily. It can be activated either by members of the Rho family of small G proteins, by proteolysis, or by interaction with lipids. Here we investigate the binding of PRK1 to RhoA and Rac1, two members of the Rho family. We demonstrate that PRK1 binds with a similar affinity to RhoA and Rac1. We present the solution structure of the second HR1 domain from the regulatory N-terminal region of PRK1, and we show that it forms an anti-parallel coiled-coil. In addition, we have used NMR to map the binding contacts of the HR1b domain with Rac1. These are compared with the contacts known to form between HR1a and RhoA. We have used mutagenesis to define the residues in Rac that are important for binding to HR1b. Surprisingly, as well as residues adjacent to Switch I, in Switch II, and in helix alpha5, it appears that the C-terminal stretch of basic amino acids in Rac is required for a high affinity interaction with HR1b.


Subject(s)
Protein Serine-Threonine Kinases/chemistry , rac1 GTP-Binding Protein/chemistry , rhoA GTP-Binding Protein/chemistry , Amino Acid Sequence , Amino Acids/chemistry , Animals , Binding Sites , Catalytic Domain , DNA Mutational Analysis , Guanosine Triphosphate/metabolism , Humans , Kinetics , Lipid Metabolism , Magnetic Resonance Spectroscopy , Models, Genetic , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , Mutation , Protein Binding , Protein Kinase C , Protein Serine-Threonine Kinases/metabolism , Protein Structure, Secondary , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Sequence Homology, Amino Acid , rac1 GTP-Binding Protein/metabolism , rhoA GTP-Binding Protein/metabolism
8.
J Immunol ; 167(6): 3454-62, 2001 Sep 15.
Article in English | MEDLINE | ID: mdl-11544338

ABSTRACT

Curcumin, in addition to its role as a spice, has been used for centuries to treat inflammatory disorders. Although the mechanism of action remains unclear, it has been shown to inhibit the activation of NF-kappaB and AP-1, transcription factors required for induction of many proinflammatory mediators. Due to its low toxicity it is currently under consideration as a broad anti-inflammatory, anti-tumor cell agent. In this study we investigated whether curcumin inhibited the response of gammadelta T cells to protease-resistant phosphorylated derivatives found in the cell wall of many pathogens. The results showed that curcumin levels > or =30 microM profoundly inhibited isopentenyl pyrophosphate-induced release of the chemokines macrophage inflammatory protein-1alpha and -1beta and RANTES. Curcumin also blocked isopentenyl pyrophosphate-induced activation of NF-kappaB and AP-1. Commencing around 16 h, treatment with curcumin lead to the induction of cell death that could not be reversed by APC, IL-15, or IL-2. This cytotoxicity was associated with increased annexin V reactivity, nuclear expression of active caspase-3, cleavage of poly(ADP-ribose) polymerase, translocation of apoptosis-inducing factor to the nucleus, and morphological evidence of nuclear disintegration. However, curcumin led to only large scale DNA chromatolysis, as determined by a combination of TUNEL staining and pulse-field and agarose gel electrophoresis, suggesting a predominantly apoptosis-inducing factor-mediated cell death process. We conclude that gammadelta T cells activated by these ubiquitous Ags are highly sensitive to curcumin, and that this effect may contribute to the anti-inflammatory properties of this compound.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antigens, Bacterial/immunology , Apoptosis/drug effects , Curcumin/pharmacology , DNA Fragmentation/drug effects , Hemiterpenes , Lymphocyte Activation/drug effects , Organophosphorus Compounds/immunology , Receptors, Antigen, T-Cell, gamma-delta/analysis , T-Lymphocyte Subsets/drug effects , Adult , Amino Acid Chloromethyl Ketones/pharmacology , Annexin A5/analysis , Antineoplastic Agents/pharmacology , Caspase 3 , Caspases/metabolism , Chemokine CCL4 , Chemokine CCL5/metabolism , Cycloheximide/pharmacology , Cysteine Proteinase Inhibitors/pharmacology , Electrophoresis, Agar Gel , Electrophoresis, Gel, Pulsed-Field , Enzyme Activation/drug effects , Flow Cytometry , Humans , In Situ Nick-End Labeling , Interleukin-15/pharmacology , Interleukin-2/pharmacology , Macrophage Inflammatory Proteins/metabolism , Molecular Weight , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Organophosphorus Compounds/antagonists & inhibitors , Organophosphorus Compounds/pharmacology , Phosphorylation , Protein Synthesis Inhibitors/pharmacology , T-Lymphocyte Subsets/immunology , Transcription Factor AP-1/antagonists & inhibitors , Transcription Factor AP-1/metabolism , Tumor Necrosis Factor-alpha/pharmacology
9.
J Pediatr Health Care ; 15(4): 187-93, 2001.
Article in English | MEDLINE | ID: mdl-11462126

ABSTRACT

The incidence of type 2 diabetes is increasing in the United States, and minority populations in particular seem to be affected. In the past, it was thought that type 2 diabetes occurred only in adults. However, an alarming epidemic has emerged, and children as young as 8 years of age are now being diagnosed with the disease. The purpose of this article is to present pediatric nurse practitioners with the most recent information about type 2 diabetes in children and adolescents, summarize current understanding about diagnosis, and outline treatment options.


Subject(s)
Diabetes Mellitus, Type 2 , Adolescent , Age of Onset , Child , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/nursing , Diabetes Mellitus, Type 2/therapy , Female , Humans , Male , Obesity/complications , Patient Education as Topic , Pediatric Nursing , Risk Factors , Self Care , United States/epidemiology
10.
Am J Pathol ; 158(6): 2057-66, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11395383

ABSTRACT

Nitric oxide generated by the inducible form of nitric oxide synthase (iNOS) may contribute to the pathogenesis of multiple sclerosis (MS). In this report, we studied postmortem tissues of MS patients for the expression of iNOS by in situ hybridization and immunocytochemistry. Immunocytochemistry for nitrotyrosine, a putative footprint for peroxynitrite formation was also performed. In acute MS lesions, intense reactivity for iNOS mRNA and protein was detected in reactive astrocytes throughout the lesion and in adjacent normal appearing white matter. Staining of macrophages, inflammatory cell infiltrates, and endothelial cells was variable from case to case, but generally detected only in acute lesions. In chronic MS lesions reactive astrocytes at the lesion edge were positive for iNOS whereas the lesion center was nonreactive. Normal appearing white matter demonstrated little reactivity, as did tissues from noninflamed control brains. Staining for nitrotyrosine was also detected in acute but not chronic MS lesions, and displayed a diffuse parenchymal, membranous, and perivascular pattern of immunoreactivity. These results support the conclusion that iNOS is induced in multiple cell types in MS lesions and that astrocyte-derived nitric oxide could be important in orchestrating inflammatory responses in MS, particularly at the blood-brain barrier.


Subject(s)
Multiple Sclerosis/metabolism , Nitric Oxide Synthase/biosynthesis , Tyrosine/analogs & derivatives , Tyrosine/biosynthesis , Adult , Aged , Female , Humans , Immunohistochemistry , In Situ Hybridization , Male , Middle Aged , Multiple Sclerosis/genetics , Multiple Sclerosis/pathology , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase/immunology , Nitric Oxide Synthase Type II , RNA, Messenger/biosynthesis , Transcription, Genetic , Tyrosine/genetics , Tyrosine/immunology
12.
J Neurosci ; 21(12): 4134-42, 2001 Jun 15.
Article in English | MEDLINE | ID: mdl-11404398

ABSTRACT

The cytokine interleukin-1beta (IL-1beta) is a potent activator of human astrocytes, inducing or modulating expression of multiple proinflammatory genes via activation of the transcription factors nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1). In this study, we examined whether IL-1beta signaling is regulated in these cells by extracellular nucleotides that are released at high concentrations under inflammatory conditions and act as ligands for members of the P2 receptor family. Using reporter constructs and electromobility shift assays, we found that cotreatment of astrocyte cultures with ATP (1-100 microm) significantly potentiated IL-1beta-mediated activation of NF-kappaB and AP-1 and that ATP alone activated AP-1. These effects were blocked by the P2 receptor antagonists XAMR 0721, periodate-oxidized ATP, and suramin. A role for ATP in modulating IL-1beta-mediated inflammatory gene expression was supported further by the observation that ATP potentiated the IL-1beta-induced expression of IL-8 mRNA and protein but strongly downregulated IP-10 expression. Reverse transcription-PCR and cloning demonstrated expression of the ATP-responsive P2 receptor subtypes P2Y(1), P2Y(2), and P2X(7), as well as the ATP-insensitive receptor P2Y(4). ADP, a selective agonist for P2Y(1), produced results similar to or greater than those obtained using ATP, whereas 2'-3'-O-(4-benzoyl-benzoyl)-ATP, a selective agonist for P2X(7), was less effective than ATP. In contrast, UTP, a selective agonist for P2Y(2) and P2Y(4), was ineffective. These studies indicate that different P2 receptor subtypes play distinct roles in the modulation of IL-1beta-mediated signal transduction in human astrocytes, and that signaling via P2 receptors may fine-tune the transcription of genes involved in inflammatory responses in the human CNS.


Subject(s)
Astrocytes/metabolism , Inflammation/metabolism , Interleukin-1/metabolism , Nucleotides/metabolism , Signal Transduction/immunology , Adenosine Triphosphate/analogs & derivatives , Adenosine Triphosphate/metabolism , Adenosine Triphosphate/pharmacology , Astrocytes/cytology , Astrocytes/drug effects , Cells, Cultured , Chemokine CXCL10 , Chemokines, CXC/genetics , Chemokines, CXC/metabolism , Drug Synergism , Extracellular Space/metabolism , Gene Expression Regulation/drug effects , Gene Expression Regulation/immunology , Genes, Reporter , Humans , Inflammation/immunology , Interleukin-1/pharmacology , Interleukin-8/biosynthesis , Interleukin-8/genetics , NF-kappa B/metabolism , Nucleotides/pharmacology , Purinergic P2 Receptor Agonists , Purinergic P2 Receptor Antagonists , RNA, Messenger/biosynthesis , Receptors, Purinergic P2/genetics , Receptors, Purinergic P2/metabolism , Signal Transduction/drug effects , Suramin/analogs & derivatives , Suramin/pharmacology , Transcription Factor AP-1/metabolism , Transcriptional Activation/drug effects
14.
Proc Natl Acad Sci U S A ; 98(11): 6295-300, 2001 May 22.
Article in English | MEDLINE | ID: mdl-11371643

ABSTRACT

Microglia arise from CD45(+) bone marrow precursors that colonize the fetal brain and play a key role in central nervous system inflammatory conditions. We report that parenchymal microglia are uncommitted myeloid progenitors of immature dendritic cells and macrophages by several criteria, including surface expression of "empty" class II MHC protein and their cysteine protease (cathepsin) profile. Microglia express receptors for stem cell factor and can be skewed toward more dendritic cell or macrophage-like profiles in response to the lineage growth factors granulocyte/macrophage colony-stimulating factor or macrophage colony-stimulating factor. Thus, in contrast to other organs, where terminally differentiated populations of resident dendritic cells and/or macrophages outnumber colonizing precursors, the majority of microglia within the brain remain in an undifferentiated state.


Subject(s)
Microglia/immunology , Neuronal Plasticity/immunology , Animals , Cathepsins/genetics , Cathepsins/immunology , Cell Differentiation , Cells, Cultured , Central Nervous System/cytology , Central Nervous System/immunology , Dendritic Cells/immunology , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/immunology , Histocompatibility Antigens Class II/immunology , Interferon-gamma/immunology , Interferon-gamma/pharmacology , Macrophages/immunology , Membrane Proteins/biosynthesis , Mice , Microglia/cytology , Microglia/drug effects , Stem Cell Factor/biosynthesis
15.
Public Health Nurs ; 18(1): 13-8, 2001.
Article in English | MEDLINE | ID: mdl-11251868

ABSTRACT

Public health nurses are increasingly called upon to justify the cost of care or to decide which of two alternative programs is more cost-effective. Cost studies can be complex and difficult to conduct, but an understanding of the basic techniques allows nurses to fully participate in planning, implementing, and evaluating programs that greatly impact the health of the community. This article defines some of the basic terms used in health economics, discusses standard methods of cost analysis, and provides an example of neonatal screening to illustrate methods of describing, measuring, and assigning a value to cost items.


Subject(s)
Cost-Benefit Analysis/methods , Health Care Costs/classification , Public Health Nursing/economics , Adrenal Hyperplasia, Congenital/diagnosis , Humans , Infant, Newborn , Neonatal Screening/economics , Quality-Adjusted Life Years , United States
16.
J Autoimmun ; 17(4): 261-71, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11771950

ABSTRACT

In this study, we assessed the expression of activation markers on gammadelta T cells in central nervous system (CNS) lesions of SJL mice adoptively sensitized to develop experimental autoimmune encephalomyelitis (EAE) using myelin basic protein-reactive T cells. Although disease expression is known to be dependent upon T cells that express the alphabeta T cell receptor (TCR), a role for gammadelta T cells has been implicated in some studies but not in others. Using three-color flow cytometric analysis of both total and gammadelta T cells in spleen and CNS, the data showed that expression of CD69 (early activation marker), CD62L (lymphocyte homing receptor), CD25 (IL-2Ralpha), CD122 (IL-2Rbeta) and CD95/CD95L (Fas/FasL), fluctuated on gammadelta T cells in EAE lesions in a disease-related fashion. Furthermore, the pattern of expression for these markers on gammadelta T cells was distinct from that found on the total lymphocyte population. Cytokine analysis of gammadelta T cells in the CNS demonstrated a bias towards a Th1-like cytokine profile. From these data, we conclude that gammadelta T cells in EAE lesions display an activated phenotype and form a dynamic component of the total lymphocyte population in the CNS, supporting a contributory role for these cells.


Subject(s)
Central Nervous System/immunology , Encephalomyelitis, Autoimmune, Experimental/immunology , Lymphocyte Activation/immunology , T-Lymphocyte Subsets/immunology , Animals , Antigens, CD/physiology , Antigens, Differentiation, T-Lymphocyte/physiology , Biomarkers , CD8 Antigens/physiology , Central Nervous System/pathology , Chronic Disease , Female , Immunophenotyping , L-Selectin/physiology , Lectins, C-Type , Mice , Receptors, Antigen, T-Cell, gamma-delta/immunology , Receptors, Interleukin-2/physiology , Recurrence , Spleen/physiology , fas Receptor/physiology
17.
J Neurosci ; 20(23): RC114, 2000 Dec 01.
Article in English | MEDLINE | ID: mdl-11090614

ABSTRACT

Vertebrate tissues use multiple junctional types to establish and maintain tissue architecture, including gap junctions for cytoplasmic connectivity and tight junctions (TJs) for paracellular and/or cell polarity barriers. The integral membrane proteins of gap junctions are connexins, whereas TJs are a complex between occludin and members of a recently characterized multigene family, the claudins. In normal brain, astrocytes are coupled by gap junctions composed primarily of connexin43 (Cx43), whereas TJs have not been detected in these cells. We now show that treatment of primary human astrocytes with the cytokine interleukin-1beta (IL-1beta) causes rapid induction of claudin-1, with an expression pattern reciprocal to loss of Cx43. Treatment also led to protracted downregulation of occludin but no change in expression of zonula occludens proteins ZO-1 and -2. Immunofluorescence staining localized claudin-1 to cell membranes in IL-1beta-treated astrocytes, whereas freeze-fracture replicas showed strand-like arrays of intramembranous particles in treated cells resembling rudimentary TJ assemblies. We conclude that in human astrocytes, IL-1beta regulates expression of the claudin multigene family and that gap and tight junction proteins are inversely regulated by this proinflammatory cytokine. We suggest that in pathological conditions of the human CNS, elevated IL-1beta expression fundamentally alters astrocyte-to-astrocyte connectivity.


Subject(s)
Astrocytes/metabolism , Connexin 43/metabolism , Connexins/metabolism , Interleukin-1/metabolism , Membrane Proteins/metabolism , Astrocytes/drug effects , Astrocytes/ultrastructure , Carrier Proteins/metabolism , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Cells, Cultured , Cerebral Cortex/cytology , Cerebral Cortex/drug effects , Cerebral Cortex/embryology , Cerebral Cortex/metabolism , Claudin-1 , Fluorescent Antibody Technique , Freeze Fracturing , Gene Expression Regulation/drug effects , Humans , Immunoblotting , Interleukin 1 Receptor Antagonist Protein , Interleukin-1/pharmacology , Membrane Proteins/genetics , Occludin , Phosphoproteins/metabolism , RNA, Messenger/biosynthesis , Receptors, Interleukin-1/metabolism , Sialoglycoproteins/metabolism , Sialoglycoproteins/pharmacology , Zonula Occludens Proteins , Zonula Occludens-1 Protein , Zonula Occludens-2 Protein
18.
J Neurosci ; 20(14): 5292-9, 2000 Jul 15.
Article in English | MEDLINE | ID: mdl-10884313

ABSTRACT

In human astrocytes, interleukin-1beta (IL-1beta) is a potent inducer of genes associated with inflammation. In this study, we tested the hypothesis that in primary cultures of human fetal astrocytes signaling by the P2 purinergic nucleotide receptor pathway contributes to, or modulates, cytokine-mediated signal transduction. Calcium imaging studies indicated that most cells in culture responded to ATP, whereas only a subpopulation responded to UTP. Pretreatment of astrocytes with P2 receptor antagonists, including suramin and periodate oxidized ATP (oATP), resulted in a significant downregulation of IL-1beta-stimulated expression of nitric oxide, tumor necrosis factor (TNFalpha), and IL-6 at both the protein and mRNA levels, without affecting cell viability. In cells transiently transfected with reporter constructs, IL-1beta demonstrated more potent activation of the transcription factors nuclear factor -kappaB (NF-kappaB) and activator protein-1 (AP-1) than TNFalpha. However, pretreatment with oATP downregulated activation of NF-kappaB and AP-1 by IL-1beta or TNFalpha. Electromobility shift assays using oligonucleotides containing specific NF-kappaB binding sequences confirmed that pretreatment with oATP or apyrase attenuated cytokine-mediated induction of this transcription factor. From these data, we conclude that P2 receptor-mediated signaling intersects with that of IL-1beta and TNFalpha to regulate responses to cytokines in the CNS. Because inflammation, trauma, and stress all lead to the release of high levels of extracellular nucleotides, such as ATP and UTP, signaling via P2 receptors may provide a mechanism whereby cells can sense and respond to events occurring in the extracellular environment and can fine tune the transcription of genes involved in the inflammatory response.


Subject(s)
Adenosine Triphosphate/analogs & derivatives , Astrocytes/metabolism , Interleukin-1/metabolism , Receptors, Purinergic P2/metabolism , Tumor Necrosis Factor-alpha/metabolism , Adenosine Triphosphate/pharmacology , Astrocytes/drug effects , Brain/embryology , Calcium/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Down-Regulation/drug effects , Gene Expression Regulation/drug effects , Genes, Reporter/drug effects , Humans , Interleukin-1/pharmacology , Interleukin-6/biosynthesis , Interleukin-6/genetics , NF-kappa B/metabolism , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type II , Nitrites/metabolism , Purinergic P2 Receptor Antagonists , RNA, Messenger/biosynthesis , Signal Transduction/drug effects , Transcription Factor AP-1/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/pharmacology , Uridine Triphosphate/pharmacology
19.
Glia ; 30(3): 279-89, 2000 May.
Article in English | MEDLINE | ID: mdl-10756077

ABSTRACT

In this study, the temporal and spatial expression of the chemotactic factor monocyte chemotactic protein-1 (MCP-1) was examined in the rabbit retina after challenge with the proinflammatory cytokine interleukin-1beta (IL-1). In these tissues, IL-1 induces an acute inflammatory response of the epiretinal vessels that peaks approximately 24 h postintraocular injection (pi) with the cytokine. At 2 h after challenge with IL-1, MCP-1 mRNA was expressed by perivascular microglial cells and astrocytes that form the glial limitans. Protein analysis at 3 h pi with IL-1 confirmed these sites of MCP-1 expression. The intensity of the mRNA and protein signals increased at 6 h and at 24 h. At these time points, MCP-1 message and protein also were detected in infiltrating macrophages and, at the latest time point, in endothelial cells as well. These data support the conclusion that IL-1 provides a strong stimulus for the rapid expression of MCP-1 mRNA and protein in retinal tissues, and they further support the role of endogenous glial cells as important sources of mediators involved in the regulation of inflammation occurring within the nervous system.


Subject(s)
Chemokine CCL2/metabolism , Interleukin-1/metabolism , Retina/metabolism , Animals , Chemokine CCL2/genetics , Female , Immunohistochemistry , In Situ Hybridization , RNA, Messenger/analysis , Rabbits , Time Factors
20.
J Immunol ; 164(4): 2120-30, 2000 Feb 15.
Article in English | MEDLINE | ID: mdl-10657666

ABSTRACT

Experimental autoimmune encephalomyelitis (EAE) is a demyelinating disease of the central nervous system (CNS) that is a model for multiple sclerosis. Previously, we showed that depletion of gamma delta T cells significantly reduced clinical and pathological signs of disease, which was associated with reduced expression of IL-1 beta, IL-6, TNF-alpha, and lymphotoxin at disease onset and a more persistent reduction in IFN-gamma. In this study, we analyzed the effect of gamma delta T cell depletion on chemokine and chemokine receptor expression. In the CNS of control EAE mice, mRNAs for RANTES, eotaxin, macrophage-inflammatory protein (MIP)-1 alpha, MIP-1 beta, MIP-2, inducible protein-10, and monocyte chemoattractant protein-1 were detected at disease onset, increased as disease progressed, and fell as clinical signs improved. In gamma delta T cell-depleted animals, all of the chemokine mRNAs were reduced at disease onset; but at the height of disease, expression was variable and showed no differences from control animals. mRNA levels then fell in parallel with control EAE mice. ELISA data confirmed reduced expression of MIP-1 alpha and monocyte chemoattractant protein-1 at disease onset in gamma delta T cell-depleted mice, and total T cell numbers were also reduced. In normal CNS mRNAs for CCR1, CCR3, and CCR5 were observed, and these were elevated in EAE animals. mRNAs for CCR2 were also detected in the CNS of affected mice. Depletion of gamma delta T cells reduced expression of CCR1 and CCR5 at disease onset only. We conclude that gamma delta T cells contribute to the development of EAE by promoting an inflammatory environment that serves to accelerate the inflammatory process in the CNS.


Subject(s)
Chemokines, CC/biosynthesis , Encephalomyelitis, Autoimmune, Experimental/immunology , Lymphocyte Depletion , Receptors, Antigen, T-Cell, gamma-delta/metabolism , Receptors, Chemokine/biosynthesis , Spinal Cord/immunology , Spinal Cord/metabolism , T-Lymphocyte Subsets/metabolism , Animals , Cell Movement/immunology , Chemokine CCL2/chemistry , Chemokine CCL2/immunology , Chemokine CCL4 , Chemokines, CC/genetics , Cricetinae , Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Gene Expression Regulation/immunology , Immunoglobulin G/administration & dosage , Immunohistochemistry , Injections, Intraperitoneal , Leukocyte Count , Macrophage Inflammatory Proteins/chemistry , Macrophage Inflammatory Proteins/immunology , Mice , Mice, Inbred Strains , Receptors, Chemokine/genetics , T-Lymphocyte Subsets/immunology
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